7776 Commits

Author SHA1 Message Date
Darrick J. Wong
a7a0f9a550 xfs: return EINTR when a fatal signal terminates scrub
If the program calling online fsck is terminated with a fatal signal,
bail out to userspace by returning EINTR, not EAGAIN.  EAGAIN is used by
scrubbers to indicate that we should try again with more resources
locked, and not to indicate that the operation was cancelled.  The
miswiring is mostly harmless, but it shows up in the trace data.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-11-16 15:25:02 -08:00
Darrick J. Wong
306195f355 xfs: pivot online scrub away from kmem.[ch]
Convert all the online scrub code to use the Linux slab allocator
functions directly instead of going through the kmem wrappers.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-11-16 15:25:02 -08:00
Darrick J. Wong
fcd2a43488 xfs: initialize the check_owner object fully
Initialize the check_owner list head so that we don't corrupt the list.
Reduce the scope of the object pointer.

Fixes: 858333dcf021 ("xfs: check btree block ownership with bnobt/rmapbt when scrubbing btree")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-11-16 15:25:02 -08:00
Darrick J. Wong
48ff40458f xfs: standardize GFP flags usage in online scrub
Memory allocation usage is the same throughout online fsck -- we want
kernel memory, we have to be able to back out if we can't allocate
memory, and we don't want to spray dmesg with memory allocation failure
reports.  Standardize the GFP flag usage and document these requirements.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-11-16 15:25:01 -08:00
Darrick J. Wong
b255fab0f8 xfs: make AGFL repair function avoid crosslinked blocks
Teach the AGFL repair function to check each block of the proposed AGFL
against the rmap btree.  If the rmapbt finds any mappings that are not
OWN_AG, strike that block from the list.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-11-16 15:25:01 -08:00
Darrick J. Wong
3e59c0103e xfs: log the AGI/AGF buffers when rolling transactions during an AG repair
Currently, the only way to lock an allocation group is to hold the AGI
and AGF buffers.  If a repair needs to roll the transaction while
repairing some AG metadata, it maintains that lock by holding the two
buffers across the transaction roll and joins them afterwards.

However, repair is not like other parts of XFS that employ the bhold -
roll - bjoin sequence because it's possible that the AGI or AGF buffers
are not actually dirty before the roll.  This presents two problems --
First, we need to redirty those buffers to keep them moving along in the
log to avoid pinning the log tail.  Second, a clean buffer log item can
detach from the buffer.  If this happens, the buffer type state is
discarded along with the bli and must be reattached before the next time
the buffer is logged.   If it is not, the logging code will complain and
log recovery will not work properly.

An earlier version of this patch tried to fix the second problem by
re-setting the buffer type in the bli after joining the buffer to the
new transaction, but that looked weird and didn't solve the first
problem.  Instead, solve both problems by logging the buffer before
rolling the transaction.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-11-16 15:25:01 -08:00
Darrick J. Wong
be1317fdb8 xfs: don't track the AGFL buffer in the scrub AG context
While scrubbing an allocation group, we don't need to hold the AGFL
buffer as part of the scrub context.  All that is necessary to lock an
AG is to hold the AGI and AGF buffers, so fix all the existing users of
the AGFL buffer to grab them only when necessary.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-11-16 15:25:01 -08:00
Darrick J. Wong
9a48b4a6fd xfs: fully initialize xfs_da_args in xchk_directory_blocks
While running the online fsck test suite, I noticed the following
assertion in the kernel log (edited for brevity):

XFS: Assertion failed: 0, file: fs/xfs/xfs_health.c, line: 571
------------[ cut here ]------------
WARNING: CPU: 3 PID: 11667 at fs/xfs/xfs_message.c:104 assfail+0x46/0x4a [xfs]
CPU: 3 PID: 11667 Comm: xfs_scrub Tainted: G        W         5.19.0-rc7-xfsx #rc7 6e6475eb29fd9dda3181f81b7ca7ff961d277a40
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.15.0-1 04/01/2014
RIP: 0010:assfail+0x46/0x4a [xfs]
Call Trace:
 <TASK>
 xfs_dir2_isblock+0xcc/0xe0
 xchk_directory_blocks+0xc7/0x420
 xchk_directory+0x53/0xb0
 xfs_scrub_metadata+0x2b6/0x6b0
 xfs_scrubv_metadata+0x35e/0x4d0
 xfs_ioc_scrubv_metadata+0x111/0x160
 xfs_file_ioctl+0x4ec/0xef0
 __x64_sys_ioctl+0x82/0xa0
 do_syscall_64+0x2b/0x80
 entry_SYSCALL_64_after_hwframe+0x46/0xb0

This assertion triggers in xfs_dirattr_mark_sick when the caller passes
in a whichfork value that is neither of XFS_{DATA,ATTR}_FORK.  The cause
of this is that xchk_directory_blocks only partially initializes the
xfs_da_args structure that is passed to xfs_dir2_isblock.  If the data
fork is not correct, the XFS_IS_CORRUPT clause will trigger.  My
development branch reports this failure to the health monitoring
subsystem, which accesses the uninitialized args->whichfork field,
leading the the assertion tripping.  We really shouldn't be passing
random stack contents around, so the solution here is to force the
compiler to zero-initialize the struct.

Found by fuzzing u3.bmx[0].blockcount = middlebit on xfs/1554.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-11-16 15:25:01 -08:00
Dave Chinner
118e021b4b xfs: write page faults in iomap are not buffered writes
When we reserve a delalloc region in xfs_buffered_write_iomap_begin,
we mark the iomap as IOMAP_F_NEW so that the the write context
understands that it allocated the delalloc region.

If we then fail that buffered write, xfs_buffered_write_iomap_end()
checks for the IOMAP_F_NEW flag and if it is set, it punches out
the unused delalloc region that was allocated for the write.

The assumption this code makes is that all buffered write operations
that can allocate space are run under an exclusive lock (i_rwsem).
This is an invalid assumption: page faults in mmap()d regions call
through this same function pair to map the file range being faulted
and this runs only holding the inode->i_mapping->invalidate_lock in
shared mode.

IOWs, we can have races between page faults and write() calls that
fail the nested page cache write operation that result in data loss.
That is, the failing iomap_end call will punch out the data that
the other racing iomap iteration brought into the page cache. This
can be reproduced with generic/34[46] if we arbitrarily fail page
cache copy-in operations from write() syscalls.

Code analysis tells us that the iomap_page_mkwrite() function holds
the already instantiated and uptodate folio locked across the iomap
mapping iterations. Hence the folio cannot be removed from memory
whilst we are mapping the range it covers, and as such we do not
care if the mapping changes state underneath the iomap iteration
loop:

1. if the folio is not already dirty, there is no writeback races
   possible.
2. if we allocated the mapping (delalloc or unwritten), the folio
   cannot already be dirty. See #1.
3. If the folio is already dirty, it must be up to date. As we hold
   it locked, it cannot be reclaimed from memory. Hence we always
   have valid data in the page cache while iterating the mapping.
4. Valid data in the page cache can exist when the underlying
   mapping is DELALLOC, UNWRITTEN or WRITTEN. Having the mapping
   change from DELALLOC->UNWRITTEN or UNWRITTEN->WRITTEN does not
   change the data in the page - it only affects actions if we are
   initialising a new page. Hence #3 applies  and we don't care
   about these extent map transitions racing with
   iomap_page_mkwrite().
5. iomap_page_mkwrite() checks for page invalidation races
   (truncate, hole punch, etc) after it locks the folio. We also
   hold the mapping->invalidation_lock here, and hence the mapping
   cannot change due to extent removal operations while we are
   iterating the folio.

As such, filesystems that don't use bufferheads will never fail
the iomap_folio_mkwrite_iter() operation on the current mapping,
regardless of whether the iomap should be considered stale.

Further, the range we are asked to iterate is limited to the range
inside EOF that the folio spans. Hence, for XFS, we will only map
the exact range we are asked for, and we will only do speculative
preallocation with delalloc if we are mapping a hole at the EOF
page. The iterator will consume the entire range of the folio that
is within EOF, and anything beyond the EOF block cannot be accessed.
We never need to truncate this post-EOF speculative prealloc away in
the context of the iomap_page_mkwrite() iterator because if it
remains unused we'll remove it when the last reference to the inode
goes away.

Hence we don't actually need an .iomap_end() cleanup/error handling
path at all for iomap_page_mkwrite() for XFS. This means we can
separate the page fault processing from the complexity of the
.iomap_end() processing in the buffered write path. This also means
that the buffered write path will also be able to take the
mapping->invalidate_lock as necessary.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2022-11-07 10:09:11 +11:00
Darrick J. Wong
8b972158af xfs: rename XFS_REFC_COW_START to _COWFLAG
We've been (ab)using XFS_REFC_COW_START as both an integer quantity and
a bit flag, even though it's *only* a bit flag.  Rename the variable to
reflect its nature and update the cast target since we're not supposed
to be comparing it to xfs_agblock_t now.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-31 08:58:22 -07:00
Darrick J. Wong
c1ccf967bf xfs: fix uninitialized list head in struct xfs_refcount_recovery
We're supposed to initialize the list head of an object before adding it
to another list.  Fix that, and stop using the kmem_{alloc,free} calls
from the Irix days.

Fixes: 174edb0e46e5 ("xfs: store in-progress CoW allocations in the refcount btree")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-31 08:58:22 -07:00
Darrick J. Wong
f1fdc82078 xfs: fix agblocks check in the cow leftover recovery function
As we've seen, refcount records use the upper bit of the rc_startblock
field to ensure that all the refcount records are at the right side of
the refcount btree.  This works because an AG is never allowed to have
more than (1U << 31) blocks in it.  If we ever encounter a filesystem
claiming to have that many blocks, we absolutely do not want reflink
touching it at all.

However, this test at the start of xfs_refcount_recover_cow_leftovers is
slightly incorrect -- it /should/ be checking that agblocks isn't larger
than the XFS_MAX_CRC_AG_BLOCKS constant, and it should check that the
constant is never large enough to conflict with that CoW flag.

Note that the V5 superblock verifier has not historically rejected
filesystems where agblocks >= XFS_MAX_CRC_AG_BLOCKS, which is why this
ended up in the COW recovery routine.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-31 08:58:21 -07:00
Darrick J. Wong
f62ac3e0ac xfs: check record domain when accessing refcount records
Now that we've separated the startblock and CoW/shared extent domain in
the incore refcount record structure, check the domain whenever we
retrieve a record to ensure that it's still in the domain that we want.
Depending on the circumstances, a change in domain either means we're
done processing or that we've found a corruption and need to fail out.

The refcount check in xchk_xref_is_cow_staging is redundant since
_get_rec has done that for a long time now, so we can get rid of it.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-31 08:58:21 -07:00
Darrick J. Wong
68d0f38917 xfs: remove XFS_FIND_RCEXT_SHARED and _COW
Now that we have an explicit enum for shared and CoW staging extents, we
can get rid of the old FIND_RCEXT flags.  Omit a couple of conversions
that disappear in the next patches.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-31 08:58:21 -07:00
Darrick J. Wong
f492135df0 xfs: refactor domain and refcount checking
Create a helper function to ensure that CoW staging extent records have
a single refcount and that shared extent records have more than 1
refcount.  We'll put this to more use in the next patch.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-31 08:58:21 -07:00
Darrick J. Wong
571423a162 xfs: report refcount domain in tracepoints
Now that we've broken out the startblock and shared/cow domain in the
incore refcount extent record structure, update the tracepoints to
report the domain.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-31 08:58:21 -07:00
Darrick J. Wong
9a50ee4f8d xfs: track cow/shared record domains explicitly in xfs_refcount_irec
Just prior to committing the reflink code into upstream, the xfs
maintainer at the time requested that I find a way to shard the refcount
records into two domains -- one for records tracking shared extents, and
a second for tracking CoW staging extents.  The idea here was to
minimize mount time CoW reclamation by pushing all the CoW records to
the right edge of the keyspace, and it was accomplished by setting the
upper bit in rc_startblock.  We don't allow AGs to have more than 2^31
blocks, so the bit was free.

Unfortunately, this was a very late addition to the codebase, so most of
the refcount record processing code still treats rc_startblock as a u32
and pays no attention to whether or not the upper bit (the cow flag) is
set.  This is a weakness is theoretically exploitable, since we're not
fully validating the incoming metadata records.

Fuzzing demonstrates practical exploits of this weakness.  If the cow
flag of a node block key record is corrupted, a lookup operation can go
to the wrong record block and start returning records from the wrong
cow/shared domain.  This causes the math to go all wrong (since cow
domain is still implicit in the upper bit of rc_startblock) and we can
crash the kernel by tricking xfs into jumping into a nonexistent AG and
tripping over xfs_perag_get(mp, <nonexistent AG>) returning NULL.

To fix this, start tracking the domain as an explicit part of struct
xfs_refcount_irec, adjust all refcount functions to check the domain
of a returned record, and alter the function definitions to accept them
where necessary.

Found by fuzzing keys[2].cowflag = add in xfs/464.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-31 08:58:21 -07:00
Darrick J. Wong
5a8c345ca8 xfs: refactor refcount record usage in xchk_refcountbt_rec
Consolidate the open-coded xfs_refcount_irec fields into an actual
struct and use the existing _btrec_to_irec to decode the ondisk record.
This will reduce code churn in the next patch.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-31 08:58:21 -07:00
Darrick J. Wong
9e7e2436c1 xfs: move _irec structs to xfs_types.h
Structure definitions for incore objects do not belong in the ondisk
format header.  Move them to the incore types header where they belong.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-31 08:58:20 -07:00
Darrick J. Wong
8edbe0cf8b xfs: check deferred refcount op continuation parameters
If we're in the middle of a deferred refcount operation and decide to
roll the transaction to avoid overflowing the transaction space, we need
to check the new agbno/aglen parameters that we're about to record in
the new intent.  Specifically, we need to check that the new extent is
completely within the filesystem, and that continuation does not put us
into a different AG.

If the keys of a node block are wrong, the lookup to resume an
xfs_refcount_adjust_extents operation can put us into the wrong record
block.  If this happens, we might not find that we run out of aglen at
an exact record boundary, which will cause the loop control to do the
wrong thing.

The previous patch should take care of that problem, but let's add this
extra sanity check to stop corruption problems sooner than later.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-31 08:58:20 -07:00
Darrick J. Wong
b65e08f83b xfs: create a predicate to verify per-AG extents
Create a predicate function to verify that a given agbno/blockcount pair
fit entirely within a single allocation group and don't suffer
mathematical overflows.  Refactor the existng open-coded logic; we're
going to add more calls to this function in the next patch.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-31 08:58:20 -07:00
Darrick J. Wong
f850995f60 xfs: make sure aglen never goes negative in xfs_refcount_adjust_extents
Prior to calling xfs_refcount_adjust_extents, we trimmed agbno/aglen
such that the end of the range would not be in the middle of a refcount
record.  If this is no longer the case, something is seriously wrong
with the btree.  Bail out with a corruption error.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-31 08:58:20 -07:00
Darrick J. Wong
950f0d50ee xfs: dump corrupt recovered log intent items to dmesg consistently
If log recovery decides that an intent item is corrupt and wants to
abort the mount, capture a hexdump of the corrupt log item in the kernel
log for further analysis.  Some of the log item code already did this,
so we're fixing the rest to do it consistently.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-31 08:58:20 -07:00
Darrick J. Wong
921ed96b4f xfs: actually abort log recovery on corrupt intent-done log items
If log recovery picks up intent-done log items that are not of the
correct size it needs to abort recovery and fail the mount.  Debug
assertions are not good enough.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-31 08:58:20 -07:00
Darrick J. Wong
3c5aaaced9 xfs: refactor all the EFI/EFD log item sizeof logic
Refactor all the open-coded sizeof logic for EFI/EFD log item and log
format structures into common helper functions whose names reflect the
struct names.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-31 08:58:20 -07:00
Darrick J. Wong
03a7485cd7 xfs: fix memcpy fortify errors in EFI log format copying
Starting in 6.1, CONFIG_FORTIFY_SOURCE checks the length parameter of
memcpy.  Since we're already fixing problems with BUI item copying, we
should fix it everything else.

An extra difficulty here is that the ef[id]_extents arrays are declared
as single-element arrays.  This is not the convention for flex arrays in
the modern kernel, and it causes all manner of problems with static
checking tools, since they often cannot tell the difference between a
single element array and a flex array.

So for starters, change those array[1] declarations to array[]
declarations to signal that they are proper flex arrays and adjust all
the "size-1" expressions to fit the new declaration style.

Next, refactor the xfs_efi_copy_format function to handle the copying of
the head and the flex array members separately.  While we're at it, fix
a minor validation deficiency in the recovery function.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-31 08:58:20 -07:00
Darrick J. Wong
b45ca961e9 xfs: fix memcpy fortify errors in RUI log format copying
Starting in 6.1, CONFIG_FORTIFY_SOURCE checks the length parameter of
memcpy.  Since we're already fixing problems with BUI item copying, we
should fix it everything else.

Refactor the xfs_rui_copy_format function to handle the copying of the
head and the flex array members separately.  While we're at it, fix a
minor validation deficiency in the recovery function.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-31 08:58:19 -07:00
Darrick J. Wong
a38935c03c xfs: fix memcpy fortify errors in CUI log format copying
Starting in 6.1, CONFIG_FORTIFY_SOURCE checks the length parameter of
memcpy.  Since we're already fixing problems with BUI item copying, we
should fix it everything else.

Refactor the xfs_cui_copy_format function to handle the copying of the
head and the flex array members separately.  While we're at it, fix a
minor validation deficiency in the recovery function.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-31 08:58:19 -07:00
Darrick J. Wong
a38ebce1da xfs: fix memcpy fortify errors in BUI log format copying
Starting in 6.1, CONFIG_FORTIFY_SOURCE checks the length parameter of
memcpy.  Unfortunately, it doesn't handle flex arrays correctly:

------------[ cut here ]------------
memcpy: detected field-spanning write (size 48) of single field "dst_bui_fmt" at fs/xfs/xfs_bmap_item.c:628 (size 16)

Fix this by refactoring the xfs_bui_copy_format function to handle the
copying of the head and the flex array members separately.  While we're
at it, fix a minor validation deficiency in the recovery function.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-31 08:58:19 -07:00
Darrick J. Wong
59da7ff49d xfs: fix validation in attr log item recovery
Before we start fixing all the complaints about memcpy'ing log items
around, let's fix some inadequate validation in the xattr log item
recovery code and get rid of the (now trivial) copy_format function.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-31 08:58:19 -07:00
Darrick J. Wong
47ba8cc7b4 xfs: fix incorrect return type for fsdax fault handlers
The kernel robot complained about this:

>> fs/xfs/xfs_file.c:1266:31: sparse: sparse: incorrect type in return expression (different base types) @@     expected int @@     got restricted vm_fault_t @@
   fs/xfs/xfs_file.c:1266:31: sparse:     expected int
   fs/xfs/xfs_file.c:1266:31: sparse:     got restricted vm_fault_t
   fs/xfs/xfs_file.c:1314:21: sparse: sparse: incorrect type in assignment (different base types) @@     expected restricted vm_fault_t [usertype] ret @@     got int @@
   fs/xfs/xfs_file.c:1314:21: sparse:     expected restricted vm_fault_t [usertype] ret
   fs/xfs/xfs_file.c:1314:21: sparse:     got int

Fix the incorrect return type for these two functions.

While we're at it, make the !fsdax version return VM_FAULT_SIGBUS
because a zero return value will cause some callers to try to lock
vmf->page, which we never set here.

Fixes: ea6c49b784f0 ("xfs: support CoW in fsdax mode")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-10-31 08:51:45 -07:00
Allison Henderson
e07ee6fe21 xfs: increase rename inode reservation
xfs_rename can update up to 5 inodes: src_dp, target_dp, src_ip, target_ip
and wip.  So we need to increase the inode reservation to match.

Signed-off-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2022-10-26 13:02:24 -07:00
Li Zetao
d08af40340 xfs: Fix unreferenced object reported by kmemleak in xfs_sysfs_init()
kmemleak reported a sequence of memory leaks, and one of them indicated we
failed to free a pointer:
  comm "mount", pid 19610, jiffies 4297086464 (age 60.635s)
    hex dump (first 8 bytes):
      73 64 61 00 81 88 ff ff                          sda.....
    backtrace:
      [<00000000d77f3e04>] kstrdup_const+0x46/0x70
      [<00000000e51fa804>] kobject_set_name_vargs+0x2f/0xb0
      [<00000000247cd595>] kobject_init_and_add+0xb0/0x120
      [<00000000f9139aaf>] xfs_mountfs+0x367/0xfc0
      [<00000000250d3caf>] xfs_fs_fill_super+0xa16/0xdc0
      [<000000008d873d38>] get_tree_bdev+0x256/0x390
      [<000000004881f3fa>] vfs_get_tree+0x41/0xf0
      [<000000008291ab52>] path_mount+0x9b3/0xdd0
      [<0000000022ba8f2d>] __x64_sys_mount+0x190/0x1d0

As mentioned in kobject_init_and_add() comment, if this function
returns an error, kobject_put() must be called to properly clean up
the memory associated with the object. Apparently, xfs_sysfs_init()
does not follow such a requirement. When kobject_init_and_add()
returns an error, the space of kobj->kobject.name alloced by
kstrdup_const() is unfree, which will cause the above stack.

Fix it by adding kobject_put() when kobject_init_and_add returns an
error.

Fixes: a31b1d3d89e4 ("xfs: add xfs_mount sysfs kobject")
Signed-off-by: Li Zetao <lizetao1@huawei.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2022-10-20 09:42:56 -07:00
Zeng Heng
cf4f4c12de xfs: fix memory leak in xfs_errortag_init
When `xfs_sysfs_init` returns failed, `mp->m_errortag` needs to free.
Otherwise kmemleak would report memory leak after mounting xfs image:

unreferenced object 0xffff888101364900 (size 192):
  comm "mount", pid 13099, jiffies 4294915218 (age 335.207s)
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<00000000f08ad25c>] __kmalloc+0x41/0x1b0
    [<00000000dca9aeb6>] kmem_alloc+0xfd/0x430
    [<0000000040361882>] xfs_errortag_init+0x20/0x110
    [<00000000b384a0f6>] xfs_mountfs+0x6ea/0x1a30
    [<000000003774395d>] xfs_fs_fill_super+0xe10/0x1a80
    [<000000009cf07b6c>] get_tree_bdev+0x3e7/0x700
    [<00000000046b5426>] vfs_get_tree+0x8e/0x2e0
    [<00000000952ec082>] path_mount+0xf8c/0x1990
    [<00000000beb1f838>] do_mount+0xee/0x110
    [<000000000e9c41bb>] __x64_sys_mount+0x14b/0x1f0
    [<00000000f7bb938e>] do_syscall_64+0x3b/0x90
    [<000000003fcd67a9>] entry_SYSCALL_64_after_hwframe+0x63/0xcd

Fixes: c68401011522 ("xfs: expose errortag knobs via sysfs")
Signed-off-by: Zeng Heng <zengheng4@huawei.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2022-10-20 09:42:56 -07:00
Colin Ian King
fc93812c72 xfs: remove redundant pointer lip
The assignment to pointer lip is not really required, the pointer lip
is redundant and can be removed.

Cleans up clang-scan warning:
warning: Although the value stored to 'lip' is used in the enclosing
expression, the value is never actually read from 'lip'
[deadcode.DeadStores]

Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2022-10-20 09:42:56 -07:00
Guo Xuenan
13cf24e006 xfs: fix exception caused by unexpected illegal bestcount in leaf dir
For leaf dir, In most cases, there should be as many bestfree slots
as the dir data blocks that can fit under i_size (except for [1]).

Root cause is we don't examin the number bestfree slots, when the slots
number less than dir data blocks, if we need to allocate new dir data
block and update the bestfree array, we will use the dir block number as
index to assign bestfree array, while we did not check the leaf buf
boundary which may cause UAF or other memory access problem. This issue
can also triggered with test cases xfs/473 from fstests.

According to Dave Chinner & Darrick's suggestion, adding buffer verifier
to detect this abnormal situation in time.
Simplify the testcase for fstest xfs/554 [1]

The error log is shown as follows:
==================================================================
BUG: KASAN: use-after-free in xfs_dir2_leaf_addname+0x1995/0x1ac0
Write of size 2 at addr ffff88810168b000 by task touch/1552
CPU: 5 PID: 1552 Comm: touch Not tainted 6.0.0-rc3+ #101
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
1.13.0-1ubuntu1.1 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0x4d/0x66
 print_report.cold+0xf6/0x691
 kasan_report+0xa8/0x120
 xfs_dir2_leaf_addname+0x1995/0x1ac0
 xfs_dir_createname+0x58c/0x7f0
 xfs_create+0x7af/0x1010
 xfs_generic_create+0x270/0x5e0
 path_openat+0x270b/0x3450
 do_filp_open+0x1cf/0x2b0
 do_sys_openat2+0x46b/0x7a0
 do_sys_open+0xb7/0x130
 do_syscall_64+0x35/0x80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fe4d9e9312b
Code: 25 00 00 41 00 3d 00 00 41 00 74 4b 64 8b 04 25 18 00 00 00 85 c0
75 67 44 89 e2 48 89 ee bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00
f0 ff ff 0f 87 91 00 00 00 48 8b 4c 24 28 64 48 33 0c 25
RSP: 002b:00007ffda4c16c20 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007fe4d9e9312b
RDX: 0000000000000941 RSI: 00007ffda4c17f33 RDI: 00000000ffffff9c
RBP: 00007ffda4c17f33 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000000001b6 R11: 0000000000000246 R12: 0000000000000941
R13: 00007fe4d9f631a4 R14: 00007ffda4c17f33 R15: 0000000000000000
 </TASK>

The buggy address belongs to the physical page:
page:ffffea000405a2c0 refcount:0 mapcount:0 mapping:0000000000000000
index:0x0 pfn:0x10168b
flags: 0x2fffff80000000(node=0|zone=2|lastcpupid=0x1fffff)
raw: 002fffff80000000 ffffea0004057788 ffffea000402dbc8 0000000000000000
raw: 0000000000000000 0000000000170000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88810168af00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88810168af80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88810168b000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                   ^
 ffff88810168b080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88810168b100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================
Disabling lock debugging due to kernel taint
00000000: 58 44 44 33 5b 53 35 c2 00 00 00 00 00 00 00 78
XDD3[S5........x
XFS (sdb): Internal error xfs_dir2_data_use_free at line 1200 of file
fs/xfs/libxfs/xfs_dir2_data.c.  Caller
xfs_dir2_data_use_free+0x28a/0xeb0
CPU: 5 PID: 1552 Comm: touch Tainted: G    B              6.0.0-rc3+
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
1.13.0-1ubuntu1.1 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0x4d/0x66
 xfs_corruption_error+0x132/0x150
 xfs_dir2_data_use_free+0x198/0xeb0
 xfs_dir2_leaf_addname+0xa59/0x1ac0
 xfs_dir_createname+0x58c/0x7f0
 xfs_create+0x7af/0x1010
 xfs_generic_create+0x270/0x5e0
 path_openat+0x270b/0x3450
 do_filp_open+0x1cf/0x2b0
 do_sys_openat2+0x46b/0x7a0
 do_sys_open+0xb7/0x130
 do_syscall_64+0x35/0x80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fe4d9e9312b
Code: 25 00 00 41 00 3d 00 00 41 00 74 4b 64 8b 04 25 18 00 00 00 85 c0
75 67 44 89 e2 48 89 ee bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00
f0 ff ff 0f 87 91 00 00 00 48 8b 4c 24 28 64 48 33 0c 25
RSP: 002b:00007ffda4c16c20 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007fe4d9e9312b
RDX: 0000000000000941 RSI: 00007ffda4c17f46 RDI: 00000000ffffff9c
RBP: 00007ffda4c17f46 R08: 0000000000000000 R09: 0000000000000001
R10: 00000000000001b6 R11: 0000000000000246 R12: 0000000000000941
R13: 00007fe4d9f631a4 R14: 00007ffda4c17f46 R15: 0000000000000000
 </TASK>
XFS (sdb): Corruption detected. Unmount and run xfs_repair

[1] https://lore.kernel.org/all/20220928095355.2074025-1-guoxuenan@huawei.com/
Reviewed-by: Hou Tao <houtao1@huawei.com>
Signed-off-by: Guo Xuenan <guoxuenan@huawei.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2022-10-20 09:42:56 -07:00
Christian Brauner
cac2f8b8d8
fs: rename current get acl method
The current way of setting and getting posix acls through the generic
xattr interface is error prone and type unsafe. The vfs needs to
interpret and fixup posix acls before storing or reporting it to
userspace. Various hacks exist to make this work. The code is hard to
understand and difficult to maintain in it's current form. Instead of
making this work by hacking posix acls through xattr handlers we are
building a dedicated posix acl api around the get and set inode
operations. This removes a lot of hackiness and makes the codepaths
easier to maintain. A lot of background can be found in [1].

The current inode operation for getting posix acls takes an inode
argument but various filesystems (e.g., 9p, cifs, overlayfs) need access
to the dentry. In contrast to the ->set_acl() inode operation we cannot
simply extend ->get_acl() to take a dentry argument. The ->get_acl()
inode operation is called from:

acl_permission_check()
-> check_acl()
   -> get_acl()

which is part of generic_permission() which in turn is part of
inode_permission(). Both generic_permission() and inode_permission() are
called in the ->permission() handler of various filesystems (e.g.,
overlayfs). So simply passing a dentry argument to ->get_acl() would
amount to also having to pass a dentry argument to ->permission(). We
should avoid this unnecessary change.

So instead of extending the existing inode operation rename it from
->get_acl() to ->get_inode_acl() and add a ->get_acl() method later that
passes a dentry argument and which filesystems that need access to the
dentry can implement instead of ->get_inode_acl(). Filesystems like cifs
which allow setting and getting posix acls but not using them for
permission checking during lookup can simply not implement
->get_inode_acl().

This is intended to be a non-functional change.

Link: https://lore.kernel.org/all/20220801145520.1532837-1-brauner@kernel.org [1]
Suggested-by/Inspired-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
2022-10-20 10:13:27 +02:00
Christian Brauner
138060ba92
fs: pass dentry to set acl method
The current way of setting and getting posix acls through the generic
xattr interface is error prone and type unsafe. The vfs needs to
interpret and fixup posix acls before storing or reporting it to
userspace. Various hacks exist to make this work. The code is hard to
understand and difficult to maintain in it's current form. Instead of
making this work by hacking posix acls through xattr handlers we are
building a dedicated posix acl api around the get and set inode
operations. This removes a lot of hackiness and makes the codepaths
easier to maintain. A lot of background can be found in [1].

Since some filesystem rely on the dentry being available to them when
setting posix acls (e.g., 9p and cifs) they cannot rely on set acl inode
operation. But since ->set_acl() is required in order to use the generic
posix acl xattr handlers filesystems that do not implement this inode
operation cannot use the handler and need to implement their own
dedicated posix acl handlers.

Update the ->set_acl() inode method to take a dentry argument. This
allows all filesystems to rely on ->set_acl().

As far as I can tell all codepaths can be switched to rely on the dentry
instead of just the inode. Note that the original motivation for passing
the dentry separate from the inode instead of just the dentry in the
xattr handlers was because of security modules that call
security_d_instantiate(). This hook is called during
d_instantiate_new(), d_add(), __d_instantiate_anon(), and
d_splice_alias() to initialize the inode's security context and possibly
to set security.* xattrs. Since this only affects security.* xattrs this
is completely irrelevant for posix acls.

Link: https://lore.kernel.org/all/20220801145520.1532837-1-brauner@kernel.org [1]
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
2022-10-19 12:55:42 +02:00
Darrick J. Wong
97cf79677e xfs: avoid a UAF when log intent item recovery fails
KASAN reported a UAF bug when I was running xfs/235:

 BUG: KASAN: use-after-free in xlog_recover_process_intents+0xa77/0xae0 [xfs]
 Read of size 8 at addr ffff88804391b360 by task mount/5680

 CPU: 2 PID: 5680 Comm: mount Not tainted 6.0.0-xfsx #6.0.0 77e7b52a4943a975441e5ac90a5ad7748b7867f6
 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.15.0-1 04/01/2014
 Call Trace:
  <TASK>
  dump_stack_lvl+0x34/0x44
  print_report.cold+0x2cc/0x682
  kasan_report+0xa3/0x120
  xlog_recover_process_intents+0xa77/0xae0 [xfs fb841c7180aad3f8359438576e27867f5795667e]
  xlog_recover_finish+0x7d/0x970 [xfs fb841c7180aad3f8359438576e27867f5795667e]
  xfs_log_mount_finish+0x2d7/0x5d0 [xfs fb841c7180aad3f8359438576e27867f5795667e]
  xfs_mountfs+0x11d4/0x1d10 [xfs fb841c7180aad3f8359438576e27867f5795667e]
  xfs_fs_fill_super+0x13d5/0x1a80 [xfs fb841c7180aad3f8359438576e27867f5795667e]
  get_tree_bdev+0x3da/0x6e0
  vfs_get_tree+0x7d/0x240
  path_mount+0xdd3/0x17d0
  __x64_sys_mount+0x1fa/0x270
  do_syscall_64+0x2b/0x80
  entry_SYSCALL_64_after_hwframe+0x46/0xb0
 RIP: 0033:0x7ff5bc069eae
 Code: 48 8b 0d 85 1f 0f 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 52 1f 0f 00 f7 d8 64 89 01 48
 RSP: 002b:00007ffe433fd448 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007ff5bc069eae
 RDX: 00005575d7213290 RSI: 00005575d72132d0 RDI: 00005575d72132b0
 RBP: 00005575d7212fd0 R08: 00005575d7213230 R09: 00005575d7213fe0
 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
 R13: 00005575d7213290 R14: 00005575d72132b0 R15: 00005575d7212fd0
  </TASK>

 Allocated by task 5680:
  kasan_save_stack+0x1e/0x40
  __kasan_slab_alloc+0x66/0x80
  kmem_cache_alloc+0x152/0x320
  xfs_rui_init+0x17a/0x1b0 [xfs]
  xlog_recover_rui_commit_pass2+0xb9/0x2e0 [xfs]
  xlog_recover_items_pass2+0xe9/0x220 [xfs]
  xlog_recover_commit_trans+0x673/0x900 [xfs]
  xlog_recovery_process_trans+0xbe/0x130 [xfs]
  xlog_recover_process_data+0x103/0x2a0 [xfs]
  xlog_do_recovery_pass+0x548/0xc60 [xfs]
  xlog_do_log_recovery+0x62/0xc0 [xfs]
  xlog_do_recover+0x73/0x480 [xfs]
  xlog_recover+0x229/0x460 [xfs]
  xfs_log_mount+0x284/0x640 [xfs]
  xfs_mountfs+0xf8b/0x1d10 [xfs]
  xfs_fs_fill_super+0x13d5/0x1a80 [xfs]
  get_tree_bdev+0x3da/0x6e0
  vfs_get_tree+0x7d/0x240
  path_mount+0xdd3/0x17d0
  __x64_sys_mount+0x1fa/0x270
  do_syscall_64+0x2b/0x80
  entry_SYSCALL_64_after_hwframe+0x46/0xb0

 Freed by task 5680:
  kasan_save_stack+0x1e/0x40
  kasan_set_track+0x21/0x30
  kasan_set_free_info+0x20/0x30
  ____kasan_slab_free+0x144/0x1b0
  slab_free_freelist_hook+0xab/0x180
  kmem_cache_free+0x1f1/0x410
  xfs_rud_item_release+0x33/0x80 [xfs]
  xfs_trans_free_items+0xc3/0x220 [xfs]
  xfs_trans_cancel+0x1fa/0x590 [xfs]
  xfs_rui_item_recover+0x913/0xd60 [xfs]
  xlog_recover_process_intents+0x24e/0xae0 [xfs]
  xlog_recover_finish+0x7d/0x970 [xfs]
  xfs_log_mount_finish+0x2d7/0x5d0 [xfs]
  xfs_mountfs+0x11d4/0x1d10 [xfs]
  xfs_fs_fill_super+0x13d5/0x1a80 [xfs]
  get_tree_bdev+0x3da/0x6e0
  vfs_get_tree+0x7d/0x240
  path_mount+0xdd3/0x17d0
  __x64_sys_mount+0x1fa/0x270
  do_syscall_64+0x2b/0x80
  entry_SYSCALL_64_after_hwframe+0x46/0xb0

 The buggy address belongs to the object at ffff88804391b300
  which belongs to the cache xfs_rui_item of size 688
 The buggy address is located 96 bytes inside of
  688-byte region [ffff88804391b300, ffff88804391b5b0)

 The buggy address belongs to the physical page:
 page:ffffea00010e4600 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888043919320 pfn:0x43918
 head:ffffea00010e4600 order:2 compound_mapcount:0 compound_pincount:0
 flags: 0x4fff80000010200(slab|head|node=1|zone=1|lastcpupid=0xfff)
 raw: 04fff80000010200 0000000000000000 dead000000000122 ffff88807f0eadc0
 raw: ffff888043919320 0000000080140010 00000001ffffffff 0000000000000000
 page dumped because: kasan: bad access detected

 Memory state around the buggy address:
  ffff88804391b200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
  ffff88804391b280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 >ffff88804391b300: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                        ^
  ffff88804391b380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
  ffff88804391b400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ==================================================================

The test fuzzes an rmap btree block and starts writer threads to induce
a filesystem shutdown on the corrupt block.  When the filesystem is
remounted, recovery will try to replay the committed rmap intent item,
but the corruption problem causes the recovery transaction to fail.
Cancelling the transaction frees the RUD, which frees the RUI that we
recovered.

When we return to xlog_recover_process_intents, @lip is now a dangling
pointer, and we cannot use it to find the iop_recover method for the
tracepoint.  Hence we must store the item ops before calling
->iop_recover if we want to give it to the tracepoint so that the trace
data will tell us exactly which intent item failed.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2022-10-18 14:39:29 -07:00
Jason A. Donenfeld
a251c17aa5 treewide: use get_random_u32() when possible
The prandom_u32() function has been a deprecated inline wrapper around
get_random_u32() for several releases now, and compiles down to the
exact same code. Replace the deprecated wrapper with a direct call to
the real function. The same also applies to get_random_int(), which is
just a wrapper around get_random_u32(). This was done as a basic find
and replace.

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Yury Norov <yury.norov@gmail.com>
Reviewed-by: Jan Kara <jack@suse.cz> # for ext4
Acked-by: Toke Høiland-Jørgensen <toke@toke.dk> # for sch_cake
Acked-by: Chuck Lever <chuck.lever@oracle.com> # for nfsd
Acked-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> # for thunderbolt
Acked-by: Darrick J. Wong <djwong@kernel.org> # for xfs
Acked-by: Helge Deller <deller@gmx.de> # for parisc
Acked-by: Heiko Carstens <hca@linux.ibm.com> # for s390
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2022-10-11 17:42:58 -06:00
Jason A. Donenfeld
81895a65ec treewide: use prandom_u32_max() when possible, part 1
Rather than incurring a division or requesting too many random bytes for
the given range, use the prandom_u32_max() function, which only takes
the minimum required bytes from the RNG and avoids divisions. This was
done mechanically with this coccinelle script:

@basic@
expression E;
type T;
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
typedef u64;
@@
(
- ((T)get_random_u32() % (E))
+ prandom_u32_max(E)
|
- ((T)get_random_u32() & ((E) - 1))
+ prandom_u32_max(E * XXX_MAKE_SURE_E_IS_POW2)
|
- ((u64)(E) * get_random_u32() >> 32)
+ prandom_u32_max(E)
|
- ((T)get_random_u32() & ~PAGE_MASK)
+ prandom_u32_max(PAGE_SIZE)
)

@multi_line@
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
identifier RAND;
expression E;
@@

-       RAND = get_random_u32();
        ... when != RAND
-       RAND %= (E);
+       RAND = prandom_u32_max(E);

// Find a potential literal
@literal_mask@
expression LITERAL;
type T;
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
position p;
@@

        ((T)get_random_u32()@p & (LITERAL))

// Add one to the literal.
@script:python add_one@
literal << literal_mask.LITERAL;
RESULT;
@@

value = None
if literal.startswith('0x'):
        value = int(literal, 16)
elif literal[0] in '123456789':
        value = int(literal, 10)
if value is None:
        print("I don't know how to handle %s" % (literal))
        cocci.include_match(False)
elif value == 2**32 - 1 or value == 2**31 - 1 or value == 2**24 - 1 or value == 2**16 - 1 or value == 2**8 - 1:
        print("Skipping 0x%x for cleanup elsewhere" % (value))
        cocci.include_match(False)
elif value & (value + 1) != 0:
        print("Skipping 0x%x because it's not a power of two minus one" % (value))
        cocci.include_match(False)
elif literal.startswith('0x'):
        coccinelle.RESULT = cocci.make_expr("0x%x" % (value + 1))
else:
        coccinelle.RESULT = cocci.make_expr("%d" % (value + 1))

// Replace the literal mask with the calculated result.
@plus_one@
expression literal_mask.LITERAL;
position literal_mask.p;
expression add_one.RESULT;
identifier FUNC;
@@

-       (FUNC()@p & (LITERAL))
+       prandom_u32_max(RESULT)

@collapse_ret@
type T;
identifier VAR;
expression E;
@@

 {
-       T VAR;
-       VAR = (E);
-       return VAR;
+       return E;
 }

@drop_var@
type T;
identifier VAR;
@@

 {
-       T VAR;
        ... when != VAR
 }

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Yury Norov <yury.norov@gmail.com>
Reviewed-by: KP Singh <kpsingh@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz> # for ext4 and sbitmap
Reviewed-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com> # for drbd
Acked-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Heiko Carstens <hca@linux.ibm.com> # for s390
Acked-by: Ulf Hansson <ulf.hansson@linaro.org> # for mmc
Acked-by: Darrick J. Wong <djwong@kernel.org> # for xfs
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2022-10-11 17:42:55 -06:00
Linus Torvalds
60bb8154d1 xfs: changes for 6.1-rc1
This update contains:
 - fixes for filesystem shutdown procedure during a DAX memory
   failure notification
 - bug fixes
 - logic cleanups
 - log message cleanups
 - updates to use vfs{g,u}id_t helpers where appropriate
 
 Signed-off-by: Dave Chinner <david@fromorbit.com>
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Merge tag 'xfs-6.1-for-linus' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux

Pull xfs updates from Dave Chinner:
 "There are relatively few updates this cycle; half the cycle was eaten
  by a grue, the other half was eaten by a tricky data corruption issue
  that I still haven't entirely solved.

  Hence there's no major changes in this cycle and it's largely just
  minor cleanups and small bug fixes:

   - fixes for filesystem shutdown procedure during a DAX memory failure
     notification

   - bug fixes

   - logic cleanups

   - log message cleanups

   - updates to use vfs{g,u}id_t helpers where appropriate"

* tag 'xfs-6.1-for-linus' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  xfs: on memory failure, only shut down fs after scanning all mappings
  xfs: rearrange the logic and remove the broken comment for xfs_dir2_isxx
  xfs: trim the mapp array accordingly in xfs_da_grow_inode_int
  xfs: do not need to check return value of xlog_kvmalloc()
  xfs: port to vfs{g,u}id_t and associated helpers
  xfs: remove xfs_setattr_time() declaration
  xfs: Remove the unneeded result variable
  xfs: missing space in xfs trace log
  xfs: simplify if-else condition in xfs_reflink_trim_around_shared
  xfs: simplify if-else condition in xfs_validate_new_dalign
  xfs: replace unnecessary seq_printf with seq_puts
  xfs: clean up "%Ld/%Lu" which doesn't meet C standard
  xfs: remove redundant else for clean code
  xfs: remove the redundant word in comment
2022-10-10 20:32:10 -07:00
Linus Torvalds
f721d24e5d tmpfile API change
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Merge tag 'pull-tmpfile' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull vfs tmpfile updates from Al Viro:
 "Miklos' ->tmpfile() signature change; pass an unopened struct file to
  it, let it open the damn thing. Allows to add tmpfile support to FUSE"

* tag 'pull-tmpfile' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  fuse: implement ->tmpfile()
  vfs: open inside ->tmpfile()
  vfs: move open right after ->tmpfile()
  vfs: make vfs_tmpfile() static
  ovl: use vfs_tmpfile_open() helper
  cachefiles: use vfs_tmpfile_open() helper
  cachefiles: only pass inode to *mark_inode_inuse() helpers
  cachefiles: tmpfile error handling cleanup
  hugetlbfs: cleanup mknod and tmpfile
  vfs: add vfs_tmpfile_open() helper
2022-10-10 19:45:17 -07:00
Linus Torvalds
30c999937f Scheduler changes for v6.1:
- Debuggability:
 
      - Change most occurances of BUG_ON() to WARN_ON_ONCE()
 
      - Reorganize & fix TASK_ state comparisons, turn it into a bitmap
 
      - Update/fix misc scheduler debugging facilities
 
  - Load-balancing & regular scheduling:
 
      - Improve the behavior of the scheduler in presence of lot of
        SCHED_IDLE tasks - in particular they should not impact other
        scheduling classes.
 
      - Optimize task load tracking, cleanups & fixes
 
      - Clean up & simplify misc load-balancing code
 
  - Freezer:
 
      - Rewrite the core freezer to behave better wrt thawing and be simpler
        in general, by replacing PF_FROZEN with TASK_FROZEN & fixing/adjusting
        all the fallout.
 
  - Deadline scheduler:
 
      - Fix the DL capacity-aware code
 
      - Factor out dl_task_is_earliest_deadline() & replenish_dl_new_period()
 
      - Relax/optimize locking in task_non_contending()
 
  - Cleanups:
 
      - Factor out the update_current_exec_runtime() helper
 
      - Various cleanups, simplifications
 
 Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'sched-core-2022-10-07' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull scheduler updates from Ingo Molnar:
 "Debuggability:

   - Change most occurances of BUG_ON() to WARN_ON_ONCE()

   - Reorganize & fix TASK_ state comparisons, turn it into a bitmap

   - Update/fix misc scheduler debugging facilities

  Load-balancing & regular scheduling:

   - Improve the behavior of the scheduler in presence of lot of
     SCHED_IDLE tasks - in particular they should not impact other
     scheduling classes.

   - Optimize task load tracking, cleanups & fixes

   - Clean up & simplify misc load-balancing code

  Freezer:

   - Rewrite the core freezer to behave better wrt thawing and be
     simpler in general, by replacing PF_FROZEN with TASK_FROZEN &
     fixing/adjusting all the fallout.

  Deadline scheduler:

   - Fix the DL capacity-aware code

   - Factor out dl_task_is_earliest_deadline() &
     replenish_dl_new_period()

   - Relax/optimize locking in task_non_contending()

  Cleanups:

   - Factor out the update_current_exec_runtime() helper

   - Various cleanups, simplifications"

* tag 'sched-core-2022-10-07' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (41 commits)
  sched: Fix more TASK_state comparisons
  sched: Fix TASK_state comparisons
  sched/fair: Move call to list_last_entry() in detach_tasks
  sched/fair: Cleanup loop_max and loop_break
  sched/fair: Make sure to try to detach at least one movable task
  sched: Show PF_flag holes
  freezer,sched: Rewrite core freezer logic
  sched: Widen TAKS_state literals
  sched/wait: Add wait_event_state()
  sched/completion: Add wait_for_completion_state()
  sched: Add TASK_ANY for wait_task_inactive()
  sched: Change wait_task_inactive()s match_state
  freezer,umh: Clean up freezer/initrd interaction
  freezer: Have {,un}lock_system_sleep() save/restore flags
  sched: Rename task_running() to task_on_cpu()
  sched/fair: Cleanup for SIS_PROP
  sched/fair: Default to false in test_idle_cores()
  sched/fair: Remove useless check in select_idle_core()
  sched/fair: Avoid double search on same cpu
  sched/fair: Remove redundant check in select_idle_smt()
  ...
2022-10-10 09:10:28 -07:00
Linus Torvalds
bc32a6330f The first two changes that involve files outside of fs/ext4:
- submit_bh() can never return an error, so change it to return void,
   and remove the unused checks from its callers
 
 - fix I_DIRTY_TIME handling so it will be set even if the inode
   already has I_DIRTY_INODE
 
 Performance:
 
 - Always enable i_version counter (as btrfs and xfs already do).
   Remove some uneeded i_version bumps to avoid unnecessary nfs cache
   invalidations.
 
 - Wake up journal waters in FIFO order, to avoid some journal users
   from not getting a journal handle for an unfairly long time.
 
 - In ext4_write_begin() allocate any necessary buffer heads before
   starting the journal handle.
 
 - Don't try to prefetch the block allocation bitmaps for a read-only
   file system.
 
 Bug Fixes:
 
 - Fix a number of fast commit bugs, including resources leaks and out
   of bound references in various error handling paths and/or if the fast
   commit log is corrupted.
 
 - Avoid stopping the online resize early when expanding a file system
   which is less than 16TiB to a size greater than 16TiB.
 
 - Fix apparent metadata corruption caused by a race with a metadata
   buffer head getting migrated while it was trying to be read.
 
 - Mark the lazy initialization thread freezable to prevent suspend
   failures.
 
 - Other miscellaneous bug fixes.
 
 Cleanups:
 
 - Break up the incredibly long ext4_full_super() function by
   refactoring to move code into more understandable, smaller
   functions.
 
 - Remove the deprecated (and ignored) noacl and nouser_attr mount
   option.
 
 - Factor out some common code in fast commit handling.
 
 - Other miscellaneous cleanups.
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Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

Pull ext4 updates from Ted Ts'o:
 "The first two changes involve files outside of fs/ext4:

   - submit_bh() can never return an error, so change it to return void,
     and remove the unused checks from its callers

   - fix I_DIRTY_TIME handling so it will be set even if the inode
     already has I_DIRTY_INODE

  Performance:

   - Always enable i_version counter (as btrfs and xfs already do).
     Remove some uneeded i_version bumps to avoid unnecessary nfs cache
     invalidations

   - Wake up journal waiters in FIFO order, to avoid some journal users
     from not getting a journal handle for an unfairly long time

   - In ext4_write_begin() allocate any necessary buffer heads before
     starting the journal handle

   - Don't try to prefetch the block allocation bitmaps for a read-only
     file system

  Bug Fixes:

   - Fix a number of fast commit bugs, including resources leaks and out
     of bound references in various error handling paths and/or if the
     fast commit log is corrupted

   - Avoid stopping the online resize early when expanding a file system
     which is less than 16TiB to a size greater than 16TiB

   - Fix apparent metadata corruption caused by a race with a metadata
     buffer head getting migrated while it was trying to be read

   - Mark the lazy initialization thread freezable to prevent suspend
     failures

   - Other miscellaneous bug fixes

  Cleanups:

   - Break up the incredibly long ext4_full_super() function by
     refactoring to move code into more understandable, smaller
     functions

   - Remove the deprecated (and ignored) noacl and nouser_attr mount
     option

   - Factor out some common code in fast commit handling

   - Other miscellaneous cleanups"

* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (53 commits)
  ext4: fix potential out of bound read in ext4_fc_replay_scan()
  ext4: factor out ext4_fc_get_tl()
  ext4: introduce EXT4_FC_TAG_BASE_LEN helper
  ext4: factor out ext4_free_ext_path()
  ext4: remove unnecessary drop path references in mext_check_coverage()
  ext4: update 'state->fc_regions_size' after successful memory allocation
  ext4: fix potential memory leak in ext4_fc_record_regions()
  ext4: fix potential memory leak in ext4_fc_record_modified_inode()
  ext4: remove redundant checking in ext4_ioctl_checkpoint
  jbd2: add miss release buffer head in fc_do_one_pass()
  ext4: move DIOREAD_NOLOCK setting to ext4_set_def_opts()
  ext4: remove useless local variable 'blocksize'
  ext4: unify the ext4 super block loading operation
  ext4: factor out ext4_journal_data_mode_check()
  ext4: factor out ext4_load_and_init_journal()
  ext4: factor out ext4_group_desc_init() and ext4_group_desc_free()
  ext4: factor out ext4_geometry_check()
  ext4: factor out ext4_check_feature_compatibility()
  ext4: factor out ext4_init_metadata_csum()
  ext4: factor out ext4_encoding_init()
  ...
2022-10-06 17:45:53 -07:00
Linus Torvalds
7a3353c5c4 struct file-related stuff
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Merge tag 'pull-file' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull vfs file updates from Al Viro:
 "struct file-related stuff"

* tag 'pull-file' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  dma_buf_getfile(): don't bother with ->f_flags reassignments
  Change calling conventions for filldir_t
  locks: fix TOCTOU race when granting write lease
2022-10-06 17:13:18 -07:00
Darrick J. Wong
e033f40be2 xfs: on memory failure, only shut down fs after scanning all mappings
xfs_dax_failure_fn is used to scan the filesystem during a memory
failure event to look for memory mappings to revoke.  Unfortunately,
if it encounters an rmap record for filesystem metadata, it will
shut down the filesystem and the scan immediately.  This means that
we don't complete the mapping revocation scan and instead leave live
mappings to failed memory.  Fix the function to defer the shutdown
until after we've finished culling mappings.

While we're at it, add the usual "xfs_" prefix to struct
failure_info, and actually initialize mf_flags.

Fixes: 6f643c57d57c ("xfs: implement ->notify_failure() for XFS")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2022-10-04 16:40:01 +11:00
Shida Zhang
c098576f5f xfs: rearrange the logic and remove the broken comment for xfs_dir2_isxx
xfs_dir2_isleaf is used to see if the directory is a single-leaf
form directory instead, as commented right above the function.

Besides getting rid of the broken comment, we rearrange the logic by
converting everything over to standard formatting and conventions,
at the same time, to make it easier to understand and self documenting.

Signed-off-by: Shida Zhang <zhangshida@kylinos.cn>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2022-10-04 16:39:58 +11:00
Shida Zhang
44159659df xfs: trim the mapp array accordingly in xfs_da_grow_inode_int
Take a look at the for-loop in xfs_da_grow_inode_int:
======
for(){
        nmap = min(XFS_BMAP_MAX_NMAP, count);
        ...
        error = xfs_bmapi_write(...,&mapp[mapi], &nmap);//(..., $1, $2)
        ...
        mapi += nmap;
}
=====
where $1 stands for the start address of the array,
while $2 is used to indicate the size of the array.

The array $1 will advance by $nmap in each iteration after
the allocation of extents.
But the size $2 still remains unchanged, which is determined by
min(XFS_BMAP_MAX_NMAP, count).

It seems that it has forgotten to trim the mapp array after each
iteration, so change it.

Signed-off-by: Shida Zhang <zhangshida@kylinos.cn>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2022-10-04 16:39:42 +11:00
Linus Torvalds
725737e7c2 STATX_DIOALIGN for 6.1
Make statx() support reporting direct I/O (DIO) alignment information.
 This provides a generic interface for userspace programs to determine
 whether a file supports DIO, and if so with what alignment restrictions.
 Specifically, STATX_DIOALIGN works on block devices, and on regular
 files when their containing filesystem has implemented support.
 
 An interface like this has been requested for years, since the
 conditions for when DIO is supported in Linux have gotten increasingly
 complex over time.  Today, DIO support and alignment requirements can be
 affected by various filesystem features such as multi-device support,
 data journalling, inline data, encryption, verity, compression,
 checkpoint disabling, log-structured mode, etc.  Further complicating
 things, Linux v6.0 relaxed the traditional rule of DIO needing to be
 aligned to the block device's logical block size; now user buffers (but
 not file offsets) only need to be aligned to the DMA alignment.
 
 The approach of uplifting the XFS specific ioctl XFS_IOC_DIOINFO was
 discarded in favor of creating a clean new interface with statx().
 
 For more information, see the individual commits and the man page update
 https://lore.kernel.org/r/20220722074229.148925-1-ebiggers@kernel.org.
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Merge tag 'statx-dioalign-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/linux

Pull STATX_DIOALIGN support from Eric Biggers:
 "Make statx() support reporting direct I/O (DIO) alignment information.

  This provides a generic interface for userspace programs to determine
  whether a file supports DIO, and if so with what alignment
  restrictions. Specifically, STATX_DIOALIGN works on block devices, and
  on regular files when their containing filesystem has implemented
  support.

  An interface like this has been requested for years, since the
  conditions for when DIO is supported in Linux have gotten increasingly
  complex over time. Today, DIO support and alignment requirements can
  be affected by various filesystem features such as multi-device
  support, data journalling, inline data, encryption, verity,
  compression, checkpoint disabling, log-structured mode, etc.

  Further complicating things, Linux v6.0 relaxed the traditional rule
  of DIO needing to be aligned to the block device's logical block size;
  now user buffers (but not file offsets) only need to be aligned to the
  DMA alignment.

  The approach of uplifting the XFS specific ioctl XFS_IOC_DIOINFO was
  discarded in favor of creating a clean new interface with statx().

  For more information, see the individual commits and the man page
  update[1]"

Link: https://lore.kernel.org/r/20220722074229.148925-1-ebiggers@kernel.org [1]

* tag 'statx-dioalign-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/linux:
  xfs: support STATX_DIOALIGN
  f2fs: support STATX_DIOALIGN
  f2fs: simplify f2fs_force_buffered_io()
  f2fs: move f2fs_force_buffered_io() into file.c
  ext4: support STATX_DIOALIGN
  fscrypt: change fscrypt_dio_supported() to prepare for STATX_DIOALIGN
  vfs: support STATX_DIOALIGN on block devices
  statx: add direct I/O alignment information
2022-10-03 20:33:41 -07:00