Commit Graph

1048 Commits

Author SHA1 Message Date
Linus Torvalds
7041503d3a netfslib, cachefiles and afs fixes
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCAAdFiEEqG5UsNXhtOCrfGQP+7dXa6fLC2sFAmFfE4oACgkQ+7dXa6fL
 C2txTBAAnWlEssljz7x09A/I9Js155U2hW9oDSoqkUxqZSe05oBbTPNycURvXAGZ
 wZhNZdD5Xc4ITjLmPQQclgkfWc+deq6UKzw8E58XmjiO1Uq6WcqUsC95M1USAmaM
 nRyhGrYRxJbv5eRDx3Ox3yoLntlSzvX1ZLhWr6DgAnb9uCdIWSGgy34XTd3aOSZa
 OEtPR/tvBZygxMV9wsflD2GNNLe7QDrOMUnvFSlmxBOUolclbHj9uhB/fQXN7frN
 Q/nf5QluBqZK13CIbiKSPy0wfl/hEdSFsOs5jAgMGm4IsZjSpsw2lvzxlfEaI7U/
 QzNHpqAc0ynPI9fbvs2LTkNFR1oe+njOIVvu0QMjOXEdnyOGEbFjX5eDNiKSAih4
 R3cNh2T16yUsx99lVbGkJAwbBQTmdp2yvfugQVX5qDNi+Ln8TFUKUHgruUv/FYJw
 hUjcOL6cjGdWORpWkxSoEariA6zDjKCWiyMu5w2yzSufI+DJ0AI6MQVOeqaX6dm6
 EldlxDO3w7uvXmwpH1RZsHXCqWfyiHn4P5LsSuVy/wM2O/VemaGQuHsxnLtMMJ+q
 HGniSziE6LAvF0RvBrngFGhAY6rqMIGzXK/+S1Z/YwM9+tYnoYhbANDhjmywrcI5
 GWaKePV5giTXlaI/XertjzEpQ2yo8r2HkYoVowV3NaRNrc3qgnQ=
 =X7mM
 -----END PGP SIGNATURE-----

Merge tag 'misc-fixes-20211007' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

Pull netfslib, cachefiles and afs fixes from David Howells:

 - Fix another couple of oopses in cachefiles tracing stemming from the
   possibility of passing in a NULL object pointer

 - Fix netfs_clear_unread() to set READ on the iov_iter so that source
   it is passed to doesn't do the wrong thing (some drivers look at the
   flag on iov_iter rather than other available information to determine
   the direction)

 - Fix afs_launder_page() to write back at the correct file position on
   the server so as not to corrupt data

* tag 'misc-fixes-20211007' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
  afs: Fix afs_launder_page() to set correct start file position
  netfs: Fix READ/WRITE confusion when calling iov_iter_xarray()
  cachefiles: Fix oops with cachefiles_cull() due to NULL object
2021-10-07 11:20:08 -07:00
David Howells
5c0522484e afs: Fix afs_launder_page() to set correct start file position
Fix afs_launder_page() to set the starting position of the StoreData RPC at
the offset into the page at which the modified data starts instead of at
the beginning of the page (the iov_iter is correctly offset).

The offset got lost during the conversion to passing an iov_iter into
afs_store_data().

Changes:
ver #2:
 - Use page_offset() rather than manually calculating it[1].

Fixes: bd80d8a80e ("afs: Use ITER_XARRAY for writing")
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeffrey Altman <jaltman@auristor.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
Link: https://lore.kernel.org/r/YST/0e92OdSH0zjg@casper.infradead.org/ [1]
Link: https://lore.kernel.org/r/162880783179.3421678.7795105718190440134.stgit@warthog.procyon.org.uk/ # v1
Link: https://lore.kernel.org/r/162937512409.1449272.18441473411207824084.stgit@warthog.procyon.org.uk/ # v1
Link: https://lore.kernel.org/r/162981148752.1901565.3663780601682206026.stgit@warthog.procyon.org.uk/ # v1
Link: https://lore.kernel.org/r/163005741670.2472992.2073548908229887941.stgit@warthog.procyon.org.uk/ # v2
Link: https://lore.kernel.org/r/163221839087.3143591.14278359695763025231.stgit@warthog.procyon.org.uk/ # v2
Link: https://lore.kernel.org/r/163292980654.4004896.7134735179887998551.stgit@warthog.procyon.org.uk/ # v2
2021-10-05 11:22:06 +01:00
David Howells
dcb442b133 afs: Fix kerneldoc warning shown up by W=1
Fix a kerneldoc warning in afs due to a partially documented internal
function by removing the kerneldoc marker.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
cc: linux-fsdevel@vger.kernel.org
cc: linux-doc@vger.kernel.org
Link: https://lore.kernel.org/r/163214005516.2945267.7000234432243167892.stgit@warthog.procyon.org.uk/ # rfc v1
Link: https://lore.kernel.org/r/163281899704.2790286.9177774252843775348.stgit@warthog.procyon.org.uk/ # rfc v2
2021-10-04 22:04:44 +01:00
Matthew Wilcox (Oracle)
490e016f22 mm/writeback: Add folio_wait_writeback()
wait_on_page_writeback_killable() only has one caller, so convert it to
call folio_wait_writeback_killable().  For the wait_on_page_writeback()
callers, add a compatibility wrapper around folio_wait_writeback().

Turning PageWriteback() into folio_test_writeback() eliminates a call
to compound_head() which saves 8 bytes and 15 bytes in the two
functions.  Unfortunately, that is more than offset by adding the
wait_on_page_writeback compatibility wrapper for a net increase in text
of 7 bytes.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Jeff Layton <jlayton@kernel.org>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: William Kucharski <william.kucharski@oracle.com>
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Reviewed-by: David Howells <dhowells@redhat.com>
2021-09-27 09:27:30 -04:00
David Howells
9d37e1cab2 afs: Fix updating of i_blocks on file/dir extension
When an afs file or directory is modified locally such that the total file
size is extended, i_blocks needs to be recalculated too.

Fix this by making afs_write_end() and afs_edit_dir_add() call
afs_set_i_size() rather than setting inode->i_size directly as that also
recalculates inode->i_blocks.

This can be tested by creating and writing into directories and files and
then examining them with du.  Without this change, directories show a 4
blocks (they start out at 2048 bytes) and files show 0 blocks; with this
change, they should show a number of blocks proportional to the file size
rounded up to 1024.

Fixes: 31143d5d51 ("AFS: implement basic file write support")
Fixes: 63a4681ff3 ("afs: Locally edit directory data for mkdir/create/unlink/...")
Reported-by: Markus Suvanto <markus.suvanto@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Marc Dionne <marc.dionne@auristor.com>
Tested-by: Markus Suvanto <markus.suvanto@gmail.com>
cc: linux-afs@lists.infradead.org
Link: https://lore.kernel.org/r/163113612442.352844.11162345591911691150.stgit@warthog.procyon.org.uk/
2021-09-13 09:14:21 +01:00
David Howells
b537a3c217 afs: Fix corruption in reads at fpos 2G-4G from an OpenAFS server
AFS-3 has two data fetch RPC variants, FS.FetchData and FS.FetchData64, and
Linux's afs client switches between them when talking to a non-YFS server
if the read size, the file position or the sum of the two have the upper 32
bits set of the 64-bit value.

This is a problem, however, since the file position and length fields of
FS.FetchData are *signed* 32-bit values.

Fix this by capturing the capability bits obtained from the fileserver when
it's sent an FS.GetCapabilities RPC, rather than just discarding them, and
then picking out the VICED_CAPABILITY_64BITFILES flag.  This can then be
used to decide whether to use FS.FetchData or FS.FetchData64 - and also
FS.StoreData or FS.StoreData64 - rather than using upper_32_bits() to
switch on the parameter values.

This capabilities flag could also be used to limit the maximum size of the
file, but all servers must be checked for that.

Note that the issue does not exist with FS.StoreData - that uses *unsigned*
32-bit values.  It's also not a problem with Auristor servers as its
YFS.FetchData64 op uses unsigned 64-bit values.

This can be tested by cloning a git repo through an OpenAFS client to an
OpenAFS server and then doing "git status" on it from a Linux afs
client[1].  Provided the clone has a pack file that's in the 2G-4G range,
the git status will show errors like:

	error: packfile .git/objects/pack/pack-5e813c51d12b6847bbc0fcd97c2bca66da50079c.pack does not match index
	error: packfile .git/objects/pack/pack-5e813c51d12b6847bbc0fcd97c2bca66da50079c.pack does not match index

This can be observed in the server's FileLog with something like the
following appearing:

Sun Aug 29 19:31:39 2021 SRXAFS_FetchData, Fid = 2303380852.491776.3263114, Host 192.168.11.201:7001, Id 1001
Sun Aug 29 19:31:39 2021 CheckRights: len=0, for host=192.168.11.201:7001
Sun Aug 29 19:31:39 2021 FetchData_RXStyle: Pos 18446744071815340032, Len 3154
Sun Aug 29 19:31:39 2021 FetchData_RXStyle: file size 2400758866
...
Sun Aug 29 19:31:40 2021 SRXAFS_FetchData returns 5

Note the file position of 18446744071815340032.  This is the requested file
position sign-extended.

Fixes: b9b1f8d593 ("AFS: write support fixes")
Reported-by: Markus Suvanto <markus.suvanto@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Marc Dionne <marc.dionne@auristor.com>
Tested-by: Markus Suvanto <markus.suvanto@gmail.com>
cc: linux-afs@lists.infradead.org
cc: openafs-devel@openafs.org
Link: https://bugzilla.kernel.org/show_bug.cgi?id=214217#c9 [1]
Link: https://lore.kernel.org/r/951332.1631308745@warthog.procyon.org.uk/
2021-09-13 09:14:21 +01:00
David Howells
4fe6a94682 afs: Try to avoid taking RCU read lock when checking vnode validity
Try to avoid taking the RCU read lock when checking the validity of a
vnode's callback state.  The only thing it's needed for is to pin the
parent volume's server list whilst we search it to find the record of the
server we're currently using to see if it has been reinitialised (ie. it
sent us a CB.InitCallBackState* RPC).

Do this by the following means:

 (1) Keep an additional per-cell counter (fs_s_break) that's incremented
     each time any of the fileservers in the cell reinitialises.

     Since the new counter can be accessed without RCU from the vnode, we
     can check that first - and only if it differs, get the RCU read lock
     and check the volume's server list.

 (2) Replace afs_get_s_break_rcu() with afs_check_server_good() which now
     indicates whether the callback promise is still expected to be present
     on the server.  This does the checks as described in (1).

 (3) Restructure afs_check_validity() to take account of the change in (2).

     We can also get rid of the valid variable and just use the need_clear
     variable with the addition of the afs_cb_break_no_promise reason.

 (4) afs_check_validity() probably shouldn't be altering vnode->cb_v_break
     and vnode->cb_s_break when it doesn't have cb_lock exclusively locked.

     Move the change to vnode->cb_v_break to __afs_break_callback().

     Delegate the change to vnode->cb_s_break to afs_select_fileserver()
     and set vnode->cb_fs_s_break there also.

 (5) afs_validate() no longer needs to get the RCU read lock around its
     call to afs_check_validity() - and can skip the call entirely if we
     don't have a promise.

Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Markus Suvanto <markus.suvanto@gmail.com>
cc: linux-afs@lists.infradead.org
Link: https://lore.kernel.org/r/163111669583.283156.1397603105683094563.stgit@warthog.procyon.org.uk/
2021-09-13 09:10:39 +01:00
David Howells
6e0e99d58a afs: Fix mmap coherency vs 3rd-party changes
Fix the coherency management of mmap'd data such that 3rd-party changes
become visible as soon as possible after the callback notification is
delivered by the fileserver.  This is done by the following means:

 (1) When we break a callback on a vnode specified by the CB.CallBack call
     from the server, we queue a work item (vnode->cb_work) to go and
     clobber all the PTEs mapping to that inode.

     This causes the CPU to trip through the ->map_pages() and
     ->page_mkwrite() handlers if userspace attempts to access the page(s)
     again.

     (Ideally, this would be done in the service handler for CB.CallBack,
     but the server is waiting for our reply before considering, and we
     have a list of vnodes, all of which need breaking - and the process of
     getting the mmap_lock and stripping the PTEs on all CPUs could be
     quite slow.)

 (2) Call afs_validate() from the ->map_pages() handler to check to see if
     the file has changed and to get a new callback promise from the
     server.

Also handle the fileserver telling us that it's dropping all callbacks,
possibly after it's been restarted by sending us a CB.InitCallBackState*
call by the following means:

 (3) Maintain a per-cell list of afs files that are currently mmap'd
     (cell->fs_open_mmaps).

 (4) Add a work item to each server that is invoked if there are any open
     mmaps when CB.InitCallBackState happens.  This work item goes through
     the aforementioned list and invokes the vnode->cb_work work item for
     each one that is currently using this server.

     This causes the PTEs to be cleared, causing ->map_pages() or
     ->page_mkwrite() to be called again, thereby calling afs_validate()
     again.

I've chosen to simply strip the PTEs at the point of notification reception
rather than invalidate all the pages as well because (a) it's faster, (b)
we may get a notification for other reasons than the data being altered (in
which case we don't want to clobber the pagecache) and (c) we need to ask
the server to find out - and I don't want to wait for the reply before
holding up userspace.

This was tested using the attached test program:

	#include <stdbool.h>
	#include <stdio.h>
	#include <stdlib.h>
	#include <unistd.h>
	#include <fcntl.h>
	#include <sys/mman.h>
	int main(int argc, char *argv[])
	{
		size_t size = getpagesize();
		unsigned char *p;
		bool mod = (argc == 3);
		int fd;
		if (argc != 2 && argc != 3) {
			fprintf(stderr, "Format: %s <file> [mod]\n", argv[0]);
			exit(2);
		}
		fd = open(argv[1], mod ? O_RDWR : O_RDONLY);
		if (fd < 0) {
			perror(argv[1]);
			exit(1);
		}

		p = mmap(NULL, size, mod ? PROT_READ|PROT_WRITE : PROT_READ,
			 MAP_SHARED, fd, 0);
		if (p == MAP_FAILED) {
			perror("mmap");
			exit(1);
		}
		for (;;) {
			if (mod) {
				p[0]++;
				msync(p, size, MS_ASYNC);
				fsync(fd);
			}
			printf("%02x", p[0]);
			fflush(stdout);
			sleep(1);
		}
	}

It runs in two modes: in one mode, it mmaps a file, then sits in a loop
reading the first byte, printing it and sleeping for a second; in the
second mode it mmaps a file, then sits in a loop incrementing the first
byte and flushing, then printing and sleeping.

Two instances of this program can be run on different machines, one doing
the reading and one doing the writing.  The reader should see the changes
made by the writer, but without this patch, they aren't because validity
checking is being done lazily - only on entry to the filesystem.

Testing the InitCallBackState change is more complicated.  The server has
to be taken offline, the saved callback state file removed and then the
server restarted whilst the reading-mode program continues to run.  The
client machine then has to poke the server to trigger the InitCallBackState
call.

Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Markus Suvanto <markus.suvanto@gmail.com>
cc: linux-afs@lists.infradead.org
Link: https://lore.kernel.org/r/163111668833.283156.382633263709075739.stgit@warthog.procyon.org.uk/
2021-09-13 09:10:39 +01:00
David Howells
63d49d843e afs: Fix incorrect triggering of sillyrename on 3rd-party invalidation
The AFS filesystem is currently triggering the silly-rename cleanup from
afs_d_revalidate() when it sees that a dentry has been changed by a third
party[1].  It should not be doing this as the cleanup includes deleting the
silly-rename target file on iput.

Fix this by removing the places in the d_revalidate handling that validate
anything other than the directory and the dirent.  It probably should not
be looking to validate the target inode of the dentry also.

This includes removing the point in afs_d_revalidate() where the inode that
a dentry used to point to was marked as being deleted (AFS_VNODE_DELETED).
We don't know it got deleted.  It could have been renamed or it could have
hard links remaining.

This was reproduced by cloning a git repo onto an afs volume on one
machine, switching to another machine and doing "git status", then
switching back to the first and doing "git status".  The second status
would show weird output due to ".git/index" getting deleted by the above
mentioned mechanism.

A simpler way to do it is to do:

	machine 1: touch a
	machine 2: touch b; mv -f b a
	machine 1: stat a

on an afs volume.  The bug shows up as the stat failing with ENOENT and the
file server log showing that machine 1 deleted "a".

Fixes: 79ddbfa500 ("afs: Implement sillyrename for unlink and rename")
Reported-by: Markus Suvanto <markus.suvanto@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Markus Suvanto <markus.suvanto@gmail.com>
cc: linux-afs@lists.infradead.org
Link: https://bugzilla.kernel.org/show_bug.cgi?id=214217#c4 [1]
Link: https://lore.kernel.org/r/163111668100.283156.3851669884664475428.stgit@warthog.procyon.org.uk/
2021-09-13 09:10:39 +01:00
David Howells
3978d81652 afs: Add missing vnode validation checks
afs_d_revalidate() should only be validating the directory entry it is
given and the directory to which that belongs; it shouldn't be validating
the inode/vnode to which that dentry points.  Besides, validation need to
be done even if we don't call afs_d_revalidate() - which might be the case
if we're starting from a file descriptor.

In order for afs_d_revalidate() to be fixed, validation points must be
added in some other places.  Certain directory operations, such as
afs_unlink(), already check this, but not all and not all file operations
either.

Note that the validation of a vnode not only checks to see if the
attributes we have are correct, but also gets a promise from the server to
notify us if that file gets changed by a third party.

Add the following checks:

 - Check the vnode we're going to make a hard link to.
 - Check the vnode we're going to move/rename.
 - Check the vnode we're going to read from.
 - Check the vnode we're going to write to.
 - Check the vnode we're going to sync.
 - Check the vnode we're going to make a mapped page writable for.

Some of these aren't strictly necessary as we're going to perform a server
operation that might get the attributes anyway from which we can determine
if something changed - though it might not get us a callback promise.

Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Markus Suvanto <markus.suvanto@gmail.com>
cc: linux-afs@lists.infradead.org
Link: https://lore.kernel.org/r/163111667354.283156.12720698333342917516.stgit@warthog.procyon.org.uk/
2021-09-13 09:10:39 +01:00
David Howells
581b2027af afs: Fix page leak
There's a loop in afs_extend_writeback() that adds extra pages to a write
we want to make to improve the efficiency of the writeback by making it
larger.  This loop stops, however, if we hit a page we can't write back
from immediately, but it doesn't get rid of the page ref we speculatively
acquired.

This was caused by the removal of the cleanup loop when the code switched
from using find_get_pages_contig() to xarray scanning as the latter only
gets a single page at a time, not a batch.

Fix this by putting the page on a ref on an early break from the loop.
Unfortunately, we can't just add that page to the pagevec we're employing
as we'll go through that and add those pages to the RPC call.

This was found by the generic/074 test.  It leaks ~4GiB of RAM each time it
is run - which can be observed with "top".

Fixes: e87b03f583 ("afs: Prepare for use of THPs")
Reported-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-and-tested-by: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
Link: https://lore.kernel.org/r/163111666635.283156.177701903478910460.stgit@warthog.procyon.org.uk/
2021-09-10 22:14:51 +01:00
David Howells
345e1ae0c6 afs: Fix missing put on afs_read objects and missing get on the key therein
The afs_read objects created by afs_req_issue_op() get leaked because
afs_alloc_read() returns a ref and then afs_fetch_data() gets its own ref
which is released when the operation completes, but the initial ref is
never released.

Fix this by discarding the initial ref at the end of afs_req_issue_op().

This leak also covered another bug whereby a ref isn't got on the key
attached to the read record by afs_req_issue_op().  This isn't a problem as
long as the afs_read req never goes away...

Fix this by calling key_get() in afs_req_issue_op().

This was found by the generic/074 test.  It leaks a bunch of kmalloc-192
objects each time it is run, which can be observed by watching
/proc/slabinfo.

Fixes: f7605fa869cf ("afs: Fix leak of afs_read objects")
Reported-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-and-tested-by: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
Link: https://lore.kernel.org/r/163010394740.3035676.8516846193899793357.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163111665914.283156.3038561975681836591.stgit@warthog.procyon.org.uk/
2021-09-10 22:14:51 +01:00
Jeff Layton
f7e33bdbd6 fs: remove mandatory file locking support
We added CONFIG_MANDATORY_FILE_LOCKING in 2015, and soon after turned it
off in Fedora and RHEL8. Several other distros have followed suit.

I've heard of one problem in all that time: Someone migrated from an
older distro that supported "-o mand" to one that didn't, and the host
had a fstab entry with "mand" in it which broke on reboot. They didn't
actually _use_ mandatory locking so they just removed the mount option
and moved on.

This patch rips out mandatory locking support wholesale from the kernel,
along with the Kconfig option and the Documentation file. It also
changes the mount code to ignore the "mand" mount option instead of
erroring out, and to throw a big, ugly warning.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
2021-08-23 06:15:36 -04:00
Jiapeng Chong
b428081282 afs: Remove redundant assignment to ret
Variable ret is set to -ENOENT and -ENOMEM but this value is never
read as it is overwritten or not used later on, hence it is a
redundant assignment and can be removed.

Cleans up the following clang-analyzer warning:

fs/afs/dir.c:2014:4: warning: Value stored to 'ret' is never read
[clang-analyzer-deadcode.DeadStores].

fs/afs/dir.c:659:2: warning: Value stored to 'ret' is never read
[clang-analyzer-deadcode.DeadStores].

[DH made the following modifications:

 - In afs_rename(), -ENOMEM should be placed in op->error instead of ret,
   rather than the assignment being removed entirely.  afs_put_operation()
   will pick it up from there and return it.

 - If afs_sillyrename() fails, its error code should be placed in op->error
   rather than in ret also.
]

Fixes: e49c7b2f6d ("afs: Build an abstraction around an "operation" concept")
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
Link: https://lore.kernel.org/r/1619691492-83866-1-git-send-email-jiapeng.chong@linux.alibaba.com
Link: https://lore.kernel.org/r/162609465444.3133237.7562832521724298900.stgit@warthog.procyon.org.uk/ # v1
Link: https://lore.kernel.org/r/162610729052.3408253.17364333638838151299.stgit@warthog.procyon.org.uk/ # v2
2021-07-21 15:11:22 +01:00
David Howells
5a972474cf afs: Fix setting of writeback_index
Fix afs_writepages() to always set mapping->writeback_index to a page index
and not a byte position[1].

Fixes: 31143d5d51 ("AFS: implement basic file write support")
Reported-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
Link: https://lore.kernel.org/r/CAB9dFdvHsLsw7CMnB+4cgciWDSqVjuij4mH3TaXnHQB8sz5rHw@mail.gmail.com/ [1]
Link: https://lore.kernel.org/r/162610728339.3408253.4604750166391496546.stgit@warthog.procyon.org.uk/ # v2 (no v1)
2021-07-21 15:10:23 +01:00
Tom Rix
afe6949862 afs: check function return
Static analysis reports this problem

write.c:773:29: warning: Assigned value is garbage or undefined
  mapping->writeback_index = next;
                           ^ ~~~~
The call to afs_writepages_region() can return without setting
next.  So check the function return before using next.

Changes:
 ver #2:
   - Need to fix the range_cyclic case also[1].

Fixes: e87b03f583 ("afs: Prepare for use of THPs")
Signed-off-by: Tom Rix <trix@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
Link: https://lore.kernel.org/r/20210430155031.3287870-1-trix@redhat.com
Link: https://lore.kernel.org/r/CAB9dFdvHsLsw7CMnB+4cgciWDSqVjuij4mH3TaXnHQB8sz5rHw@mail.gmail.com/ [1]
Link: https://lore.kernel.org/r/162609464716.3133237.10354897554363093252.stgit@warthog.procyon.org.uk/ # v1
Link: https://lore.kernel.org/r/162610727640.3408253.8687445613469681311.stgit@warthog.procyon.org.uk/ # v2
2021-07-21 15:10:23 +01:00
David Howells
6c881ca0b3 afs: Fix tracepoint string placement with built-in AFS
To quote Alexey[1]:

    I was adding custom tracepoint to the kernel, grabbed full F34 kernel
    .config, disabled modules and booted whole shebang as VM kernel.

    Then did

	perf record -a -e ...

    It crashed:

	general protection fault, probably for non-canonical address 0x435f5346592e4243: 0000 [#1] SMP PTI
	CPU: 1 PID: 842 Comm: cat Not tainted 5.12.6+ #26
	Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-1.fc33 04/01/2014
	RIP: 0010:t_show+0x22/0xd0

    Then reproducer was narrowed to

	# cat /sys/kernel/tracing/printk_formats

    Original F34 kernel with modules didn't crash.

    So I started to disable options and after disabling AFS everything
    started working again.

    The root cause is that AFS was placing char arrays content into a
    section full of _pointers_ to strings with predictable consequences.

    Non canonical address 435f5346592e4243 is "CB.YFS_" which came from
    CM_NAME macro.

    Steps to reproduce:

	CONFIG_AFS=y
	CONFIG_TRACING=y

	# cat /sys/kernel/tracing/printk_formats

Fix this by the following means:

 (1) Add enum->string translation tables in the event header with the AFS
     and YFS cache/callback manager operations listed by RPC operation ID.

 (2) Modify the afs_cb_call tracepoint to print the string from the
     translation table rather than using the string at the afs_call name
     pointer.

 (3) Switch translation table depending on the service we're being accessed
     as (AFS or YFS) in the tracepoint print clause.  Will this cause
     problems to userspace utilities?

     Note that the symbolic representation of the YFS service ID isn't
     available to this header, so I've put it in as a number.  I'm not sure
     if this is the best way to do this.

 (4) Remove the name wrangling (CM_NAME) macro and put the names directly
     into the afs_call_type structs in cmservice.c.

Fixes: 8e8d7f13b6 ("afs: Add some tracepoints")
Reported-by: Alexey Dobriyan (SK hynix) <adobriyan@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Reviewed-by: Marc Dionne <marc.dionne@auristor.com>
cc: Andrew Morton <akpm@linux-foundation.org>
cc: linux-afs@lists.infradead.org
Link: https://lore.kernel.org/r/YLAXfvZ+rObEOdc%2F@localhost.localdomain/ [1]
Link: https://lore.kernel.org/r/643721.1623754699@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/162430903582.2896199.6098150063997983353.stgit@warthog.procyon.org.uk/ # v1
Link: https://lore.kernel.org/r/162609463957.3133237.15916579353149746363.stgit@warthog.procyon.org.uk/ # v1 (repost)
Link: https://lore.kernel.org/r/162610726860.3408253.445207609466288531.stgit@warthog.procyon.org.uk/ # v2
2021-07-21 15:08:35 +01:00
Linus Torvalds
9e736cf7d6 netfslib fixes
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCAAdFiEEqG5UsNXhtOCrfGQP+7dXa6fLC2sFAmDQ9Z4ACgkQ+7dXa6fL
 C2sVfg/9H3OlL4Vwv5CERgb5kbDoALAh5epYMFyvNVy9l5iTvYekxG3qna6ee0+G
 pTRHSU5tZUCUslpafv8LUz1RE/iM127y+BP+qq2joG9jkT4q3QfeV4oDr+dgZWCL
 obp+rjQSTKkaGh3eqjDx7gCSp5mqQI/M8MXe1VOXxUzAnsf2nH4iJLv/A9NN17xW
 l7sQfZJGHD1BPqsxxFiSr+UCkCLuLDybUDYL6+PZcFu0jSON0h4yEtIwsAA7a1Zw
 TvgUpequrbyTORI3sHJ8eIixWosh4yLTJ4pDqs8qDqq3Wm5eTZjss0wxEaVfpaTu
 cg/CcNUBiHJ/6Q8r+JiuPbEnfnQ9woL8951/CNi+cOGhTy9LNoG70orSZKKynmW5
 QmpYBK5BkM57EPj7DYZJRI1Bwy41pJapFj8tXbMjObU+ZyaXMysmBDanIRK/cLoy
 fr4Sz+1D8yJPQ0GDgC4051CxrhynOEnRo8JbESg8CD4PnqFeM7EoCh48H2oVvR4N
 9v2xuaRyBvi2KTmKSktRe+s1DS80acVMUYP33nT2zAthvL91VVgMY3Hz2/QrlAp8
 h1hREME8aRcN4LrBIgp/ET150hUh44U2A07PqnYYe0653MH7aHHFfk134ZuTmbub
 Pfc1MHtWgPAWN4c140ILBRTidJeShszoJGgpD6tflkj10VI2s34=
 =2c6l
 -----END PGP SIGNATURE-----

Merge tag 'netfs-fixes-20210621' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

Pull netfs fixes from David Howells:
 "This contains patches to fix netfs_write_begin() and afs_write_end()
  in the following ways:

  (1) In netfs_write_begin(), extract the decision about whether to skip
      a page out to its own helper and have that clear around the region
      to be written, but not clear that region. This requires the
      filesystem to patch it up afterwards if the hole doesn't get
      completely filled.

  (2) Use offset_in_thp() in (1) rather than manually calculating the
      offset into the page.

  (3) Due to (1), afs_write_end() now needs to handle short data write
      into the page by generic_perform_write(). I've adopted an
      analogous approach to ceph of just returning 0 in this case and
      letting the caller go round again.

  It also adds a note that (in the future) the len parameter may extend
  beyond the page allocated. This is because the page allocation is
  deferred to write_begin() and that gets to decide what size of THP to
  allocate."

Jeff Layton points out:
 "The netfs fix in particular fixes a data corruption bug in cephfs"

* tag 'netfs-fixes-20210621' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
  netfs: fix test for whether we can skip read when writing beyond EOF
  afs: Fix afs_write_end() to handle short writes
2021-06-25 09:41:29 -07:00
David Howells
66e9c6a86b afs: Fix afs_write_end() to handle short writes
Fix afs_write_end() to correctly handle a short copy into the intended
write region of the page.  Two things are necessary:

 (1) If the page is not up to date, then we should just return 0
     (ie. indicating a zero-length copy).  The loop in
     generic_perform_write() will go around again, possibly breaking up the
     iterator into discrete chunks[1].

     This is analogous to commit b9de313cf0
     for ceph.

 (2) The page should not have been set uptodate if it wasn't completely set
     up by netfs_write_begin() (this will be fixed in the next patch), so
     we need to set uptodate here in such a case.

Also remove the assertion that was checking that the page was set uptodate
since it's now set uptodate if it wasn't already a few lines above.  The
assertion was from when uptodate was set elsewhere.

Changes:
v3: Remove the handling of len exceeding the end of the page.

Fixes: 3003bbd069 ("afs: Use the netfs_write_begin() helper")
Reported-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
cc: Al Viro <viro@zeniv.linux.org.uk>
cc: linux-afs@lists.infradead.org
Link: https://lore.kernel.org/r/YMwVp268KTzTf8cN@zeniv-ca.linux.org.uk/ [1]
Link: https://lore.kernel.org/r/162367682522.460125.5652091227576721609.stgit@warthog.procyon.org.uk/ # v1
Link: https://lore.kernel.org/r/162391825688.1173366.3437507255136307904.stgit@warthog.procyon.org.uk/ # v2
2021-06-21 21:23:36 +01:00
Matthew Wilcox (Oracle)
9620ad86d0 afs: Re-enable freezing once a page fault is interrupted
If a task is killed during a page fault, it does not currently call
sb_end_pagefault(), which means that the filesystem cannot be frozen
at any time thereafter.  This may be reported by lockdep like this:

====================================
WARNING: fsstress/10757 still has locks held!
5.13.0-rc4-build4+ #91 Not tainted
------------------------------------
1 lock held by fsstress/10757:
 #0: ffff888104eac530
 (
sb_pagefaults

as filesystem freezing is modelled as a lock.

Fix this by removing all the direct returns from within the function,
and using 'ret' to indicate whether we were interrupted or successful.

Fixes: 1cf7a1518a ("afs: Implement shared-writeable mmap")
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: David Howells <dhowells@redhat.com>
cc: linux-afs@lists.infradead.org
Link: https://lore.kernel.org/r/20210616154900.1958373-1-willy@infradead.org/
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-06-18 13:49:07 -07:00
Dan Carpenter
a33d62662d afs: Fix an IS_ERR() vs NULL check
The proc_symlink() function returns NULL on error, it doesn't return
error pointers.

Fixes: 5b86d4ff5d ("afs: Implement network namespacing")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David Howells <dhowells@redhat.com>
cc: linux-afs@lists.infradead.org
Link: https://lore.kernel.org/r/YLjMRKX40pTrJvgf@mwanda/
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-06-15 07:42:26 -07:00
Marc Dionne
dc2557308e afs: Fix partial writeback of large files on fsync and close
In commit e87b03f583 ("afs: Prepare for use of THPs"), the return
value for afs_write_back_from_locked_page was changed from a number
of pages to a length in bytes.  The loop in afs_writepages_region uses
the return value to compute the index that will be used to find dirty
pages in the next iteration, but treats it as a number of pages and
wrongly multiplies it by PAGE_SIZE.  This gives a very large index value,
potentially skipping any dirty data that was not covered in the first
pass, which is limited to 256M.

This causes fsync(), and indirectly close(), to only do a partial
writeback of a large file's dirty data.  The rest is eventually written
back by background threads after dirty_expire_centisecs.

Fixes: e87b03f583 ("afs: Prepare for use of THPs")
Signed-off-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeffrey Altman <jaltman@auristor.com>
cc: linux-afs@lists.infradead.org
Link: https://lore.kernel.org/r/20210604175504.4055-1-marc.c.dionne@gmail.com/
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-06-07 12:56:05 -07:00
David Howells
f610a5a29c afs: Fix the nlink handling of dir-over-dir rename
Fix rename of one directory over another such that the nlink on the deleted
directory is cleared to 0 rather than being decremented to 1.

This was causing the generic/035 xfstest to fail.

Fixes: e49c7b2f6d ("afs: Build an abstraction around an "operation" concept")
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
Link: https://lore.kernel.org/r/162194384460.3999479.7605572278074191079.stgit@warthog.procyon.org.uk/ # v1
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-27 06:23:58 -10:00
Gustavo A. R. Silva
b2db6c35ba afs: Fix fall-through warnings for Clang
In preparation to enable -Wimplicit-fallthrough for Clang, fix multiple
warnings by explicitly adding multiple fallthrough pseudo-keywords in
places where the code is intended to fall through to the next case.

Link: https://github.com/KSPP/linux/issues/115
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeffrey Altman <jaltman@auristor.com>
cc: linux-afs@lists.infradead.org
cc: linux-hardening@vger.kernel.org
Link: https://lore.kernel.org/r/51150b54e0b0431a2c401cd54f2c4e7f50e94601.1605896059.git.gustavoars@kernel.org/ # v1
Link: https://lore.kernel.org/r/20210420211615.GA51432@embeddedor/ # v2
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-25 07:30:34 -10:00
David Howells
22650f1481 afs: Fix speculative status fetches
The generic/464 xfstest causes kAFS to emit occasional warnings of the
form:

        kAFS: vnode modified {100055:8a} 30->31 YFS.StoreData64 (c=6015)

This indicates that the data version received back from the server did not
match the expected value (the DV should be incremented monotonically for
each individual modification op committed to a vnode).

What is happening is that a lookup call is doing a bulk status fetch
speculatively on a bunch of vnodes in a directory besides getting the
status of the vnode it's actually interested in.  This is racing with a
StoreData operation (though it could also occur with, say, a MakeDir op).

On the client, a modification operation locks the vnode, but the bulk
status fetch only locks the parent directory, so no ordering is imposed
there (thereby avoiding an avenue to deadlock).

On the server, the StoreData op handler doesn't lock the vnode until it's
received all the request data, and downgrades the lock after committing the
data until it has finished sending change notifications to other clients -
which allows the status fetch to occur before it has finished.

This means that:

 - a status fetch can access the target vnode either side of the exclusive
   section of the modification

 - the status fetch could start before the modification, yet finish after,
   and vice-versa.

 - the status fetch and the modification RPCs can complete in either order.

 - the status fetch can return either the before or the after DV from the
   modification.

 - the status fetch might regress the locally cached DV.

Some of these are handled by the previous fix[1], but that's not sufficient
because it checks the DV it received against the DV it cached at the start
of the op, but the DV might've been updated in the meantime by a locally
generated modification op.

Fix this by the following means:

 (1) Keep track of when we're performing a modification operation on a
     vnode.  This is done by marking vnode parameters with a 'modification'
     note that causes the AFS_VNODE_MODIFYING flag to be set on the vnode
     for the duration.

 (2) Alter the speculation race detection to ignore speculative status
     fetches if either the vnode is marked as being modified or the data
     version number is not what we expected.

Note that whilst the "vnode modified" warning does get recovered from as it
causes the client to refetch the status at the next opportunity, it will
also invalidate the pagecache, so changes might get lost.

Fixes: a9e5c87ca7 ("afs: Fix speculative status fetch going out of order wrt to modifications")
Reported-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-and-reviewed-by: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
Link: https://lore.kernel.org/r/160605082531.252452.14708077925602709042.stgit@warthog.procyon.org.uk/ [1]
Link: https://lore.kernel.org/linux-fsdevel/161961335926.39335.2552653972195467566.stgit@warthog.procyon.org.uk/ # v1
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-01 11:55:36 -07:00
Linus Torvalds
fafe1e39ed AFS: Use the new netfs lib
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCAAdFiEEqG5UsNXhtOCrfGQP+7dXa6fLC2sFAmCHJJAACgkQ+7dXa6fL
 C2uv0A//S/sJyToPtj3xbzmRVmSGGWFYNRMaxBD2gYAq7swbDNiX4ZbBCe8A4FBY
 zedeMfoNztHIRB2M9vvnhG4HJWXPKq2BaT0xzeteCcmZ65b5zBOrAXue0PQPqE20
 xmK1RDls/y5Y2FaF92Ay0VZzXW7+y/M+RRSo+FCFzrIgpJrPprTnlZigrECYauGJ
 Qdsv26rQ0flK6tyi6GVuWZIMvpINCt3WwpwQTkAUewz2VewA1tZ1xFe70sP0vF7R
 MJNaS6A4uJmvoJJzb8rqdnBGiu76+TxmPaXn0IZKJBECZjBVJyk/duce0jgqbQ7C
 PZz5j4C2xrPyu3Y98joj37HPEAHCy0DPRx2Es1mz5cHPzI1TDRClHzPrxyycz9gr
 D9WnMiPj9ff9aDaV6XpWKyuHhPxaHpoOD3VGdrhx6bU19Jd3/mLHB3lSt1kJzWdg
 QrSAk3KzMWAZigz/+I5xetOpbygKTPLEYgpdmdOSTrtACcm1wjnhIougu0FUIWXK
 arPNFOIV9liN0qCQyDOcLx4UEcxXrb2W0AYeHHJDBFxJ7sT2WWUCjPZFW5bh3G+Y
 goKv/XJRVWJxFlTXLZLZ5siclzzIlAAmSylh661ji836yRhqTQ3NJTB8QfnrGGsZ
 QlD1hjpyqC8uwIGUvoh56KdLRTxj9Gj70gpVe/Lk3Z16mivqDUE=
 =fSr0
 -----END PGP SIGNATURE-----

Merge tag 'afs-netfs-lib-20210426' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

Pull AFS updates from David Howells:
 "Use the new netfs lib.

  Begin the process of overhauling the use of the fscache API by AFS and
  the introduction of support for features such as Transparent Huge
  Pages (THPs).

   - Add some support for THPs, including using core VM helper functions
     to find details of pages.

   - Use the ITER_XARRAY I/O iterator to mediate access to the pagecache
     as this handles THPs and doesn't require allocation of large bvec
     arrays.

   - Delegate address_space read/pre-write I/O methods for AFS to the
     netfs helper library. A method is provided to the library that
     allows it to issue a read against the server.

     This includes a change in use for PG_fscache (it now indicates a
     DIO write in progress from the marked page), so a number of waits
     need to be deployed for it.

   - Split the core AFS writeback function to make it easier to modify
     in future patches to handle writing to the cache. [This might
     feasibly make more sense moved out into my fscache-iter branch].

  I've tested these with "xfstests -g quick" against an AFS volume
  (xfstests needs patching to make it work). With this, AFS without a
  cache passes all expected xfstests; with a cache, there's an extra
  failure, but that's also there before these patches. Fixing that
  probably requires a greater overhaul (as can be found on my
  fscache-iter branch, but that's for a later time).

  Thanks should go to Marc Dionne and Jeff Altman of AuriStor for
  exercising the patches in their test farm also"

Link: https://lore.kernel.org/lkml/3785063.1619482429@warthog.procyon.org.uk/

* tag 'afs-netfs-lib-20210426' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
  afs: Use the netfs_write_begin() helper
  afs: Use new netfs lib read helper API
  afs: Use the fs operation ops to handle FetchData completion
  afs: Prepare for use of THPs
  afs: Extract writeback extension into its own function
  afs: Wait on PG_fscache before modifying/releasing a page
  afs: Use ITER_XARRAY for writing
  afs: Set up the iov_iter before calling afs_extract_data()
  afs: Log remote unmarshalling errors
  afs: Don't truncate iter during data fetch
  afs: Move key to afs_read struct
  afs: Print the operation debug_id when logging an unexpected data version
  afs: Pass page into dirty region helpers to provide THP size
  afs: Disable use of the fscache I/O routines
2021-04-27 13:27:39 -07:00
Linus Torvalds
d1466bc583 Merge branch 'work.inode-type-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs inode type handling updates from Al Viro:
 "We should never change the type bits of ->i_mode or the method tables
  (->i_op and ->i_fop) of a live inode.

  Unfortunately, not all filesystems took care to prevent that"

* 'work.inode-type-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  spufs: fix bogosity in S_ISGID handling
  9p: missing chunk of "fs/9p: Don't update file type when updating file attributes"
  openpromfs: don't do unlock_new_inode() until the new inode is set up
  hostfs_mknod(): don't bother with init_special_inode()
  cifs: have cifs_fattr_to_inode() refuse to change type on live inode
  cifs: have ->mkdir() handle race with another client sanely
  do_cifs_create(): don't set ->i_mode of something we had not created
  gfs2: be careful with inode refresh
  ocfs2_inode_lock_update(): make sure we don't change the type bits of i_mode
  orangefs_inode_is_stale(): i_mode type bits do *not* form a bitmap...
  vboxsf: don't allow to change the inode type
  afs: Fix updating of i_mode due to 3rd party change
  ceph: don't allow type or device number to change on non-I_NEW inodes
  ceph: fix up error handling with snapdirs
  new helper: inode_wrong_type()
2021-04-27 10:57:42 -07:00
David Howells
3003bbd069 afs: Use the netfs_write_begin() helper
Make AFS use the new netfs_write_begin() helper to do the pre-reading
required before the write.  If successful, the helper returns with the
required page filled in and locked.  It may read more than just one page,
expanding the read to meet cache granularity requirements as necessary.

Note: A more advanced version of this could be made that does
generic_perform_write() for a whole cache granule.  This would make it
easier to avoid doing the download/read for the data to be overwritten.

Signed-off-by: David Howells <dhowells@redhat.com>
Tested-By: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
cc: linux-cachefs@redhat.com
cc: linux-fsdevel@vger.kernel.org
Link: https://lore.kernel.org/r/160588546422.3465195.1546354372589291098.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/161539563244.286939.16537296241609909980.stgit@warthog.procyon.org.uk/ # v4
Link: https://lore.kernel.org/r/161653819291.2770958.406013201547420544.stgit@warthog.procyon.org.uk/ # v5
Link: https://lore.kernel.org/r/161789102743.6155.17396591236631761195.stgit@warthog.procyon.org.uk/ # v6
2021-04-23 10:17:28 +01:00
David Howells
5cbf03985c afs: Use new netfs lib read helper API
Make AFS use the new netfs read helpers to implement the VM read
operations:

 - afs_readpage() now hands off responsibility to netfs_readpage().

 - afs_readpages() is gone and replaced with afs_readahead().

 - afs_readahead() just hands off responsibility to netfs_readahead().

These make use of the cache if a cookie is supplied, otherwise just call
the ->issue_op() method a sufficient number of times to complete the entire
request.

Changes:
v5:
- Use proper wait function for PG_fscache in afs_page_mkwrite()[1].
- Use killable wait for PG_writeback in afs_page_mkwrite()[1].

v4:
- Folded in error handling fixes to afs_req_issue_op().
- Added flag to netfs_subreq_terminated() to indicate that the caller may
  have been running async and stuff that might sleep needs punting to a
  workqueue.

Signed-off-by: David Howells <dhowells@redhat.com>
Tested-By: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
cc: linux-cachefs@redhat.com
cc: linux-fsdevel@vger.kernel.org
Link: https://lore.kernel.org/r/2499407.1616505440@warthog.procyon.org.uk [1]
Link: https://lore.kernel.org/r/160588542733.3465195.7526541422073350302.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/161118158436.1232039.3884845981224091996.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/161161053540.2537118.14904446369309535330.stgit@warthog.procyon.org.uk/ # v2
Link: https://lore.kernel.org/r/161340418739.1303470.5908092911600241280.stgit@warthog.procyon.org.uk/ # v3
Link: https://lore.kernel.org/r/161539561926.286939.5729036262354802339.stgit@warthog.procyon.org.uk/ # v4
Link: https://lore.kernel.org/r/161653817977.2770958.17696456811587237197.stgit@warthog.procyon.org.uk/ # v5
Link: https://lore.kernel.org/r/161789101258.6155.3879271028895121537.stgit@warthog.procyon.org.uk/ # v6
2021-04-23 10:17:28 +01:00
David Howells
dc4191841d afs: Use the fs operation ops to handle FetchData completion
Use the 'success' and 'aborted' afs_operations_ops methods and add a
'failed' method to handle the completion of an AFS.FetchData,
AFS.FetchData64 or YFS.FetchData64 RPC operation rather than directly
calling the done func pointed to by the afs_read struct from the call
delivery handler.

This means the done function will be called back on error also, not just on
successful completion.

This allows motion towards asynchronous data reception on data fetch calls
and allows any error to be handed off to the fscache read helper in the
same place as a successful completion.

Signed-off-by: David Howells <dhowells@redhat.com>
Tested-By: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
cc: linux-cachefs@redhat.com
cc: linux-fsdevel@vger.kernel.org
Link: https://lore.kernel.org/r/160588541471.3465195.8807019223378490810.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/161118157260.1232039.6549085372718234792.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/161161052647.2537118.12922380836599003659.stgit@warthog.procyon.org.uk/ # v2
Link: https://lore.kernel.org/r/161340417106.1303470.3502017303898569631.stgit@warthog.procyon.org.uk/ # v3
Link: https://lore.kernel.org/r/161539560673.286939.391310781674212229.stgit@warthog.procyon.org.uk/ # v4
Link: https://lore.kernel.org/r/161653816367.2770958.5856904574822446404.stgit@warthog.procyon.org.uk/ # v5
Link: https://lore.kernel.org/r/161789099994.6155.473719823490561190.stgit@warthog.procyon.org.uk/ # v6
2021-04-23 10:17:28 +01:00
David Howells
e87b03f583 afs: Prepare for use of THPs
As a prelude to supporting transparent huge pages, use thp_size() and
similar rather than PAGE_SIZE/SHIFT.

Further, try and frame everything in terms of file positions and lengths
rather than page indices and numbers of pages.

Signed-off-by: David Howells <dhowells@redhat.com>
Tested-By: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
cc: linux-cachefs@redhat.com
cc: linux-fsdevel@vger.kernel.org
Link: https://lore.kernel.org/r/160588540227.3465195.4752143929716269062.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/161118155821.1232039.540445038028845740.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/161161051439.2537118.15577827510426326534.stgit@warthog.procyon.org.uk/ # v2
Link: https://lore.kernel.org/r/161340415869.1303470.6040191748634322355.stgit@warthog.procyon.org.uk/ # v3
Link: https://lore.kernel.org/r/161539559365.286939.18344613540296085269.stgit@warthog.procyon.org.uk/ # v4
Link: https://lore.kernel.org/r/161653815142.2770958.454490670311230206.stgit@warthog.procyon.org.uk/ # v5
Link: https://lore.kernel.org/r/161789098713.6155.16394227991842480300.stgit@warthog.procyon.org.uk/ # v6
2021-04-23 10:17:27 +01:00
David Howells
810caa3e67 afs: Extract writeback extension into its own function
Extract writeback extension into its own function to break up the writeback
function a bit.

Signed-off-by: David Howells <dhowells@redhat.com>
Tested-By: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
cc: linux-cachefs@redhat.com
cc: linux-fsdevel@vger.kernel.org
Link: https://lore.kernel.org/r/160588538471.3465195.782513375683399583.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/161118154610.1232039.1765365632920504822.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/161161050546.2537118.2202554806419189453.stgit@warthog.procyon.org.uk/ # v2
Link: https://lore.kernel.org/r/161340414102.1303470.9078891484034668985.stgit@warthog.procyon.org.uk/ # v3
Link: https://lore.kernel.org/r/161539558417.286939.2879469588895925399.stgit@warthog.procyon.org.uk/ # v4
Link: https://lore.kernel.org/r/161653813972.2770958.12671731209438112378.stgit@warthog.procyon.org.uk/ # v5
Link: https://lore.kernel.org/r/161789097132.6155.4916609419912731964.stgit@warthog.procyon.org.uk/ # v6
2021-04-23 10:17:27 +01:00
David Howells
630f5dda84 afs: Wait on PG_fscache before modifying/releasing a page
PG_fscache is going to be used to indicate that a page is being written to
the cache, and that the page should not be modified or released until it's
finished.

Make afs_invalidatepage() and afs_releasepage() wait for it.

Signed-off-by: David Howells <dhowells@redhat.com>
Tested-By: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
cc: linux-cachefs@redhat.com
cc: linux-fsdevel@vger.kernel.org
Link: https://lore.kernel.org/r/158861253957.340223.7465334678444521655.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/159465832417.1377938.3571599385208729791.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/160588536286.3465195.13231895135369807920.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/161118153708.1232039.3535103645871176749.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/161161049369.2537118.11591934943429117060.stgit@warthog.procyon.org.uk/ # v2
Link: https://lore.kernel.org/r/161340412903.1303470.6424701655031380012.stgit@warthog.procyon.org.uk/ # v3
Link: https://lore.kernel.org/r/161539556890.286939.5873470593519458598.stgit@warthog.procyon.org.uk/ # v4
Link: https://lore.kernel.org/r/161653812726.2770958.18167145829938766503.stgit@warthog.procyon.org.uk/ # v5
Link: https://lore.kernel.org/r/161789096241.6155.5907241930823579235.stgit@warthog.procyon.org.uk/ # v6
2021-04-23 10:17:27 +01:00
David Howells
bd80d8a80e afs: Use ITER_XARRAY for writing
Use a single ITER_XARRAY iterator to describe the portion of a file to be
transmitted to the server rather than generating a series of small
ITER_BVEC iterators on the fly.  This will make it easier to implement AIO
in afs.

In theory we could maybe use one giant ITER_BVEC, but that means
potentially allocating a huge array of bio_vec structs (max 256 per page)
when in fact the pagecache already has a structure listing all the relevant
pages (radix_tree/xarray) that can be walked over.

Signed-off-by: David Howells <dhowells@redhat.com>
Tested-By: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
cc: linux-cachefs@redhat.com
cc: linux-fsdevel@vger.kernel.org
Link: https://lore.kernel.org/r/153685395197.14766.16289516750731233933.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/158861251312.340223.17924900795425422532.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/159465828607.1377938.6903132788463419368.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/160588535018.3465195.14509994354240338307.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/161118152415.1232039.6452879415814850025.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/161161048194.2537118.13763612220937637316.stgit@warthog.procyon.org.uk/ # v2
Link: https://lore.kernel.org/r/161340411602.1303470.4661108879482218408.stgit@warthog.procyon.org.uk/ # v3
Link: https://lore.kernel.org/r/161539555629.286939.5241869986617154517.stgit@warthog.procyon.org.uk/ # v4
Link: https://lore.kernel.org/r/161653811456.2770958.7017388543246759245.stgit@warthog.procyon.org.uk/ # v5
Link: https://lore.kernel.org/r/161789095005.6155.6789055030327407928.stgit@warthog.procyon.org.uk/ # v6
2021-04-23 10:17:27 +01:00
David Howells
c450846461 afs: Set up the iov_iter before calling afs_extract_data()
afs_extract_data() sets up a temporary iov_iter and passes it to AF_RXRPC
each time it is called to describe the remaining buffer to be filled.

Instead:

 (1) Put an iterator in the afs_call struct.

 (2) Set the iterator for each marshalling stage to load data into the
     appropriate places.  A number of convenience functions are provided to
     this end (eg. afs_extract_to_buf()).

     This iterator is then passed to afs_extract_data().

 (3) Use the new ITER_XARRAY iterator when reading data to load directly
     into the inode's pages without needing to create a list of them.

This will allow O_DIRECT calls to be supported in future patches.

Signed-off-by: David Howells <dhowells@redhat.com>
Tested-By: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
cc: linux-cachefs@redhat.com
cc: linux-fsdevel@vger.kernel.org
Link: https://lore.kernel.org/r/152898380012.11616.12094591785228251717.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/153685394431.14766.3178466345696987059.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/153999787395.866.11218209749223643998.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/154033911195.12041.3882700371848894587.stgit@warthog.procyon.org.uk/ # v2
Link: https://lore.kernel.org/r/158861250059.340223.1248231474865140653.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/159465827399.1377938.11181327349704960046.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/160588533776.3465195.3612752083351956948.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/161118151238.1232039.17015723405750601161.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/161161047240.2537118.14721975104810564022.stgit@warthog.procyon.org.uk/ # v2
Link: https://lore.kernel.org/r/161340410333.1303470.16260122230371140878.stgit@warthog.procyon.org.uk/ # v3
Link: https://lore.kernel.org/r/161539554187.286939.15305559004905459852.stgit@warthog.procyon.org.uk/ # v4
Link: https://lore.kernel.org/r/161653810525.2770958.4630666029125411789.stgit@warthog.procyon.org.uk/ # v5
Link: https://lore.kernel.org/r/161789093719.6155.7877160739235087723.stgit@warthog.procyon.org.uk/ # v6
2021-04-23 10:17:27 +01:00
David Howells
05092755aa afs: Log remote unmarshalling errors
Log unmarshalling errors reported by the peer (ie. it can't parse what we
sent it).  Limit the maximum number of messages to 3.

Signed-off-by: David Howells <dhowells@redhat.com>
Tested-By: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
cc: linux-cachefs@redhat.com
cc: linux-fsdevel@vger.kernel.org
Link: https://lore.kernel.org/r/159465826250.1377938.16372395422217583913.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/160588532584.3465195.15618385466614028590.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/161118149739.1232039.208060911149801695.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/161161046033.2537118.7779717661044373273.stgit@warthog.procyon.org.uk/ # v2
Link: https://lore.kernel.org/r/161340409118.1303470.17812607349396199116.stgit@warthog.procyon.org.uk/ # v3
Link: https://lore.kernel.org/r/161539552964.286939.16503232687974398308.stgit@warthog.procyon.org.uk/ # v4
Link: https://lore.kernel.org/r/161653808989.2770958.11530765353025697860.stgit@warthog.procyon.org.uk/ # v5
Link: https://lore.kernel.org/r/161789092349.6155.8581594259882708631.stgit@warthog.procyon.org.uk/ # v6
2021-04-23 10:17:26 +01:00
David Howells
f105da1a79 afs: Don't truncate iter during data fetch
Don't truncate the iterator to correspond to the actual data size when
fetching the data from the server - rather, pass the length we want to read
to rxrpc.

This will allow the clear-after-read code in future to simply clear the
remaining iterator capacity rather than having to reinitialise the
iterator.

Signed-off-by: David Howells <dhowells@redhat.com>
Tested-By: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
cc: linux-cachefs@redhat.com
cc: linux-fsdevel@vger.kernel.org
Link: https://lore.kernel.org/r/158861249201.340223.13035445866976590375.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/159465825061.1377938.14403904452300909320.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/160588531418.3465195.10712005940763063144.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/161118148567.1232039.13380313332292947956.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/161161044610.2537118.17908520793806837792.stgit@warthog.procyon.org.uk/ # v2
Link: https://lore.kernel.org/r/161340407907.1303470.6501394859511712746.stgit@warthog.procyon.org.uk/ # v3
Link: https://lore.kernel.org/r/161539551721.286939.14655713136572200716.stgit@warthog.procyon.org.uk/ # v4
Link: https://lore.kernel.org/r/161653807790.2770958.14034599989374173734.stgit@warthog.procyon.org.uk/ # v5
Link: https://lore.kernel.org/r/161789090823.6155.15673999934535049102.stgit@warthog.procyon.org.uk/ # v6
2021-04-23 10:17:26 +01:00
David Howells
c69bf479ba afs: Move key to afs_read struct
Stash the key used to authenticate read operations in the afs_read struct.
This will be necessary to reissue the operation against the server if a
read from the cache fails in upcoming cache changes.

Signed-off-by: David Howells <dhowells@redhat.com>
Tested-By: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
cc: linux-cachefs@redhat.com
cc: linux-fsdevel@vger.kernel.org
Link: https://lore.kernel.org/r/158861248336.340223.1851189950710196001.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/159465823899.1377938.11925978022348532049.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/160588529557.3465195.7303323479305254243.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/161118147693.1232039.13780672951838643842.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/161161043340.2537118.511899217704140722.stgit@warthog.procyon.org.uk/ # v2
Link: https://lore.kernel.org/r/161340406678.1303470.12676824086429446370.stgit@warthog.procyon.org.uk/ # v3
Link: https://lore.kernel.org/r/161539550819.286939.1268332875889175195.stgit@warthog.procyon.org.uk/ # v4
Link: https://lore.kernel.org/r/161653806683.2770958.11300984379283401542.stgit@warthog.procyon.org.uk/ # v5
Link: https://lore.kernel.org/r/161789089556.6155.14603302893431820997.stgit@warthog.procyon.org.uk/ # v6
2021-04-23 10:17:26 +01:00
David Howells
f015cf1d6b afs: Print the operation debug_id when logging an unexpected data version
Print the afs_operation debug_id when logging an unexpected change in the
data version.  This allows the logged message to be matched against
tracelines.

Signed-off-by: David Howells <dhowells@redhat.com>
Tested-By: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
cc: linux-cachefs@redhat.com
cc: linux-fsdevel@vger.kernel.org
Link: https://lore.kernel.org/r/160588528377.3465195.2206051235095182302.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/161118146111.1232039.11398082422487058312.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/161161042180.2537118.2471333561661033316.stgit@warthog.procyon.org.uk/ # v2
Link: https://lore.kernel.org/r/161340405772.1303470.3877167548944248214.stgit@warthog.procyon.org.uk/ # v3
Link: https://lore.kernel.org/r/161539549628.286939.15234870409714613954.stgit@warthog.procyon.org.uk/ # v4
Link: https://lore.kernel.org/r/161653805530.2770958.15120507632529970934.stgit@warthog.procyon.org.uk/ # v5
Link: https://lore.kernel.org/r/161789088290.6155.3494369629853673866.stgit@warthog.procyon.org.uk/ # v6
2021-04-23 10:17:26 +01:00
David Howells
67d78a6f6e afs: Pass page into dirty region helpers to provide THP size
Pass a pointer to the page being accessed into the dirty region helpers so
that the size of the page can be determined in case it's a transparent huge
page.

This also required the page to be passed into the afs_page_dirty trace
point - so there's no need to specifically pass in the index or private
data as these can be retrieved directly from the page struct.

Signed-off-by: David Howells <dhowells@redhat.com>
Tested-By: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
cc: linux-cachefs@redhat.com
cc: linux-fsdevel@vger.kernel.org
Link: https://lore.kernel.org/r/160588527183.3465195.16107942526481976308.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/161118144921.1232039.11377711180492625929.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/161161040747.2537118.11435394902674511430.stgit@warthog.procyon.org.uk/ # v2
Link: https://lore.kernel.org/r/161340404553.1303470.11414163641767769882.stgit@warthog.procyon.org.uk/ # v3
Link: https://lore.kernel.org/r/161539548385.286939.8864598314493255313.stgit@warthog.procyon.org.uk/ # v4
Link: https://lore.kernel.org/r/161653804285.2770958.3497360004849598038.stgit@warthog.procyon.org.uk/ # v5
Link: https://lore.kernel.org/r/161789087043.6155.16922142208140170528.stgit@warthog.procyon.org.uk/ # v6
2021-04-23 10:17:26 +01:00
David Howells
03ffae9092 afs: Disable use of the fscache I/O routines
Disable use of the fscache I/O routined by the AFS filesystem.  It's about
to transition to passing iov_iters down and fscache is about to have its
I/O path to use iov_iter, so all that needs to change.

Signed-off-by: David Howells <dhowells@redhat.com>
Tested-By: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
cc: linux-cachefs@redhat.com
cc: linux-fsdevel@vger.kernel.org
Link: https://lore.kernel.org/r/158861209824.340223.1864211542341758994.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/159465768717.1376105.2229314852486665807.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/160588457929.3465195.1730097418904945578.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/161118143744.1232039.2727898205333669064.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/161161039077.2537118.7986870854927176905.stgit@warthog.procyon.org.uk/ # v2
Link: https://lore.kernel.org/r/161340403323.1303470.8159439948319423431.stgit@warthog.procyon.org.uk/ # v3
Link: https://lore.kernel.org/r/161539547167.286939.3536238932531122332.stgit@warthog.procyon.org.uk/ # v4
Link: https://lore.kernel.org/r/161653802797.2770958.547311814861545911.stgit@warthog.procyon.org.uk/ # v5
Link: https://lore.kernel.org/r/161789085806.6155.2596146255056027428.stgit@warthog.procyon.org.uk/ # v6
2021-04-23 10:17:25 +01:00
Matthew Wilcox (Oracle)
75b6979961 afs: Use wait_on_page_writeback_killable
Open-coding this function meant it missed out on the recent bugfix
for waiters being woken by a delayed wake event from a previous
instantiation of the page[1].

[DH: Changed the patch to use vmf->page rather than variable page which
 doesn't exist yet upstream]

Fixes: 1cf7a1518a ("afs: Implement shared-writeable mmap")
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: kafs-testing@auristor.com
cc: linux-afs@lists.infradead.org
cc: linux-mm@kvack.org
Link: https://lore.kernel.org/r/20210320054104.1300774-4-willy@infradead.org
Link: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=c2407cf7d22d0c0d94cf20342b3b8f06f1d904e7 [1]
2021-03-23 20:54:37 +00:00
David Howells
a7889c6320 afs: Stop listxattr() from listing "afs.*" attributes
afs_listxattr() lists all the available special afs xattrs (i.e. those in
the "afs.*" space), no matter what type of server we're dealing with.  But
OpenAFS servers, for example, cannot deal with some of the extra-capable
attributes that AuriStor (YFS) servers provide.  Unfortunately, the
presence of the afs.yfs.* attributes causes errors[1] for anything that
tries to read them if the server is of the wrong type.

Fix the problem by removing afs_listxattr() so that none of the special
xattrs are listed (AFS doesn't support xattrs).  It does mean, however,
that getfattr won't list them, though they can still be accessed with
getxattr() and setxattr().

This can be tested with something like:

	getfattr -d -m ".*" /afs/example.com/path/to/file

With this change, none of the afs.* attributes should be visible.

Changes:
ver #2:
 - Hide all of the afs.* xattrs, not just the ACL ones.

Fixes: ae46578b96 ("afs: Get YFS ACLs and information through xattrs")
Reported-by: Gaja Sophie Peters <gaja.peters@math.uni-hamburg.de>
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Gaja Sophie Peters <gaja.peters@math.uni-hamburg.de>
Reviewed-by: Jeffrey Altman <jaltman@auristor.com>
Reviewed-by: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
Link: http://lists.infradead.org/pipermail/linux-afs/2021-March/003502.html [1]
Link: http://lists.infradead.org/pipermail/linux-afs/2021-March/003567.html # v1
Link: http://lists.infradead.org/pipermail/linux-afs/2021-March/003573.html # v2
2021-03-15 17:09:54 +00:00
David Howells
64fcbb6158 afs: Fix accessing YFS xattrs on a non-YFS server
If someone attempts to access YFS-related xattrs (e.g. afs.yfs.acl) on a
file on a non-YFS AFS server (such as OpenAFS), then the kernel will jump
to a NULL function pointer because the afs_fetch_acl_operation descriptor
doesn't point to a function for issuing an operation on a non-YFS
server[1].

Fix this by making afs_wait_for_operation() check that the issue_afs_rpc
method is set before jumping to it and setting -ENOTSUPP if not.  This fix
also covers other potential operations that also only exist on YFS servers.

afs_xattr_get/set_yfs() then need to translate -ENOTSUPP to -ENODATA as the
former error is internal to the kernel.

The bug shows up as an oops like the following:

	BUG: kernel NULL pointer dereference, address: 0000000000000000
	[...]
	Code: Unable to access opcode bytes at RIP 0xffffffffffffffd6.
	[...]
	Call Trace:
	 afs_wait_for_operation+0x83/0x1b0 [kafs]
	 afs_xattr_get_yfs+0xe6/0x270 [kafs]
	 __vfs_getxattr+0x59/0x80
	 vfs_getxattr+0x11c/0x140
	 getxattr+0x181/0x250
	 ? __check_object_size+0x13f/0x150
	 ? __fput+0x16d/0x250
	 __x64_sys_fgetxattr+0x64/0xb0
	 do_syscall_64+0x49/0xc0
	 entry_SYSCALL_64_after_hwframe+0x44/0xa9
	RIP: 0033:0x7fb120a9defe

This was triggered with "cp -a" which attempts to copy xattrs, including
afs ones, but is easier to reproduce with getfattr, e.g.:

	getfattr -d -m ".*" /afs/openafs.org/

Fixes: e49c7b2f6d ("afs: Build an abstraction around an "operation" concept")
Reported-by: Gaja Sophie Peters <gaja.peters@math.uni-hamburg.de>
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Gaja Sophie Peters <gaja.peters@math.uni-hamburg.de>
Reviewed-by: Marc Dionne <marc.dionne@auristor.com>
Reviewed-by: Jeffrey Altman <jaltman@auristor.com>
cc: linux-afs@lists.infradead.org
Link: http://lists.infradead.org/pipermail/linux-afs/2021-March/003498.html [1]
Link: http://lists.infradead.org/pipermail/linux-afs/2021-March/003566.html # v1
Link: http://lists.infradead.org/pipermail/linux-afs/2021-March/003572.html # v2
2021-03-15 17:01:18 +00:00
David Howells
6e1eb04a87 afs: Fix updating of i_mode due to 3rd party change
Fix afs_apply_status() to mask off the irrelevant bits from status->mode
when OR'ing them into i_mode.  This can happen when a 3rd party chmod
occurs.

Also fix afs_inode_init_from_status() to mask off the mode bits when
initialising i_mode.

Fixes: 260a980317 ("[AFS]: Add "directory write" support.")
Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2021-03-08 10:19:37 -05:00
Linus Torvalds
7d6beb71da idmapped-mounts-v5.12
-----BEGIN PGP SIGNATURE-----
 
 iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCYCegywAKCRCRxhvAZXjc
 ouJ6AQDlf+7jCQlQdeKKoN9QDFfMzG1ooemat36EpRRTONaGuAD8D9A4sUsG4+5f
 4IU5Lj9oY4DEmF8HenbWK2ZHsesL2Qg=
 =yPaw
 -----END PGP SIGNATURE-----

Merge tag 'idmapped-mounts-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux

Pull idmapped mounts from Christian Brauner:
 "This introduces idmapped mounts which has been in the making for some
  time. Simply put, different mounts can expose the same file or
  directory with different ownership. This initial implementation comes
  with ports for fat, ext4 and with Christoph's port for xfs with more
  filesystems being actively worked on by independent people and
  maintainers.

  Idmapping mounts handle a wide range of long standing use-cases. Here
  are just a few:

   - Idmapped mounts make it possible to easily share files between
     multiple users or multiple machines especially in complex
     scenarios. For example, idmapped mounts will be used in the
     implementation of portable home directories in
     systemd-homed.service(8) where they allow users to move their home
     directory to an external storage device and use it on multiple
     computers where they are assigned different uids and gids. This
     effectively makes it possible to assign random uids and gids at
     login time.

   - It is possible to share files from the host with unprivileged
     containers without having to change ownership permanently through
     chown(2).

   - It is possible to idmap a container's rootfs and without having to
     mangle every file. For example, Chromebooks use it to share the
     user's Download folder with their unprivileged containers in their
     Linux subsystem.

   - It is possible to share files between containers with
     non-overlapping idmappings.

   - Filesystem that lack a proper concept of ownership such as fat can
     use idmapped mounts to implement discretionary access (DAC)
     permission checking.

   - They allow users to efficiently changing ownership on a per-mount
     basis without having to (recursively) chown(2) all files. In
     contrast to chown (2) changing ownership of large sets of files is
     instantenous with idmapped mounts. This is especially useful when
     ownership of a whole root filesystem of a virtual machine or
     container is changed. With idmapped mounts a single syscall
     mount_setattr syscall will be sufficient to change the ownership of
     all files.

   - Idmapped mounts always take the current ownership into account as
     idmappings specify what a given uid or gid is supposed to be mapped
     to. This contrasts with the chown(2) syscall which cannot by itself
     take the current ownership of the files it changes into account. It
     simply changes the ownership to the specified uid and gid. This is
     especially problematic when recursively chown(2)ing a large set of
     files which is commong with the aforementioned portable home
     directory and container and vm scenario.

   - Idmapped mounts allow to change ownership locally, restricting it
     to specific mounts, and temporarily as the ownership changes only
     apply as long as the mount exists.

  Several userspace projects have either already put up patches and
  pull-requests for this feature or will do so should you decide to pull
  this:

   - systemd: In a wide variety of scenarios but especially right away
     in their implementation of portable home directories.

         https://systemd.io/HOME_DIRECTORY/

   - container runtimes: containerd, runC, LXD:To share data between
     host and unprivileged containers, unprivileged and privileged
     containers, etc. The pull request for idmapped mounts support in
     containerd, the default Kubernetes runtime is already up for quite
     a while now: https://github.com/containerd/containerd/pull/4734

   - The virtio-fs developers and several users have expressed interest
     in using this feature with virtual machines once virtio-fs is
     ported.

   - ChromeOS: Sharing host-directories with unprivileged containers.

  I've tightly synced with all those projects and all of those listed
  here have also expressed their need/desire for this feature on the
  mailing list. For more info on how people use this there's a bunch of
  talks about this too. Here's just two recent ones:

      https://www.cncf.io/wp-content/uploads/2020/12/Rootless-Containers-in-Gitpod.pdf
      https://fosdem.org/2021/schedule/event/containers_idmap/

  This comes with an extensive xfstests suite covering both ext4 and
  xfs:

      https://git.kernel.org/brauner/xfstests-dev/h/idmapped_mounts

  It covers truncation, creation, opening, xattrs, vfscaps, setid
  execution, setgid inheritance and more both with idmapped and
  non-idmapped mounts. It already helped to discover an unrelated xfs
  setgid inheritance bug which has since been fixed in mainline. It will
  be sent for inclusion with the xfstests project should you decide to
  merge this.

  In order to support per-mount idmappings vfsmounts are marked with
  user namespaces. The idmapping of the user namespace will be used to
  map the ids of vfs objects when they are accessed through that mount.
  By default all vfsmounts are marked with the initial user namespace.
  The initial user namespace is used to indicate that a mount is not
  idmapped. All operations behave as before and this is verified in the
  testsuite.

  Based on prior discussions we want to attach the whole user namespace
  and not just a dedicated idmapping struct. This allows us to reuse all
  the helpers that already exist for dealing with idmappings instead of
  introducing a whole new range of helpers. In addition, if we decide in
  the future that we are confident enough to enable unprivileged users
  to setup idmapped mounts the permission checking can take into account
  whether the caller is privileged in the user namespace the mount is
  currently marked with.

  The user namespace the mount will be marked with can be specified by
  passing a file descriptor refering to the user namespace as an
  argument to the new mount_setattr() syscall together with the new
  MOUNT_ATTR_IDMAP flag. The system call follows the openat2() pattern
  of extensibility.

  The following conditions must be met in order to create an idmapped
  mount:

   - The caller must currently have the CAP_SYS_ADMIN capability in the
     user namespace the underlying filesystem has been mounted in.

   - The underlying filesystem must support idmapped mounts.

   - The mount must not already be idmapped. This also implies that the
     idmapping of a mount cannot be altered once it has been idmapped.

   - The mount must be a detached/anonymous mount, i.e. it must have
     been created by calling open_tree() with the OPEN_TREE_CLONE flag
     and it must not already have been visible in the filesystem.

  The last two points guarantee easier semantics for userspace and the
  kernel and make the implementation significantly simpler.

  By default vfsmounts are marked with the initial user namespace and no
  behavioral or performance changes are observed.

  The manpage with a detailed description can be found here:

      1d7b902e28

  In order to support idmapped mounts, filesystems need to be changed
  and mark themselves with the FS_ALLOW_IDMAP flag in fs_flags. The
  patches to convert individual filesystem are not very large or
  complicated overall as can be seen from the included fat, ext4, and
  xfs ports. Patches for other filesystems are actively worked on and
  will be sent out separately. The xfstestsuite can be used to verify
  that port has been done correctly.

  The mount_setattr() syscall is motivated independent of the idmapped
  mounts patches and it's been around since July 2019. One of the most
  valuable features of the new mount api is the ability to perform
  mounts based on file descriptors only.

  Together with the lookup restrictions available in the openat2()
  RESOLVE_* flag namespace which we added in v5.6 this is the first time
  we are close to hardened and race-free (e.g. symlinks) mounting and
  path resolution.

  While userspace has started porting to the new mount api to mount
  proper filesystems and create new bind-mounts it is currently not
  possible to change mount options of an already existing bind mount in
  the new mount api since the mount_setattr() syscall is missing.

  With the addition of the mount_setattr() syscall we remove this last
  restriction and userspace can now fully port to the new mount api,
  covering every use-case the old mount api could. We also add the
  crucial ability to recursively change mount options for a whole mount
  tree, both removing and adding mount options at the same time. This
  syscall has been requested multiple times by various people and
  projects.

  There is a simple tool available at

      https://github.com/brauner/mount-idmapped

  that allows to create idmapped mounts so people can play with this
  patch series. I'll add support for the regular mount binary should you
  decide to pull this in the following weeks:

  Here's an example to a simple idmapped mount of another user's home
  directory:

	u1001@f2-vm:/$ sudo ./mount --idmap both:1000:1001:1 /home/ubuntu/ /mnt

	u1001@f2-vm:/$ ls -al /home/ubuntu/
	total 28
	drwxr-xr-x 2 ubuntu ubuntu 4096 Oct 28 22:07 .
	drwxr-xr-x 4 root   root   4096 Oct 28 04:00 ..
	-rw------- 1 ubuntu ubuntu 3154 Oct 28 22:12 .bash_history
	-rw-r--r-- 1 ubuntu ubuntu  220 Feb 25  2020 .bash_logout
	-rw-r--r-- 1 ubuntu ubuntu 3771 Feb 25  2020 .bashrc
	-rw-r--r-- 1 ubuntu ubuntu  807 Feb 25  2020 .profile
	-rw-r--r-- 1 ubuntu ubuntu    0 Oct 16 16:11 .sudo_as_admin_successful
	-rw------- 1 ubuntu ubuntu 1144 Oct 28 00:43 .viminfo

	u1001@f2-vm:/$ ls -al /mnt/
	total 28
	drwxr-xr-x  2 u1001 u1001 4096 Oct 28 22:07 .
	drwxr-xr-x 29 root  root  4096 Oct 28 22:01 ..
	-rw-------  1 u1001 u1001 3154 Oct 28 22:12 .bash_history
	-rw-r--r--  1 u1001 u1001  220 Feb 25  2020 .bash_logout
	-rw-r--r--  1 u1001 u1001 3771 Feb 25  2020 .bashrc
	-rw-r--r--  1 u1001 u1001  807 Feb 25  2020 .profile
	-rw-r--r--  1 u1001 u1001    0 Oct 16 16:11 .sudo_as_admin_successful
	-rw-------  1 u1001 u1001 1144 Oct 28 00:43 .viminfo

	u1001@f2-vm:/$ touch /mnt/my-file

	u1001@f2-vm:/$ setfacl -m u:1001:rwx /mnt/my-file

	u1001@f2-vm:/$ sudo setcap -n 1001 cap_net_raw+ep /mnt/my-file

	u1001@f2-vm:/$ ls -al /mnt/my-file
	-rw-rwxr--+ 1 u1001 u1001 0 Oct 28 22:14 /mnt/my-file

	u1001@f2-vm:/$ ls -al /home/ubuntu/my-file
	-rw-rwxr--+ 1 ubuntu ubuntu 0 Oct 28 22:14 /home/ubuntu/my-file

	u1001@f2-vm:/$ getfacl /mnt/my-file
	getfacl: Removing leading '/' from absolute path names
	# file: mnt/my-file
	# owner: u1001
	# group: u1001
	user::rw-
	user:u1001:rwx
	group::rw-
	mask::rwx
	other::r--

	u1001@f2-vm:/$ getfacl /home/ubuntu/my-file
	getfacl: Removing leading '/' from absolute path names
	# file: home/ubuntu/my-file
	# owner: ubuntu
	# group: ubuntu
	user::rw-
	user:ubuntu:rwx
	group::rw-
	mask::rwx
	other::r--"

* tag 'idmapped-mounts-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux: (41 commits)
  xfs: remove the possibly unused mp variable in xfs_file_compat_ioctl
  xfs: support idmapped mounts
  ext4: support idmapped mounts
  fat: handle idmapped mounts
  tests: add mount_setattr() selftests
  fs: introduce MOUNT_ATTR_IDMAP
  fs: add mount_setattr()
  fs: add attr_flags_to_mnt_flags helper
  fs: split out functions to hold writers
  namespace: only take read lock in do_reconfigure_mnt()
  mount: make {lock,unlock}_mount_hash() static
  namespace: take lock_mount_hash() directly when changing flags
  nfs: do not export idmapped mounts
  overlayfs: do not mount on top of idmapped mounts
  ecryptfs: do not mount on top of idmapped mounts
  ima: handle idmapped mounts
  apparmor: handle idmapped mounts
  fs: make helpers idmap mount aware
  exec: handle idmapped mounts
  would_dump: handle idmapped mounts
  ...
2021-02-23 13:39:45 -08:00
David Howells
5399d52233 rxrpc: Fix deadlock around release of dst cached on udp tunnel
AF_RXRPC sockets use UDP ports in encap mode.  This causes socket and dst
from an incoming packet to get stolen and attached to the UDP socket from
whence it is leaked when that socket is closed.

When a network namespace is removed, the wait for dst records to be cleaned
up happens before the cleanup of the rxrpc and UDP socket, meaning that the
wait never finishes.

Fix this by moving the rxrpc (and, by dependence, the afs) private
per-network namespace registrations to the device group rather than subsys
group.  This allows cached rxrpc local endpoints to be cleared and their
UDP sockets closed before we try waiting for the dst records.

The symptom is that lines looking like the following:

	unregister_netdevice: waiting for lo to become free

get emitted at regular intervals after running something like the
referenced syzbot test.

Thanks to Vadim for tracking this down and work out the fix.

Reported-by: syzbot+df400f2f24a1677cd7e0@syzkaller.appspotmail.com
Reported-by: Vadim Fedorenko <vfedorenko@novek.ru>
Fixes: 5271953cad ("rxrpc: Use the UDP encap_rcv hook")
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Vadim Fedorenko <vfedorenko@novek.ru>
Link: https://lore.kernel.org/r/161196443016.3868642.5577440140646403533.stgit@warthog.procyon.org.uk
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-29 21:38:11 -08:00
Christian Brauner
549c729771
fs: make helpers idmap mount aware
Extend some inode methods with an additional user namespace argument. A
filesystem that is aware of idmapped mounts will receive the user
namespace the mount has been marked with. This can be used for
additional permission checking and also to enable filesystems to
translate between uids and gids if they need to. We have implemented all
relevant helpers in earlier patches.

As requested we simply extend the exisiting inode method instead of
introducing new ones. This is a little more code churn but it's mostly
mechanical and doesnt't leave us with additional inode methods.

Link: https://lore.kernel.org/r/20210121131959.646623-25-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2021-01-24 14:27:20 +01:00
Christian Brauner
0d56a4518d
stat: handle idmapped mounts
The generic_fillattr() helper fills in the basic attributes associated
with an inode. Enable it to handle idmapped mounts. If the inode is
accessed through an idmapped mount map it into the mount's user
namespace before we store the uid and gid. If the initial user namespace
is passed nothing changes so non-idmapped mounts will see identical
behavior as before.

Link: https://lore.kernel.org/r/20210121131959.646623-12-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2021-01-24 14:27:17 +01:00
Christian Brauner
e65ce2a50c
acl: handle idmapped mounts
The posix acl permission checking helpers determine whether a caller is
privileged over an inode according to the acls associated with the
inode. Add helpers that make it possible to handle acls on idmapped
mounts.

The vfs and the filesystems targeted by this first iteration make use of
posix_acl_fix_xattr_from_user() and posix_acl_fix_xattr_to_user() to
translate basic posix access and default permissions such as the
ACL_USER and ACL_GROUP type according to the initial user namespace (or
the superblock's user namespace) to and from the caller's current user
namespace. Adapt these two helpers to handle idmapped mounts whereby we
either map from or into the mount's user namespace depending on in which
direction we're translating.
Similarly, cap_convert_nscap() is used by the vfs to translate user
namespace and non-user namespace aware filesystem capabilities from the
superblock's user namespace to the caller's user namespace. Enable it to
handle idmapped mounts by accounting for the mount's user namespace.

In addition the fileystems targeted in the first iteration of this patch
series make use of the posix_acl_chmod() and, posix_acl_update_mode()
helpers. Both helpers perform permission checks on the target inode. Let
them handle idmapped mounts. These two helpers are called when posix
acls are set by the respective filesystems to handle this case we extend
the ->set() method to take an additional user namespace argument to pass
the mount's user namespace down.

Link: https://lore.kernel.org/r/20210121131959.646623-9-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2021-01-24 14:27:17 +01:00
David Howells
366911cd76 afs: Fix directory entry size calculation
The number of dirent records used by an AFS directory entry should be
calculated using the assumption that there is a 16-byte name field in the
first block, rather than a 20-byte name field (which is actually the case).
This miscalculation is historic and effectively standard, so we have to use
it.

The calculation we need to use is:

	1 + (((strlen(name) + 1) + 15) >> 5)

where we are adding one to the strlen() result to account for the NUL
termination.

Fix this by the following means:

 (1) Create an inline function to do the calculation for a given name
     length.

 (2) Use the function to calculate the number of records used for a dirent
     in afs_dir_iterate_block().

     Use this to move the over-end check out of the loop since it only
     needs to be done once.

     Further use this to only go through the loop for the 2nd+ records
     composing an entry.  The only test there now is for if the record is
     allocated - and we already checked the first block at the top of the
     outer loop.

 (3) Add a max name length check in afs_dir_iterate_block().

 (4) Make afs_edit_dir_add() and afs_edit_dir_remove() use the function
     from (1) to calculate the number of blocks rather than doing it
     incorrectly themselves.

Fixes: 63a4681ff3 ("afs: Locally edit directory data for mkdir/create/unlink/...")
Fixes: ^1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Marc Dionne <marc.dionne@auristor.com>
2021-01-04 12:25:19 +00:00
David Howells
26982a89ca afs: Work around strnlen() oops with CONFIG_FORTIFIED_SOURCE=y
AFS has a structured layout in its directory contents (AFS dirs are
downloaded as files and parsed locally by the client for lookup/readdir).
The slots in the directory are defined by union afs_xdr_dirent.  This,
however, only directly allows a name of a length that will fit into that
union.  To support a longer name, the next 1-8 contiguous entries are
annexed to the first one and the name flows across these.

afs_dir_iterate_block() uses strnlen(), limited to the space to the end of
the page, to find out how long the name is.  This worked fine until
6a39e62abb.  With that commit, the compiler determines the size of the
array and asserts that the string fits inside that array.  This is a
problem for AFS because we *expect* it to overflow one or more arrays.

A similar problem also occurs in afs_dir_scan_block() when a directory file
is being locally edited to avoid the need to redownload it.  There strlen()
was being used safely because each page has the last byte set to 0 when the
file is downloaded and validated (in afs_dir_check_page()).

Fix this by changing the afs_xdr_dirent union name field to an
indeterminate-length array and dropping the overflow field.

(Note that whilst looking at this, I realised that the calculation of the
number of slots a dirent used is non-standard and not quite right, but I'll
address that in a separate patch.)

The issue can be triggered by something like:

        touch /afs/example.com/thisisaveryveryverylongname

and it generates a report that looks like:

        detected buffer overflow in strnlen
        ------------[ cut here ]------------
        kernel BUG at lib/string.c:1149!
        ...
        RIP: 0010:fortify_panic+0xf/0x11
        ...
        Call Trace:
         afs_dir_iterate_block+0x12b/0x35b
         afs_dir_iterate+0x14e/0x1ce
         afs_do_lookup+0x131/0x417
         afs_lookup+0x24f/0x344
         lookup_open.isra.0+0x1bb/0x27d
         open_last_lookups+0x166/0x237
         path_openat+0xe0/0x159
         do_filp_open+0x48/0xa4
         ? kmem_cache_alloc+0xf5/0x16e
         ? __clear_close_on_exec+0x13/0x22
         ? _raw_spin_unlock+0xa/0xb
         do_sys_openat2+0x72/0xde
         do_sys_open+0x3b/0x58
         do_syscall_64+0x2d/0x3a
         entry_SYSCALL_64_after_hwframe+0x44/0xa9

Fixes: 6a39e62abb ("lib: string.h: detect intra-object overflow in fortified string functions")
Reported-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Marc Dionne <marc.dionne@auristor.com>
cc: Daniel Axtens <dja@axtens.net>
2021-01-04 12:25:19 +00:00
David Howells
4cb6829647 afs: Fix memory leak when mounting with multiple source parameters
There's a memory leak in afs_parse_source() whereby multiple source=
parameters overwrite fc->source in the fs_context struct without freeing
the previously recorded source.

Fix this by only permitting a single source parameter and rejecting with
an error all subsequent ones.

This was caught by syzbot with the kernel memory leak detector, showing
something like the following trace:

  unreferenced object 0xffff888114375440 (size 32):
    comm "repro", pid 5168, jiffies 4294923723 (age 569.948s)
    backtrace:
      slab_post_alloc_hook+0x42/0x79
      __kmalloc_track_caller+0x125/0x16a
      kmemdup_nul+0x24/0x3c
      vfs_parse_fs_string+0x5a/0xa1
      generic_parse_monolithic+0x9d/0xc5
      do_new_mount+0x10d/0x15a
      do_mount+0x5f/0x8e
      __do_sys_mount+0xff/0x127
      do_syscall_64+0x2d/0x3a
      entry_SYSCALL_64_after_hwframe+0x44/0xa9

Fixes: 13fcc68370 ("afs: Add fs_context support")
Reported-by: syzbot+86dc6632faaca40133ab@syzkaller.appspotmail.com
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-08 15:59:25 -08:00
David Howells
a9e5c87ca7 afs: Fix speculative status fetch going out of order wrt to modifications
When doing a lookup in a directory, the afs filesystem uses a bulk
status fetch to speculatively retrieve the statuses of up to 48 other
vnodes found in the same directory and it will then either update extant
inodes or create new ones - effectively doing 'lookup ahead'.

To avoid the possibility of deadlocking itself, however, the filesystem
doesn't lock all of those inodes; rather just the directory inode is
locked (by the VFS).

When the operation completes, afs_inode_init_from_status() or
afs_apply_status() is called, depending on whether the inode already
exists, to commit the new status.

A case exists, however, where the speculative status fetch operation may
straddle a modification operation on one of those vnodes.  What can then
happen is that the speculative bulk status RPC retrieves the old status,
and whilst that is happening, the modification happens - which returns
an updated status, then the modification status is committed, then we
attempt to commit the speculative status.

This results in something like the following being seen in dmesg:

	kAFS: vnode modified {100058:861} 8->9 YFS.InlineBulkStatus

showing that for vnode 861 on volume 100058, we saw YFS.InlineBulkStatus
say that the vnode had data version 8 when we'd already recorded version
9 due to a local modification.  This was causing the cache to be
invalidated for that vnode when it shouldn't have been.  If it happens
on a data file, this might lead to local changes being lost.

Fix this by ignoring speculative status updates if the data version
doesn't match the expected value.

Note that it is possible to get a DV regression if a volume gets
restored from a backup - but we should get a callback break in such a
case that should trigger a recheck anyway.  It might be worth checking
the volume creation time in the volsync info and, if a change is
observed in that (as would happen on a restore), invalidate all caches
associated with the volume.

Fixes: 5cf9dd55a0 ("afs: Prospectively look up extra files when doing a single lookup")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-11-22 11:27:03 -08:00
David Howells
3ad216ee73 afs: Fix afs_write_end() when called with copied == 0 [ver #3]
When afs_write_end() is called with copied == 0, it tries to set the
dirty region, but there's no way to actually encode a 0-length region in
the encoding in page->private.

"0,0", for example, indicates a 1-byte region at offset 0.  The maths
miscalculates this and sets it incorrectly.

Fix it to just do nothing but unlock and put the page in this case.  We
don't actually need to mark the page dirty as nothing presumably
changed.

Fixes: 65dd2d6072 ("afs: Alter dirty range encoding in page->private")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-11-14 11:51:18 -08:00
David Howells
f4c79144ed afs: Fix incorrect freeing of the ACL passed to the YFS ACL store op
The cleanup for the yfs_store_opaque_acl2_operation calls the wrong
function to destroy the ACL content buffer.  It's an afs_acl struct, not
a yfs_acl struct - and the free function for latter may pass invalid
pointers to kfree().

Fix this by using the afs_acl_put() function.  The yfs_acl_put()
function is then no longer used and can be removed.

	general protection fault, probably for non-canonical address 0x7ebde00000000: 0000 [#1] SMP PTI
	...
	RIP: 0010:compound_head+0x0/0x11
	...
	Call Trace:
	 virt_to_cache+0x8/0x51
	 kfree+0x5d/0x79
	 yfs_free_opaque_acl+0x16/0x29
	 afs_put_operation+0x60/0x114
	 __vfs_setxattr+0x67/0x72
	 __vfs_setxattr_noperm+0x66/0xe9
	 vfs_setxattr+0x67/0xce
	 setxattr+0x14e/0x184
	 __do_sys_fsetxattr+0x66/0x8f
	 do_syscall_64+0x2d/0x3a
	 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Fixes: e49c7b2f6d ("afs: Build an abstraction around an "operation" concept")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-11-03 09:53:40 -08:00
David Howells
c80afa1d9c afs: Fix warning due to unadvanced marshalling pointer
When using the afs.yfs.acl xattr to change an AuriStor ACL, a warning
can be generated when the request is marshalled because the buffer
pointer isn't increased after adding the last element, thereby
triggering the check at the end if the ACL wasn't empty.  This just
causes something like the following warning, but doesn't stop the call
from happening successfully:

    kAFS: YFS.StoreOpaqueACL2: Request buffer underflow (36<108)

Fix this simply by increasing the count prior to the check.

Fixes: f5e4546347 ("afs: Implement YFS ACL setting")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-11-03 09:53:40 -08:00
David Howells
2d9900f26a afs: Fix dirty-region encoding on ppc32 with 64K pages
The dirty region bounds stored in page->private on an afs page are 15 bits
on a 32-bit box and can, at most, represent a range of up to 32K within a
32K page with a resolution of 1 byte.  This is a problem for powerpc32 with
64K pages enabled.

Further, transparent huge pages may get up to 2M, which will be a problem
for the afs filesystem on all 32-bit arches in the future.

Fix this by decreasing the resolution.  For the moment, a 64K page will
have a resolution determined from PAGE_SIZE.  In the future, the page will
need to be passed in to the helper functions so that the page size can be
assessed and the resolution determined dynamically.

Note that this might not be the ideal way to handle this, since it may
allow some leakage of undirtied zero bytes to the server's copy in the case
of a 3rd-party conflict.  Fixing that would require a separately allocated
record and is a more complicated fix.

Fixes: 4343d00872 ("afs: Get rid of the afs_writeback record")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
2020-10-29 13:53:04 +00:00
David Howells
f86726a69d afs: Fix afs_invalidatepage to adjust the dirty region
Fix afs_invalidatepage() to adjust the dirty region recorded in
page->private when truncating a page.  If the dirty region is entirely
removed, then the private data is cleared and the page dirty state is
cleared.

Without this, if the page is truncated and then expanded again by truncate,
zeros from the expanded, but no-longer dirty region may get written back to
the server if the page gets laundered due to a conflicting 3rd-party write.

It mustn't, however, shorten the dirty region of the page if that page is
still mmapped and has been marked dirty by afs_page_mkwrite(), so a flag is
stored in page->private to record this.

Fixes: 4343d00872 ("afs: Get rid of the afs_writeback record")
Signed-off-by: David Howells <dhowells@redhat.com>
2020-10-29 13:53:04 +00:00
David Howells
65dd2d6072 afs: Alter dirty range encoding in page->private
Currently, page->private on an afs page is used to store the range of
dirtied data within the page, where the range includes the lower bound, but
excludes the upper bound (e.g. 0-1 is a range covering a single byte).

This, however, requires a superfluous bit for the last-byte bound so that
on a 4KiB page, it can say 0-4096 to indicate the whole page, the idea
being that having both numbers the same would indicate an empty range.
This is unnecessary as the PG_private bit is clear if it's an empty range
(as is PG_dirty).

Alter the way the dirty range is encoded in page->private such that the
upper bound is reduced by 1 (e.g. 0-0 is then specified the same single
byte range mentioned above).

Applying this to both bounds frees up two bits, one of which can be used in
a future commit.

This allows the afs filesystem to be compiled on ppc32 with 64K pages;
without this, the following warnings are seen:

../fs/afs/internal.h: In function 'afs_page_dirty_to':
../fs/afs/internal.h:881:15: warning: right shift count >= width of type [-Wshift-count-overflow]
  881 |  return (priv >> __AFS_PAGE_PRIV_SHIFT) & __AFS_PAGE_PRIV_MASK;
      |               ^~
../fs/afs/internal.h: In function 'afs_page_dirty':
../fs/afs/internal.h:886:28: warning: left shift count >= width of type [-Wshift-count-overflow]
  886 |  return ((unsigned long)to << __AFS_PAGE_PRIV_SHIFT) | from;
      |                            ^~

Fixes: 4343d00872 ("afs: Get rid of the afs_writeback record")
Signed-off-by: David Howells <dhowells@redhat.com>
2020-10-29 13:53:04 +00:00
David Howells
185f0c7073 afs: Wrap page->private manipulations in inline functions
The afs filesystem uses page->private to store the dirty range within a
page such that in the event of a conflicting 3rd-party write to the server,
we write back just the bits that got changed locally.

However, there are a couple of problems with this:

 (1) I need a bit to note if the page might be mapped so that partial
     invalidation doesn't shrink the range.

 (2) There aren't necessarily sufficient bits to store the entire range of
     data altered (say it's a 32-bit system with 64KiB pages or transparent
     huge pages are in use).

So wrap the accesses in inline functions so that future commits can change
how this works.

Also move them out of the tracing header into the in-directory header.
There's not really any need for them to be in the tracing header.

Signed-off-by: David Howells <dhowells@redhat.com>
2020-10-29 13:53:04 +00:00
David Howells
f792e3ac82 afs: Fix where page->private is set during write
In afs, page->private is set to indicate the dirty region of a page.  This
is done in afs_write_begin(), but that can't take account of whether the
copy into the page actually worked.

Fix this by moving the change of page->private into afs_write_end().

Fixes: 4343d00872 ("afs: Get rid of the afs_writeback record")
Signed-off-by: David Howells <dhowells@redhat.com>
2020-10-29 13:53:04 +00:00
David Howells
21db2cdc66 afs: Fix page leak on afs_write_begin() failure
Fix the leak of the target page in afs_write_begin() when it fails.

Fixes: 15b4650e55 ("afs: convert to new aops")
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Nick Piggin <npiggin@gmail.com>
2020-10-29 13:53:04 +00:00
David Howells
fa04a40b16 afs: Fix to take ref on page when PG_private is set
Fix afs to take a ref on a page when it sets PG_private on it and to drop
the ref when removing the flag.

Note that in afs_write_begin(), a lot of the time, PG_private is already
set on a page to which we're going to add some data.  In such a case, we
leave the bit set and mustn't increment the page count.

As suggested by Matthew Wilcox, use attach/detach_page_private() where
possible.

Fixes: 31143d5d51 ("AFS: implement basic file write support")
Reported-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
2020-10-29 13:53:04 +00:00
David Howells
d383e346f9 afs: Fix afs_launder_page to not clear PG_writeback
Fix afs_launder_page() to not clear PG_writeback on the page it is
laundering as the flag isn't set in this case.

Fixes: 4343d00872 ("afs: Get rid of the afs_writeback record")
Signed-off-by: David Howells <dhowells@redhat.com>
2020-10-27 22:05:56 +00:00
Dan Carpenter
248c944e21 afs: Fix a use after free in afs_xattr_get_acl()
The "op" pointer is freed earlier when we call afs_put_operation().

Fixes: e49c7b2f6d ("afs: Build an abstraction around an "operation" concept")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Colin Ian King <colin.king@canonical.com>
2020-10-27 22:05:56 +00:00
David Howells
acc080d15d afs: Fix tracing deref-before-check
The patch dca54a7bbb: "afs: Add tracing for cell refcount and active user
count" from Oct 13, 2020, leads to the following Smatch complaint:

    fs/afs/cell.c:596 afs_unuse_cell()
    warn: variable dereferenced before check 'cell' (see line 592)

Fix this by moving the retrieval of the cell debug ID to after the check of
the validity of the cell pointer.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Fixes: dca54a7bbb ("afs: Add tracing for cell refcount and active user count")
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Dan Carpenter <dan.carpenter@oracle.com>
2020-10-27 22:05:56 +00:00
David Howells
06a17bbe1d afs: Fix copy_file_range()
The prevention of splice-write without explicit ops made the
copy_file_write() syscall to an afs file (as done by the generic/112
xfstest) fail with EINVAL.

Fix by using iter_file_splice_write() for afs.

Fixes: 36e2c7421f ("fs: don't allow splice read/write without explicit ops")
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2020-10-27 22:05:56 +00:00
Linus Torvalds
fad70111d5 afs fixes
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCAAdFiEEqG5UsNXhtOCrfGQP+7dXa6fLC2sFAl+JqvsACgkQ+7dXa6fL
 C2sQeRAAiW+rGQa46ybOv8qBLgVEiH6OzNUk62fesbhl5rKRgapS2r2SJbau29gv
 KqBld29lp4o84/THJ6hZ6Al1iwZnO2FW+h53Q47M5TH9AbwZhf/zooRSoGb5AmKJ
 /FR4+K/zTLk7VCSptTtXlKG81bOKQF+tmi6sLdxx70h2T+Ythm3zdVq8PCZZhhGG
 hw1IfuNDNbUDGus5WgZfIdVkdFCs5WW5cEhrPgqKR0mXYQklnkwgtov/+RAh/Ewf
 bZ1JFqap15KJ2AcKgw79NZ01MBJ4KyZckzKwgaTVlIEtCMQMBDhJpbKzdtP767rh
 xkxdzmDmXOop9RNQ8WrIIt6EjpB0We2qxQVGLsPHdEixmlv5n2BjL/wdWa3u/4QZ
 ymjv7B8jcFSpXQzVnrmeNYsgHo1oJ7G8q8Xh+CJm9BNBtNUiz1raQfxWpS5TeWT4
 dQsr/Z/PMCBCBOb6F08pjF8od67DUCx+x1nkCG4qFCeXiC4ouTNkfMZnxWH9mVKP
 v5Hca2E0ilR3PI5+tn8o/ZPul5NDTesBnAvAAEBQDT79Ff8kAgEJ3M3ipy38VoKV
 xFiNpNHwDPp15vzneJ7f7Ir27VauRlhCLEuSUtyYH4pD458K3UQAAQRFZB7bkzMX
 TQTbmEPUbtrs/mOEMKQN6ew8dwawRpMy01j0KnDl0KBFDtfTLU8=
 =0anM
 -----END PGP SIGNATURE-----

Merge tag 'afs-fixes-20201016' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

Pull afs updates from David Howells:
 "A collection of fixes to fix afs_cell struct refcounting, thereby
  fixing a slew of related syzbot bugs:

   - Fix the cell tree in the netns to use an rwsem rather than RCU.

     There seem to be some problems deriving from the use of RCU and a
     seqlock to walk the rbtree, but it's not entirely clear what since
     there are several different failures being seen.

     Changing things to use an rwsem instead makes it more robust. The
     extra performance derived from using RCU isn't necessary in this
     case since the only time we're looking up a cell is during mount or
     when cells are being manually added.

   - Fix the refcounting by splitting the usage counter into a memory
     refcount and an active users counter. The usage counter was doing
     double duty, keeping track of whether a cell is still in use and
     keeping track of when it needs to be destroyed - but this makes the
     clean up tricky. Separating these out simplifies the logic.

   - Fix purging a cell that has an alias. A cell alias pins the cell
     it's an alias of, but the alias is always later in the list. Trying
     to purge in a single pass causes rmmod to hang in such a case.

   - Fix cell removal. If a cell's manager is requeued whilst it's
     removing itself, the manager will run again and re-remove itself,
     causing problems in various places. Follow Hillf Danton's
     suggestion to insert a more terminal state that causes the manager
     to do nothing post-removal.

  In additional to the above, two other changes:

   - Add a tracepoint for the cell refcount and active users count. This
     helped with debugging the above and may be useful again in future.

   - Downgrade an assertion to a print when a still-active server is
     seen during purging. This was happening as a consequence of
     incomplete cell removal before the servers were cleaned up"

* tag 'afs-fixes-20201016' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
  afs: Don't assert on unpurgeable server records
  afs: Add tracing for cell refcount and active user count
  afs: Fix cell removal
  afs: Fix cell purging with aliases
  afs: Fix cell refcounting by splitting the usage counter
  afs: Fix rapid cell addition/removal by not using RCU on cells tree
2020-10-16 15:22:41 -07:00
David Howells
7530d3eb3d afs: Don't assert on unpurgeable server records
Don't give an assertion failure on unpurgeable afs_server records - which
kills the thread - but rather emit a trace line when we are purging a
record (which only happens during network namespace removal or rmmod) and
print a notice of the problem.

Signed-off-by: David Howells <dhowells@redhat.com>
2020-10-16 14:39:34 +01:00
David Howells
dca54a7bbb afs: Add tracing for cell refcount and active user count
Add a tracepoint to log the cell refcount and active user count and pass in
a reason code through various functions that manipulate these counters.

Additionally, a helper function, afs_see_cell(), is provided to log
interesting places that deal with a cell without actually doing any
accounting directly.

Signed-off-by: David Howells <dhowells@redhat.com>
2020-10-16 14:39:21 +01:00
David Howells
1d0e850a49 afs: Fix cell removal
Fix cell removal by inserting a more final state than AFS_CELL_FAILED that
indicates that the cell has been unpublished in case the manager is already
requeued and will go through again.  The new AFS_CELL_REMOVED state will
just immediately leave the manager function.

Going through a second time in the AFS_CELL_FAILED state will cause it to
try to remove the cell again, potentially leading to the proc list being
removed.

Fixes: 989782dcdc ("afs: Overhaul cell database management")
Reported-by: syzbot+b994ecf2b023f14832c1@syzkaller.appspotmail.com
Reported-by: syzbot+0e0db88e1eb44a91ae8d@syzkaller.appspotmail.com
Reported-by: syzbot+2d0585e5efcd43d113c2@syzkaller.appspotmail.com
Reported-by: syzbot+1ecc2f9d3387f1d79d42@syzkaller.appspotmail.com
Reported-by: syzbot+18d51774588492bf3f69@syzkaller.appspotmail.com
Reported-by: syzbot+a5e4946b04d6ca8fa5f3@syzkaller.appspotmail.com
Suggested-by: Hillf Danton <hdanton@sina.com>
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Hillf Danton <hdanton@sina.com>
2020-10-16 14:38:26 +01:00
David Howells
286377f6bd afs: Fix cell purging with aliases
When the afs module is removed, one of the things that has to be done is to
purge the cell database.  afs_cell_purge() cancels the management timer and
then starts the cell manager work item to do the purging.  This does a
single run through and then assumes that all cells are now purged - but
this is no longer the case.

With the introduction of alias detection, a later cell in the database can
now be holding an active count on an earlier cell (cell->alias_of).  The
purge scan passes by the earlier cell first, but this can't be got rid of
until it has discarded the alias.  Ordinarily, afs_unuse_cell() would
handle this by setting the management timer to trigger another pass - but
afs_set_cell_timer() doesn't do anything if the namespace is being removed
(net->live == false).  rmmod then hangs in the wait on cells_outstanding in
afs_cell_purge().

Fix this by making afs_set_cell_timer() directly queue the cell manager if
net->live is false.  This causes additional management passes.

Queueing the cell manager increments cells_outstanding to make sure the
wait won't complete until all cells are destroyed.

Fixes: 8a070a9648 ("afs: Detect cell aliases 1 - Cells with root volumes")
Signed-off-by: David Howells <dhowells@redhat.com>
2020-10-16 14:38:26 +01:00
David Howells
88c853c3f5 afs: Fix cell refcounting by splitting the usage counter
Management of the lifetime of afs_cell struct has some problems due to the
usage counter being used to determine whether objects of that type are in
use in addition to whether anyone might be interested in the structure.

This is made trickier by cell objects being cached for a period of time in
case they're quickly reused as they hold the result of a setup process that
may be slow (DNS lookups, AFS RPC ops).

Problems include the cached root volume from alias resolution pinning its
parent cell record, rmmod occasionally hanging and occasionally producing
assertion failures.

Fix this by splitting the count of active users from the struct reference
count.  Things then work as follows:

 (1) The cell cache keeps +1 on the cell's activity count and this has to
     be dropped before the cell can be removed.  afs_manage_cell() tries to
     exchange the 1 to a 0 with the cells_lock write-locked, and if
     successful, the record is removed from the net->cells.

 (2) One struct ref is 'owned' by the activity count.  That is put when the
     active count is reduced to 0 (final_destruction label).

 (3) A ref can be held on a cell whilst it is queued for management on a
     work queue without confusing the active count.  afs_queue_cell() is
     added to wrap this.

 (4) The queue's ref is dropped at the end of the management.  This is
     split out into a separate function, afs_manage_cell_work().

 (5) The root volume record is put after a cell is removed (at the
     final_destruction label) rather then in the RCU destruction routine.

 (6) Volumes hold struct refs, but aren't active users.

 (7) Both counts are displayed in /proc/net/afs/cells.

There are some management function changes:

 (*) afs_put_cell() now just decrements the refcount and triggers the RCU
     destruction if it becomes 0.  It no longer sets a timer to have the
     manager do this.

 (*) afs_use_cell() and afs_unuse_cell() are added to increase and decrease
     the active count.  afs_unuse_cell() sets the management timer.

 (*) afs_queue_cell() is added to queue a cell with approprate refs.

There are also some other fixes:

 (*) Don't let /proc/net/afs/cells access a cell's vllist if it's NULL.

 (*) Make sure that candidate cells in lookups are properly destroyed
     rather than being simply kfree'd.  This ensures the bits it points to
     are destroyed also.

 (*) afs_dec_cells_outstanding() is now called in cell destruction rather
     than at "final_destruction".  This ensures that cell->net is still
     valid to the end of the destructor.

 (*) As a consequence of the previous two changes, move the increment of
     net->cells_outstanding that was at the point of insertion into the
     tree to the allocation routine to correctly balance things.

Fixes: 989782dcdc ("afs: Overhaul cell database management")
Signed-off-by: David Howells <dhowells@redhat.com>
2020-10-16 14:38:22 +01:00
David Howells
92e3cc91d8 afs: Fix rapid cell addition/removal by not using RCU on cells tree
There are a number of problems that are being seen by the rapidly mounting
and unmounting an afs dynamic root with an explicit cell and volume
specified (which should probably be rejected, but that's a separate issue):

What the tests are doing is to look up/create a cell record for the name
given and then tear it down again without actually using it to try to talk
to a server.  This is repeated endlessly, very fast, and the new cell
collides with the old one if it's not quick enough to reuse it.

It appears (as suggested by Hillf Danton) that the search through the RB
tree under a read_seqbegin_or_lock() under RCU conditions isn't safe and
that it's not blocking the write_seqlock(), despite taking two passes at
it.  He suggested that the code should take a ref on the cell it's
attempting to look at - but this shouldn't be necessary until we've
compared the cell names.  It's possible that I'm missing a barrier
somewhere.

However, using an RCU search for this is overkill, really - we only need to
access the cell name in a few places, and they're places where we're may
end up sleeping anyway.

Fix this by switching to an R/W semaphore instead.

Additionally, draw the down_read() call inside the function (renamed to
afs_find_cell()) since all the callers were taking the RCU read lock (or
should've been[*]).

[*] afs_probe_cell_name() should have been, but that doesn't appear to be
involved in the bug reports.

The symptoms of this look like:

	general protection fault, probably for non-canonical address 0xf27d208691691fdb: 0000 [#1] PREEMPT SMP KASAN
	KASAN: maybe wild-memory-access in range [0x93e924348b48fed8-0x93e924348b48fedf]
	...
	RIP: 0010:strncasecmp lib/string.c:52 [inline]
	RIP: 0010:strncasecmp+0x5f/0x240 lib/string.c:43
	 afs_lookup_cell_rcu+0x313/0x720 fs/afs/cell.c:88
	 afs_lookup_cell+0x2ee/0x1440 fs/afs/cell.c:249
	 afs_parse_source fs/afs/super.c:290 [inline]
	...

Fixes: 989782dcdc ("afs: Overhaul cell database management")
Reported-by: syzbot+459a5dce0b4cb70fd076@syzkaller.appspotmail.com
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Hillf Danton <hdanton@sina.com>
cc: syzkaller-bugs@googlegroups.com
2020-10-16 14:04:59 +01:00
Linus Torvalds
3ad11d7ac8 block-5.10-2020-10-12
-----BEGIN PGP SIGNATURE-----
 
 iQJEBAABCAAuFiEEwPw5LcreJtl1+l5K99NY+ylx4KYFAl+EWUgQHGF4Ym9lQGtl
 cm5lbC5kawAKCRD301j7KXHgpnoxEADCVSNBRkpV0OVkOEC3wf8EGhXhk01Jnjtl
 u5Mg2V55hcgJ0thQxBV/V28XyqmsEBrmAVi0Yf8Vr9Qbq4Ze08Wae4ChS4rEOyh1
 jTcGYWx5aJB3ChLvV/HI0nWQ3bkj03mMrL3SW8rhhf5DTyKHsVeTenpx42Qu/FKf
 fRzi09FSr3Pjd0B+EX6gunwJnlyXQC5Fa4AA0GhnXJzAznANXxHkkcXu8a6Yw75x
 e28CfhIBliORsK8sRHLoUnPpeTe1vtxCBhBMsE+gJAj9ZUOWMzvNFIPP4FvfawDy
 6cCQo2m1azJ/IdZZCDjFUWyjh+wxdKMp+NNryEcoV+VlqIoc3n98rFwrSL+GIq5Z
 WVwEwq+AcwoMCsD29Lu1ytL2PQ/RVqcJP5UheMrbL4vzefNfJFumQVZLIcX0k943
 8dFL2QHL+H/hM9Dx5y5rjeiWkAlq75v4xPKVjh/DHb4nehddCqn/+DD5HDhNANHf
 c1kmmEuYhvLpIaC4DHjE6DwLh8TPKahJjwsGuBOTr7D93NUQD+OOWsIhX6mNISIl
 FFhP8cd0/ZZVV//9j+q+5B4BaJsT+ZtwmrelKFnPdwPSnh+3iu8zPRRWO+8P8fRC
 YvddxuJAmE6BLmsAYrdz6Xb/wqfyV44cEiyivF0oBQfnhbtnXwDnkDWSfJD1bvCm
 ZwfpDh2+Tg==
 =LzyE
 -----END PGP SIGNATURE-----

Merge tag 'block-5.10-2020-10-12' of git://git.kernel.dk/linux-block

Pull block updates from Jens Axboe:

 - Series of merge handling cleanups (Baolin, Christoph)

 - Series of blk-throttle fixes and cleanups (Baolin)

 - Series cleaning up BDI, seperating the block device from the
   backing_dev_info (Christoph)

 - Removal of bdget() as a generic API (Christoph)

 - Removal of blkdev_get() as a generic API (Christoph)

 - Cleanup of is-partition checks (Christoph)

 - Series reworking disk revalidation (Christoph)

 - Series cleaning up bio flags (Christoph)

 - bio crypt fixes (Eric)

 - IO stats inflight tweak (Gabriel)

 - blk-mq tags fixes (Hannes)

 - Buffer invalidation fixes (Jan)

 - Allow soft limits for zone append (Johannes)

 - Shared tag set improvements (John, Kashyap)

 - Allow IOPRIO_CLASS_RT for CAP_SYS_NICE (Khazhismel)

 - DM no-wait support (Mike, Konstantin)

 - Request allocation improvements (Ming)

 - Allow md/dm/bcache to use IO stat helpers (Song)

 - Series improving blk-iocost (Tejun)

 - Various cleanups (Geert, Damien, Danny, Julia, Tetsuo, Tian, Wang,
   Xianting, Yang, Yufen, yangerkun)

* tag 'block-5.10-2020-10-12' of git://git.kernel.dk/linux-block: (191 commits)
  block: fix uapi blkzoned.h comments
  blk-mq: move cancel of hctx->run_work to the front of blk_exit_queue
  blk-mq: get rid of the dead flush handle code path
  block: get rid of unnecessary local variable
  block: fix comment and add lockdep assert
  blk-mq: use helper function to test hw stopped
  block: use helper function to test queue register
  block: remove redundant mq check
  block: invoke blk_mq_exit_sched no matter whether have .exit_sched
  percpu_ref: don't refer to ref->data if it isn't allocated
  block: ratelimit handle_bad_sector() message
  blk-throttle: Re-use the throtl_set_slice_end()
  blk-throttle: Open code __throtl_de/enqueue_tg()
  blk-throttle: Move service tree validation out of the throtl_rb_first()
  blk-throttle: Move the list operation after list validation
  blk-throttle: Fix IO hang for a corner case
  blk-throttle: Avoid tracking latency if low limit is invalid
  blk-throttle: Avoid getting the current time if tg->last_finish_time is 0
  blk-throttle: Remove a meaningless parameter for throtl_downgrade_state()
  block: Remove redundant 'return' statement
  ...
2020-10-13 12:12:44 -07:00
David Howells
ec0fa0b659 afs: Fix deadlock between writeback and truncate
The afs filesystem has a lock[*] that it uses to serialise I/O operations
going to the server (vnode->io_lock), as the server will only perform one
modification operation at a time on any given file or directory.  This
prevents the the filesystem from filling up all the call slots to a server
with calls that aren't going to be executed in parallel anyway, thereby
allowing operations on other files to obtain slots.

  [*] Note that is probably redundant for directories at least since
      i_rwsem is used to serialise directory modifications and
      lookup/reading vs modification.  The server does allow parallel
      non-modification ops, however.

When a file truncation op completes, we truncate the in-memory copy of the
file to match - but we do it whilst still holding the io_lock, the idea
being to prevent races with other operations.

However, if writeback starts in a worker thread simultaneously with
truncation (whilst notify_change() is called with i_rwsem locked, writeback
pays it no heed), it may manage to set PG_writeback bits on the pages that
will get truncated before afs_setattr_success() manages to call
truncate_pagecache().  Truncate will then wait for those pages - whilst
still inside io_lock:

    # cat /proc/8837/stack
    [<0>] wait_on_page_bit_common+0x184/0x1e7
    [<0>] truncate_inode_pages_range+0x37f/0x3eb
    [<0>] truncate_pagecache+0x3c/0x53
    [<0>] afs_setattr_success+0x4d/0x6e
    [<0>] afs_wait_for_operation+0xd8/0x169
    [<0>] afs_do_sync_operation+0x16/0x1f
    [<0>] afs_setattr+0x1fb/0x25d
    [<0>] notify_change+0x2cf/0x3c4
    [<0>] do_truncate+0x7f/0xb2
    [<0>] do_sys_ftruncate+0xd1/0x104
    [<0>] do_syscall_64+0x2d/0x3a
    [<0>] entry_SYSCALL_64_after_hwframe+0x44/0xa9

The writeback operation, however, stalls indefinitely because it needs to
get the io_lock to proceed:

    # cat /proc/5940/stack
    [<0>] afs_get_io_locks+0x58/0x1ae
    [<0>] afs_begin_vnode_operation+0xc7/0xd1
    [<0>] afs_store_data+0x1b2/0x2a3
    [<0>] afs_write_back_from_locked_page+0x418/0x57c
    [<0>] afs_writepages_region+0x196/0x224
    [<0>] afs_writepages+0x74/0x156
    [<0>] do_writepages+0x2d/0x56
    [<0>] __writeback_single_inode+0x84/0x207
    [<0>] writeback_sb_inodes+0x238/0x3cf
    [<0>] __writeback_inodes_wb+0x68/0x9f
    [<0>] wb_writeback+0x145/0x26c
    [<0>] wb_do_writeback+0x16a/0x194
    [<0>] wb_workfn+0x74/0x177
    [<0>] process_one_work+0x174/0x264
    [<0>] worker_thread+0x117/0x1b9
    [<0>] kthread+0xec/0xf1
    [<0>] ret_from_fork+0x1f/0x30

and thus deadlock has occurred.

Note that whilst afs_setattr() calls filemap_write_and_wait(), the fact
that the caller is holding i_rwsem doesn't preclude more pages being
dirtied through an mmap'd region.

Fix this by:

 (1) Use the vnode validate_lock to mediate access between afs_setattr()
     and afs_writepages():

     (a) Exclusively lock validate_lock in afs_setattr() around the whole
     	 RPC operation.

     (b) If WB_SYNC_ALL isn't set on entry to afs_writepages(), trying to
     	 shared-lock validate_lock and returning immediately if we couldn't
     	 get it.

     (c) If WB_SYNC_ALL is set, wait for the lock.

     The validate_lock is also used to validate a file and to zap its cache
     if the file was altered by a third party, so it's probably a good fit
     for this.

 (2) Move the truncation outside of the io_lock in setattr, using the same
     hook as is used for local directory editing.

     This requires the old i_size to be retained in the operation record as
     we commit the revised status to the inode members inside the io_lock
     still, but we still need to know if we reduced the file size.

Fixes: d2ddc776a4 ("afs: Overhaul volume and server record caching and fileserver rotation")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-08 10:50:55 -07:00
Christoph Hellwig
55b2598e84 bdi: initialize ->ra_pages and ->io_pages in bdi_init
Set up a readahead size by default, as very few users have a good
reason to change it.  This means code, ecryptfs, and orangefs now
set up the values while they were previously missing it, while ubifs,
mtd and vboxsf manually set it to 0 to avoid readahead.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: David Sterba <dsterba@suse.com> [btrfs]
Acked-by: Richard Weinberger <richard@nod.at> [ubifs, mtd]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-09-24 13:43:39 -06:00
Linus Torvalds
3e8d3bdc2a Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from David Miller:

 1) Use netif_rx_ni() when necessary in batman-adv stack, from Jussi
    Kivilinna.

 2) Fix loss of RTT samples in rxrpc, from David Howells.

 3) Memory leak in hns_nic_dev_probe(), from Dignhao Liu.

 4) ravb module cannot be unloaded, fix from Yuusuke Ashizuka.

 5) We disable BH for too lokng in sctp_get_port_local(), add a
    cond_resched() here as well, from Xin Long.

 6) Fix memory leak in st95hf_in_send_cmd, from Dinghao Liu.

 7) Out of bound access in bpf_raw_tp_link_fill_link_info(), from
    Yonghong Song.

 8) Missing of_node_put() in mt7530 DSA driver, from Sumera
    Priyadarsini.

 9) Fix crash in bnxt_fw_reset_task(), from Michael Chan.

10) Fix geneve tunnel checksumming bug in hns3, from Yi Li.

11) Memory leak in rxkad_verify_response, from Dinghao Liu.

12) In tipc, don't use smp_processor_id() in preemptible context. From
    Tuong Lien.

13) Fix signedness issue in mlx4 memory allocation, from Shung-Hsi Yu.

14) Missing clk_disable_prepare() in gemini driver, from Dan Carpenter.

15) Fix ABI mismatch between driver and firmware in nfp, from Louis
    Peens.

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (110 commits)
  net/smc: fix sock refcounting in case of termination
  net/smc: reset sndbuf_desc if freed
  net/smc: set rx_off for SMCR explicitly
  net/smc: fix toleration of fake add_link messages
  tg3: Fix soft lockup when tg3_reset_task() fails.
  doc: net: dsa: Fix typo in config code sample
  net: dp83867: Fix WoL SecureOn password
  nfp: flower: fix ABI mismatch between driver and firmware
  tipc: fix shutdown() of connectionless socket
  ipv6: Fix sysctl max for fib_multipath_hash_policy
  drivers/net/wan/hdlc: Change the default of hard_header_len to 0
  net: gemini: Fix another missing clk_disable_unprepare() in probe
  net: bcmgenet: fix mask check in bcmgenet_validate_flow()
  amd-xgbe: Add support for new port mode
  net: usb: dm9601: Add USB ID of Keenetic Plus DSL
  vhost: fix typo in error message
  net: ethernet: mlx4: Fix memory allocation in mlx4_buddy_init()
  pktgen: fix error message with wrong function name
  net: ethernet: ti: am65-cpsw: fix rmii 100Mbit link mode
  cxgb4: fix thermal zone device registration
  ...
2020-09-03 18:50:48 -07:00
David S. Miller
8d73a73a7f RxRPC fixes
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCAAdFiEEqG5UsNXhtOCrfGQP+7dXa6fLC2sFAl9HwPIACgkQ+7dXa6fL
 C2vHdw//S5s+nPNuJUpz3aeYDC1Yl1YP+r2+XBfcCNem504GKfsvTBbLo7FYP6Oc
 TCLJouPxoNSWAtlrJ86YJu8EcFdYNI4w6mCHncIrLXiiIZhsAeUMAw1GiASL5VUr
 QhLjJJU4zUBg3/RWLRC1pUXBXAa3sYx5r1p8j3KdBAkAmAzXdFWSRFeffVeXIk46
 FZ52YoQkplJYqDL+1oQCjJLetVJGGvc68AIOjJOLh6CAjrZbx1aiY79XA+flsoE9
 B+KVjhEn0f9dVybgtF4rEqS88y1FJtSQgul6FOsys+Rx2I0G7ei8PB5TQ2wNCQhy
 37gGfg1AV6apcqXKcHJdovVnApoQzzdCJESCgbMvsczqM88dP7pLWrPz4wpxs655
 3t6qUyXI6yMOJhUWPOoFi30+4NM+MmsqrbYLZt2f/aXRhKnyaeaLd+VAIlkgz3Lj
 sZuuHQsTH0xiR2uCsINWEc7d7UV6WjeVUJ77LzYiiRzEC2pX80tGu5EKHN8W9oBk
 xRAuExXEGtyOR0p3/S3StkT490Tt4bIxUwnKYAaQZEydMCnTlWVbtIXwzmlCbCSB
 p+P/7twR7LiQlHCTJU94jH3Jfpm3jpFpgjQZoZcx6ZLvtSH4+QP11nMY9+sRxEz1
 hpB12AY7Wp2N7P+GhBPuXUCQpzW751aNZz4X9Etu6kRgwjuyaJM=
 =FWHJ
 -----END PGP SIGNATURE-----

Merge tag 'rxrpc-fixes-20200820' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

David Howells says:

====================
rxrpc, afs: Fix probing issues

Here are some fixes for rxrpc and afs to fix issues in the RTT measuring in
rxrpc and thence the Volume Location server probing in afs:

 (1) Move the serial number of a received ACK into a local variable to
     simplify the next patch.

 (2) Fix the loss of RTT samples due to extra interposed ACKs causing
     baseline information to be discarded too early.  This is a particular
     problem for afs when it sends a single very short call to probe a
     server it hasn't talked to recently.

 (3) Fix rxrpc_kernel_get_srtt() to indicate whether it actually has seen
     any valid samples or not.

 (4) Remove a field that's set/woken, but never read/waited on.

 (5) Expose the RTT and other probe information through procfs to make
     debugging of this stuff easier.

 (6) Fix VL rotation in afs to only use summary information from VL probing
     and not the probe running state (which gets clobbered when next a
     probe is issued).

 (7) Fix VL rotation to actually return the error aggregated from the probe
     errors.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-08-27 12:55:46 -07:00
Dan Carpenter
210e799ed2 afs: Remove erroneous fallthough annotation
The fall through annotation comes after a return statement so it's not
reachable.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-08-27 14:33:01 -05:00
Gustavo A. R. Silva
df561f6688 treewide: Use fallthrough pseudo-keyword
Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-08-23 17:36:59 -05:00
David Howells
5e0b17b026 afs: Fix NULL deref in afs_dynroot_depopulate()
If an error occurs during the construction of an afs superblock, it's
possible that an error occurs after a superblock is created, but before
we've created the root dentry.  If the superblock has a dynamic root
(ie.  what's normally mounted on /afs), the afs_kill_super() will call
afs_dynroot_depopulate() to unpin any created dentries - but this will
oops if the root hasn't been created yet.

Fix this by skipping that bit of code if there is no root dentry.

This leads to an oops looking like:

	general protection fault, ...
	KASAN: null-ptr-deref in range [0x0000000000000068-0x000000000000006f]
	...
	RIP: 0010:afs_dynroot_depopulate+0x25f/0x529 fs/afs/dynroot.c:385
	...
	Call Trace:
	 afs_kill_super+0x13b/0x180 fs/afs/super.c:535
	 deactivate_locked_super+0x94/0x160 fs/super.c:335
	 afs_get_tree+0x1124/0x1460 fs/afs/super.c:598
	 vfs_get_tree+0x89/0x2f0 fs/super.c:1547
	 do_new_mount fs/namespace.c:2875 [inline]
	 path_mount+0x1387/0x2070 fs/namespace.c:3192
	 do_mount fs/namespace.c:3205 [inline]
	 __do_sys_mount fs/namespace.c:3413 [inline]
	 __se_sys_mount fs/namespace.c:3390 [inline]
	 __x64_sys_mount+0x27f/0x300 fs/namespace.c:3390
	 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
	 entry_SYSCALL_64_after_hwframe+0x44/0xa9

which is oopsing on this line:

	inode_lock(root->d_inode);

presumably because sb->s_root was NULL.

Fixes: 0da0b7fd73 ("afs: Display manually added cells in dynamic root mount")
Reported-by: syzbot+c1eff8205244ae7e11a6@syzkaller.appspotmail.com
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-21 10:56:40 -07:00
David Howells
ba8e42077b afs: Fix key ref leak in afs_put_operation()
The afs_put_operation() function needs to put the reference to the key
that's authenticating the operation.

Fixes: e49c7b2f6d ("afs: Build an abstraction around an "operation" concept")
Reported-by: Dave Botsch <botsch@cnf.cornell.edu>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-20 10:41:45 -07:00
David Howells
e4686c79b1 afs: Fix error handling in VL server rotation
The error handling in the VL server rotation in the case of there being no
contactable servers is not correct.  In such a case, the records of all the
servers in the list are scanned and the errors and abort codes are mapped
and prioritised and one error is chosen.  This is then forgotten and the
default error is used (EDESTADDRREQ).

Fix this by using the calculated error.

Also we need to note whether a server responded on one of its endpoints so
that we can priorise an error from an abort message over local and network
errors.

Fixes: 4584ae96ae ("afs: Fix missing net error handling")
Signed-off-by: David Howells <dhowells@redhat.com>
2020-08-20 18:21:28 +01:00
David Howells
b95b30940e afs: Don't use VL probe running state to make decisions outside probe code
Don't use the running state for VL server probes to make decisions about
which server to use as the state is cleared at the start of a probe and
intermediate values might also be misleading.

Instead, add a separate 'latest known' rtt in the afs_vlserver struct and a
flag to indicate if the server is known to be responding and update these
as and when we know what to change them to.

Fixes: 3bf0fb6f33 ("afs: Probe multiple fileservers simultaneously")
Signed-off-by: David Howells <dhowells@redhat.com>
2020-08-20 18:21:28 +01:00
David Howells
fb72cd3d48 afs: Expose information from afs_vlserver through /proc for debugging
Convert various bitfields in afs_vlserver::probe to a mask and then expose
this and some other bits of information through /proc/net/afs/<cell>/vlservers
to make it easier to debug VL server communication issues.

Signed-off-by: David Howells <dhowells@redhat.com>
2020-08-20 18:21:28 +01:00
David Howells
4f4c2c05eb afs: Remove afs_vlserver->probe.have_result
Remove afs_vlserver->probe.have_result as it's neither read nor waited
upon.

Fixes: 3bf0fb6f33 ("afs: Probe multiple fileservers simultaneously")
Signed-off-by: David Howells <dhowells@redhat.com>
2020-08-20 18:21:28 +01:00
David Howells
1d4adfaf65 rxrpc: Make rxrpc_kernel_get_srtt() indicate validity
Fix rxrpc_kernel_get_srtt() to indicate the validity of the returned
smoothed RTT.  If we haven't had any valid samples yet, the SRTT isn't
useful.

Fixes: c410bf0193 ("rxrpc: Fix the excessive initial retransmission timeout")
Signed-off-by: David Howells <dhowells@redhat.com>
2020-08-20 18:21:28 +01:00
Linus Torvalds
99ea1521a0 Remove uninitialized_var() macro for v5.9-rc1
- Clean up non-trivial uses of uninitialized_var()
 - Update documentation and checkpatch for uninitialized_var() removal
 - Treewide removal of uninitialized_var()
 -----BEGIN PGP SIGNATURE-----
 
 iQJKBAABCgA0FiEEpcP2jyKd1g9yPm4TiXL039xtwCYFAl8oYLQWHGtlZXNjb29r
 QGNocm9taXVtLm9yZwAKCRCJcvTf3G3AJsfjEACvf0D3WL3H7sLHtZ2HeMwOgAzq
 il08t6vUscINQwiIIK3Be43ok3uQ1Q+bj8sr2gSYTwunV2IYHFferzgzhyMMno3o
 XBIGd1E+v1E4DGBOiRXJvacBivKrfvrdZ7AWiGlVBKfg2E0fL1aQbe9AYJ6eJSbp
 UGqkBkE207dugS5SQcwrlk1tWKUL089lhDAPd7iy/5RK76OsLRCJFzIerLHF2ZK2
 BwvA+NWXVQI6pNZ0aRtEtbbxwEU4X+2J/uaXH5kJDszMwRrgBT2qoedVu5LXFPi8
 +B84IzM2lii1HAFbrFlRyL/EMueVFzieN40EOB6O8wt60Y4iCy5wOUzAdZwFuSTI
 h0xT3JI8BWtpB3W+ryas9cl9GoOHHtPA8dShuV+Y+Q2bWe1Fs6kTl2Z4m4zKq56z
 63wQCdveFOkqiCLZb8s6FhnS11wKtAX4czvXRXaUPgdVQS1Ibyba851CRHIEY+9I
 AbtogoPN8FXzLsJn7pIxHR4ADz+eZ0dQ18f2hhQpP6/co65bYizNP5H3h+t9hGHG
 k3r2k8T+jpFPaddpZMvRvIVD8O2HvJZQTyY6Vvneuv6pnQWtr2DqPFn2YooRnzoa
 dbBMtpon+vYz6OWokC5QNWLqHWqvY9TmMfcVFUXE4AFse8vh4wJ8jJCNOFVp8On+
 drhmmImUr1YylrtVOw==
 =xHmk
 -----END PGP SIGNATURE-----

Merge tag 'uninit-macro-v5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

Pull uninitialized_var() macro removal from Kees Cook:
 "This is long overdue, and has hidden too many bugs over the years. The
  series has several "by hand" fixes, and then a trivial treewide
  replacement.

   - Clean up non-trivial uses of uninitialized_var()

   - Update documentation and checkpatch for uninitialized_var() removal

   - Treewide removal of uninitialized_var()"

* tag 'uninit-macro-v5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  compiler: Remove uninitialized_var() macro
  treewide: Remove uninitialized_var() usage
  checkpatch: Remove awareness of uninitialized_var() macro
  mm/debug_vm_pgtable: Remove uninitialized_var() usage
  f2fs: Eliminate usage of uninitialized_var() macro
  media: sur40: Remove uninitialized_var() usage
  KVM: PPC: Book3S PR: Remove uninitialized_var() usage
  clk: spear: Remove uninitialized_var() usage
  clk: st: Remove uninitialized_var() usage
  spi: davinci: Remove uninitialized_var() usage
  ide: Remove uninitialized_var() usage
  rtlwifi: rtl8192cu: Remove uninitialized_var() usage
  b43: Remove uninitialized_var() usage
  drbd: Remove uninitialized_var() usage
  x86/mm/numa: Remove uninitialized_var() usage
  docs: deprecated.rst: Add uninitialized_var()
2020-08-04 13:49:43 -07:00
Kees Cook
3f649ab728 treewide: Remove uninitialized_var() usage
Using uninitialized_var() is dangerous as it papers over real bugs[1]
(or can in the future), and suppresses unrelated compiler warnings
(e.g. "unused variable"). If the compiler thinks it is uninitialized,
either simply initialize the variable or make compiler changes.

In preparation for removing[2] the[3] macro[4], remove all remaining
needless uses with the following script:

git grep '\buninitialized_var\b' | cut -d: -f1 | sort -u | \
	xargs perl -pi -e \
		's/\buninitialized_var\(([^\)]+)\)/\1/g;
		 s:\s*/\* (GCC be quiet|to make compiler happy) \*/$::g;'

drivers/video/fbdev/riva/riva_hw.c was manually tweaked to avoid
pathological white-space.

No outstanding warnings were found building allmodconfig with GCC 9.3.0
for x86_64, i386, arm64, arm, powerpc, powerpc64le, s390x, mips, sparc64,
alpha, and m68k.

[1] https://lore.kernel.org/lkml/20200603174714.192027-1-glider@google.com/
[2] https://lore.kernel.org/lkml/CA+55aFw+Vbj0i=1TGqCR5vQkCzWJ0QxK6CernOU6eedsudAixw@mail.gmail.com/
[3] https://lore.kernel.org/lkml/CA+55aFwgbgqhbp1fkxvRKEpzyR5J8n1vKT1VZdz9knmPuXhOeg@mail.gmail.com/
[4] https://lore.kernel.org/lkml/CA+55aFz2500WfbKXAx8s67wrm9=yVJu65TpLgN_ybYNv0VEOKA@mail.gmail.com/

Reviewed-by: Leon Romanovsky <leonro@mellanox.com> # drivers/infiniband and mlx4/mlx5
Acked-by: Jason Gunthorpe <jgg@mellanox.com> # IB
Acked-by: Kalle Valo <kvalo@codeaurora.org> # wireless drivers
Reviewed-by: Chao Yu <yuchao0@huawei.com> # erofs
Signed-off-by: Kees Cook <keescook@chromium.org>
2020-07-16 12:35:15 -07:00
David Howells
811f04bac1 afs: Fix interruption of operations
The afs filesystem driver allows unstarted operations to be cancelled by
signal, but most of these can easily be restarted (mkdir for example).  The
primary culprits for reproducing this are those applications that use
SIGALRM to display a progress counter.

File lock-extension operation is marked uninterruptible as we have a
limited time in which to do it, and the release op is marked
uninterruptible also as if we fail to unlock a file, we'll have to wait 20
mins before anyone can lock it again.

The store operation logs a warning if it gets interruption, e.g.:

	kAFS: Unexpected error from FS.StoreData -4

because it's run from the background - but it can also be run from
fdatasync()-type things.  However, store options aren't marked
interruptible at the moment.

Fix this in the following ways:

 (1) Mark store operations as uninterruptible.  It might make sense to
     relax this for certain situations, but I'm not sure how to make sure
     that background store ops aren't affected by signals to foreground
     processes that happen to trigger them.

 (2) In afs_get_io_locks(), where we're getting the serialisation lock for
     talking to the fileserver, return ERESTARTSYS rather than EINTR
     because a lot of the operations (e.g. mkdir) are restartable if we
     haven't yet started sending the op to the server.

Fixes: e49c7b2f6d ("afs: Build an abstraction around an "operation" concept")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-07-15 15:49:04 -07:00
David Howells
719fdd3292 afs: Fix storage of cell names
The cell name stored in the afs_cell struct is a 64-char + NUL buffer -
when it needs to be able to handle up to AFS_MAXCELLNAME (256 chars) + NUL.

Fix this by changing the array to a pointer and allocating the string.

Found using Coverity.

Fixes: 989782dcdc ("afs: Overhaul cell database management")
Reported-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-27 22:04:24 -07:00
David Howells
5481fc6eb8 afs: Fix hang on rmmod due to outstanding timer
The fileserver probe timer, net->fs_probe_timer, isn't cancelled when
the kafs module is being removed and so the count it holds on
net->servers_outstanding doesn't get dropped..

This causes rmmod to wait forever.  The hung process shows a stack like:

	afs_purge_servers+0x1b5/0x23c [kafs]
	afs_net_exit+0x44/0x6e [kafs]
	ops_exit_list+0x72/0x93
	unregister_pernet_operations+0x14c/0x1ba
	unregister_pernet_subsys+0x1d/0x2a
	afs_exit+0x29/0x6f [kafs]
	__do_sys_delete_module.isra.0+0x1a2/0x24b
	do_syscall_64+0x51/0x95
	entry_SYSCALL_64_after_hwframe+0x44/0xa9

Fix this by:

 (1) Attempting to cancel the probe timer and, if successful, drop the
     count that the timer was holding.

 (2) Make the timer function just drop the count and not schedule the
     prober if the afs portion of net namespace is being destroyed.

Also, whilst we're at it, make the following changes:

 (3) Initialise net->servers_outstanding to 1 and decrement it before
     waiting on it so that it doesn't generate wake up events by being
     decremented to 0 until we're cleaning up.

 (4) Switch the atomic_dec() on ->servers_outstanding for ->fs_timer in
     afs_purge_servers() to use the helper function for that.

Fixes: f6cbb368bc ("afs: Actively poll fileservers to maintain NAT or firewall openings")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-20 12:01:58 -07:00
David Howells
f8ea5c7bce afs: Fix afs_do_lookup() to call correct fetch-status op variant
Fix afs_do_lookup()'s fallback case for when FS.InlineBulkStatus isn't
supported by the server.

In the fallback, it calls FS.FetchStatus for the specific vnode it's
meant to be looking up.  Commit b6489a49f7 broke this by renaming one
of the two identically-named afs_fetch_status_operation descriptors to
something else so that one of them could be made non-static.  The site
that used the renamed one, however, wasn't renamed and didn't produce
any warning because the other was declared in a header.

Fix this by making afs_do_lookup() use the renamed variant.

Note that there are two variants of the success method because one is
called from ->lookup() where we may or may not have an inode, but can't
call iget until after we've talked to the server - whereas the other is
called from within iget where we have an inode, but it may or may not be
initialised.

The latter variant expects there to be an inode, but because it's being
called from there former case, there might not be - resulting in an oops
like the following:

  BUG: kernel NULL pointer dereference, address: 00000000000000b0
  ...
  RIP: 0010:afs_fetch_status_success+0x27/0x7e
  ...
  Call Trace:
    afs_wait_for_operation+0xda/0x234
    afs_do_lookup+0x2fe/0x3c1
    afs_lookup+0x3c5/0x4bd
    __lookup_slow+0xcd/0x10f
    walk_component+0xa2/0x10c
    path_lookupat.isra.0+0x80/0x110
    filename_lookup+0x81/0x104
    vfs_statx+0x76/0x109
    __do_sys_newlstat+0x39/0x6b
    do_syscall_64+0x4c/0x78
    entry_SYSCALL_64_after_hwframe+0x44/0xa9

Fixes: b6489a49f7 ("afs: Fix silly rename")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-20 12:01:58 -07:00
David Howells
b6489a49f7 afs: Fix silly rename
Fix AFS's silly rename by the following means:

 (1) Set the destination directory in afs_do_silly_rename() so as to avoid
     misbehaviour and indicate that the directory data version will
     increment by 1 so as to avoid warnings about unexpected changes in the
     DV.  Also indicate that the ctime should be updated to avoid xfstest
     grumbling.

 (2) Note when the server indicates that a directory changed more than we
     expected (AFS_OPERATION_DIR_CONFLICT), indicating a conflict with a
     third party change, checking on successful completion of unlink and
     rename.

     The problem is that the FS.RemoveFile RPC op doesn't report the status
     of the unlinked file, though YFS.RemoveFile2 does.  This can be
     mitigated by the assumption that if the directory DV cranked by
     exactly 1, we can be sure we removed one link from the file; further,
     ordinarily in AFS, files cannot be hardlinked across directories, so
     if we reduce nlink to 0, the file is deleted.

     However, if the directory DV jumps by more than 1, we cannot know if a
     third party intervened by adding or removing a link on the file we
     just removed a link from.

     The same also goes for any vnode that is at the destination of the
     FS.Rename RPC op.

 (3) Make afs_vnode_commit_status() apply the nlink drop inside the cb_lock
     section along with the other attribute updates if ->op_unlinked is set
     on the descriptor for the appropriate vnode.

 (4) Issue a follow up status fetch to the unlinked file in the event of a
     third party conflict that makes it impossible for us to know if we
     actually deleted the file or not.

 (5) Provide a flag, AFS_VNODE_SILLY_DELETED, to make afs_getattr() lie to
     the user about the nlink of a silly deleted file so that it appears as
     0, not 1.

Found with the generic/035 and generic/084 xfstests.

Fixes: e49c7b2f6d ("afs: Build an abstraction around an "operation" concept")
Reported-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2020-06-16 22:00:28 +01:00
David Howells
7c295eec1e afs: afs_vnode_commit_status() doesn't need to check the RPC error
afs_vnode_commit_status() is only ever called if op->error is 0, so remove
the op->error checks from the function.

Fixes: e49c7b2f6d ("afs: Build an abstraction around an "operation" concept")
Signed-off-by: David Howells <dhowells@redhat.com>
2020-06-16 16:26:57 +01:00
David Howells
728279a5a1 afs: Fix use of afs_check_for_remote_deletion()
afs_check_for_remote_deletion() checks to see if error ENOENT is returned
by the server in response to an operation and, if so, marks the primary
vnode as having been deleted as the FID is no longer valid.

However, it's being called from the operation success functions, where no
abort has happened - and if an inline abort is recorded, it's handled by
afs_vnode_commit_status().

Fix this by actually calling the operation aborted method if provided and
having that point to afs_check_for_remote_deletion().

Fixes: e49c7b2f6d ("afs: Build an abstraction around an "operation" concept")
Signed-off-by: David Howells <dhowells@redhat.com>
2020-06-16 16:26:57 +01:00
David Howells
44767c3531 afs: Remove afs_operation::abort_code
Remove afs_operation::abort_code as it's read but never set.  Use
ac.abort_code instead.

Signed-off-by: David Howells <dhowells@redhat.com>
2020-06-16 16:26:57 +01:00
David Howells
9bd87ec631 afs: Fix yfs_fs_fetch_status() to honour vnode selector
Fix yfs_fs_fetch_status() to honour the vnode selector in
op->fetch_status.which as does afs_fs_fetch_status() that allows
afs_do_lookup() to use this as an alternative to the InlineBulkStatus RPC
call if not implemented by the server.

This doesn't matter in the current code as YFS servers always implement
InlineBulkStatus, but a subsequent will call it on YFS servers too in some
circumstances.

Fixes: e49c7b2f6d ("afs: Build an abstraction around an "operation" concept")
Signed-off-by: David Howells <dhowells@redhat.com>
2020-06-16 16:26:57 +01:00
David Howells
6c85cacc8c afs: Remove yfs_fs_fetch_file_status() as it's not used
Remove yfs_fs_fetch_file_status() as it's no longer used.

Signed-off-by: David Howells <dhowells@redhat.com>
2020-06-16 16:26:57 +01:00
David Howells
4ec89596d0 afs: Fix the mapping of the UAEOVERFLOW abort code
Abort code UAEOVERFLOW is returned when we try and set a time that's out of
range, but it's currently mapped to EREMOTEIO by the default case.

Fix UAEOVERFLOW to map instead to EOVERFLOW.

Found with the generic/258 xfstest.  Note that the test is wrong as it
assumes that the filesystem will support a pre-UNIX-epoch date.

Fixes: 1eda8bab70 ("afs: Add support for the UAE error table")
Signed-off-by: David Howells <dhowells@redhat.com>
2020-06-15 15:41:03 +01:00
David Howells
793fe82ee3 afs: Fix truncation issues and mmap writeback size
Fix the following issues:

 (1) Fix writeback to reduce the size of a store operation to i_size,
     effectively discarding the extra data.

     The problem comes when afs_page_mkwrite() records that a page is about
     to be modified by mmap().  It doesn't know what bits of the page are
     going to be modified, so it records the whole page as being dirty
     (this is stored in page->private as start and end offsets).

     Without this, the marshalling for the store to the server extends the
     size of the file to the end of the page (in afs_fs_store_data() and
     yfs_fs_store_data()).

 (2) Fix setattr to actually truncate the pagecache, thereby clearing
     the discarded part of a file.

 (3) Fix setattr to check that the new size is okay and to disable
     ATTR_SIZE if i_size wouldn't change.

 (4) Force i_size to be updated as the result of a truncate.

 (5) Don't truncate if ATTR_SIZE is not set.

 (6) Call pagecache_isize_extended() if the file was enlarged.

Note that truncate_set_size() isn't used because the setting of i_size is
done inside afs_vnode_commit_status() under the vnode->cb_lock.

Found with the generic/029 and generic/393 xfstests.

Fixes: 31143d5d51 ("AFS: implement basic file write support")
Fixes: 4343d00872 ("afs: Get rid of the afs_writeback record")
Signed-off-by: David Howells <dhowells@redhat.com>
2020-06-15 15:41:02 +01:00
David Howells
da8d075512 afs: Concoct ctimes
The in-kernel afs filesystem ignores ctime because the AFS fileserver
protocol doesn't support ctimes.  This, however, causes various xfstests to
fail.

Work around this by:

 (1) Setting ctime to attr->ia_ctime in afs_setattr().

 (2) Not ignoring ATTR_MTIME_SET, ATTR_TIMES_SET and ATTR_TOUCH settings.

 (3) Setting the ctime from the server mtime when on the target file when
     creating a hard link to it.

 (4) Setting the ctime on directories from their revised mtimes when
     renaming/moving a file.

Found by the generic/221 and generic/309 xfstests.

Signed-off-by: David Howells <dhowells@redhat.com>
2020-06-15 15:41:02 +01:00
David Howells
3f4aa98181 afs: Fix EOF corruption
When doing a partial writeback, afs_write_back_from_locked_page() may
generate an FS.StoreData RPC request that writes out part of a file when a
file has been constructed from pieces by doing seek, write, seek, write,
... as is done by ld.

The FS.StoreData RPC is given the current i_size as the file length, but
the server basically ignores it unless the data length is 0 (in which case
it's just a truncate operation).  The revised file length returned in the
result of the RPC may then not reflect what we suggested - and this leads
to i_size getting moved backwards - which causes issues later.

Fix the client to take account of this by ignoring the returned file size
unless the data version number jumped unexpectedly - in which case we're
going to have to clear the pagecache and reload anyway.

This can be observed when doing a kernel build on an AFS mount.  The
following pair of commands produce the issue:

  ld -m elf_x86_64 -z max-page-size=0x200000 --emit-relocs \
      -T arch/x86/realmode/rm/realmode.lds \
      arch/x86/realmode/rm/header.o \
      arch/x86/realmode/rm/trampoline_64.o \
      arch/x86/realmode/rm/stack.o \
      arch/x86/realmode/rm/reboot.o \
      -o arch/x86/realmode/rm/realmode.elf
  arch/x86/tools/relocs --realmode \
      arch/x86/realmode/rm/realmode.elf \
      >arch/x86/realmode/rm/realmode.relocs

This results in the latter giving:

	Cannot read ELF section headers 0/18: Success

as the realmode.elf file got corrupted.

The sequence of events can also be driven with:

	xfs_io -t -f \
		-c "pwrite -S 0x58 0 0x58" \
		-c "pwrite -S 0x59 10000 1000" \
		-c "close" \
		/afs/example.com/scratch/a

Fixes: 31143d5d51 ("AFS: implement basic file write support")
Signed-off-by: David Howells <dhowells@redhat.com>
2020-06-15 15:41:02 +01:00
David Howells
1f32ef7989 afs: afs_write_end() should change i_size under the right lock
Fix afs_write_end() to change i_size under vnode->cb_lock rather than
->wb_lock so that it doesn't race with afs_vnode_commit_status() and
afs_getattr().

The ->wb_lock is only meant to guard access to ->wb_keys which isn't
accessed by that piece of code.

Fixes: 4343d00872 ("afs: Get rid of the afs_writeback record")
Signed-off-by: David Howells <dhowells@redhat.com>
2020-06-15 15:41:02 +01:00
David Howells
bb41348928 afs: Fix non-setting of mtime when writing into mmap
The mtime on an inode needs to be updated when a write is made into an
mmap'ed section.  There are three ways in which this could be done: update
it when page_mkwrite is called, update it when a page is changed from dirty
to writeback or leave it to the server and fix the mtime up from the reply
to the StoreData RPC.

Found with the generic/215 xfstest.

Fixes: 1cf7a1518a ("afs: Implement shared-writeable mmap")
Signed-off-by: David Howells <dhowells@redhat.com>
2020-06-15 15:41:02 +01:00
David Howells
b3597945c8 afs: Fix afs_store_data() to set mtime in new operation descriptor
Fix afs_store_data() so that it sets the mtime in the new operation
descriptor otherwise the mtime on the server gets set to 0 when a write is
stored to the server.

Fixes: e49c7b2f6d ("afs: Build an abstraction around an "operation" concept")
Reported-by: Dave Botsch <botsch@cnf.cornell.edu>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-11 16:04:30 -07:00
David Howells
c68421bbad afs: Make afs_zap_data() static
Make afs_zap_data() static as it's only used in the file in which it is
defined.

Signed-off-by: David Howells <dhowells@redhat.com>
2020-06-09 18:17:14 +01:00
David Howells
4a06fa5403 afs: Remove afs_zero_fid as it's not used
Remove afs_zero_fid as it's not used.

Signed-off-by: David Howells <dhowells@redhat.com>
2020-06-09 18:17:14 +01:00
David Howells
fed79fd783 afs: Fix debugging statements with %px to be %p
Fix a couple of %px to be %p in debugging statements.

Fixes: e49c7b2f6d ("afs: Build an abstraction around an "operation" concept")
Fixes: 8a070a9648 ("afs: Detect cell aliases 1 - Cells with root volumes")
Reported-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
2020-06-09 18:17:14 +01:00
David Howells
9ca0652596 afs: Fix use of BUG()
Fix afs_compare_addrs() to use WARN_ON(1) instead of BUG() and return 1
(ie. srx_a > srx_b).

There's no point trying to put actual error handling in as this should not
occur unless a new transport address type is allowed by AFS.  And even if
it does, in this particular case, it'll just never match unknown types of
addresses.  This BUG() was more of a 'you need to add a case here'
indicator.

Reported-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
2020-06-09 17:21:03 +01:00
David Howells
5749ce92c4 afs: Fix file locking
Fix AFS file locking to use the correct vnode pointer and remove a member
of the afs_operation struct that is never set, but it is read and followed,
causing an oops.

This can be triggered by:

	flock -s /afs/example.com/foo sleep 1

when it calls the kernel to get a file lock.

Fixes: e49c7b2f6d ("afs: Build an abstraction around an "operation" concept")
Reported-by: Dave Botsch <botsch@cnf.cornell.edu>
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Dave Botsch <botsch@cnf.cornell.edu>
2020-06-09 15:22:06 +01:00
Zhihao Cheng
2ca068be09 afs: Fix memory leak in afs_put_sysnames()
Fix afs_put_sysnames() to actually free the specified afs_sysnames
object after its reference count has been decreased to zero and
its contents have been released.

Fixes: 6f8880d8e6 ("afs: Implement @sys substitution handling")
Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2020-06-09 15:22:06 +01:00
Linus Torvalds
9daa0a27a0 AFS Changes
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCAAdFiEEqG5UsNXhtOCrfGQP+7dXa6fLC2sFAl7ZC5kACgkQ+7dXa6fL
 C2uv9A/+NKlTSXyv2ZuvtmXADelndcXJ+nC+3bwI7Jh43aa8uCCsAVYD0VE+dxor
 Ingj/LUJ2sjjp6RXCeeqqETXCoCVt0zK2g216+An7k84KJ+ms+MDa8dNN7l6280S
 1jw4hnT0+g9Ln6elgqBroV980MJC2NGL0Eaete8zFO8UqYZy5w1ge0HfGck2l45U
 2lr6egCWYSUPmtFKXJnLV8luwRvq7DzvTk9WrJu3kwOjaY1AQP1+1VpdhChJLrRc
 /4Ddy1On5IXiFrPi5OtHA422bfirUpIv2HbmI047W9uiZ05MiXwSvNS1qJLTa1AA
 T/SK88d3FCeSYw3olAne2kEl9uewvGByr98fDKFOcDHZj18abd9/VtUp33RXxYBy
 lN2wqlWP++LlZ4sMCbbvLXX8OB1tekQzWQC0vJ5rhRSgveOlhL9TLG2Y05xokFs+
 AwK8zTlDIZ6Pa/JIHfp2E0ZhXEazWTSmP+d7NkgzF0iiORukvsmxjOVUZC4+UCqK
 rYN6goJ5g8qpejRv5NhfP6/olb1NK33f/F2QSSFfxv9zda4HNlayvcoSnFrdUEnt
 IfBhSKPkeDVWs1yse7glDuw19tHp94B9UYwJ46qfHngQPArgy+gp23d0cSy41Pr5
 FRQ23eNvBWIP4srt1gSCBexSGA1h/ACji41CPTJbF2jg5uWFAUE=
 =YVwD
 -----END PGP SIGNATURE-----

Merge tag 'afs-next-20200604' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

Pull AFS updates from David Howells:
 "There's some core VFS changes which affect a couple of filesystems:

   - Make the inode hash table RCU safe and providing some RCU-safe
     accessor functions. The search can then be done without taking the
     inode_hash_lock. Care must be taken because the object may be being
     deleted and no wait is made.

   - Allow iunique() to avoid taking the inode_hash_lock.

   - Allow AFS's callback processing to avoid taking the inode_hash_lock
     when using the inode table to find an inode to notify.

   - Improve Ext4's time updating. Konstantin Khlebnikov said "For now,
     I've plugged this issue with try-lock in ext4 lazy time update.
     This solution is much better."

  Then there's a set of changes to make a number of improvements to the
  AFS driver:

   - Improve callback (ie. third party change notification) processing
     by:

      (a) Relying more on the fact we're doing this under RCU and by
          using fewer locks. This makes use of the RCU-based inode
          searching outlined above.

      (b) Moving to keeping volumes in a tree indexed by volume ID
          rather than a flat list.

      (c) Making the server and volume records logically part of the
          cell. This means that a server record now points directly at
          the cell and the tree of volumes is there. This removes an N:M
          mapping table, simplifying things.

   - Improve keeping NAT or firewall channels open for the server
     callbacks to reach the client by actively polling the fileserver on
     a timed basis, instead of only doing it when we have an operation
     to process.

   - Improving detection of delayed or lost callbacks by including the
     parent directory in the list of file IDs to be queried when doing a
     bulk status fetch from lookup. We can then check to see if our copy
     of the directory has changed under us without us getting notified.

   - Determine aliasing of cells (such as a cell that is pointed to be a
     DNS alias). This allows us to avoid having ambiguity due to
     apparently different cells using the same volume and file servers.

   - Improve the fileserver rotation to do more probing when it detects
     that all of the addresses to a server are listed as non-responsive.
     It's possible that an address that previously stopped responding
     has become responsive again.

  Beyond that, lay some foundations for making some calls asynchronous:

   - Turn the fileserver cursor struct into a general operation struct
     and hang the parameters off of that rather than keeping them in
     local variables and hang results off of that rather than the call
     struct.

   - Implement some general operation handling code and simplify the
     callers of operations that affect a volume or a volume component
     (such as a file). Most of the operation is now done by core code.

   - Operations are supplied with a table of operations to issue
     different variants of RPCs and to manage the completion, where all
     the required data is held in the operation object, thereby allowing
     these to be called from a workqueue.

   - Put the standard "if (begin), while(select), call op, end" sequence
     into a canned function that just emulates the current behaviour for
     now.

  There are also some fixes interspersed:

   - Don't let the EACCES from ICMP6 mapping reach the user as such,
     since it's confusing as to whether it's a filesystem error. Convert
     it to EHOSTUNREACH.

   - Don't use the epoch value acquired through probing a server. If we
     have two servers with the same UUID but in different cells, it's
     hard to draw conclusions from them having different epoch values.

   - Don't interpret the argument to the CB.ProbeUuid RPC as a
     fileserver UUID and look up a fileserver from it.

   - Deal with servers in different cells having the same UUIDs. In the
     event that a CB.InitCallBackState3 RPC is received, we have to
     break the callback promises for every server record matching that
     UUID.

   - Don't let afs_statfs return values that go below 0.

   - Don't use running fileserver probe state to make server selection
     and address selection decisions on. Only make decisions on final
     state as the running state is cleared at the start of probing"

Acked-by: Al Viro <viro@zeniv.linux.org.uk> (fs/inode.c part)

* tag 'afs-next-20200604' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs: (27 commits)
  afs: Adjust the fileserver rotation algorithm to reprobe/retry more quickly
  afs: Show more a bit more server state in /proc/net/afs/servers
  afs: Don't use probe running state to make decisions outside probe code
  afs: Fix afs_statfs() to not let the values go below zero
  afs: Fix the by-UUID server tree to allow servers with the same UUID
  afs: Reorganise volume and server trees to be rooted on the cell
  afs: Add a tracepoint to track the lifetime of the afs_volume struct
  afs: Detect cell aliases 3 - YFS Cells with a canonical cell name op
  afs: Detect cell aliases 2 - Cells with no root volumes
  afs: Detect cell aliases 1 - Cells with root volumes
  afs: Implement client support for the YFSVL.GetCellName RPC op
  afs: Retain more of the VLDB record for alias detection
  afs: Fix handling of CB.ProbeUuid cache manager op
  afs: Don't get epoch from a server because it may be ambiguous
  afs: Build an abstraction around an "operation" concept
  afs: Rename struct afs_fs_cursor to afs_operation
  afs: Remove the error argument from afs_protocol_error()
  afs: Set error flag rather than return error from file status decode
  afs: Make callback processing more efficient.
  afs: Show more information in /proc/net/afs/servers
  ...
2020-06-05 16:26:36 -07:00
David Howells
8409f67b64 afs: Adjust the fileserver rotation algorithm to reprobe/retry more quickly
Adjust the fileserver rotation algorithm so that if we've tried all the
addresses on a server (cumulatively over multiple operations) until we've
run out of untried addresses, immediately reprobe all that server's
interfaces and retry the op at least once before we move onto the next
server.

Signed-off-by: David Howells <dhowells@redhat.com>
2020-06-04 15:37:58 +01:00
David Howells
32275d3f75 afs: Show more a bit more server state in /proc/net/afs/servers
Display more information about the state of a server record, including the
flags, rtt and break counter plus the probe state for each server in
/proc/net/afs/servers.

Rearrange the server flags a bit to make them easier to read at a glance in
the proc file.

Signed-off-by: David Howells <dhowells@redhat.com>
2020-06-04 15:37:58 +01:00
David Howells
f3c130e6e6 afs: Don't use probe running state to make decisions outside probe code
Don't use the running state for fileserver probes to make decisions about
which server to use as the state is cleared at the start of a probe and
also intermediate values might be misleading.

Instead, add a separate 'latest known' rtt in the afs_server struct and a
flag to indicate if the server is known to be responding and update these
as and when we know what to change them to.

Signed-off-by: David Howells <dhowells@redhat.com>
2020-06-04 15:37:58 +01:00
David Howells
f11a016a85 afs: Fix afs_statfs() to not let the values go below zero
Fix afs_statfs() so that the value for f_bavail and f_bfree don't go
"negative" if the number of blocks in use by a volume exceeds the max quota
for that volume.

Signed-off-by: David Howells <dhowells@redhat.com>
2020-06-04 15:37:58 +01:00
David Howells
3c4c4075fc afs: Fix the by-UUID server tree to allow servers with the same UUID
Whilst it shouldn't happen, it is possible for multiple fileservers to
share a UUID, particularly if an entire cell has been duplicated, UUIDs and
all.  In such a case, it's not necessarily possible to map the effect of
the CB.InitCallBackState3 incoming RPC to a specific server unambiguously
by UUID and thus to a specific cell.

Indeed, there's a problem whereby multiple server records may need to
occupy the same spot in the rb_tree rooted in the afs_net struct.

Fix this by allowing servers to form a list, with the head of the list in
the tree.  When the front entry in the list is removed, the second in the
list just replaces it.  afs_init_callback_state() then just goes down the
line, poking each server in the list.

This means that some servers will be unnecessarily poked, unfortunately.
An alternative would be to route by call parameters.

Reported-by: Jeffrey Altman <jaltman@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Fixes: d2ddc776a4 ("afs: Overhaul volume and server record caching and fileserver rotation")
2020-06-04 15:37:57 +01:00
David Howells
20325960f8 afs: Reorganise volume and server trees to be rooted on the cell
Reorganise afs_volume objects such that they're in a tree keyed on volume
ID, rooted at on an afs_cell object rather than being in multiple trees,
each of which is rooted on an afs_server object.

afs_server structs become per-cell and acquire a pointer to the cell.

The process of breaking a callback then starts with finding the server by
its network address, following that to the cell and then looking up each
volume ID in the volume tree.

This is simpler than the afs_vol_interest/afs_cb_interest N:M mapping web
and allows those structs and the code for maintaining them to be simplified
or removed.

It does make a couple of things a bit more tricky, though:

 (1) Operations now start with a volume, not a server, so there can be more
     than one answer as to whether or not the server we'll end up using
     supports the FS.InlineBulkStatus RPC.

 (2) CB RPC operations that specify the server UUID.  There's still a tree
     of servers by UUID on the afs_net struct, but the UUIDs in it aren't
     guaranteed unique.

Signed-off-by: David Howells <dhowells@redhat.com>
2020-06-04 15:37:57 +01:00
David Howells
cca37d45d5 afs: Add a tracepoint to track the lifetime of the afs_volume struct
Add a tracepoint to track the lifetime of the afs_volume struct.

Signed-off-by: David Howells <dhowells@redhat.com>
2020-06-04 15:37:57 +01:00
David Howells
6dfdf5369c afs: Detect cell aliases 3 - YFS Cells with a canonical cell name op
YFS Volume Location servers have an operation by which the cell name may be
queried.  Use this to find out what a YFS server thinks the canonical cell
name should be.

Signed-off-by: David Howells <dhowells@redhat.com>
2020-06-04 15:37:57 +01:00
David Howells
6ef350b184 afs: Detect cell aliases 2 - Cells with no root volumes
Implement the second phase of cell alias detection.  This part handles
alias detection for cells that don't have root.cell volumes and so we have
to find some other volume or fileserver to query.

We take the first volume from each such cell and attempt to look it up in
the new cell.  If found, we compare the records, if they are the same, we
judge the cell names to be aliases.

Signed-off-by: David Howells <dhowells@redhat.com>
2020-06-04 15:37:57 +01:00
David Howells
8a070a9648 afs: Detect cell aliases 1 - Cells with root volumes
Put in the first phase of cell alias detection.  This part handles alias
detection for cells that have root.cell volumes (which is expected to be
likely).

When a cell becomes newly active, it is probed for its root.cell volume,
and if it has one, this volume is compared against other root.cell volumes
to find out if the list of fileserver UUIDs have any in common - and if
that's the case, do the address lists of those fileservers have any
addresses in common.  If they do, the new cell is adjudged to be an alias
of the old cell and the old cell is used instead.

Comparing is aided by the server list in struct afs_server_list being
sorted in UUID order and the addresses in the fileserver address lists
being sorted in address order.

The cell then retains the afs_volume object for the root.cell volume, even
if it's not mounted for future alias checking.

This necessary because:

 (1) Whilst fileservers have UUIDs that are meant to be globally unique, in
     practice they are not because cells get cloned without changing the
     UUIDs - so afs_server records need to be per cell.

 (2) Sometimes the DNS is used to make cell aliases - but if we don't know
     they're the same, we may end up with multiple superblocks and multiple
     afs_server records for the same thing, impairing our ability to
     deliver callback notifications of third party changes

 (3) The fileserver RPC API doesn't contain the cell name, so it can't tell
     us which cell it's notifying and can't see that a change made to to
     one cell should notify the same client that's also accessed as the
     other cell.

Reported-by: Jeffrey Altman <jaltman@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2020-06-04 15:37:57 +01:00
David Howells
c3e9f88826 afs: Implement client support for the YFSVL.GetCellName RPC op
Implement client support for the YFSVL.GetCellName RPC operation by which
YFS permits the canonical cell name to be queried from a VL server.

Signed-off-by: David Howells <dhowells@redhat.com>
2020-06-04 15:37:57 +01:00
David Howells
194d28cf19 afs: Retain more of the VLDB record for alias detection
Save more bits from the volume location database record obtained for a
server so that we can use this information in cell alias detection.

Signed-off-by: David Howells <dhowells@redhat.com>
2020-06-04 15:37:57 +01:00
David Howells
3120c170ef afs: Fix handling of CB.ProbeUuid cache manager op
The AFS filesystem driver is handling the CB.ProbeUuid request incorrectly.
The UUID presented in the request is that of the cache manager, not the
fileserver, so afs_deliver_cb_probe_uuid() shouldn't be using that UUID to
look up the server.

Fix this by looking up the server by address instead.

Signed-off-by: David Howells <dhowells@redhat.com>
2020-06-04 15:37:57 +01:00
David Howells
44746355cc afs: Don't get epoch from a server because it may be ambiguous
Don't get the epoch from a server, particularly one that we're looking up
by UUID, as UUIDs may be ambiguous and may map to more than one server - so
we can't draw any conclusions from it.

Reported-by: Jeffrey Altman <jaltman@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2020-06-04 15:37:56 +01:00
David Howells
e49c7b2f6d afs: Build an abstraction around an "operation" concept
Turn the afs_operation struct into the main way that most fileserver
operations are managed.  Various things are added to the struct, including
the following:

 (1) All the parameters and results of the relevant operations are moved
     into it, removing corresponding fields from the afs_call struct.
     afs_call gets a pointer to the op.

 (2) The target volume is made the main focus of the operation, rather than
     the target vnode(s), and a bunch of op->vnode->volume are made
     op->volume instead.

 (3) Two vnode records are defined (op->file[]) for the vnode(s) involved
     in most operations.  The vnode record (struct afs_vnode_param)
     contains:

	- The vnode pointer.

	- The fid of the vnode to be included in the parameters or that was
          returned in the reply (eg. FS.MakeDir).

	- The status and callback information that may be returned in the
     	  reply about the vnode.

	- Callback break and data version tracking for detecting
          simultaneous third-parth changes.

 (4) Pointers to dentries to be updated with new inodes.

 (5) An operations table pointer.  The table includes pointers to functions
     for issuing AFS and YFS-variant RPCs, handling the success and abort
     of an operation and handling post-I/O-lock local editing of a
     directory.

To make this work, the following function restructuring is made:

 (A) The rotation loop that issues calls to fileservers that can be found
     in each function that wants to issue an RPC (such as afs_mkdir()) is
     extracted out into common code, in a new file called fs_operation.c.

 (B) The rotation loops, such as the one in afs_mkdir(), are replaced with
     a much smaller piece of code that allocates an operation, sets the
     parameters and then calls out to the common code to do the actual
     work.

 (C) The code for handling the success and failure of an operation are
     moved into operation functions (as (5) above) and these are called
     from the core code at appropriate times.

 (D) The pseudo inode getting stuff used by the dynamic root code is moved
     over into dynroot.c.

 (E) struct afs_iget_data is absorbed into the operation struct and
     afs_iget() expects to be given an op pointer and a vnode record.

 (F) Point (E) doesn't work for the root dir of a volume, but we know the
     FID in advance (it's always vnode 1, unique 1), so a separate inode
     getter, afs_root_iget(), is provided to special-case that.

 (G) The inode status init/update functions now also take an op and a vnode
     record.

 (H) The RPC marshalling functions now, for the most part, just take an
     afs_operation struct as their only argument.  All the data they need
     is held there.  The result delivery functions write their answers
     there as well.

 (I) The call is attached to the operation and then the operation core does
     the waiting.

And then the new operation code is, for the moment, made to just initialise
the operation, get the appropriate vnode I/O locks and do the same rotation
loop as before.

This lays the foundation for the following changes in the future:

 (*) Overhauling the rotation (again).

 (*) Support for asynchronous I/O, where the fileserver rotation must be
     done asynchronously also.

Signed-off-by: David Howells <dhowells@redhat.com>
2020-06-04 15:37:17 +01:00
Linus Torvalds
cb8e59cc87 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
Pull networking updates from David Miller:

 1) Allow setting bluetooth L2CAP modes via socket option, from Luiz
    Augusto von Dentz.

 2) Add GSO partial support to igc, from Sasha Neftin.

 3) Several cleanups and improvements to r8169 from Heiner Kallweit.

 4) Add IF_OPER_TESTING link state and use it when ethtool triggers a
    device self-test. From Andrew Lunn.

 5) Start moving away from custom driver versions, use the globally
    defined kernel version instead, from Leon Romanovsky.

 6) Support GRO vis gro_cells in DSA layer, from Alexander Lobakin.

 7) Allow hard IRQ deferral during NAPI, from Eric Dumazet.

 8) Add sriov and vf support to hinic, from Luo bin.

 9) Support Media Redundancy Protocol (MRP) in the bridging code, from
    Horatiu Vultur.

10) Support netmap in the nft_nat code, from Pablo Neira Ayuso.

11) Allow UDPv6 encapsulation of ESP in the ipsec code, from Sabrina
    Dubroca. Also add ipv6 support for espintcp.

12) Lots of ReST conversions of the networking documentation, from Mauro
    Carvalho Chehab.

13) Support configuration of ethtool rxnfc flows in bcmgenet driver,
    from Doug Berger.

14) Allow to dump cgroup id and filter by it in inet_diag code, from
    Dmitry Yakunin.

15) Add infrastructure to export netlink attribute policies to
    userspace, from Johannes Berg.

16) Several optimizations to sch_fq scheduler, from Eric Dumazet.

17) Fallback to the default qdisc if qdisc init fails because otherwise
    a packet scheduler init failure will make a device inoperative. From
    Jesper Dangaard Brouer.

18) Several RISCV bpf jit optimizations, from Luke Nelson.

19) Correct the return type of the ->ndo_start_xmit() method in several
    drivers, it's netdev_tx_t but many drivers were using
    'int'. From Yunjian Wang.

20) Add an ethtool interface for PHY master/slave config, from Oleksij
    Rempel.

21) Add BPF iterators, from Yonghang Song.

22) Add cable test infrastructure, including ethool interfaces, from
    Andrew Lunn. Marvell PHY driver is the first to support this
    facility.

23) Remove zero-length arrays all over, from Gustavo A. R. Silva.

24) Calculate and maintain an explicit frame size in XDP, from Jesper
    Dangaard Brouer.

25) Add CAP_BPF, from Alexei Starovoitov.

26) Support terse dumps in the packet scheduler, from Vlad Buslov.

27) Support XDP_TX bulking in dpaa2 driver, from Ioana Ciornei.

28) Add devm_register_netdev(), from Bartosz Golaszewski.

29) Minimize qdisc resets, from Cong Wang.

30) Get rid of kernel_getsockopt and kernel_setsockopt in order to
    eliminate set_fs/get_fs calls. From Christoph Hellwig.

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2517 commits)
  selftests: net: ip_defrag: ignore EPERM
  net_failover: fixed rollback in net_failover_open()
  Revert "tipc: Fix potential tipc_aead refcnt leak in tipc_crypto_rcv"
  Revert "tipc: Fix potential tipc_node refcnt leak in tipc_rcv"
  vmxnet3: allow rx flow hash ops only when rss is enabled
  hinic: add set_channels ethtool_ops support
  selftests/bpf: Add a default $(CXX) value
  tools/bpf: Don't use $(COMPILE.c)
  bpf, selftests: Use bpf_probe_read_kernel
  s390/bpf: Use bcr 0,%0 as tail call nop filler
  s390/bpf: Maintain 8-byte stack alignment
  selftests/bpf: Fix verifier test
  selftests/bpf: Fix sample_cnt shared between two threads
  bpf, selftests: Adapt cls_redirect to call csum_level helper
  bpf: Add csum_level helper for fixing up csum levels
  bpf: Fix up bpf_skb_adjust_room helper's skb csum setting
  sfc: add missing annotation for efx_ef10_try_update_nic_stats_vf()
  crypto/chtls: IPv6 support for inline TLS
  Crypto/chcr: Fixes a coccinile check error
  Crypto/chcr: Fixes compilations warnings
  ...
2020-06-03 16:27:18 -07:00
Linus Torvalds
b23c4771ff A fair amount of stuff this time around, dominated by yet another massive
set from Mauro toward the completion of the RST conversion.  I *really*
 hope we are getting close to the end of this.  Meanwhile, those patches
 reach pretty far afield to update document references around the tree;
 there should be no actual code changes there.  There will be, alas, more of
 the usual trivial merge conflicts.
 
 Beyond that we have more translations, improvements to the sphinx
 scripting, a number of additions to the sysctl documentation, and lots of
 fixes.
 -----BEGIN PGP SIGNATURE-----
 
 iQFDBAABCAAtFiEEIw+MvkEiF49krdp9F0NaE2wMflgFAl7VId8PHGNvcmJldEBs
 d24ubmV0AAoJEBdDWhNsDH5Yq/gH/iaDgirQZV6UZ2v9sfwQNYolNpf2sKAuOZjd
 bPFB7WJoMQbKwQEvYrAUL2+5zPOcLYuIfzyOfo1BV1py+EyKbACcKjI4AedxfJF7
 +NchmOBhlEqmEhzx2U08HRc4/8J223WG17fJRVsV3p+opJySexSFeQucfOciX5NR
 RUCxweWWyg/FgyqjkyMMTtsePqZPmcT5dWTlVXISlbWzcv5NFhuJXnSrw8Sfzcmm
 SJMzqItv3O+CabnKQ8kMLV2PozXTMfjeWH47ZUK0Y8/8PP9+cvqwFzZ0UDQJ1Xaz
 oyW/TqmunaXhfMsMFeFGSwtfgwRHvXdxkQdtwNHvo1dV4dzTvDw=
 =fDC/
 -----END PGP SIGNATURE-----

Merge tag 'docs-5.8' of git://git.lwn.net/linux

Pull documentation updates from Jonathan Corbet:
 "A fair amount of stuff this time around, dominated by yet another
  massive set from Mauro toward the completion of the RST conversion. I
  *really* hope we are getting close to the end of this. Meanwhile,
  those patches reach pretty far afield to update document references
  around the tree; there should be no actual code changes there. There
  will be, alas, more of the usual trivial merge conflicts.

  Beyond that we have more translations, improvements to the sphinx
  scripting, a number of additions to the sysctl documentation, and lots
  of fixes"

* tag 'docs-5.8' of git://git.lwn.net/linux: (130 commits)
  Documentation: fixes to the maintainer-entry-profile template
  zswap: docs/vm: Fix typo accept_threshold_percent in zswap.rst
  tracing: Fix events.rst section numbering
  docs: acpi: fix old http link and improve document format
  docs: filesystems: add info about efivars content
  Documentation: LSM: Correct the basic LSM description
  mailmap: change email for Ricardo Ribalda
  docs: sysctl/kernel: document unaligned controls
  Documentation: admin-guide: update bug-hunting.rst
  docs: sysctl/kernel: document ngroups_max
  nvdimm: fixes to maintainter-entry-profile
  Documentation/features: Correct RISC-V kprobes support entry
  Documentation/features: Refresh the arch support status files
  Revert "docs: sysctl/kernel: document ngroups_max"
  docs: move locking-specific documents to locking/
  docs: move digsig docs to the security book
  docs: move the kref doc into the core-api book
  docs: add IRQ documentation at the core-api book
  docs: debugging-via-ohci1394.txt: add it to the core-api book
  docs: fix references for ipmi.rst file
  ...
2020-06-01 15:45:27 -07:00
David Howells
a310082f6d afs: Rename struct afs_fs_cursor to afs_operation
As a prelude to implementing asynchronous fileserver operations in the afs
filesystem, rename struct afs_fs_cursor to afs_operation.

This struct is going to form the core of the operation management and is
going to acquire more members in later.

Signed-off-by: David Howells <dhowells@redhat.com>
2020-05-31 15:19:52 +01:00
David Howells
7126ead910 afs: Remove the error argument from afs_protocol_error()
Remove the error argument from afs_protocol_error() as it's always
-EBADMSG.

Signed-off-by: David Howells <dhowells@redhat.com>
2020-05-31 15:19:52 +01:00
David Howells
38355eec6a afs: Set error flag rather than return error from file status decode
Set a flag in the call struct to indicate an unmarshalling error rather
than return and handle an error from the decoding of file statuses.  This
flag is checked on a successful return from the delivery function.

Signed-off-by: David Howells <dhowells@redhat.com>
2020-05-31 15:19:51 +01:00
David Howells
8230fd8217 afs: Make callback processing more efficient.
afs_vol_interest objects represent the volume IDs currently being accessed
from a fileserver.  These hold lists of afs_cb_interest objects that
repesent the superblocks using that volume ID on that server.

When a callback notification from the server telling of a modification by
another client arrives, the volume ID specified in the notification is
looked up in the server's afs_vol_interest list.  Through the
afs_cb_interest list, the relevant superblocks can be iterated over and the
specific inode looked up and marked in each one.

Make the following efficiency improvements:

 (1) Hold rcu_read_lock() over the entire processing rather than locking it
     each time.

 (2) Do all the callbacks for each vid together rather than individually.
     Each volume then only needs to be looked up once.

 (3) afs_vol_interest objects are now stored in an rb_tree rather than a
     flat list to reduce the lookup step count.

 (4) afs_vol_interest lookup is now done with RCU, but because it's in an
     rb_tree which may rotate under us, a seqlock is used so that if it
     changes during the walk, we repeat the walk with a lock held.

With this and the preceding patch which adds RCU-based lookups in the inode
cache, target volumes/vnodes can be taken without the need to take any
locks, except on the target itself.

Signed-off-by: David Howells <dhowells@redhat.com>
2020-05-31 15:19:51 +01:00
David Howells
6d043a5782 afs: Show more information in /proc/net/afs/servers
Show more information in /proc/net/afs/servers to make it easier to see
what's going on with the server probing.

Signed-off-by: David Howells <dhowells@redhat.com>
2020-05-31 15:19:51 +01:00
David Howells
f6cbb368bc afs: Actively poll fileservers to maintain NAT or firewall openings
When an AFS client accesses a file, it receives a limited-duration callback
promise that the server will notify it if another client changes a file.
This callback duration can be a few hours in length.

If a client mounts a volume and then an application prevents it from being
unmounted, say by chdir'ing into it, but then does nothing for some time,
the rxrpc_peer record will expire and rxrpc-level keepalive will cease.

If there is NAT or a firewall between the client and the server, the route
back for the server may close after a comparatively short duration, meaning
that attempts by the server to notify the client may then bounce.

The client, however, may (so far as it knows) still have a valid unexpired
promise and will then rely on its cached data and will not see changes made
on the server by a third party until it incidentally rechecks the status or
the promise needs renewal.

To deal with this, the client needs to regularly probe the server.  This
has two effects: firstly, it keeps a route open back for the server, and
secondly, it causes the server to disgorge any notifications that got
queued up because they couldn't be sent.

Fix this by adding a mechanism to emit regular probes.

Two levels of probing are made available: Under normal circumstances the
'slow' queue will be used for a fileserver - this just probes the preferred
address once every 5 mins or so; however, if server fails to respond to any
probes, the server will shift to the 'fast' queue from which all its
interfaces will be probed every 30s.  When it finally responds, the record
will switch back to the slow queue.

Further notes:

 (1) Probing is now no longer driven from the fileserver rotation
     algorithm.

 (2) Probes are dispatched to all interfaces on a fileserver when that an
     afs_server object is set up to record it.

 (3) The afs_server object is removed from the probe queues when we start
     to probe it.  afs_is_probing_server() returns true if it's not listed
     - ie. it's undergoing probing.

 (4) The afs_server object is added back on to the probe queue when the
     final outstanding probe completes, but the probed_at time is set when
     we're about to launch a probe so that it's not dependent on the probe
     duration.

 (5) The timer and the work item added for this must be handed a count on
     net->servers_outstanding, which they hand on or release.  This makes
     sure that network namespace cleanup waits for them.

Fixes: d2ddc776a4 ("afs: Overhaul volume and server record caching and fileserver rotation")
Reported-by: Dave Botsch <botsch@cnf.cornell.edu>
Signed-off-by: David Howells <dhowells@redhat.com>
2020-05-31 15:19:51 +01:00
David Howells
977e5f8ed0 afs: Split the usage count on struct afs_server
Split the usage count on the afs_server struct to have an active count that
registers who's actually using it separately from the reference count on
the object.

This allows a future patch to dispatch polling probes without advancing the
"unuse" time into the future each time we emit a probe, which would
otherwise prevent unused server records from expiring.

Included in this:

 (1) The latter part of afs_destroy_server() in which the RCU destruction
     of afs_server objects is invoked and the outstanding server count is
     decremented is split out into __afs_put_server().

 (2) afs_put_server() now calls __afs_put_server() rather then setting the
     management timer.

 (3) The calls begun by afs_fs_give_up_all_callbacks() and
     afs_fs_get_capabilities() can now take a ref on the server record, so
     afs_destroy_server() can just drop its ref and needn't wait for the
     completion of these calls.  They'll put the ref when they're done.

 (4) Because of (3), afs_fs_probe_done() no longer needs to wake up
     afs_destroy_server() with server->probe_outstanding.

 (5) afs_gc_servers can be simplified.  It only needs to check if
     server->active is 0 rather than playing games with the refcount.

 (6) afs_manage_servers() can propose a server for gc if usage == 0 rather
     than if ref == 1.  The gc is effected by (5).

Signed-off-by: David Howells <dhowells@redhat.com>
2020-05-31 15:19:51 +01:00
David Howells
8100680592 afs: Use the serverUnique field in the UVLDB record to reduce rpc ops
The U-version VLDB volume record retrieved by the VL.GetEntryByNameU rpc op
carries a change counter (the serverUnique field) for each fileserver
listed in the record as backing that volume.  This is incremented whenever
the registration details for a fileserver change (such as its address
list).  Note that the same value will be seen in all UVLDB records that
refer to that fileserver.

This should be checked before calling the VL server to re-query the address
list for a fileserver.  If it's the same, there's no point doing the query.

Reported-by: Jeffrey Altman <jaltman@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2020-05-31 15:19:51 +01:00
David Howells
13fcc6356a afs: Always include dir in bulk status fetch from afs_do_lookup()
When a lookup is done in an AFS directory, the filesystem will speculate
and fetch up to 49 other statuses for files in the same directory and fetch
those as well, turning them into inodes or updating inodes that already
exist.

However, occasionally, a callback break might go missing due to NAT timing
out, but the afs filesystem doesn't then realise that the directory is not
up to date.

Alleviate this by using one of the status slots to check the directory in
which the lookup is being done.

Reported-by: Dave Botsch <botsch@cnf.cornell.edu>
Suggested-by: Jeffrey Altman <jaltman@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2020-05-31 15:19:51 +01:00
David Howells
3f19b2ab97 vfs, afs, ext4: Make the inode hash table RCU searchable
Make the inode hash table RCU searchable so that searches that want to
access or modify an inode without taking a ref on that inode can do so
without taking the inode hash table lock.

The main thing this requires is some RCU annotation on the list
manipulation operations.  Inodes are already freed by RCU in most cases.

Users of this interface must take care as the inode may be still under
construction or may be being torn down around them.

There are at least three instances where this can be of use:

 (1) Testing whether the inode number iunique() is going to return is
     currently unique (the iunique_lock is still held).

 (2) Ext4 date stamp updating.

 (3) AFS callback breaking.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
cc: linux-ext4@vger.kernel.org
cc: linux-afs@lists.infradead.org
2020-05-31 15:19:44 +01:00
Christoph Hellwig
298cd88a66 rxrpc: add rxrpc_sock_set_min_security_level
Add a helper to directly set the RXRPC_MIN_SECURITY_LEVEL sockopt from
kernel space without going through a fake uaccess.

Thanks to David Howells for the documentation updates.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-28 11:11:46 -07:00
Linus Torvalds
caffb99b69 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from David Miller:

 1) Fix RCU warnings in ipv6 multicast router code, from Madhuparna
    Bhowmik.

 2) Nexthop attributes aren't being checked properly because of
    mis-initialized iterator, from David Ahern.

 3) Revert iop_idents_reserve() change as it caused performance
    regressions and was just working around what is really a UBSAN bug
    in the compiler. From Yuqi Jin.

 4) Read MAC address properly from ROM in bmac driver (double iteration
    proceeds past end of address array), from Jeremy Kerr.

 5) Add Microsoft Surface device IDs to r8152, from Marc Payne.

 6) Prevent reference to freed SKB in __netif_receive_skb_core(), from
    Boris Sukholitko.

 7) Fix ACK discard behavior in rxrpc, from David Howells.

 8) Preserve flow hash across packet scrubbing in wireguard, from Jason
    A. Donenfeld.

 9) Cap option length properly for SO_BINDTODEVICE in AX25, from Eric
    Dumazet.

10) Fix encryption error checking in kTLS code, from Vadim Fedorenko.

11) Missing BPF prog ref release in flow dissector, from Jakub Sitnicki.

12) dst_cache must be used with BH disabled in tipc, from Eric Dumazet.

13) Fix use after free in mlxsw driver, from Jiri Pirko.

14) Order kTLS key destruction properly in mlx5 driver, from Tariq
    Toukan.

15) Check devm_platform_ioremap_resource() return value properly in
    several drivers, from Tiezhu Yang.

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (71 commits)
  net: smsc911x: Fix runtime PM imbalance on error
  net/mlx4_core: fix a memory leak bug.
  net: ethernet: ti: cpsw: fix ASSERT_RTNL() warning during suspend
  net: phy: mscc: fix initialization of the MACsec protocol mode
  net: stmmac: don't attach interface until resume finishes
  net: Fix return value about devm_platform_ioremap_resource()
  net/mlx5: Fix error flow in case of function_setup failure
  net/mlx5e: CT: Correctly get flow rule
  net/mlx5e: Update netdev txq on completions during closure
  net/mlx5: Annotate mutex destroy for root ns
  net/mlx5: Don't maintain a case of del_sw_func being null
  net/mlx5: Fix cleaning unmanaged flow tables
  net/mlx5: Fix memory leak in mlx5_events_init
  net/mlx5e: Fix inner tirs handling
  net/mlx5e: kTLS, Destroy key object after destroying the TIS
  net/mlx5e: Fix allowed tc redirect merged eswitch offload cases
  net/mlx5: Avoid processing commands before cmdif is ready
  net/mlx5: Fix a race when moving command interface to events mode
  net/mlx5: Add command entry handling completion
  rxrpc: Fix a memory leak in rxkad_verify_response()
  ...
2020-05-23 17:16:18 -07:00
David Howells
8a1d24e1cc rxrpc: Fix a warning
Fix a warning due to an uninitialised variable.

le included from ../fs/afs/fs_probe.c:11:
../fs/afs/fs_probe.c: In function 'afs_fileserver_probe_result':
../fs/afs/internal.h:1453:2: warning: 'rtt_us' may be used uninitialized in this function [-Wmaybe-uninitialized]
 1453 |  printk("[%-6.6s] "FMT"\n", current->comm ,##__VA_ARGS__)
      |  ^~~~~~
../fs/afs/fs_probe.c:35:15: note: 'rtt_us' was declared here

Signed-off-by: David Howells <dhowells@redhat.com>
2020-05-23 00:31:39 +01:00
David Howells
9d1be4f4dc afs: Don't unlock fetched data pages until the op completes successfully
Don't call req->page_done() on each page as we finish filling it with
the data coming from the network.  Whilst this might speed up the
application a bit, it's a problem if there's a network failure and the
operation has to be reissued.

If this happens, an oops occurs because afs_readpages_page_done() clears
the pointer to each page it unlocks and when a retry happens, the
pointers to the pages it wants to fill are now NULL (and the pages have
been unlocked anyway).

Instead, wait till the operation completes successfully and only then
release all the pages after clearing any terminal gap (the server can
give us less data than we requested as we're allowed to ask for more
than is available).

KASAN produces a bug like the following, and even without KASAN, it can
oops and panic.

    BUG: KASAN: wild-memory-access in _copy_to_iter+0x323/0x5f4
    Write of size 1404 at addr 0005088000000000 by task md5sum/5235

    CPU: 0 PID: 5235 Comm: md5sum Not tainted 5.7.0-rc3-fscache+ #250
    Hardware name: ASUS All Series/H97-PLUS, BIOS 2306 10/09/2014
    Call Trace:
     memcpy+0x39/0x58
     _copy_to_iter+0x323/0x5f4
     __skb_datagram_iter+0x89/0x2a6
     skb_copy_datagram_iter+0x129/0x135
     rxrpc_recvmsg_data.isra.0+0x615/0xd42
     rxrpc_kernel_recv_data+0x1e9/0x3ae
     afs_extract_data+0x139/0x33a
     yfs_deliver_fs_fetch_data64+0x47a/0x91b
     afs_deliver_to_call+0x304/0x709
     afs_wait_for_call_to_complete+0x1cc/0x4ad
     yfs_fs_fetch_data+0x279/0x288
     afs_fetch_data+0x1e1/0x38d
     afs_readpages+0x593/0x72e
     read_pages+0xf5/0x21e
     __do_page_cache_readahead+0x128/0x23f
     ondemand_readahead+0x36e/0x37f
     generic_file_buffered_read+0x234/0x680
     new_sync_read+0x109/0x17e
     vfs_read+0xe6/0x138
     ksys_read+0xd8/0x14d
     do_syscall_64+0x6e/0x8a
     entry_SYSCALL_64_after_hwframe+0x49/0xb3

Fixes: 196ee9cd2d ("afs: Make afs_fs_fetch_data() take a list of pages")
Fixes: 30062bd13e ("afs: Implement YFS support in the fs client")
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-05-18 10:29:17 -07:00
David Howells
c410bf0193 rxrpc: Fix the excessive initial retransmission timeout
rxrpc currently uses a fixed 4s retransmission timeout until the RTT is
sufficiently sampled.  This can cause problems with some fileservers with
calls to the cache manager in the afs filesystem being dropped from the
fileserver because a packet goes missing and the retransmission timeout is
greater than the call expiry timeout.

Fix this by:

 (1) Copying the RTT/RTO calculation code from Linux's TCP implementation
     and altering it to fit rxrpc.

 (2) Altering the various users of the RTT to make use of the new SRTT
     value.

 (3) Replacing the use of rxrpc_resend_timeout to use the calculated RTO
     value instead (which is needed in jiffies), along with a backoff.

Notes:

 (1) rxrpc provides RTT samples by matching the serial numbers on outgoing
     DATA packets that have the RXRPC_REQUEST_ACK set and PING ACK packets
     against the reference serial number in incoming REQUESTED ACK and
     PING-RESPONSE ACK packets.

 (2) Each packet that is transmitted on an rxrpc connection gets a new
     per-connection serial number, even for retransmissions, so an ACK can
     be cross-referenced to a specific trigger packet.  This allows RTT
     information to be drawn from retransmitted DATA packets also.

 (3) rxrpc maintains the RTT/RTO state on the rxrpc_peer record rather than
     on an rxrpc_call because many RPC calls won't live long enough to
     generate more than one sample.

 (4) The calculated SRTT value is in units of 8ths of a microsecond rather
     than nanoseconds.

The (S)RTT and RTO values are displayed in /proc/net/rxrpc/peers.

Fixes: 17926a7932 ([AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both"")
Signed-off-by: David Howells <dhowells@redhat.com>
2020-05-11 16:42:28 +01:00
David Howells
c4bfda16d1 afs: Make record checking use TASK_UNINTERRUPTIBLE when appropriate
When an operation is meant to be done uninterruptibly (such as
FS.StoreData), we should not be allowing volume and server record checking
to be interrupted.

Fixes: d2ddc776a4 ("afs: Overhaul volume and server record caching and fileserver rotation")
Signed-off-by: David Howells <dhowells@redhat.com>
2020-04-24 16:33:32 +01:00
David Howells
69cf3978f3 afs: Fix to actually set AFS_SERVER_FL_HAVE_EPOCH
AFS keeps track of the epoch value from the rxrpc protocol to note (a) when
a fileserver appears to have restarted and (b) when different endpoints of
a fileserver do not appear to be associated with the same fileserver
(ie. all probes back from a fileserver from all of its interfaces should
carry the same epoch).

However, the AFS_SERVER_FL_HAVE_EPOCH flag that indicates that we've
received the server's epoch is never set, though it is used.

Fix this to set the flag when we first receive an epoch value from a probe
sent to the filesystem client from the fileserver.

Fixes: 3bf0fb6f33 ("afs: Probe multiple fileservers simultaneously")
Signed-off-by: David Howells <dhowells@redhat.com>
2020-04-24 16:32:49 +01:00
David Howells
be59167c8f afs: Remove some unused bits
Remove three bits:

 (1) afs_server::no_epoch is neither set nor used.

 (2) afs_server::have_result is set and a wakeup is applied to it, but
     nothing looks at it or waits on it.

 (3) afs_vl_dump_edestaddrreq() prints afs_addr_list::probed, but nothing
     sets it for VL servers.

Signed-off-by: David Howells <dhowells@redhat.com>
2020-04-24 16:32:49 +01:00
Mauro Carvalho Chehab
0c1bc6b845 docs: filesystems: fix renamed references
Some filesystem references got broken by a previous patch
series I submitted. Address those.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Acked-by: David Sterba <dsterba@suse.com> # fs/affs/Kconfig
Link: https://lore.kernel.org/r/57318c53008dbda7f6f4a5a9e5787f4d37e8565a.1586881715.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-04-20 15:45:22 -06:00
David Howells
40fc81027f afs: Fix afs_d_validate() to set the right directory version
If a dentry's version is somewhere between invalid_before and the current
directory version, we should be setting it forward to the current version,
not backwards to the invalid_before version.  Note that we're only doing
this at all because dentry::d_fsdata isn't large enough on a 32-bit system.

Fix this by using a separate variable for invalid_before so that we don't
accidentally clobber the current dir version.

Fixes: a4ff7401fb ("afs: Keep track of invalid-before version for dentry coherency")
Signed-off-by: David Howells <dhowells@redhat.com>
2020-04-13 15:09:01 +01:00
David Howells
2105c2820d afs: Fix race between post-modification dir edit and readdir/d_revalidate
AFS directories are retained locally as a structured file, with lookup
being effected by a local search of the file contents.  When a modification
(such as mkdir) happens, the dir file content is modified locally rather
than redownloading the directory.

The directory contents are accessed in a number of ways, with a number of
different locks schemes:

 (1) Download of contents - dvnode->validate_lock/write in afs_read_dir().

 (2) Lookup and readdir - dvnode->validate_lock/read in afs_dir_iterate(),
     downgrading from (1) if necessary.

 (3) d_revalidate of child dentry - dvnode->validate_lock/read in
     afs_do_lookup_one() downgrading from (1) if necessary.

 (4) Edit of dir after modification - page locks on individual dir pages.

Unfortunately, because (4) uses different locking scheme to (1) - (3),
nothing protects against the page being scanned whilst the edit is
underway.  Even download is not safe as it doesn't lock the pages - relying
instead on the validate_lock to serialise as a whole (the theory being that
directory contents are treated as a block and always downloaded as a
block).

Fix this by write-locking dvnode->validate_lock around the edits.  Care
must be taken in the rename case as there may be two different dirs - but
they need not be locked at the same time.  In any case, once the lock is
taken, the directory version must be rechecked, and the edit skipped if a
later version has been downloaded by revalidation (there can't have been
any local changes because the VFS holds the inode lock, but there can have
been remote changes).

Fixes: 63a4681ff3 ("afs: Locally edit directory data for mkdir/create/unlink/...")
Signed-off-by: David Howells <dhowells@redhat.com>
2020-04-13 15:09:01 +01:00
David Howells
3efe55b09a afs: Fix length of dump of bad YFSFetchStatus record
Fix the length of the dump of a bad YFSFetchStatus record.  The function
was copied from the AFS version, but the YFS variant contains bigger fields
and extra information, so expand the dump to match.

Signed-off-by: David Howells <dhowells@redhat.com>
2020-04-13 15:09:01 +01:00
David Howells
b98f0ec91c afs: Fix rename operation status delivery
The afs_deliver_fs_rename() and yfs_deliver_fs_rename() functions both only
decode the second file status returned unless the parent directories are
different - unfortunately, this means that the xdr pointer isn't advanced
and the volsync record will be read incorrectly in such an instance.

Fix this by always decoding the second status into the second
status/callback block which wasn't being used if the dirs were the same.

The afs_update_dentry_version() calls that update the directory data
version numbers on the dentries can then unconditionally use the second
status record as this will always reflect the state of the destination dir
(the two records will be identical if the destination dir is the same as
the source dir)

Fixes: 260a980317 ("[AFS]: Add "directory write" support.")
Fixes: 30062bd13e ("afs: Implement YFS support in the fs client")
Signed-off-by: David Howells <dhowells@redhat.com>
2020-04-13 15:09:01 +01:00
David Howells
3e0d9892c0 afs: Fix decoding of inline abort codes from version 1 status records
If we're decoding an AFSFetchStatus record and we see that the version is 1
and the abort code is set and we're expecting inline errors, then we store
the abort code and ignore the remaining status record (which is correct),
but we don't set the flag to say we got a valid abort code.

This can affect operation of YFS.RemoveFile2 when removing a file and the
operation of {,Y}FS.InlineBulkStatus when prospectively constructing or
updating of a set of inodes during a lookup.

Fix this to indicate the reception of a valid abort code.

Fixes: a38a75581e ("afs: Fix unlink to handle YFS.RemoveFile2 better")
Signed-off-by: David Howells <dhowells@redhat.com>
2020-04-13 15:09:01 +01:00
David Howells
c72057b56f afs: Fix missing XDR advance in xdr_decode_{AFS,YFS}FSFetchStatus()
If we receive a status record that has VNOVNODE set in the abort field,
xdr_decode_AFSFetchStatus() and xdr_decode_YFSFetchStatus() don't advance
the XDR pointer, thereby corrupting anything subsequent decodes from the
same block of data.

This has the potential to affect AFS.InlineBulkStatus and
YFS.InlineBulkStatus operation, but probably doesn't since the status
records are extracted as individual blocks of data and the buffer pointer
is reset between blocks.

It does affect YFS.RemoveFile2 operation, corrupting the volsync record -
though that is not currently used.

Other operations abort the entire operation rather than returning an error
inline, in which case there is no decoding to be done.

Fix this by unconditionally advancing the xdr pointer.

Fixes: 684b0f68cf ("afs: Fix AFSFetchStatus decoder to provide OpenAFS compatibility")
Signed-off-by: David Howells <dhowells@redhat.com>
2020-04-13 15:09:01 +01:00
David Howells
9efcc4a129 afs: Fix unpinned address list during probing
When it's probing all of a fileserver's interfaces to find which one is
best to use, afs_do_probe_fileserver() takes a lock on the server record
and notes the pointer to the address list.

It doesn't, however, pin the address list, so as soon as it drops the
lock, there's nothing to stop the address list from being freed under
us.

Fix this by taking a ref on the address list inside the locked section
and dropping it at the end of the function.

Fixes: 3bf0fb6f33 ("afs: Probe multiple fileservers simultaneously")
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-03-26 16:04:29 -07:00
Linus Torvalds
1b649e0bca Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from David Miller:

 1) Fix deadlock in bpf_send_signal() from Yonghong Song.

 2) Fix off by one in kTLS offload of mlx5, from Tariq Toukan.

 3) Add missing locking in iwlwifi mvm code, from Avraham Stern.

 4) Fix MSG_WAITALL handling in rxrpc, from David Howells.

 5) Need to hold RTNL mutex in tcindex_partial_destroy_work(), from Cong
    Wang.

 6) Fix producer race condition in AF_PACKET, from Willem de Bruijn.

 7) cls_route removes the wrong filter during change operations, from
    Cong Wang.

 8) Reject unrecognized request flags in ethtool netlink code, from
    Michal Kubecek.

 9) Need to keep MAC in reset until PHY is up in bcmgenet driver, from
    Doug Berger.

10) Don't leak ct zone template in act_ct during replace, from Paul
    Blakey.

11) Fix flushing of offloaded netfilter flowtable flows, also from Paul
    Blakey.

12) Fix throughput drop during tx backpressure in cxgb4, from Rahul
    Lakkireddy.

13) Don't let a non-NULL skb->dev leave the TCP stack, from Eric
    Dumazet.

14) TCP_QUEUE_SEQ socket option has to update tp->copied_seq as well,
    also from Eric Dumazet.

15) Restrict macsec to ethernet devices, from Willem de Bruijn.

16) Fix reference leak in some ethtool *_SET handlers, from Michal
    Kubecek.

17) Fix accidental disabling of MSI for some r8169 chips, from Heiner
    Kallweit.

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (138 commits)
  net: Fix CONFIG_NET_CLS_ACT=n and CONFIG_NFT_FWD_NETDEV={y, m} build
  net: ena: Add PCI shutdown handler to allow safe kexec
  selftests/net/forwarding: define libs as TEST_PROGS_EXTENDED
  selftests/net: add missing tests to Makefile
  r8169: re-enable MSI on RTL8168c
  net: phy: mdio-bcm-unimac: Fix clock handling
  cxgb4/ptp: pass the sign of offset delta in FW CMD
  net: dsa: tag_8021q: replace dsa_8021q_remove_header with __skb_vlan_pop
  net: cbs: Fix software cbs to consider packet sending time
  net/mlx5e: Do not recover from a non-fatal syndrome
  net/mlx5e: Fix ICOSQ recovery flow with Striding RQ
  net/mlx5e: Fix missing reset of SW metadata in Striding RQ reset
  net/mlx5e: Enhance ICOSQ WQE info fields
  net/mlx5_core: Set IB capability mask1 to fix ib_srpt connection failure
  selftests: netfilter: add nfqueue test case
  netfilter: nft_fwd_netdev: allow to redirect to ifb via ingress
  netfilter: nft_fwd_netdev: validate family and chain type
  netfilter: nft_set_rbtree: Detect partial overlaps on insertion
  netfilter: nft_set_rbtree: Introduce and use nft_rbtree_interval_start()
  netfilter: nft_set_pipapo: Separate partial and complete overlap cases on insertion
  ...
2020-03-25 13:58:05 -07:00
David Howells
7d7587db0d afs: Fix client call Rx-phase signal handling
Fix the handling of signals in client rxrpc calls made by the afs
filesystem.  Ignore signals completely, leaving call abandonment or
connection loss to be detected by timeouts inside AF_RXRPC.

Allowing a filesystem call to be interrupted after the entire request has
been transmitted and an abort sent means that the server may or may not
have done the action - and we don't know.  It may even be worse than that
for older servers.

Fixes: bc5e3a546d ("rxrpc: Use MSG_WAITALL to tell sendmsg() to temporarily ignore signals")
Signed-off-by: David Howells <dhowells@redhat.com>
2020-03-13 23:04:35 +00:00
David Howells
dde9f09558 afs: Fix handling of an abort from a service handler
When an AFS service handler function aborts a call, AF_RXRPC marks the call
as complete - which means that it's not going to get any more packets from
the receiver.  This is a problem because reception of the final ACK is what
triggers afs_deliver_to_call() to drop the final ref on the afs_call
object.

Instead, aborted AFS service calls may then just sit around waiting for
ever or until they're displaced by a new call on the same connection
channel or a connection-level abort.

Fix this by calling afs_set_call_complete() to finalise the afs_call struct
representing the call.

However, we then need to drop the ref that stops the call from being
deallocated.  We can do this in afs_set_call_complete(), as the work queue
is holding a separate ref of its own, but then we shouldn't do it in
afs_process_async_call() and afs_delete_async_call().

call->drop_ref is set to indicate that a ref needs dropping for a call and
this is dealt with when we transition a call to AFS_CALL_COMPLETE.

But then we also need to get rid of the ref that pins an asynchronous
client call.  We can do this by the same mechanism, setting call->drop_ref
for an async client call too.

We can also get rid of call->incoming since nothing ever sets it and only
one thing ever checks it (futilely).


A trace of the rxrpc_call and afs_call struct ref counting looks like:

          <idle>-0     [001] ..s5   164.764892: rxrpc_call: c=00000002 SEE u=3 sp=rxrpc_new_incoming_call+0x473/0xb34 a=00000000442095b5
          <idle>-0     [001] .Ns5   164.766001: rxrpc_call: c=00000002 QUE u=4 sp=rxrpc_propose_ACK+0xbe/0x551 a=00000000442095b5
          <idle>-0     [001] .Ns4   164.766005: rxrpc_call: c=00000002 PUT u=3 sp=rxrpc_new_incoming_call+0xa3f/0xb34 a=00000000442095b5
          <idle>-0     [001] .Ns7   164.766433: afs_call: c=00000002 WAKE  u=2 o=11 sp=rxrpc_notify_socket+0x196/0x33c
     kworker/1:2-1810  [001] ...1   164.768409: rxrpc_call: c=00000002 SEE u=3 sp=rxrpc_process_call+0x25/0x7ae a=00000000442095b5
     kworker/1:2-1810  [001] ...1   164.769439: rxrpc_tx_packet: c=00000002 e9f1a7a8:95786a88:00000008:09c5 00000001 00000000 02 22 ACK CallAck
     kworker/1:2-1810  [001] ...1   164.769459: rxrpc_call: c=00000002 PUT u=2 sp=rxrpc_process_call+0x74f/0x7ae a=00000000442095b5
     kworker/1:2-1810  [001] ...1   164.770794: afs_call: c=00000002 QUEUE u=3 o=12 sp=afs_deliver_to_call+0x449/0x72c
     kworker/1:2-1810  [001] ...1   164.770829: afs_call: c=00000002 PUT   u=2 o=12 sp=afs_process_async_call+0xdb/0x11e
     kworker/1:2-1810  [001] ...2   164.771084: rxrpc_abort: c=00000002 95786a88:00000008 s=0 a=1 e=1 K-1
     kworker/1:2-1810  [001] ...1   164.771461: rxrpc_tx_packet: c=00000002 e9f1a7a8:95786a88:00000008:09c5 00000002 00000000 04 00 ABORT CallAbort
     kworker/1:2-1810  [001] ...1   164.771466: afs_call: c=00000002 PUT   u=1 o=12 sp=SRXAFSCB_ProbeUuid+0xc1/0x106

The abort generated in SRXAFSCB_ProbeUuid(), labelled "K-1", indicates that
the local filesystem/cache manager didn't recognise the UUID as its own.

Fixes: 2067b2b3f4 ("afs: Fix the CB.ProbeUuid service handler to reply correctly")
Signed-off-by: David Howells <dhowells@redhat.com>
2020-03-13 23:04:35 +00:00
David Howells
4636cf184d afs: Fix some tracing details
Fix a couple of tracelines to indicate the usage count after the atomic op,
not the usage count before it to be consistent with other afs and rxrpc
trace lines.

Change the wording of the afs_call_trace_work trace ID label from "WORK" to
"QUEUE" to reflect the fact that it's queueing work, not doing work.

Fixes: 341f741f04 ("afs: Refcount the afs_call struct")
Signed-off-by: David Howells <dhowells@redhat.com>
2020-03-13 23:04:34 +00:00
David Howells
e138aa7d32 rxrpc: Fix call interruptibility handling
Fix the interruptibility of kernel-initiated client calls so that they're
either only interruptible when they're waiting for a call slot to come
available or they're not interruptible at all.  Either way, they're not
interruptible during transmission.

This should help prevent StoreData calls from being interrupted when
writeback is in progress.  It doesn't, however, handle interruption during
the receive phase.

Userspace-initiated calls are still interruptable.  After the signal has
been handled, sendmsg() will return the amount of data copied out of the
buffer and userspace can perform another sendmsg() call to continue
transmission.

Fixes: bc5e3a546d ("rxrpc: Use MSG_WAITALL to tell sendmsg() to temporarily ignore signals")
Signed-off-by: David Howells <dhowells@redhat.com>
2020-03-13 23:04:30 +00:00
Jann Horn
ddd2b85ff7 afs: Use kfree_rcu() instead of casting kfree() to rcu_callback_t
afs_put_addrlist() casts kfree() to rcu_callback_t. Apart from being wrong
in theory, this might also blow up when people start enforcing function
types via compiler instrumentation, and it means the rcu_head has to be
first in struct afs_addr_list.

Use kfree_rcu() instead, it's simpler and more correct.

Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-03-13 10:47:33 -07:00
Linus Torvalds
c9d35ee049 Merge branch 'merge.nfs-fs_parse.1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs file system parameter updates from Al Viro:
 "Saner fs_parser.c guts and data structures. The system-wide registry
  of syntax types (string/enum/int32/oct32/.../etc.) is gone and so is
  the horror switch() in fs_parse() that would have to grow another case
  every time something got added to that system-wide registry.

  New syntax types can be added by filesystems easily now, and their
  namespace is that of functions - not of system-wide enum members. IOW,
  they can be shared or kept private and if some turn out to be widely
  useful, we can make them common library helpers, etc., without having
  to do anything whatsoever to fs_parse() itself.

  And we already get that kind of requests - the thing that finally
  pushed me into doing that was "oh, and let's add one for timeouts -
  things like 15s or 2h". If some filesystem really wants that, let them
  do it. Without somebody having to play gatekeeper for the variants
  blessed by direct support in fs_parse(), TYVM.

  Quite a bit of boilerplate is gone. And IMO the data structures make a
  lot more sense now. -200LoC, while we are at it"

* 'merge.nfs-fs_parse.1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (25 commits)
  tmpfs: switch to use of invalfc()
  cgroup1: switch to use of errorfc() et.al.
  procfs: switch to use of invalfc()
  hugetlbfs: switch to use of invalfc()
  cramfs: switch to use of errofc() et.al.
  gfs2: switch to use of errorfc() et.al.
  fuse: switch to use errorfc() et.al.
  ceph: use errorfc() and friends instead of spelling the prefix out
  prefix-handling analogues of errorf() and friends
  turn fs_param_is_... into functions
  fs_parse: handle optional arguments sanely
  fs_parse: fold fs_parameter_desc/fs_parameter_spec
  fs_parser: remove fs_parameter_description name field
  add prefix to fs_context->log
  ceph_parse_param(), ceph_parse_mon_ips(): switch to passing fc_log
  new primitive: __fs_parse()
  switch rbd and libceph to p_log-based primitives
  struct p_log, variants of warnf() et.al. taking that one instead
  teach logfc() to handle prefices, give it saner calling conventions
  get rid of cg_invalf()
  ...
2020-02-08 13:26:41 -08:00
Al Viro
d7167b1499 fs_parse: fold fs_parameter_desc/fs_parameter_spec
The former contains nothing but a pointer to an array of the latter...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-02-07 14:48:37 -05:00
Eric Sandeen
96cafb9ccb fs_parser: remove fs_parameter_description name field
Unused now.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-02-07 14:48:36 -05:00
Al Viro
5eede62529 fold struct fs_parameter_enum into struct constant_table
no real difference now

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-02-07 00:12:50 -05:00
Al Viro
2710c957a8 fs_parse: get rid of ->enums
Don't do a single array; attach them to fsparam_enum() entry
instead.  And don't bother trying to embed the names into those -
it actually loses memory, with no real speedup worth mentioning.

Simplifies validation as well.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-02-07 00:12:50 -05:00
David Howells
a45ea48e2b afs: Fix characters allowed into cell names
The afs filesystem needs to prohibit certain characters from cell names,
such as '/', as these are used to form filenames in procfs, leading to
the following warning being generated:

	WARNING: CPU: 0 PID: 3489 at fs/proc/generic.c:178

Fix afs_alloc_cell() to disallow nonprintable characters, '/', '@' and
names that begin with a dot.

Remove the check for "@cell" as that is then redundant.

This can be tested by running:

	echo add foo/.bar 1.2.3.4 >/proc/fs/afs/cells

Note that we will also need to deal with:

 - Names ending in ".invalid" shouldn't be passed to the DNS.

 - Names that contain non-valid domainname chars shouldn't be passed to
   the DNS.

 - DNS replies that say "your-dns-needs-immediate-attention.<gTLD>" and
   replies containing A records that say 127.0.53.53 should be
   considered invalid.
   [https://www.icann.org/en/system/files/files/name-collision-mitigation-01aug14-en.pdf]

but these need to be dealt with by the kafs-client DNS program rather
than the kernel.

Reported-by: syzbot+b904ba7c947a37b4b291@syzkaller.appspotmail.com
Cc: stable@kernel.org
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-01-26 08:54:04 -08:00
Linus Torvalds
e033e7d4a8 Merge branch 'dhowells' (patches from DavidH)
Merge misc fixes from David Howells.

Two afs fixes and a key refcounting fix.

* dhowells:
  afs: Fix afs_lookup() to not clobber the version on a new dentry
  afs: Fix use-after-loss-of-ref
  keys: Fix request_key() cache
2020-01-14 09:56:31 -08:00
David Howells
f52b83b0b1 afs: Fix afs_lookup() to not clobber the version on a new dentry
Fix afs_lookup() to not clobber the version set on a new dentry by
afs_do_lookup() - especially as it's using the wrong version of the
version (we need to use the one given to us by whatever op the dir
contents correspond to rather than what's in the afs_vnode).

Fixes: 9dd0b82ef5 ("afs: Fix missing dentry data version updating")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-01-14 09:40:06 -08:00
David Howells
40a708bd62 afs: Fix use-after-loss-of-ref
afs_lookup() has a tracepoint to indicate the outcome of
d_splice_alias(), passing it the inode to retrieve the fid from.
However, the function gave up its ref on that inode when it called
d_splice_alias(), which may have failed and dropped the inode.

Fix this by caching the fid.

Fixes: 80548b0399 ("afs: Add more tracepoints")
Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-01-14 09:40:06 -08:00
David Howells
50559800b7 afs: Show volume name in /proc/net/afs/<cell>/volumes
Show the name of each volume in /proc/net/afs/<cell>/volumes to make it
easier to work out the name corresponding to a volume ID.  This makes it
easier to work out which mounts in /proc/mounts correspond to which volume
ID.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Marc Dionne <marc.dionne@auristor.com>
2019-12-11 17:48:20 +00:00
David Howells
106bc79843 afs: Fix missing cell comparison in afs_test_super()
Fix missing cell comparison in afs_test_super().  Without this, any pair
volumes that have the same volume ID will share a superblock, no matter the
cell, unless they're in different network namespaces.

Normally, most users will only deal with a single cell and so they won't
see this.  Even if they do look into a second cell, they won't see a
problem unless they happen to hit a volume with the same ID as one they've
already got mounted.

Before the patch:

    # ls /afs/grand.central.org/archive
    linuxdev/  mailman/  moin/  mysql/  pipermail/  stage/  twiki/
    # ls /afs/kth.se/
    linuxdev/  mailman/  moin/  mysql/  pipermail/  stage/  twiki/
    # cat /proc/mounts | grep afs
    none /afs afs rw,relatime,dyn,autocell 0 0
    #grand.central.org:root.cell /afs/grand.central.org afs ro,relatime 0 0
    #grand.central.org:root.archive /afs/grand.central.org/archive afs ro,relatime 0 0
    #grand.central.org:root.archive /afs/kth.se afs ro,relatime 0 0

After the patch:

    # ls /afs/grand.central.org/archive
    linuxdev/  mailman/  moin/  mysql/  pipermail/  stage/  twiki/
    # ls /afs/kth.se/
    admin/        common/  install/  OldFiles/  service/  system/
    bakrestores/  home/    misc/     pkg/       src/      wsadmin/
    # cat /proc/mounts | grep afs
    none /afs afs rw,relatime,dyn,autocell 0 0
    #grand.central.org:root.cell /afs/grand.central.org afs ro,relatime 0 0
    #grand.central.org:root.archive /afs/grand.central.org/archive afs ro,relatime 0 0
    #kth.se:root.cell /afs/kth.se afs ro,relatime 0 0

Fixes: ^1da177e4c3f4 ("Linux-2.6.12-rc2")
Reported-by: Carsten Jacobi <jacobi@de.ibm.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Marc Dionne <marc.dionne@auristor.com>
Tested-by: Jonathan Billings <jsbillings@jsbillings.org>
cc: Todd DeSantis <atd@us.ibm.com>
2019-12-11 17:47:51 +00:00
David Howells
1da4bd9f9d afs: Fix creation calls in the dynamic root to fail with EOPNOTSUPP
Fix the lookup method on the dynamic root directory such that creation
calls, such as mkdir, open(O_CREAT), symlink, etc. fail with EOPNOTSUPP
rather than failing with some odd error (such as EEXIST).

lookup() itself tries to create automount directories when it is invoked.
These are cached locally in RAM and not committed to storage.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Marc Dionne <marc.dionne@auristor.com>
Tested-by: Jonathan Billings <jsbillings@jsbillings.org>
2019-12-11 17:47:51 +00:00
David Howells
158d583353 afs: Fix mountpoint parsing
Each AFS mountpoint has strings that define the target to be mounted.  This
is required to end in a dot that is supposed to be stripped off.  The
string can include suffixes of ".readonly" or ".backup" - which are
supposed to come before the terminal dot.  To add to the confusion, the "fs
lsmount" afs utility does not show the terminal dot when displaying the
string.

The kernel mount source string parser, however, assumes that the terminal
dot marks the suffix and that the suffix is always "" and is thus ignored.
In most cases, there is no suffix and this is not a problem - but if there
is a suffix, it is lost and this affects the ability to mount the correct
volume.

The command line mount command, on the other hand, is expected not to
include a terminal dot - so the problem doesn't arise there.

Fix this by making sure that the dot exists and then stripping it when
passing the string to the mount configuration.

Fixes: bec5eb6141 ("AFS: Implement an autocell mount capability [ver #2]")
Reported-by: Jonathan Billings <jsbillings@jsbillings.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Marc Dionne <marc.dionne@auristor.com>
Tested-by: Jonathan Billings <jsbillings@jsbillings.org>
2019-12-11 16:56:54 +00:00
David Howells
bcbccaf2ed afs: Fix SELinux setting security label on /afs
Make the AFS dynamic root superblock R/W so that SELinux can set the
security label on it.  Without this, upgrades to, say, the Fedora
filesystem-afs RPM fail if afs is mounted on it because the SELinux label
can't be (re-)applied.

It might be better to make it possible to bypass the R/O check for LSM
label application through setxattr.

Fixes: 4d673da145 ("afs: Support the AFS dynamic root")
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Marc Dionne <marc.dionne@auristor.com>
cc: selinux@vger.kernel.org
cc: linux-security-module@vger.kernel.org
2019-12-09 16:37:36 +00:00
Marc Dionne
9bd0160d12 afs: Fix afs_find_server lookups for ipv4 peers
afs_find_server tries to find a server that has an address that
matches the transport address of an rxrpc peer.  The code assumes
that the transport address is always ipv6, with ipv4 represented
as ipv4 mapped addresses, but that's not the case.  If the transport
family is AF_INET, srx->transport.sin6.sin6_addr.s6_addr32[] will
be beyond the actual ipv4 address and will always be 0, and all
ipv4 addresses will be seen as matching.

As a result, the first ipv4 address seen on any server will be
considered a match, and the server returned may be the wrong one.

One of the consequences is that callbacks received over ipv4 will
only be correctly applied for the server that happens to have the
first ipv4 address on the fs_addresses4 list.  Callbacks over ipv4
from all other servers are dropped, causing the client to serve stale
data.

This is fixed by looking at the transport family, and comparing ipv4
addresses based on a sockaddr_in structure rather than a sockaddr_in6.

Fixes: d2ddc776a4 ("afs: Overhaul volume and server record caching and fileserver rotation")
Signed-off-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2019-12-09 15:04:43 +00:00
Linus Torvalds
4a55d362ff AFS development
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCAAdFiEEqG5UsNXhtOCrfGQP+7dXa6fLC2sFAl3W9UYACgkQ+7dXa6fL
 C2uO1g//T0NvHmrZr6zHbOWlaKkGXRfhgCLENzuTCtcFt29NV+Jv8D/FNuT29d7f
 x8PzrZUBDYfpjP8OSHEivZgU5+a4jpI5pSd2mnGnT3523Oxbm2lIz/SXgpkwQdkM
 4OcK+voCP1MvHbmO7jyOfQm7SX/aOtF90GQrUog5JqwPD0ddSpk/swNNRKZ6xK8/
 cAq9/DHPfYHfLh8wc2FWmhdPA5Px+eKt9kGmMMpwsCulR4yMM7vBCIVNSccSjpYR
 QJzmFpi/TfOiRMc0oZnXLv6UUG+7hHeRfRosoQA8YGGsjwXfs2I7MfAziJx68tfu
 v7beYI+u7tc4EhgK9jXxbgPCJF6nFR/zrbzfC3Zlh7Hr3NCGGzH4gwDu+pn4lwfV
 bpUyA6VwmEt+CVzjj6LB5l4vyRSk+TtVQSwfQvCA7xqvdq0J0/fux6OQ1DwJonQe
 6dOpPUd4ip5tW28S9U7MzbbpMv1kP5hMoAu87gBdygUDhPojM7Ut0mFwZDMOunXg
 vW6oQwKyyFPeJhRcPMKxS7opWQz5889tDe8GPNI/1ociOYCcCkmwZaaG+hYAJ8+N
 8bK2OCi4yNGBa/qMPbwATY+TVKdYcceq/7THxcI3vZk8nVrda73UQHfwUXsjwUzf
 SNNcoMrsEV9BiPSG7gAkCf3VI2gXj+USm3w7SBSjZDM5qR/lRHg=
 =YjAm
 -----END PGP SIGNATURE-----

Merge tag 'afs-next-20191121' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

Pull AFS updates from David Howells:
 "Minor cleanups and fix:

   - Minor fix to make some debugging statements display information
     from the correct iov_iter.

   - Rename some members and variables to make things more obvious or
     consistent.

   - Provide a helper to wrap increments of the usage count on the
     afs_read struct.

   - Use scnprintf() to print into a stack buffer rather than sprintf().

   - Remove some set but unused variables"

* tag 'afs-next-20191121' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
  afs: Remove set but not used variable 'ret'
  afs: Remove set but not used variables 'before', 'after'
  afs: xattr: use scnprintf
  afs: Introduce an afs_get_read() refcount helper
  afs: Rename desc -> req in afs_fetch_data()
  afs: Switch the naming of call->iter and call->_iter
  afs: Use call->_iter not &call->iter in debugging statements
2019-11-30 10:57:22 -08:00
Linus Torvalds
1ae78780ed Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull RCU updates from Ingo Molnar:
 "The main changes in this cycle were:

   - Dynamic tick (nohz) updates, perhaps most notably changes to force
     the tick on when needed due to lengthy in-kernel execution on CPUs
     on which RCU is waiting.

   - Linux-kernel memory consistency model updates.

   - Replace rcu_swap_protected() with rcu_prepace_pointer().

   - Torture-test updates.

   - Documentation updates.

   - Miscellaneous fixes"

* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (51 commits)
  security/safesetid: Replace rcu_swap_protected() with rcu_replace_pointer()
  net/sched: Replace rcu_swap_protected() with rcu_replace_pointer()
  net/netfilter: Replace rcu_swap_protected() with rcu_replace_pointer()
  net/core: Replace rcu_swap_protected() with rcu_replace_pointer()
  bpf/cgroup: Replace rcu_swap_protected() with rcu_replace_pointer()
  fs/afs: Replace rcu_swap_protected() with rcu_replace_pointer()
  drivers/scsi: Replace rcu_swap_protected() with rcu_replace_pointer()
  drm/i915: Replace rcu_swap_protected() with rcu_replace_pointer()
  x86/kvm/pmu: Replace rcu_swap_protected() with rcu_replace_pointer()
  rcu: Upgrade rcu_swap_protected() to rcu_replace_pointer()
  rcu: Suppress levelspread uninitialized messages
  rcu: Fix uninitialized variable in nocb_gp_wait()
  rcu: Update descriptions for rcu_future_grace_period tracepoint
  rcu: Update descriptions for rcu_nocb_wake tracepoint
  rcu: Remove obsolete descriptions for rcu_barrier tracepoint
  rcu: Ensure that ->rcu_urgent_qs is set before resched IPI
  workqueue: Convert for_each_wq to use built-in list check
  rcu: Several rcu_segcblist functions can be static
  rcu: Remove unused function hlist_bl_del_init_rcu()
  Documentation: Rename rcu_node_context_switch() to rcu_note_context_switch()
  ...
2019-11-26 15:42:43 -08:00
Linus Torvalds
436b2a8039 Printk changes for 5.5
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCAAdFiEESH4wyp42V4tXvYsjUqAMR0iAlPIFAl3bpjoACgkQUqAMR0iA
 lPJJDA/+IJT4YCRp2TwV2jvIs0QzvXZrzEsxgCLibLE85mYTJgoQBD3W1bH2eyjp
 T/9U0Zh5PGr/84cHd4qiMxzo+5Olz930weG59NcO4RJBSr671aRYs5tJqwaQAZDR
 wlwaob5S28vUmjPxKulvxv6V3FdI79ZE9xrCOCSTQvz4iCLsGOu+Dn/qtF64pImX
 M/EXzPMBrByiQ8RTM4Ege8JoBqiCZPDG9GR3KPXIXQwEeQgIoeYxwRYakxSmSzz8
 W8NduFCbWavg/yHhghHikMiyOZeQzAt+V9k9WjOBTle3TGJegRhvjgI7508q3tXe
 jQTMGATBOPkIgFaZz7eEn/iBa3jZUIIOzDY93RYBmd26aBvwKLOma/Vkg5oGYl0u
 ZK+CMe+/xXl7brQxQ6JNsQhbSTjT+746LvLJlCvPbbPK9R0HeKNhsdKpGY3ugnmz
 VAnOFIAvWUHO7qx+J+EnOo5iiPpcwXZj4AjrwVrs/x5zVhzwQ+4DSU6rbNn0O1Ak
 ELrBqCQkQzh5kqK93jgMHeWQ9EOUp1Lj6PJhTeVnOx2x8tCOi6iTQFFrfdUPlZ6K
 2DajgrFhti4LvwVsohZlzZuKRm5EuwReLRSOn7PU5qoSm5rcouqMkdlYG/viwyhf
 mTVzEfrfemrIQOqWmzPrWEXlMj2mq8oJm4JkC+jJ/+HsfK4UU8I=
 =QCEy
 -----END PGP SIGNATURE-----

Merge tag 'printk-for-5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk

Pull printk updates from Petr Mladek:

 - Allow to print symbolic error names via new %pe modifier.

 - Use pr_warn() instead of the remaining pr_warning() calls. Fix
   formatting of the related lines.

 - Add VSPRINTF entry to MAINTAINERS.

* tag 'printk-for-5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk: (32 commits)
  checkpatch: don't warn about new vsprintf pointer extension '%pe'
  MAINTAINERS: Add VSPRINTF
  tools lib api: Renaming pr_warning to pr_warn
  ASoC: samsung: Use pr_warn instead of pr_warning
  lib: cpu_rmap: Use pr_warn instead of pr_warning
  trace: Use pr_warn instead of pr_warning
  dma-debug: Use pr_warn instead of pr_warning
  vgacon: Use pr_warn instead of pr_warning
  fs: afs: Use pr_warn instead of pr_warning
  sh/intc: Use pr_warn instead of pr_warning
  scsi: Use pr_warn instead of pr_warning
  platform/x86: intel_oaktrail: Use pr_warn instead of pr_warning
  platform/x86: asus-laptop: Use pr_warn instead of pr_warning
  platform/x86: eeepc-laptop: Use pr_warn instead of pr_warning
  oprofile: Use pr_warn instead of pr_warning
  of: Use pr_warn instead of pr_warning
  macintosh: Use pr_warn instead of pr_warning
  idsn: Use pr_warn instead of pr_warning
  ide: Use pr_warn instead of pr_warning
  crypto: n2: Use pr_warn instead of pr_warning
  ...
2019-11-25 19:40:40 -08:00
Marc Dionne
b485275f1a afs: Fix large file support
By default s_maxbytes is set to MAX_NON_LFS, which limits the usable
file size to 2GB, enforced by the vfs.

Commit b9b1f8d593 ("AFS: write support fixes") added support for the
64-bit fetch and store server operations, but did not change this value.
As a result, attempts to write past the 2G mark result in EFBIG errors:

 $ dd if=/dev/zero of=foo bs=1M count=1 seek=2048
 dd: error writing 'foo': File too large

Set s_maxbytes to MAX_LFS_FILESIZE.

Fixes: b9b1f8d593 ("AFS: write support fixes")
Signed-off-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-11-22 14:19:26 -08:00
Marc Dionne
cd340703c2 afs: Fix possible assert with callbacks from yfs servers
Servers sending callback breaks to the YFS_CM_SERVICE service may
send up to YFSCBMAX (1024) fids in a single RPC.  Anything over
AFSCBMAX (50) will cause the assert in afs_break_callbacks to trigger.

Remove the assert, as the count has already been checked against
the appropriate max values in afs_deliver_cb_callback and
afs_deliver_yfs_cb_callback.

Fixes: 35dbfba311 ("afs: Implement the YFS cache manager service")
Signed-off-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-11-22 14:19:26 -08:00
zhengbin
4fe171bb81 afs: Remove set but not used variable 'ret'
Fixes gcc '-Wunused-but-set-variable' warning:

fs/afs/server.c: In function afs_install_server:
fs/afs/server.c:157:6: warning: variable ret set but not used [-Wunused-but-set-variable]

It is not used since commit d2ddc776a4 ("afs:
Overhaul volume and server record caching and fileserver rotation")

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: zhengbin <zhengbin13@huawei.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2019-11-21 20:36:04 +00:00
zhengbin
51590df4f3 afs: Remove set but not used variables 'before', 'after'
Fixes gcc '-Wunused-but-set-variable' warning:

fs/afs/dir_edit.c: In function afs_set_contig_bits:
fs/afs/dir_edit.c:75:20: warning: variable after set but not used [-Wunused-but-set-variable]
fs/afs/dir_edit.c: In function afs_set_contig_bits:
fs/afs/dir_edit.c:75:12: warning: variable before set but not used [-Wunused-but-set-variable]
fs/afs/dir_edit.c: In function afs_clear_contig_bits:
fs/afs/dir_edit.c💯20: warning: variable after set but not used [-Wunused-but-set-variable]
fs/afs/dir_edit.c: In function afs_clear_contig_bits:
fs/afs/dir_edit.c💯12: warning: variable before set but not used [-Wunused-but-set-variable]

They are never used since commit 63a4681ff3.

Fixes: 63a4681ff3 ("afs: Locally edit directory data for mkdir/create/unlink/...")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: zhengbin <zhengbin13@huawei.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2019-11-21 20:36:00 +00:00
Mark Salyzyn
2e2fae99d1 afs: xattr: use scnprintf
sprintf and snprintf are fragile in future maintenance, switch to
using scnprintf to ensure no accidental Use After Free conditions
are introduced.

Signed-off-by: Mark Salyzyn <salyzyn@android.com>
Cc: linux-kernel@vger.kernel.org
Cc: linux-fsdevel@vger.kernel.org
Cc: David Howells <dhowells@redhat.com>
Cc: linux-afs@lists.infradead.org
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: David Howells <dhowells@redhat.com>
2019-11-21 09:12:17 +00:00
David Howells
d4438a2529 afs: Introduce an afs_get_read() refcount helper
Introduce an afs_get_read() helper to get a reference on an afs_read
object.

Signed-off-by: David Howells <dhowells@redhat.com>
2019-11-21 09:12:17 +00:00
David Howells
0b9c0174d6 afs: Rename desc -> req in afs_fetch_data()
Rename the desc parameter to req in afs_fetch_data() for consistency with
other functions.

Signed-off-by: David Howells <dhowells@redhat.com>
2019-11-21 09:12:17 +00:00
David Howells
fc27612249 afs: Switch the naming of call->iter and call->_iter
Change the name of call->iter to call->def_iter to represent the default
iterator.

Change the name of call->_iter to call->iter to represent the iterator
actually being used.

Signed-off-by: David Howells <dhowells@redhat.com>
2019-11-21 09:12:17 +00:00
David Howells
1b87b025b4 afs: Use call->_iter not &call->iter in debugging statements
Use call->_iter not &call->iter in debugging statements as the latter is a
convenience iter whereas the former represents we're actually doing at the
moment.

Signed-off-by: David Howells <dhowells@redhat.com>
2019-11-21 09:12:16 +00:00
David Howells
c74386d50f afs: Fix missing timeout reset
In afs_wait_for_call_to_complete(), rather than immediately aborting an
operation if a signal occurs, the code attempts to wait for it to
complete, using a schedule timeout of 2*RTT (or min 2 jiffies) and a
check that we're still receiving relevant packets from the server before
we consider aborting the call.  We may even ping the server to check on
the status of the call.

However, there's a missing timeout reset in the event that we do
actually get a packet to process, such that if we then get a couple of
short stalls, we then time out when progress is actually being made.

Fix this by resetting the timeout any time we get something to process.
If it's the failure of the call then the call state will get changed and
we'll exit the loop shortly thereafter.

A symptom of this is data fetches and stores failing with EINTR when
they really shouldn't.

Fixes: bc5e3a546d ("rxrpc: Use MSG_WAITALL to tell sendmsg() to temporarily ignore signals")
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-11-19 14:36:38 -08:00
David Howells
a28f239e29 afs: Fix race in commit bulk status fetch
When a lookup is done, the afs filesystem will perform a bulk status-fetch
operation on the requested vnode (file) plus the next 49 other vnodes from
the directory list (in AFS, directory contents are downloaded as blobs and
parsed locally).  When the results are received, it will speculatively
populate the inode cache from the extra data.

However, if the lookup races with another lookup on the same directory, but
for a different file - one that's in the 49 extra fetches, then if the bulk
status-fetch operation finishes first, it will try and update the inode
from the other lookup.

If this other inode is still in the throes of being created, however, this
will cause an assertion failure in afs_apply_status():

	BUG_ON(test_bit(AFS_VNODE_UNSET, &vnode->flags));

on or about fs/afs/inode.c:175 because it expects data to be there already
that it can compare to.

Fix this by skipping the update if the inode is being created as the
creator will presumably set up the inode with the same information.

Fixes: 39db9815da ("afs: Fix application of the results of a inline bulk status fetch")
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-11-15 10:28:02 -08:00
Paul E. McKenney
62860da708 fs/afs: Replace rcu_swap_protected() with rcu_replace_pointer()
This commit replaces the use of rcu_swap_protected() with the more
intuitively appealing rcu_replace_pointer() as a step towards removing
rcu_swap_protected().

Link: https://lore.kernel.org/lkml/CAHk-=wiAsJLw1egFEE=Z7-GGtM6wcvtyytXZA1+BHqta4gg6Hw@mail.gmail.com/
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
[ paulmck: From rcu_replace() to rcu_replace_pointer() per Ingo Molnar. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Acked-by: David Howells <dhowells@redhat.com>
Cc: <linux-afs@lists.infradead.org>
Cc: <linux-kernel@vger.kernel.org>
2019-10-30 08:44:27 -07:00
Kefeng Wang
a4e530ae7e fs: afs: Use pr_warn instead of pr_warning
As said in commit f2c2cbcc35 ("powerpc: Use pr_warn instead of
pr_warning"), removing pr_warning so all logging messages use a
consistent <prefix>_warn style. Let's do it.

Link: http://lkml.kernel.org/r/20191018031850.48498-23-wangkefeng.wang@huawei.com
To: linux-kernel@vger.kernel.org
Cc: David Howells <dhowells@redhat.com>
Cc: linux-afs@lists.infradead.org
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-10-18 15:01:55 +02:00
Linus Torvalds
1eb80d6ffb Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull more vfs updates from Al Viro:
 "A couple of misc patches"

* 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  afs dynroot: switch to simple_dir_operations
  fs/handle.c - fix up kerneldoc
2019-09-29 19:42:07 -07:00
Al Viro
473ef57ad8 afs dynroot: switch to simple_dir_operations
no point reinventing it (with wrong ->read(), BTW).

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-09-15 12:19:48 -04:00
David Howells
a0753c2900 afs: Support RCU pathwalk
Make afs_permission() and afs_d_revalidate() do initial checks in RCU-mode
pathwalk to reduce latency in pathwalk elements that get done multiple
times.  We don't need to query the server unless we've received a
notification from it that something has changed or the callback has
expired.

This requires that we can request a key and check permits under RCU
conditions if we need to.

Signed-off-by: David Howells <dhowells@redhat.com>
2019-09-02 11:43:54 +01:00
David Howells
8b6a666a97 afs: Provide an RCU-capable key lookup
Provide an RCU-capable key lookup function.  We don't want to call
afs_request_key() in RCU-mode pathwalk as request_key() might sleep, even if
we don't ask it to construct anything as it might find a key that is currently
undergoing construction.

Signed-off-by: David Howells <dhowells@redhat.com>
2019-09-02 11:43:54 +01:00
David Howells
23a289137a afs: Use afs_extract_discard() rather than iov_iter_discard()
Use afs_extract_discard() rather than iov_iter_discard() as the former is a
wrapper for the latter, providing a place to put tracepoints.

Signed-off-by: David Howells <dhowells@redhat.com>
2019-09-02 11:43:54 +01:00
YueHaibing
52c9c13078 afs: remove unused variable 'afs_zero_fid'
fs/afs/fsclient.c:18:29: warning:
 afs_zero_fid defined but not used [-Wunused-const-variable=]

It is never used since commit 025db80c9e ("afs: Trace
the initiation and completion of client calls")

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2019-09-02 11:43:54 +01:00
YueHaibing
cacf2d7dcf afs: remove unused variable 'afs_voltypes'
fs/afs/volume.c:15:26: warning:
 afs_voltypes defined but not used [-Wunused-const-variable=]

It is not used since commit d2ddc776a4 ("afs: Overhaul
volume and server record caching and fileserver rotation")

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2019-09-02 11:43:54 +01:00
YueHaibing
7533be858f afs: use correct afs_call_type in yfs_fs_store_opaque_acl2
It seems that 'yfs_RXYFSStoreOpaqueACL2' should be use in
yfs_fs_store_opaque_acl2().

Fixes: f5e4546347 ("afs: Implement YFS ACL setting")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2019-08-22 13:33:27 +01:00
Marc Dionne
c4c613ff08 afs: Fix possible oops in afs_lookup trace event
The afs_lookup trace event can cause the following:

[  216.576777] BUG: kernel NULL pointer dereference, address: 000000000000023b
[  216.576803] #PF: supervisor read access in kernel mode
[  216.576813] #PF: error_code(0x0000) - not-present page
...
[  216.576913] RIP: 0010:trace_event_raw_event_afs_lookup+0x9e/0x1c0 [kafs]

If the inode from afs_do_lookup() is an error other than ENOENT, or if it
is ENOENT and afs_try_auto_mntpt() returns an error, the trace event will
try to dereference the error pointer as a valid pointer.

Use IS_ERR_OR_NULL to only pass a valid pointer for the trace, or NULL.

Ideally the trace would include the error value, but for now just avoid
the oops.

Fixes: 80548b0399 ("afs: Add more tracepoints")
Signed-off-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2019-08-22 13:33:26 +01:00
David Howells
a5fb8e6c02 afs: Fix leak in afs_lookup_cell_rcu()
Fix a leak on the cell refcount in afs_lookup_cell_rcu() due to
non-clearance of the default error in the case a NULL cell name is passed
and the workstation default cell is used.

Also put a bit at the end to make sure we don't leak a cell ref if we're
going to be returning an error.

This leak results in an assertion like the following when the kafs module is
unloaded:

	AFS: Assertion failed
	2 == 1 is false
	0x2 == 0x1 is false
	------------[ cut here ]------------
	kernel BUG at fs/afs/cell.c:770!
	...
	RIP: 0010:afs_manage_cells+0x220/0x42f [kafs]
	...
	 process_one_work+0x4c2/0x82c
	 ? pool_mayday_timeout+0x1e1/0x1e1
	 ? do_raw_spin_lock+0x134/0x175
	 worker_thread+0x336/0x4a6
	 ? rescuer_thread+0x4af/0x4af
	 kthread+0x1de/0x1ee
	 ? kthread_park+0xd4/0xd4
	 ret_from_fork+0x24/0x30

Fixes: 989782dcdc ("afs: Overhaul cell database management")
Signed-off-by: David Howells <dhowells@redhat.com>
2019-08-22 13:33:26 +01:00
David Howells
9dd0b82ef5 afs: Fix missing dentry data version updating
In the in-kernel afs filesystem, the d_fsdata dentry field is used to hold
the data version of the parent directory when it was created or when
d_revalidate() last caused it to be updated.  This is compared to the
->invalid_before field in the directory inode, rather than the actual data
version number, thereby allowing changes due to local edits to be ignored.
Only if the server data version gets bumped unexpectedly (eg. by a
competing client), do we need to revalidate stuff.

However, the d_fsdata field should also be updated if an rpc op is
performed that modifies that particular dentry.  Such ops return the
revised data version of the directory(ies) involved, so we should use that.

This is particularly problematic for rename, since a dentry from one
directory may be moved directly into another directory (ie. mv a/x b/x).
It would then be sporting the wrong data version - and if this is in the
future, for the destination directory, revalidations would be missed,
leading to foreign renames and hard-link deletion being missed.

Fix this by the following means:

 (1) Return the data version number from operations that read the directory
     contents - if they issue the read.  This starts in afs_dir_iterate()
     and is used, ignored or passed back by its callers.

 (2) In afs_lookup*(), set the dentry version to the version returned by
     (1) before d_splice_alias() is called and the dentry published.

 (3) In afs_d_revalidate(), set the dentry version to that returned from
     (1) if an rpc call was issued.  This means that if a parallel
     procedure, such as mkdir(), modifies the directory, we won't
     accidentally use the data version from that.

 (4) In afs_{mkdir,create,link,symlink}(), set the new dentry's version to
     the directory data version before d_instantiate() is called.

 (5) In afs_{rmdir,unlink}, update the target dentry's version to the
     directory data version as soon as we've updated the directory inode.

 (6) In afs_rename(), we need to unhash the old dentry before we start so
     that we don't get afs_d_revalidate() reverting the version change in
     cross-directory renames.

     We then need to set both the old and the new dentry versions the data
     version of the new directory before we call d_move() as d_move() will
     rehash them.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: David Howells <dhowells@redhat.com>
2019-07-30 14:38:52 +01:00
David Howells
5dc84855b0 afs: Only update d_fsdata if different in afs_d_revalidate()
In the in-kernel afs filesystem, d_fsdata is set with the data version of
the parent directory.  afs_d_revalidate() will update this to the current
directory version, but it shouldn't do this if it the value it read from
d_fsdata is the same as no lock is held and cmpxchg() is not used.

Fix the code to only change the value if it is different from the current
directory version.

Fixes: 260a980317 ("[AFS]: Add "directory write" support.")
Signed-off-by: David Howells <dhowells@redhat.com>
2019-07-30 14:38:51 +01:00
David Howells
37c0bbb332 afs: Fix off-by-one in afs_rename() expected data version calculation
When afs_rename() calculates the expected data version of the target
directory in a cross-directory rename, it doesn't increment it as it
should, so it always thinks that the target inode is unexpectedly modified
on the server.

Fixes: a58823ac45 ("afs: Fix application of status and callback to be under same lock")
Signed-off-by: David Howells <dhowells@redhat.com>
2019-07-30 14:38:51 +01:00
Jia-Ju Bai
a6eed4ab5d fs: afs: Fix a possible null-pointer dereference in afs_put_read()
In afs_read_dir(), there is an if statement on line 255 to check whether
req->pages is NULL:
	if (!req->pages)
		goto error;

If req->pages is NULL, afs_put_read() on line 337 is executed.
In afs_put_read(), req->pages[i] is used on line 195.
Thus, a possible null-pointer dereference may occur in this case.

To fix this possible bug, an if statement is added in afs_put_read() to
check req->pages.

This bug is found by a static analysis tool STCheck written by us.

Fixes: f3ddee8dc4 ("afs: Fix directory handling")
Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2019-07-30 14:38:51 +01:00
Marc Dionne
4a46fdba44 afs: Fix loop index mixup in afs_deliver_vl_get_entry_by_name_u()
afs_deliver_vl_get_entry_by_name_u() scans through the vl entry
received from the volume location server and builds a return list
containing the sites that are currently valid.  When assigning
values for the return list, the index into the vl entry (i) is used
rather than the one for the new list (entry->nr_server).  If all
sites are usable, this works out fine as the indices will match.
If some sites are not valid, for example if AFS_VLSF_DONTUSE is
set, fs_mask and the uuid will be set for the wrong return site.

Fix this by using entry->nr_server as the index into the arrays
being filled in rather than i.

This can lead to EDESTADDRREQ errors if none of the returned sites
have a valid fs_mask.

Fixes: d2ddc776a4 ("afs: Overhaul volume and server record caching and fileserver rotation")
Signed-off-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeffrey Altman <jaltman@auristor.com>
2019-07-30 14:38:51 +01:00
David Howells
2067b2b3f4 afs: Fix the CB.ProbeUuid service handler to reply correctly
Fix the service handler function for the CB.ProbeUuid RPC call so that it
replies in the correct manner - that is an empty reply for success and an
abort of 1 for failure.

Putting 0 or 1 in an integer in the body of the reply should result in the
fileserver throwing an RX_PROTOCOL_ERROR abort and discarding its record of
the client; older servers, however, don't necessarily check that all the
data got consumed, and so might incorrectly think that they got a positive
response and associate the client with the wrong host record.

If the client is incorrectly associated, this will result in callbacks
intended for a different client being delivered to this one and then, when
the other client connects and responds positively, all of the callback
promises meant for the client that issued the improper response will be
lost and it won't receive any further change notifications.

Fixes: 9396d496d7 ("afs: support the CB.ProbeUuid RPC op")
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeffrey Altman <jaltman@auristor.com>
2019-07-30 14:38:51 +01:00
Gustavo A. R. Silva
2988160827 afs: fsclient: Mark expected switch fall-throughs
In preparation to enabling -Wimplicit-fallthrough, mark switch
cases where we are expecting to fall through.

This patch fixes the following warnings:

Warning level 3 was used: -Wimplicit-fallthrough=3

fs/afs/fsclient.c: In function ‘afs_deliver_fs_fetch_acl’:
fs/afs/fsclient.c:2199:19: warning: this statement may fall through [-Wimplicit-fallthrough=]
   call->unmarshall++;
   ~~~~~~~~~~~~~~~~^~
fs/afs/fsclient.c:2202:2: note: here
  case 1:
  ^~~~
fs/afs/fsclient.c:2216:19: warning: this statement may fall through [-Wimplicit-fallthrough=]
   call->unmarshall++;
   ~~~~~~~~~~~~~~~~^~
fs/afs/fsclient.c:2219:2: note: here
  case 2:
  ^~~~
fs/afs/fsclient.c:2225:19: warning: this statement may fall through [-Wimplicit-fallthrough=]
   call->unmarshall++;
   ~~~~~~~~~~~~~~~~^~
fs/afs/fsclient.c:2228:2: note: here
  case 3:
  ^~~~

This patch is part of the ongoing efforts to enable
-Wimplicit-fallthrough.

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
2019-07-25 20:09:49 -05:00
Gustavo A. R. Silva
35a3a90cc5 afs: yfsclient: Mark expected switch fall-throughs
In preparation to enabling -Wimplicit-fallthrough, mark switch
cases where we are expecting to fall through.

This patch fixes the following warnings:

fs/afs/yfsclient.c: In function ‘yfs_deliver_fs_fetch_opaque_acl’:
fs/afs/yfsclient.c:1984:19: warning: this statement may fall through [-Wimplicit-fallthrough=]
   call->unmarshall++;
   ~~~~~~~~~~~~~~~~^~
fs/afs/yfsclient.c:1987:2: note: here
  case 1:
  ^~~~
fs/afs/yfsclient.c:2005:19: warning: this statement may fall through [-Wimplicit-fallthrough=]
   call->unmarshall++;
   ~~~~~~~~~~~~~~~~^~
fs/afs/yfsclient.c:2008:2: note: here
  case 2:
  ^~~~
fs/afs/yfsclient.c:2014:19: warning: this statement may fall through [-Wimplicit-fallthrough=]
   call->unmarshall++;
   ~~~~~~~~~~~~~~~~^~
fs/afs/yfsclient.c:2017:2: note: here
  case 3:
  ^~~~
fs/afs/yfsclient.c:2035:19: warning: this statement may fall through [-Wimplicit-fallthrough=]
   call->unmarshall++;
   ~~~~~~~~~~~~~~~~^~
fs/afs/yfsclient.c:2038:2: note: here
  case 4:
  ^~~~
fs/afs/yfsclient.c:2047:19: warning: this statement may fall through [-Wimplicit-fallthrough=]
   call->unmarshall++;
   ~~~~~~~~~~~~~~~~^~
fs/afs/yfsclient.c:2050:2: note: here
  case 5:
  ^~~~

Warning level 3 was used: -Wimplicit-fallthrough=3

Also, fix some commenting style issues.

This patch is part of the ongoing efforts to enable
-Wimplicit-fallthrough.

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
2019-07-25 20:09:46 -05:00
Linus Torvalds
237f83dfbe Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:
 "Some highlights from this development cycle:

   1) Big refactoring of ipv6 route and neigh handling to support
      nexthop objects configurable as units from userspace. From David
      Ahern.

   2) Convert explored_states in BPF verifier into a hash table,
      significantly decreased state held for programs with bpf2bpf
      calls, from Alexei Starovoitov.

   3) Implement bpf_send_signal() helper, from Yonghong Song.

   4) Various classifier enhancements to mvpp2 driver, from Maxime
      Chevallier.

   5) Add aRFS support to hns3 driver, from Jian Shen.

   6) Fix use after free in inet frags by allocating fqdirs dynamically
      and reworking how rhashtable dismantle occurs, from Eric Dumazet.

   7) Add act_ctinfo packet classifier action, from Kevin
      Darbyshire-Bryant.

   8) Add TFO key backup infrastructure, from Jason Baron.

   9) Remove several old and unused ISDN drivers, from Arnd Bergmann.

  10) Add devlink notifications for flash update status to mlxsw driver,
      from Jiri Pirko.

  11) Lots of kTLS offload infrastructure fixes, from Jakub Kicinski.

  12) Add support for mv88e6250 DSA chips, from Rasmus Villemoes.

  13) Various enhancements to ipv6 flow label handling, from Eric
      Dumazet and Willem de Bruijn.

  14) Support TLS offload in nfp driver, from Jakub Kicinski, Dirk van
      der Merwe, and others.

  15) Various improvements to axienet driver including converting it to
      phylink, from Robert Hancock.

  16) Add PTP support to sja1105 DSA driver, from Vladimir Oltean.

  17) Add mqprio qdisc offload support to dpaa2-eth, from Ioana
      Radulescu.

  18) Add devlink health reporting to mlx5, from Moshe Shemesh.

  19) Convert stmmac over to phylink, from Jose Abreu.

  20) Add PTP PHC (Physical Hardware Clock) support to mlxsw, from
      Shalom Toledo.

  21) Add nftables SYNPROXY support, from Fernando Fernandez Mancera.

  22) Convert tcp_fastopen over to use SipHash, from Ard Biesheuvel.

  23) Track spill/fill of constants in BPF verifier, from Alexei
      Starovoitov.

  24) Support bounded loops in BPF, from Alexei Starovoitov.

  25) Various page_pool API fixes and improvements, from Jesper Dangaard
      Brouer.

  26) Just like ipv4, support ref-countless ipv6 route handling. From
      Wei Wang.

  27) Support VLAN offloading in aquantia driver, from Igor Russkikh.

  28) Add AF_XDP zero-copy support to mlx5, from Maxim Mikityanskiy.

  29) Add flower GRE encap/decap support to nfp driver, from Pieter
      Jansen van Vuuren.

  30) Protect against stack overflow when using act_mirred, from John
      Hurley.

  31) Allow devmap map lookups from eBPF, from Toke Høiland-Jørgensen.

  32) Use page_pool API in netsec driver, Ilias Apalodimas.

  33) Add Google gve network driver, from Catherine Sullivan.

  34) More indirect call avoidance, from Paolo Abeni.

  35) Add kTLS TX HW offload support to mlx5, from Tariq Toukan.

  36) Add XDP_REDIRECT support to bnxt_en, from Andy Gospodarek.

  37) Add MPLS manipulation actions to TC, from John Hurley.

  38) Add sending a packet to connection tracking from TC actions, and
      then allow flower classifier matching on conntrack state. From
      Paul Blakey.

  39) Netfilter hw offload support, from Pablo Neira Ayuso"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (2080 commits)
  net/mlx5e: Return in default case statement in tx_post_resync_params
  mlx5: Return -EINVAL when WARN_ON_ONCE triggers in mlx5e_tls_resync().
  net: dsa: add support for BRIDGE_MROUTER attribute
  pkt_sched: Include const.h
  net: netsec: remove static declaration for netsec_set_tx_de()
  net: netsec: remove superfluous if statement
  netfilter: nf_tables: add hardware offload support
  net: flow_offload: rename tc_cls_flower_offload to flow_cls_offload
  net: flow_offload: add flow_block_cb_is_busy() and use it
  net: sched: remove tcf block API
  drivers: net: use flow block API
  net: sched: use flow block API
  net: flow_offload: add flow_block_cb_{priv, incref, decref}()
  net: flow_offload: add list handling functions
  net: flow_offload: add flow_block_cb_alloc() and flow_block_cb_free()
  net: flow_offload: rename TCF_BLOCK_BINDER_TYPE_* to FLOW_BLOCK_BINDER_TYPE_*
  net: flow_offload: rename TC_BLOCK_{UN}BIND to FLOW_BLOCK_{UN}BIND
  net: flow_offload: add flow_block_cb_setup_simple()
  net: hisilicon: Add an tx_desc to adapt HI13X1_GMAC
  net: hisilicon: Add an rx_desc to adapt HI13X1_GMAC
  ...
2019-07-11 10:55:49 -07:00
Linus Torvalds
8dda9957e3 AFS development
-----BEGIN PGP SIGNATURE-----
 
 iQIVAwUAXRyW8vu3V2unywtrAQIhsw//cVtxLx4ZCox5Z/93cdqych8RoCrwcUEG
 Cli0NAjlp/0HETvCsIqdkPKf+4OYCW1tHB2KTdbFdQLZptLgoEhykx89k70z9ggb
 ViieEa1GvAKhdamVqkPUC+3Q33uzyRaK7Gi5N3phJoaO+o328SlrPG0LerQgY0Np
 Rf3je56A1gIjEgWTmpStxiY262jlgaR3IuvpOqbu2G0TQVWV8CsBKw61fTdmEEQp
 dIkNO/xFXS+PvPdmQe5zCAjD/W2D+ggeBMbBwHF411qA60plGinubBYKZ98ikliZ
 OnQQPExI7mroIMzpYT+rzEQyxui2nz5t+Hj+d6t7iIvitNcX/Q53sVTq3RfQ0FjG
 QCd+j/l2p7fkXK4Sxgb/UBkj/pRr6W+FYSbQ/tmpD8UypEf5B3ln6GuA6yTMuNRF
 wVb744slKWq0c7KUuXmz806B2qJoyFG206jyFnoByvs6cPmB1+JqhBBYOKHcwjbo
 HIK+oUKkEfE6ofjQ3B9xOQ1anfbRnjjfJCmXvns9v57y/nRP2P78HUJNnEsOolk2
 nc3Ep41OgeZdwkts9KnSjmwy6VF3UZ2NQEiWXsUIOxGMtcodw9ci1bpquJ71oyut
 4sFMJvMU4eJD+XuCOlAgpbTaQ0Wuf11kFpl1Cof4fj0Z09C25Ahj6iKEKnumtO+4
 edfNLlwO6oo=
 =wgib
 -----END PGP SIGNATURE-----

Merge tag 'afs-next-20190628' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

Pull afs updates from David Howells:
 "A set of minor changes for AFS:

   - Remove an unnecessary check in afs_unlink()

   - Add a tracepoint for tracking callback management

   - Add a tracepoint for afs_server object usage

   - Use struct_size()

   - Add mappings for AFS UAE abort codes to Linux error codes, using
     symbolic names rather than hex numbers in the .c file"

* tag 'afs-next-20190628' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
  afs: Add support for the UAE error table
  fs/afs: use struct_size() in kzalloc()
  afs: Trace afs_server usage
  afs: Add some callback management tracepoints
  afs: afs_unlink() doesn't need to check dentry->d_inode
2019-07-10 20:55:33 -07:00
Linus Torvalds
e6983afd92 \n
-----BEGIN PGP SIGNATURE-----
 
 iQEzBAABCAAdFiEEq1nRK9aeMoq1VSgcnJ2qBz9kQNkFAl0kWgwACgkQnJ2qBz9k
 QNkkdggA7bdy6xZRPdumZMxtASGDs1JJ4diNs+apgyc6wUfsT1lCE2ap20EdzfzK
 drAvlJt1vYEW+6apOzUXJ0qWXMVRzy4XRl+jVMO9GW6BoY4OyJQ86AQZlEv1zZ4n
 vxeYnlbxA7JyfkWgup0ZSb5EKRSO1eSxZKEZou0wu2jRCRr/E5RyjPQHXaiE5ihc
 7ilEtTI3Qg3nnAK30F0Iy0X3lGqgXj+rlJ0TgR8BBEDllct2wV16vvMl/Sy+BXip
 5sSWjSy8zntMnkSN8yH/oJN0D+fqmCsnYafwqTpPek8izvEz4xpjshbWTDnPm0HM
 eiMC1U3ZJoD3Z4/wxRZ91m60VYgJBA==
 =SVKR
 -----END PGP SIGNATURE-----

Merge tag 'fsnotify_for_v5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs

Pull fsnotify updates from Jan Kara:
 "This contains cleanups of the fsnotify name removal hook and also a
  patch to disable fanotify permission events for 'proc' filesystem"

* tag 'fsnotify_for_v5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
  fsnotify: get rid of fsnotify_nameremove()
  fsnotify: move fsnotify_nameremove() hook out of d_delete()
  configfs: call fsnotify_rmdir() hook
  debugfs: call fsnotify_{unlink,rmdir}() hooks
  debugfs: simplify __debugfs_remove_file()
  devpts: call fsnotify_unlink() hook
  tracefs: call fsnotify_{unlink,rmdir}() hooks
  rpc_pipefs: call fsnotify_{unlink,rmdir}() hooks
  btrfs: call fsnotify_rmdir() hook
  fsnotify: add empty fsnotify_{unlink,rmdir}() hooks
  fanotify: Disallow permission events for proc filesystem
2019-07-10 20:09:17 -07:00
Linus Torvalds
028db3e290 Revert "Merge tag 'keys-acl-20190703' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs"
This reverts merge 0f75ef6a9c (and thus
effectively commits

   7a1ade8475 ("keys: Provide KEYCTL_GRANT_PERMISSION")
   2e12256b9a ("keys: Replace uid/gid/perm permissions checking with an ACL")

that the merge brought in).

It turns out that it breaks booting with an encrypted volume, and Eric
biggers reports that it also breaks the fscrypt tests [1] and loading of
in-kernel X.509 certificates [2].

The root cause of all the breakage is likely the same, but David Howells
is off email so rather than try to work it out it's getting reverted in
order to not impact the rest of the merge window.

 [1] https://lore.kernel.org/lkml/20190710011559.GA7973@sol.localdomain/
 [2] https://lore.kernel.org/lkml/20190710013225.GB7973@sol.localdomain/

Link: https://lore.kernel.org/lkml/CAHk-=wjxoeMJfeBahnWH=9zShKp2bsVy527vo3_y8HfOdhwAAw@mail.gmail.com/
Reported-by: Eric Biggers <ebiggers@kernel.org>
Cc: David Howells <dhowells@redhat.com>
Cc: James Morris <jmorris@namei.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-07-10 18:43:43 -07:00
Linus Torvalds
0f75ef6a9c Keyrings ACL
-----BEGIN PGP SIGNATURE-----
 
 iQIVAwUAXRyyVvu3V2unywtrAQL3xQ//eifjlELkRAPm2EReWwwahdM+9QL/0bAy
 e8eAzP9EaphQGUhpIzM9Y7Cx+a8XW2xACljY8hEFGyxXhDMoLa35oSoJOeay6vQt
 QcgWnDYsET8Z7HOsFCP3ZQqlbbqfsB6CbIKtZoEkZ8ib7eXpYcy1qTydu7wqrl4A
 AaJalAhlUKKUx9hkGGJTh2xvgmxgSJkxx3cNEWJQ2uGgY/ustBpqqT4iwFDsgA/q
 fcYTQFfNQBsC8/SmvQgxJSc+reUdQdp0z1vd8qjpSdFFcTq1qOtK0qDdz1Bbyl24
 hAxvNM1KKav83C8aF7oHhEwLrkD+XiYKixdEiCJJp+A2i+vy2v8JnfgtFTpTgLNK
 5xu2VmaiWmee9SLCiDIBKE4Ghtkr8DQ/5cKFCwthT8GXgQUtdsdwAaT3bWdCNfRm
 DqgU/AyyXhoHXrUM25tPeF3hZuDn2yy6b1TbKA9GCpu5TtznZIHju40Px/XMIpQH
 8d6s/pg+u/SnkhjYWaTvTcvsQ2FB/vZY/UzAVyosnoMBkVfL4UtAHGbb8FBVj1nf
 Dv5VjSjl4vFjgOr3jygEAeD2cJ7L6jyKbtC/jo4dnOmPrSRShIjvfSU04L3z7FZS
 XFjMmGb2Jj8a7vAGFmsJdwmIXZ1uoTwX56DbpNL88eCgZWFPGKU7TisdIWAmJj8U
 N9wholjHJgw=
 =E3bF
 -----END PGP SIGNATURE-----

Merge tag 'keys-acl-20190703' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

Pull keyring ACL support from David Howells:
 "This changes the permissions model used by keys and keyrings to be
  based on an internal ACL by the following means:

   - Replace the permissions mask internally with an ACL that contains a
     list of ACEs, each with a specific subject with a permissions mask.
     Potted default ACLs are available for new keys and keyrings.

     ACE subjects can be macroised to indicate the UID and GID specified
     on the key (which remain). Future commits will be able to add
     additional subject types, such as specific UIDs or domain
     tags/namespaces.

     Also split a number of permissions to give finer control. Examples
     include splitting the revocation permit from the change-attributes
     permit, thereby allowing someone to be granted permission to revoke
     a key without allowing them to change the owner; also the ability
     to join a keyring is split from the ability to link to it, thereby
     stopping a process accessing a keyring by joining it and thus
     acquiring use of possessor permits.

   - Provide a keyctl to allow the granting or denial of one or more
     permits to a specific subject. Direct access to the ACL is not
     granted, and the ACL cannot be viewed"

* tag 'keys-acl-20190703' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
  keys: Provide KEYCTL_GRANT_PERMISSION
  keys: Replace uid/gid/perm permissions checking with an ACL
2019-07-08 19:56:57 -07:00
Linus Torvalds
c84ca912b0 Keyrings namespacing
-----BEGIN PGP SIGNATURE-----
 
 iQIVAwUAXRU89Pu3V2unywtrAQIdBBAAmMBsrfv+LUN4Vru/D6KdUO4zdYGcNK6m
 S56bcNfP6oIDEj6HrNNnzKkWIZpdZ61Odv1zle96+v4WZ/6rnLCTpcsdaFNTzaoO
 YT2jk7jplss0ImrMv1DSoykGqO3f0ThMIpGCxHKZADGSu0HMbjSEh+zLPV4BaMtT
 BVuF7P3eZtDRLdDtMtYcgvf5UlbdoBEY8w1FUjReQx8hKGxVopGmCo5vAeiY8W9S
 ybFSZhPS5ka33ynVrLJH2dqDo5A8pDhY8I4bdlcxmNtRhnPCYZnuvTqeAzyUKKdI
 YN9zJeDu1yHs9mi8dp45NPJiKy6xLzWmUwqH8AvR8MWEkrwzqbzNZCEHZ41j74hO
 YZWI0JXi72cboszFvOwqJERvITKxrQQyVQLPRQE2vVbG0bIZPl8i7oslFVhitsl+
 evWqHb4lXY91rI9cC6JIXR1OiUjp68zXPv7DAnxv08O+PGcioU1IeOvPivx8QSx4
 5aUeCkYIIAti/GISzv7xvcYh8mfO76kBjZSB35fX+R9DkeQpxsHmmpWe+UCykzWn
 EwhHQn86+VeBFP6RAXp8CgNCLbrwkEhjzXQl/70s1eYbwvK81VcpDAQ6+cjpf4Hb
 QUmrUJ9iE0wCNl7oqvJZoJvWVGlArvPmzpkTJk3N070X2R0T7x1WCsMlPDMJGhQ2
 fVHvA3QdgWs=
 =Push
 -----END PGP SIGNATURE-----

Merge tag 'keys-namespace-20190627' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

Pull keyring namespacing from David Howells:
 "These patches help make keys and keyrings more namespace aware.

  Firstly some miscellaneous patches to make the process easier:

   - Simplify key index_key handling so that the word-sized chunks
     assoc_array requires don't have to be shifted about, making it
     easier to add more bits into the key.

   - Cache the hash value in the key so that we don't have to calculate
     on every key we examine during a search (it involves a bunch of
     multiplications).

   - Allow keying_search() to search non-recursively.

  Then the main patches:

   - Make it so that keyring names are per-user_namespace from the point
     of view of KEYCTL_JOIN_SESSION_KEYRING so that they're not
     accessible cross-user_namespace.

     keyctl_capabilities() shows KEYCTL_CAPS1_NS_KEYRING_NAME for this.

   - Move the user and user-session keyrings to the user_namespace
     rather than the user_struct. This prevents them propagating
     directly across user_namespaces boundaries (ie. the KEY_SPEC_*
     flags will only pick from the current user_namespace).

   - Make it possible to include the target namespace in which the key
     shall operate in the index_key. This will allow the possibility of
     multiple keys with the same description, but different target
     domains to be held in the same keyring.

     keyctl_capabilities() shows KEYCTL_CAPS1_NS_KEY_TAG for this.

   - Make it so that keys are implicitly invalidated by removal of a
     domain tag, causing them to be garbage collected.

   - Institute a network namespace domain tag that allows keys to be
     differentiated by the network namespace in which they operate. New
     keys that are of a type marked 'KEY_TYPE_NET_DOMAIN' are assigned
     the network domain in force when they are created.

   - Make it so that the desired network namespace can be handed down
     into the request_key() mechanism. This allows AFS, NFS, etc. to
     request keys specific to the network namespace of the superblock.

     This also means that the keys in the DNS record cache are
     thenceforth namespaced, provided network filesystems pass the
     appropriate network namespace down into dns_query().

     For DNS, AFS and NFS are good, whilst CIFS and Ceph are not. Other
     cache keyrings, such as idmapper keyrings, also need to set the
     domain tag - for which they need access to the network namespace of
     the superblock"

* tag 'keys-namespace-20190627' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
  keys: Pass the network namespace into request_key mechanism
  keys: Network namespace domain tag
  keys: Garbage collect keys for which the domain has been removed
  keys: Include target namespace in match criteria
  keys: Move the user and user-session keyrings to the user_namespace
  keys: Namespace keyring names
  keys: Add a 'recurse' flag for keyring searches
  keys: Cache the hash value to avoid lots of recalculation
  keys: Simplify key description management
2019-07-08 19:36:47 -07:00
David Howells
1eda8bab70 afs: Add support for the UAE error table
Add support for mapping AFS UAE abort codes to Linux errno values.

Signed-off-by: David Howells <dhowells@redhat.com>
2019-06-28 18:37:53 +01:00
David S. Miller
d96ff269a0 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
The new route handling in ip_mc_finish_output() from 'net' overlapped
with the new support for returning congestion notifications from BPF
programs.

In order to handle this I had to take the dev_loopback_xmit() calls
out of the switch statement.

The aquantia driver conflicts were simple overlapping changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-27 21:06:39 -07:00
Linus Torvalds
cd0f3aaebc AFS fixes
-----BEGIN PGP SIGNATURE-----
 
 iQIVAwUAXRMn5vu3V2unywtrAQICpA/+IIINk6MJVQDzGhOnvWrbGdPnOdJEUyLN
 B9U4bLZJRg/j+Sqodn+fXIfsEO4FQflkSJD+xoBi4pzBZcr0xkLUVOog/1S7dv4J
 bPVT9p2f3ITNiatmisOrUe1InuHa6Wb/cUnQaLLRhd7NqbawKGRQG4tv4CGwKn67
 dJIOOm/iTCs1ACES4C5QOpU7/DWK38Pn3BbnN21bFzDgfbtbdDTaFFkhFtXy78oB
 Gcj5g+ULpkKBcuJThFuJUPZ9E4qICNZR4kJXEULSvykDDRzluhJmQ+v8btm6NJsq
 hMqTrT9M2y114V1OqXj3me7tA6wOEAfTQ0WzpzF2SmyFQKnSly/EkWc4HZXFD/8O
 BczCcABUbuKNE/pJSELx6k1M0+00QfeLcjHPc6joZFCni3lMdYWOncn/syyHw5P+
 rc9JQsy3+dLcFsaVQ5eGmX6NDc70dCrAlS6MllIzSBcwAVCctTKwm0meaSW6B2y6
 VymPy+cqi1RxMKyiQ0hAeU7Xe6yqFcl6rtonfCQqRLxkfzrCXkDp6/ELOXBzDft1
 ey6+N3WsmWW7YSPuM/SIZKV66rshlflj0w+FRluZEEAF1NYeYqXUDvK/S8KC9kPG
 AXUDvhI+tBpxg1AVz94JN714VmkbY23xV0g44eQsdqSQm2YvsxiFCSWZZ6L/KEWe
 kWQc6BGDCB0=
 =YTdG
 -----END PGP SIGNATURE-----

Merge tag 'afs-fixes-20190620' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

Pull AFS fixes from David Howells:
 "The in-kernel AFS client has been undergoing testing on opendev.org on
  one of their mirror machines. They are using AFS to hold data that is
  then served via apache, and Ian Wienand had reported seeing oopses,
  spontaneous machine reboots and updates to volumes going missing. This
  patch series appears to have fixed the problem, very probably due to
  patch (2), but it's not 100% certain.

  (1) Fix the printing of the "vnode modified" warning to exclude checks
      on files for which we don't have a callback promise from the
      server (and so don't expect the server to tell us when it
      changes).

      Without this, for every file or directory for which we still have
      an in-core inode that gets changed on the server, we may get a
      message logged when we next look at it. This can happen in bulk
      if, for instance, someone does "vos release" to update a R/O
      volume from a R/W volume and a whole set of files are all changed
      together.

      We only really want to log a message if the file changed and the
      server didn't tell us about it or we failed to track the state
      internally.

  (2) Fix accidental corruption of either afs_vlserver struct objects or
      the the following memory locations (which could hold anything).
      The issue is caused by a union that points to two different
      structs in struct afs_call (to save space in the struct). The call
      cleanup code assumes that it can simply call the cleanup for one
      of those structs if not NULL - when it might be actually pointing
      to the other struct.

      This means that every Volume Location RPC op is going to corrupt
      something.

  (3) Fix an uninitialised spinlock. This isn't too bad, it just causes
      a one-off warning if lockdep is enabled when "vos release" is
      called, but the spinlock still behaves correctly.

  (4) Fix the setting of i_block in the inode. This causes du, for
      example, to produce incorrect results, but otherwise should not be
      dangerous to the kernel"

* tag 'afs-fixes-20190620' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
  afs: Fix setting of i_blocks
  afs: Fix uninitialised spinlock afs_volume::cb_break_lock
  afs: Fix vlserver record corruption
  afs: Fix over zealous "vnode modified" warnings
2019-06-28 08:34:12 +08:00
David Howells
2e12256b9a keys: Replace uid/gid/perm permissions checking with an ACL
Replace the uid/gid/perm permissions checking on a key with an ACL to allow
the SETATTR and SEARCH permissions to be split.  This will also allow a
greater range of subjects to represented.

============
WHY DO THIS?
============

The problem is that SETATTR and SEARCH cover a slew of actions, not all of
which should be grouped together.

For SETATTR, this includes actions that are about controlling access to a
key:

 (1) Changing a key's ownership.

 (2) Changing a key's security information.

 (3) Setting a keyring's restriction.

And actions that are about managing a key's lifetime:

 (4) Setting an expiry time.

 (5) Revoking a key.

and (proposed) managing a key as part of a cache:

 (6) Invalidating a key.

Managing a key's lifetime doesn't really have anything to do with
controlling access to that key.

Expiry time is awkward since it's more about the lifetime of the content
and so, in some ways goes better with WRITE permission.  It can, however,
be set unconditionally by a process with an appropriate authorisation token
for instantiating a key, and can also be set by the key type driver when a
key is instantiated, so lumping it with the access-controlling actions is
probably okay.

As for SEARCH permission, that currently covers:

 (1) Finding keys in a keyring tree during a search.

 (2) Permitting keyrings to be joined.

 (3) Invalidation.

But these don't really belong together either, since these actions really
need to be controlled separately.

Finally, there are number of special cases to do with granting the
administrator special rights to invalidate or clear keys that I would like
to handle with the ACL rather than key flags and special checks.


===============
WHAT IS CHANGED
===============

The SETATTR permission is split to create two new permissions:

 (1) SET_SECURITY - which allows the key's owner, group and ACL to be
     changed and a restriction to be placed on a keyring.

 (2) REVOKE - which allows a key to be revoked.

The SEARCH permission is split to create:

 (1) SEARCH - which allows a keyring to be search and a key to be found.

 (2) JOIN - which allows a keyring to be joined as a session keyring.

 (3) INVAL - which allows a key to be invalidated.

The WRITE permission is also split to create:

 (1) WRITE - which allows a key's content to be altered and links to be
     added, removed and replaced in a keyring.

 (2) CLEAR - which allows a keyring to be cleared completely.  This is
     split out to make it possible to give just this to an administrator.

 (3) REVOKE - see above.


Keys acquire ACLs which consist of a series of ACEs, and all that apply are
unioned together.  An ACE specifies a subject, such as:

 (*) Possessor - permitted to anyone who 'possesses' a key
 (*) Owner - permitted to the key owner
 (*) Group - permitted to the key group
 (*) Everyone - permitted to everyone

Note that 'Other' has been replaced with 'Everyone' on the assumption that
you wouldn't grant a permit to 'Other' that you wouldn't also grant to
everyone else.

Further subjects may be made available by later patches.

The ACE also specifies a permissions mask.  The set of permissions is now:

	VIEW		Can view the key metadata
	READ		Can read the key content
	WRITE		Can update/modify the key content
	SEARCH		Can find the key by searching/requesting
	LINK		Can make a link to the key
	SET_SECURITY	Can change owner, ACL, expiry
	INVAL		Can invalidate
	REVOKE		Can revoke
	JOIN		Can join this keyring
	CLEAR		Can clear this keyring


The KEYCTL_SETPERM function is then deprecated.

The KEYCTL_SET_TIMEOUT function then is permitted if SET_SECURITY is set,
or if the caller has a valid instantiation auth token.

The KEYCTL_INVALIDATE function then requires INVAL.

The KEYCTL_REVOKE function then requires REVOKE.

The KEYCTL_JOIN_SESSION_KEYRING function then requires JOIN to join an
existing keyring.

The JOIN permission is enabled by default for session keyrings and manually
created keyrings only.


======================
BACKWARD COMPATIBILITY
======================

To maintain backward compatibility, KEYCTL_SETPERM will translate the
permissions mask it is given into a new ACL for a key - unless
KEYCTL_SET_ACL has been called on that key, in which case an error will be
returned.

It will convert possessor, owner, group and other permissions into separate
ACEs, if each portion of the mask is non-zero.

SETATTR permission turns on all of INVAL, REVOKE and SET_SECURITY.  WRITE
permission turns on WRITE, REVOKE and, if a keyring, CLEAR.  JOIN is turned
on if a keyring is being altered.

The KEYCTL_DESCRIBE function translates the ACL back into a permissions
mask to return depending on possessor, owner, group and everyone ACEs.

It will make the following mappings:

 (1) INVAL, JOIN -> SEARCH

 (2) SET_SECURITY -> SETATTR

 (3) REVOKE -> WRITE if SETATTR isn't already set

 (4) CLEAR -> WRITE

Note that the value subsequently returned by KEYCTL_DESCRIBE may not match
the value set with KEYCTL_SETATTR.


=======
TESTING
=======

This passes the keyutils testsuite for all but a couple of tests:

 (1) tests/keyctl/dh_compute/badargs: The first wrong-key-type test now
     returns EOPNOTSUPP rather than ENOKEY as READ permission isn't removed
     if the type doesn't have ->read().  You still can't actually read the
     key.

 (2) tests/keyctl/permitting/valid: The view-other-permissions test doesn't
     work as Other has been replaced with Everyone in the ACL.

Signed-off-by: David Howells <dhowells@redhat.com>
2019-06-27 23:03:07 +01:00
David Howells
a58946c158 keys: Pass the network namespace into request_key mechanism
Create a request_key_net() function and use it to pass the network
namespace domain tag into DNS revolver keys and rxrpc/AFS keys so that keys
for different domains can coexist in the same keyring.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: netdev@vger.kernel.org
cc: linux-nfs@vger.kernel.org
cc: linux-cifs@vger.kernel.org
cc: linux-afs@lists.infradead.org
2019-06-27 23:02:12 +01:00
Zhengyuan Liu
ee102584ef fs/afs: use struct_size() in kzalloc()
As Gustavo said in other patches doing the same replace, we can now
use the new struct_size() helper to avoid leaving these open-coded and
prone to type mistake.

Signed-off-by: Zhengyuan Liu <liuzhengyuan@kylinos.cn>
Signed-off-by: David Howells <dhowells@redhat.com>
2019-06-20 18:12:17 +01:00
David Howells
4521819369 afs: Trace afs_server usage
Add a tracepoint (afs_server) to track the afs_server object usage count.

Signed-off-by: David Howells <dhowells@redhat.com>
2019-06-20 18:12:17 +01:00
David Howells
051d25250b afs: Add some callback management tracepoints
Add a couple of tracepoints to track callback management:

 (1) afs_cb_miss - Logs when we were unable to apply a callback, either due
     to the inode being discarded or due to a competing thread applying a
     callback first.

 (2) afs_cb_break - Logs when we attempted to clear the noted callback
     promise, either due to the server explicitly breaking the callback,
     the callback promise lapsing or a local event obsoleting it.

Signed-off-by: David Howells <dhowells@redhat.com>
2019-06-20 18:12:16 +01:00
David Howells
fa59f52f5b afs: afs_unlink() doesn't need to check dentry->d_inode
Don't check that dentry->d_inode is valid in afs_unlink().  We should be
able to take that as given.

This caused Smatch to issue the following warning:

	fs/afs/dir.c:1392 afs_unlink() error: we previously assumed 'vnode' could be null (see line 1375)

Reported-by: kbuild test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2019-06-20 18:12:16 +01:00
David Howells
2cd42d19cf afs: Fix setting of i_blocks
The setting of i_blocks, which is calculated from i_size, has got
accidentally misordered relative to the setting of i_size when initially
setting up an inode.  Further, i_blocks isn't updated by afs_apply_status()
when the size is updated.

To fix this, break the i_size/i_blocks setting out into a helper function
and call it from both places.

Fixes: a58823ac45 ("afs: Fix application of status and callback to be under same lock")
Signed-off-by: David Howells <dhowells@redhat.com>
2019-06-20 18:12:02 +01:00
David Howells
90fa9b6452 afs: Fix uninitialised spinlock afs_volume::cb_break_lock
Fix the cb_break_lock spinlock in afs_volume struct by initialising it when
the volume record is allocated.

Also rename the lock to cb_v_break_lock to distinguish it from the lock of
the same name in the afs_server struct.

Without this, the following trace may be observed when a volume-break
callback is received:

  INFO: trying to register non-static key.
  the code is fine but needs lockdep annotation.
  turning off the locking correctness validator.
  CPU: 2 PID: 50 Comm: kworker/2:1 Not tainted 5.2.0-rc1-fscache+ #3045
  Hardware name: ASUS All Series/H97-PLUS, BIOS 2306 10/09/2014
  Workqueue: afs SRXAFSCB_CallBack
  Call Trace:
   dump_stack+0x67/0x8e
   register_lock_class+0x23b/0x421
   ? check_usage_forwards+0x13c/0x13c
   __lock_acquire+0x89/0xf73
   lock_acquire+0x13b/0x166
   ? afs_break_callbacks+0x1b2/0x3dd
   _raw_write_lock+0x2c/0x36
   ? afs_break_callbacks+0x1b2/0x3dd
   afs_break_callbacks+0x1b2/0x3dd
   ? trace_event_raw_event_afs_server+0x61/0xac
   SRXAFSCB_CallBack+0x11f/0x16c
   process_one_work+0x2c5/0x4ee
   ? worker_thread+0x234/0x2ac
   worker_thread+0x1d8/0x2ac
   ? cancel_delayed_work_sync+0xf/0xf
   kthread+0x11f/0x127
   ? kthread_park+0x76/0x76
   ret_from_fork+0x24/0x30

Fixes: 68251f0a68 ("afs: Fix whole-volume callback handling")
Signed-off-by: David Howells <dhowells@redhat.com>
2019-06-20 16:49:35 +01:00
David Howells
a6853b9ce8 afs: Fix vlserver record corruption
Because I made the afs_call struct share pointers to an afs_server object
and an afs_vlserver object to save space, afs_put_call() calls
afs_put_server() on afs_vlserver object (which is only meant for the
afs_server object) because it sees that call->server isn't NULL.

This means that the afs_vlserver object gets unpredictably and randomly
modified, depending on what config options are set (such as lockdep).

Fix this by getting rid of the union and having two non-overlapping
pointers in the afs_call struct.

Fixes: ffba718e93 ("afs: Get rid of afs_call::reply[]")
Signed-off-by: David Howells <dhowells@redhat.com>
2019-06-20 16:49:35 +01:00
David Howells
3647e42b55 afs: Fix over zealous "vnode modified" warnings
Occasionally, warnings like this:

	vnode modified 2af7 on {10000b:1} [exp 2af2] YFS.FetchStatus(vnode)

are emitted into the kernel log.  This indicates that when we were applying
the updated vnode (file) status retrieved from the server to an inode we
saw that the data version number wasn't what we were expecting (in this
case it's 0x2af7 rather than 0x2af2).

We've usually received a callback from the server prior to this point - or
the callback promise has lapsed - so the warning is merely informative and
the state is to be expected.

Fix this by only emitting the warning if the we still think that we have a
valid callback promise and haven't received a callback.

Also change the format slightly so so that the new data version doesn't
look like part of the text, the like is prefixed with "kAFS: " and the
message is ranked as a warning.

Fixes: 31143d5d51 ("AFS: implement basic file write support")
Reported-by: Ian Wienand <iwienand@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2019-06-20 16:49:34 +01:00
Amir Goldstein
49246466a9 fsnotify: move fsnotify_nameremove() hook out of d_delete()
d_delete() was piggy backed for the fsnotify_nameremove() hook when
in fact not all callers of d_delete() care about fsnotify events.

For all callers of d_delete() that may be interested in fsnotify events,
we made sure to call one of fsnotify_{unlink,rmdir}() hooks before
calling d_delete().

Now we can move the fsnotify_nameremove() call from d_delete() to the
fsnotify_{unlink,rmdir}() hooks.

Two explicit calls to fsnotify_nameremove() from nfs/afs sillyrename
are also removed. This will cause a change of behavior - nfs/afs will
NOT generate an fsnotify delete event when renaming over a positive
dentry.  This change is desirable, because it is consistent with the
behavior of all other filesystems.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2019-06-20 14:47:44 +02:00
David S. Miller
a6cdeeb16b Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Some ISDN files that got removed in net-next had some changes
done in mainline, take the removals.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-07 11:00:14 -07:00
Florian Westphal
35ebfc22fe afs: do not send list of client addresses
David Howells says:
  I'm told that there's not really any point populating the list.
  Current OpenAFS ignores it, as does AuriStor - and IBM AFS 3.6 will
  do the right thing.
  The list is actually useless as it's the client's view of the world,
  not the servers, so if there's any NAT in the way its contents are
  invalid.  Further, it doesn't support IPv6 addresses.

  On that basis, feel free to make it an empty list and remove all the
  interface enumeration.

V1 of this patch reworked the function to use a new helper for the
ifa_list iteration to avoid sparse warnings once the proper __rcu
annotations get added in struct in_device later.

But, in light of the above, just remove afs_get_ipv4_interfaces.

Compile tested only.

Cc: David Howells <dhowells@redhat.com>
Cc: linux-afs@lists.infradead.org
Signed-off-by: Florian Westphal <fw@strlen.de>
Tested-by: David Howells <dhowells@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-02 18:06:26 -07:00
Thomas Gleixner
2874c5fd28 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:32 -07:00
Thomas Gleixner
b4d0d230cc treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 36
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public licence as published by
  the free software foundation either version 2 of the licence or at
  your option any later version

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 114 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190520170857.552531963@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-24 17:27:11 +02:00
Thomas Gleixner
ec8f24b7fa treewide: Add SPDX license identifier - Makefile/Kconfig
Add SPDX license identifiers to all Make/Kconfig files which:

 - Have no license information of any form

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 10:50:46 +02:00
David Howells
39db9815da afs: Fix application of the results of a inline bulk status fetch
Fix afs_do_lookup() such that when it does an inline bulk status fetch op,
it will update inodes that are already extant (something that afs_iget()
doesn't do) and to cache permits for each inode created (thereby avoiding a
follow up FS.FetchStatus call to determine this).

Extant inodes need looking up in advance so that their cb_break counters
before and after the operation can be compared.  To this end, the inode
pointers are cached so that they don't need looking up again after the op.

Fixes: 5cf9dd55a0 ("afs: Prospectively look up extra files when doing a single lookup")
Signed-off-by: David Howells <dhowells@redhat.com>
2019-05-16 22:23:21 +01:00
David Howells
b835915325 afs: Pass pre-fetch server and volume break counts into afs_iget5_set()
Pass the server and volume break counts from before the status fetch
operation that queried the attributes of a file into afs_iget5_set() so
that the new vnode's break counters can be initialised appropriately.

This allows detection of a volume or server break that happened whilst we
were fetching the status or setting up the vnode.

Fixes: c435ee3455 ("afs: Overhaul the callback handling")
Signed-off-by: David Howells <dhowells@redhat.com>
2019-05-16 22:23:21 +01:00
David Howells
a38a75581e afs: Fix unlink to handle YFS.RemoveFile2 better
Make use of the status update for the target file that the YFS.RemoveFile2
RPC op returns to correctly update the vnode as to whether the file was
actually deleted or just had nlink reduced.

Fixes: 30062bd13e ("afs: Implement YFS support in the fs client")
Signed-off-by: David Howells <dhowells@redhat.com>
2019-05-16 22:23:21 +01:00
David Howells
61c347ba55 afs: Clear AFS_VNODE_CB_PROMISED if we detect callback expiry
Fix afs_validate() to clear AFS_VNODE_CB_PROMISED on a vnode if we detect
any condition that causes the callback promise to be broken implicitly,
including server break (cb_s_break), volume break (cb_v_break) or callback
expiry.

Fixes: ae3b7361dc ("afs: Fix validation/callback interaction")
Reported-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2019-05-16 22:23:21 +01:00
David Howells
f642404a04 afs: Make vnode->cb_interest RCU safe
Use RCU-based freeing for afs_cb_interest struct objects and use RCU on
vnode->cb_interest.  Use that change to allow afs_check_validity() to use
read_seqbegin_or_lock() instead of read_seqlock_excl().

This also requires the caller of afs_check_validity() to hold the RCU read
lock across the call.

Signed-off-by: David Howells <dhowells@redhat.com>
2019-05-16 22:23:21 +01:00
David Howells
c925bd0ac4 afs: Split afs_validate() so first part can be used under LOOKUP_RCU
Split afs_validate() so that the part that decides if the vnode is still
valid can be used under LOOKUP_RCU conditions from afs_d_revalidate().

Signed-off-by: David Howells <dhowells@redhat.com>
2019-05-16 22:23:21 +01:00
David Howells
7c71245866 afs: Don't save callback version and type fields
Don't save callback version and type fields as the version is about the
format of the callback information and the type is relative to the
particular RPC call.

Signed-off-by: David Howells <dhowells@redhat.com>
2019-05-16 22:23:21 +01:00
David Howells
a58823ac45 afs: Fix application of status and callback to be under same lock
When applying the status and callback in the response of an operation,
apply them in the same critical section so that there's no race between
checking the callback state and checking status-dependent state (such as
the data version).

Fix this by:

 (1) Allocating a joint {status,callback} record (afs_status_cb) before
     calling the RPC function for each vnode for which the RPC reply
     contains a status or a status plus a callback.  A flag is set in the
     record to indicate if a callback was actually received.

 (2) These records are passed into the RPC functions to be filled in.  The
     afs_decode_status() and yfs_decode_status() functions are removed and
     the cb_lock is no longer taken.

 (3) xdr_decode_AFSFetchStatus() and xdr_decode_YFSFetchStatus() no longer
     update the vnode.

 (4) xdr_decode_AFSCallBack() and xdr_decode_YFSCallBack() no longer update
     the vnode.

 (5) vnodes, expected data-version numbers and callback break counters
     (cb_break) no longer need to be passed to the reply delivery
     functions.

     Note that, for the moment, the file locking functions still need
     access to both the call and the vnode at the same time.

 (6) afs_vnode_commit_status() is now given the cb_break value and the
     expected data_version and the task of applying the status and the
     callback to the vnode are now done here.

     This is done under a single taking of vnode->cb_lock.

 (7) afs_pages_written_back() is now called by afs_store_data() rather than
     by the reply delivery function.

     afs_pages_written_back() has been moved to before the call point and
     is now given the first and last page numbers rather than a pointer to
     the call.

 (8) The indicator from YFS.RemoveFile2 as to whether the target file
     actually got removed (status.abort_code == VNOVNODE) rather than
     merely dropping a link is now checked in afs_unlink rather than in
     xdr_decode_YFSFetchStatus().

Supplementary fixes:

 (*) afs_cache_permit() now gets the caller_access mask from the
     afs_status_cb object rather than picking it out of the vnode's status
     record.  afs_fetch_status() returns caller_access through its argument
     list for this purpose also.

 (*) afs_inode_init_from_status() now uses a write lock on cb_lock rather
     than a read lock and now sets the callback inside the same critical
     section.

Fixes: c435ee3455 ("afs: Overhaul the callback handling")
Signed-off-by: David Howells <dhowells@redhat.com>
2019-05-16 16:25:21 +01:00
David Howells
4571577f16 afs: Always get the reply time
Always ask for the reply time from AF_RXRPC as it's used to calculate the
callback expiry time and lock expiry times, so it's needed by most FS
operations.

Signed-off-by: David Howells <dhowells@redhat.com>
2019-05-16 16:25:21 +01:00
David Howells
87182759cd afs: Fix order-1 allocation in afs_do_lookup()
afs_do_lookup() will do an order-1 allocation to allocate status records if
there are more than 39 vnodes to stat.

Fix this by allocating an array of {status,callback} records for each vnode
we want to examine using vmalloc() if larger than a page.

This not only gets rid of the order-1 allocation, but makes it easier to
grow beyond 50 records for YFS servers.  It also allows us to move to
{status,callback} tuples for other calls too and makes it easier to lock
across the application of the status and the callback to the vnode.

Fixes: 5cf9dd55a0 ("afs: Prospectively look up extra files when doing a single lookup")
Signed-off-by: David Howells <dhowells@redhat.com>
2019-05-16 16:25:21 +01:00
David Howells
ffba718e93 afs: Get rid of afs_call::reply[]
Replace the afs_call::reply[] array with a bunch of typed members so that
the compiler can use type-checking on them.  It's also easier for the eye
to see what's going on.

Signed-off-by: David Howells <dhowells@redhat.com>
2019-05-16 16:25:21 +01:00
David Howells
fefb2483dc afs: Don't pass the vnode pointer through into the inline bulk status op
Don't pass the vnode pointer through into the inline bulk status op.  We
want to process the status records outside of it anyway.

Signed-off-by: David Howells <dhowells@redhat.com>
2019-05-16 16:25:21 +01:00