51304 Commits

Author SHA1 Message Date
Bart Van Assche
c984f4d1d4 scsi: sysfs: Introduce sysfs_{un,}break_active_protection()
commit 2afc9166f79b8f6da5f347f48515215ceee4ae37 upstream.

Introduce these two functions and export them such that the next patch
can add calls to these functions from the SCSI core.

Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-05 09:26:41 +02:00
Kirill Tkhai
e8a3f3a036 fuse: Add missed unlock_page() to fuse_readpages_fill()
commit 109728ccc5933151c68d1106e4065478a487a323 upstream.

The above error path returns with page unlocked, so this place seems also
to behave the same.

Fixes: f8dbdf81821b ("fuse: rework fuse_readpages()")
Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-05 09:26:38 +02:00
Miklos Szeredi
ff4a71855d fuse: Fix oops at process_init_reply()
commit e8f3bd773d22f488724dffb886a1618da85c2966 upstream.

syzbot is hitting NULL pointer dereference at process_init_reply().
This is because deactivate_locked_super() is called before response for
initial request is processed.

Fix this by aborting and waiting for all requests (including FUSE_INIT)
before resetting fc->sb.

Original patch by Tetsuo Handa <penguin-kernel@I-love.SKAURA.ne.jp>.

Reported-by: syzbot <syzbot+b62f08f4d5857755e3bc@syzkaller.appspotmail.com>
Fixes: e27c9d3877a0 ("fuse: fuse: add time_gran to INIT_OUT")
Cc: <stable@vger.kernel.org> # v3.19
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-05 09:26:38 +02:00
Miklos Szeredi
9732069238 fuse: umount should wait for all requests
commit b8f95e5d13f5f0191dcb4b9113113d241636e7cb upstream.

fuse_abort_conn() does not guarantee that all async requests have actually
finished aborting (i.e. their ->end() function is called).  This could
actually result in still used inodes after umount.

Add a helper to wait until all requests are fully done.  This is done by
looking at the "num_waiting" counter.  When this counter drops to zero, we
can be sure that no more requests are outstanding.

Fixes: 0d8e84b0432b ("fuse: simplify request abort")
Cc: <stable@vger.kernel.org> # v4.2
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-05 09:26:38 +02:00
Miklos Szeredi
fc17d7519e fuse: fix unlocked access to processing queue
commit 45ff350bbd9d0f0977ff270a0d427c71520c0c37 upstream.

fuse_dev_release() assumes that it's the only one referencing the
fpq->processing list, but that's not true, since fuse_abort_conn() can be
doing the same without any serialization between the two.

Fixes: c3696046beb3 ("fuse: separate pqueue for clones")
Cc: <stable@vger.kernel.org> # v4.2
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-05 09:26:38 +02:00
Miklos Szeredi
cfb6eca6e4 fuse: fix double request_end()
commit 87114373ea507895a62afb10d2910bd9adac35a8 upstream.

Refcounting of request is broken when fuse_abort_conn() is called and
request is on the fpq->io list:

 - ref is taken too late
 - then it is not dropped

Fixes: 0d8e84b0432b ("fuse: simplify request abort")
Cc: <stable@vger.kernel.org> # v4.2
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-05 09:26:38 +02:00
Miklos Szeredi
7d39267444 fuse: fix initial parallel dirops
commit 63576c13bd17848376c8ba4a98f5d5151140c4ac upstream.

If parallel dirops are enabled in FUSE_INIT reply, then first operation may
leave fi->mutex held.

Reported-by: syzbot <syzbot+3f7b29af1baa9d0a55be@syzkaller.appspotmail.com>
Fixes: 5c672ab3f0ee ("fuse: serialize dirops by default")
Cc: <stable@vger.kernel.org> # v4.7
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-05 09:26:38 +02:00
Andrey Ryabinin
eaebcf902a fuse: Don't access pipe->buffers without pipe_lock()
commit a2477b0e67c52f4364a47c3ad70902bc2a61bd4c upstream.

fuse_dev_splice_write() reads pipe->buffers to determine the size of
'bufs' array before taking the pipe_lock(). This is not safe as
another thread might change the 'pipe->buffers' between the allocation
and taking the pipe_lock(). So we end up with too small 'bufs' array.

Move the bufs allocations inside pipe_lock()/pipe_unlock() to fix this.

Fixes: dd3bb14f44a6 ("fuse: support splice() writing to fuse device")
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: <stable@vger.kernel.org> # v2.6.35
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-05 09:26:37 +02:00
Eric Sandeen
509c0cdfb4 ext4: reset error code in ext4_find_entry in fallback
commit f39b3f45dbcb0343822cce31ea7636ad66e60bc2 upstream.

When ext4_find_entry() falls back to "searching the old fashioned
way" due to a corrupt dx dir, it needs to reset the error code
to NULL so that the nonstandard ERR_BAD_DX_DIR code isn't returned
to userspace.

https://bugzilla.kernel.org/show_bug.cgi?id=199947

Reported-by: Anatoly Trosinenko <anatoly.trosinenko@yandex.com>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-05 09:26:36 +02:00
Arnd Bergmann
5043e05dd5 ext4: sysfs: print ext4_super_block fields as little-endian
commit a4d2aadca184ece182418950d45ba4ffc7b652d2 upstream.

While working on extended rand for last_error/first_error timestamps,
I noticed that the endianess is wrong; we access the little-endian
fields in struct ext4_super_block as native-endian when we print them.

This adds a special case in ext4_attr_show() and ext4_attr_store()
to byteswap the superblock fields if needed.

In older kernels, this code was part of super.c, it got moved to
sysfs.c in linux-4.4.

Cc: stable@vger.kernel.org
Fixes: 52c198c6820f ("ext4: add sysfs entry showing whether the fs contains errors")
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-05 09:26:36 +02:00
Theodore Ts'o
7773a6d948 ext4: check for NUL characters in extended attribute's name
commit 7d95178c77014dbd8dce36ee40bbbc5e6c121ff5 upstream.

Extended attribute names are defined to be NUL-terminated, so the name
must not contain a NUL character.  This is important because there are
places when remove extended attribute, the code uses strlen to
determine the length of the entry.  That should probably be fixed at
some point, but code is currently really messy, so the simplest fix
for now is to simply validate that the extended attributes are sane.

https://bugzilla.kernel.org/show_bug.cgi?id=200401

Reported-by: Wen Xu <wen.xu@gatech.edu>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-05 09:26:36 +02:00
Josef Bacik
f91ca31f53 Btrfs: fix btrfs_write_inode vs delayed iput deadlock
commit 3c4276936f6fbe52884b4ea4e6cc120b890a0f9f upstream.

We recently ran into the following deadlock involving
btrfs_write_inode():

[  +0.005066]  __schedule+0x38e/0x8c0
[  +0.007144]  schedule+0x36/0x80
[  +0.006447]  bit_wait+0x11/0x60
[  +0.006446]  __wait_on_bit+0xbe/0x110
[  +0.007487]  ? bit_wait_io+0x60/0x60
[  +0.007319]  __inode_wait_for_writeback+0x96/0xc0
[  +0.009568]  ? autoremove_wake_function+0x40/0x40
[  +0.009565]  inode_wait_for_writeback+0x21/0x30
[  +0.009224]  evict+0xb0/0x190
[  +0.006099]  iput+0x1a8/0x210
[  +0.006103]  btrfs_run_delayed_iputs+0x73/0xc0
[  +0.009047]  btrfs_commit_transaction+0x799/0x8c0
[  +0.009567]  btrfs_write_inode+0x81/0xb0
[  +0.008008]  __writeback_single_inode+0x267/0x320
[  +0.009569]  writeback_sb_inodes+0x25b/0x4e0
[  +0.008702]  wb_writeback+0x102/0x2d0
[  +0.007487]  wb_workfn+0xa4/0x310
[  +0.006794]  ? wb_workfn+0xa4/0x310
[  +0.007143]  process_one_work+0x150/0x410
[  +0.008179]  worker_thread+0x6d/0x520
[  +0.007490]  kthread+0x12c/0x160
[  +0.006620]  ? put_pwq_unlocked+0x80/0x80
[  +0.008185]  ? kthread_park+0xa0/0xa0
[  +0.007484]  ? do_syscall_64+0x53/0x150
[  +0.007837]  ret_from_fork+0x29/0x40

Writeback calls:

btrfs_write_inode
  btrfs_commit_transaction
    btrfs_run_delayed_iputs

If iput() is called on that same inode, evict() will wait for writeback
forever.

btrfs_write_inode() was originally added way back in 4730a4bc5bf3
("btrfs_dirty_inode") to support O_SYNC writes. However, ->write_inode()
hasn't been used for O_SYNC since 148f948ba877 ("vfs: Introduce new
helpers for syncing after writing to O_SYNC file or IS_SYNC inode"), so
btrfs_write_inode() is actually unnecessary (and leads to a bunch of
unnecessary commits). Get rid of it, which also gets rid of the
deadlock.

CC: stable@vger.kernel.org # 3.2+
Signed-off-by: Josef Bacik <jbacik@fb.com>
[Omar: new commit message]
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-05 09:26:34 +02:00
Josef Bacik
e7457f97d2 btrfs: don't leak ret from do_chunk_alloc
commit 4559b0a71749c442d34f7cfb9e72c9e58db83948 upstream.

If we're trying to make a data reservation and we have to allocate a
data chunk we could leak ret == 1, as do_chunk_alloc() will return 1 if
it allocated a chunk.  Since the end of the function is the success path
just return 0.

CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-05 09:26:33 +02:00
Ethan Lien
770025cc4b btrfs: use correct compare function of dirty_metadata_bytes
commit d814a49198eafa6163698bdd93961302f3a877a4 upstream.

We use customized, nodesize batch value to update dirty_metadata_bytes.
We should also use batch version of compare function or we will easily
goto fast path and get false result from percpu_counter_compare().

Fixes: e2d845211eda ("Btrfs: use percpu counter for dirty metadata count")
CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Ethan Lien <ethanlien@synology.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-05 09:26:33 +02:00
Steve French
758f55f918 smb3: fill in statfs fsid and correct namelen
commit 21ba3845b59c733a79ed4fe1c4f3732e7ece9df7 upstream.

Fil in the correct namelen (typically 255 not 4096) in the
statfs response and also fill in a reasonably unique fsid
(in this case taken from the volume id, and the creation time
of the volume).

In the case of the POSIX statfs all fields are now filled in,
and in the case of non-POSIX mounts, all fields are filled
in which can be.

Signed-off-by: Steve French <stfrench@gmail.com>
CC: Stable <stable@vger.kernel.org>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-05 09:26:33 +02:00
Steve French
66913d23ee smb3: don't request leases in symlink creation and query
commit 22783155f4bf956c346a81624ec9258930a6fe06 upstream.

Fixes problem pointed out by Pavel in discussions about commit
729c0c9dd55204f0c9a823ac8a7bfa83d36c7e78

Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
CC: Stable <stable@vger.kernel.org> # 3.18.x+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-05 09:26:33 +02:00
Steve French
be1210c775 smb3: Do not send SMB3 SET_INFO if nothing changed
commit fd09b7d3b352105f08b8e02f7afecf7e816380ef upstream.

An earlier commit had a typo which prevented the
optimization from working:

commit 18dd8e1a65dd ("Do not send SMB3 SET_INFO request if nothing is changing")

Thank you to Metze for noticing this.  Also clear a
reserved field in the FILE_BASIC_INFO struct we send
that should be zero (all the other fields in that
struct were set or cleared explicitly already in
cifs_set_file_info).

Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
CC: Stable <stable@vger.kernel.org> # 4.9.x+
Reported-by: Stefan Metzmacher <metze@samba.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-05 09:26:33 +02:00
Steve French
82a856f527 smb3: enumerating snapshots was leaving part of the data off end
commit e02789a53d71334b067ad72eee5d4e88a0158083 upstream.

When enumerating snapshots, the last few bytes of the final
snapshot could be left off since we were miscalculating the
length returned (leaving off the sizeof struct SRV_SNAPSHOT_ARRAY)
See MS-SMB2 section 2.2.32.2. In addition fixup the length used
to allow smaller buffer to be passed in, in order to allow
returning the size of the whole snapshot array more easily.

Sample userspace output with a kernel patched with this
(mounted to a Windows volume with two snapshots).
Before this patch, the second snapshot would be missing a
few bytes at the end.

~/cifs-2.6# ~/enum-snapshots /mnt/file
press enter to issue the ioctl to retrieve snapshot information ...

size of snapshot array = 102
Num snapshots: 2 Num returned: 2 Array Size: 102

Snapshot 0:@GMT-2018.06.30-19.34.17
Snapshot 1:@GMT-2018.06.30-19.33.37

CC: Stable <stable@vger.kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-05 09:26:33 +02:00
Nicholas Mc Guire
d5f2790a7a cifs: check kmalloc before use
commit 126c97f4d0d1b5b956e8b0740c81a2b2a2ae548c upstream.

The kmalloc was not being checked - if it fails issue a warning
and return -ENOMEM to the caller.

Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
Fixes: b8da344b74c8 ("cifs: dynamic allocation of ntlmssp blob")
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
cc: Stable <stable@vger.kernel.org>`
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-05 09:26:33 +02:00
Steve French
cba34b9407 cifs: add missing debug entries for kconfig options
commit 950132afd59385caf6e2b84e5235d069fa10681d upstream.

/proc/fs/cifs/DebugData displays the features (Kconfig options)
used to build cifs.ko but it was missing some, and needed comma
separator.  These can be useful in debugging certain problems
so we know which optional features were enabled in the user's build.
Also clarify them, by making them more closely match the
corresponding CONFIG_CIFS_* parm.

Old format:
Features: dfs fscache posix spnego xattr acl

New format:
Features: DFS,FSCACHE,SMB_DIRECT,STATS,DEBUG2,ALLOW_INSECURE_LEGACY,CIFS_POSIX,UPCALL(SPNEGO),XATTR,ACL

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: Paulo Alcantara <palcantara@suse.de>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-05 09:26:33 +02:00
Phillip Lougher
28013eecf6 Squashfs: Compute expected length from inode size rather than block length
[ Upstream commit a3f94cb99a854fa381fe7fadd97c4f61633717a5 ]

Previously in squashfs_readpage() when copying data into the page
cache, it used the length of the datablock read from the filesystem
(after decompression).  However, if the filesystem has been corrupted
this data block may be short, which will leave pages unfilled.

The fix for this is to compute the expected number of bytes to copy
from the inode size, and use this to detect if the block is short.

Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk>
Tested-by: Willy Tarreau <w@1wt.eu>
Cc: Анатолий Тросиненко <anatoly.trosinenko@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-05 09:26:32 +02:00
Linus Torvalds
8babbc02f8 squashfs metadata 2: electric boogaloo
[ Upstream commit cdbb65c4c7ead680ebe54f4f0d486e2847a500ea ]

Anatoly continues to find issues with fuzzed squashfs images.

This time, corrupt, missing, or undersized data for the page filling
wasn't checked for, because the squashfs_{copy,read}_cache() functions
did the squashfs_copy_data() call without checking the resulting data
size.

Which could result in the page cache pages being incompletely filled in,
and no error indication to the user space reading garbage data.

So make a helper function for the "fill in pages" case, because the
exact same incomplete sequence existed in two places.

[ I should have made a squashfs branch for these things, but I didn't
  intend to start doing them in the first place.

  My historical connection through cramfs is why I got into looking at
  these issues at all, and every time I (continue to) think it's a
  one-off.

  Because _this_ time is always the last time. Right?   - Linus ]

Reported-by: Anatoly Trosinenko <anatoly.trosinenko@gmail.com>
Tested-by: Willy Tarreau <w@1wt.eu>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Phillip Lougher <phillip@squashfs.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-05 09:26:31 +02:00
Kiran Kumar Modukuri
2c69b03004 cachefiles: Wait rather than BUG'ing on "Unexpected object collision"
[ Upstream commit c2412ac45a8f8f1cd582723c1a139608694d410d ]

If we meet a conflicting object that is marked FSCACHE_OBJECT_IS_LIVE in
the active object tree, we have been emitting a BUG after logging
information about it and the new object.

Instead, we should wait for the CACHEFILES_OBJECT_ACTIVE flag to be cleared
on the old object (or return an error).  The ACTIVE flag should be cleared
after it has been removed from the active object tree.  A timeout of 60s is
used in the wait, so we shouldn't be able to get stuck there.

Fixes: 9ae326a69004 ("CacheFiles: A cache that backs onto a mounted filesystem")
Signed-off-by: Kiran Kumar Modukuri <kiran.modukuri@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-05 09:26:29 +02:00
Kiran Kumar Modukuri
4029dd9fc4 cachefiles: Fix refcounting bug in backing-file read monitoring
[ Upstream commit 934140ab028713a61de8bca58c05332416d037d1 ]

cachefiles_read_waiter() has the right to access a 'monitor' object by
virtue of being called under the waitqueue lock for one of the pages in its
purview.  However, it has no ref on that monitor object or on the
associated operation.

What it is allowed to do is to move the monitor object to the operation's
to_do list, but once it drops the work_lock, it's actually no longer
permitted to access that object.  However, it is trying to enqueue the
retrieval operation for processing - but it can only do this via a pointer
in the monitor object, something it shouldn't be doing.

If it doesn't enqueue the operation, the operation may not get processed.
If the order is flipped so that the enqueue is first, then it's possible
for the work processor to look at the to_do list before the monitor is
enqueued upon it.

Fix this by getting a ref on the operation so that we can trust that it
will still be there once we've added the monitor to the to_do list and
dropped the work_lock.  The op can then be enqueued after the lock is
dropped.

The bug can manifest in one of a couple of ways.  The first manifestation
looks like:

 FS-Cache:
 FS-Cache: Assertion failed
 FS-Cache: 6 == 5 is false
 ------------[ cut here ]------------
 kernel BUG at fs/fscache/operation.c:494!
 RIP: 0010:fscache_put_operation+0x1e3/0x1f0
 ...
 fscache_op_work_func+0x26/0x50
 process_one_work+0x131/0x290
 worker_thread+0x45/0x360
 kthread+0xf8/0x130
 ? create_worker+0x190/0x190
 ? kthread_cancel_work_sync+0x10/0x10
 ret_from_fork+0x1f/0x30

This is due to the operation being in the DEAD state (6) rather than
INITIALISED, COMPLETE or CANCELLED (5) because it's already passed through
fscache_put_operation().

The bug can also manifest like the following:

 kernel BUG at fs/fscache/operation.c:69!
 ...
    [exception RIP: fscache_enqueue_operation+246]
 ...
 #7 [ffff883fff083c10] fscache_enqueue_operation at ffffffffa0b793c6
 #8 [ffff883fff083c28] cachefiles_read_waiter at ffffffffa0b15a48
 #9 [ffff883fff083c48] __wake_up_common at ffffffff810af028

I'm not entirely certain as to which is line 69 in Lei's kernel, so I'm not
entirely clear which assertion failed.

Fixes: 9ae326a69004 ("CacheFiles: A cache that backs onto a mounted filesystem")
Reported-by: Lei Xue <carmark.dlut@gmail.com>
Reported-by: Vegard Nossum <vegard.nossum@gmail.com>
Reported-by: Anthony DeRobertis <aderobertis@metrics.net>
Reported-by: NeilBrown <neilb@suse.com>
Reported-by: Daniel Axtens <dja@axtens.net>
Reported-by: Kiran Kumar Modukuri <kiran.modukuri@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-05 09:26:29 +02:00
Kiran Kumar Modukuri
819b476c21 fscache: Allow cancelled operations to be enqueued
[ Upstream commit d0eb06afe712b7b103b6361f40a9a0c638524669 ]

Alter the state-check assertion in fscache_enqueue_operation() to allow
cancelled operations to be given processing time so they can be cleaned up.

Also fix a debugging statement that was requiring such operations to have
an object assigned.

Fixes: 9ae326a69004 ("CacheFiles: A cache that backs onto a mounted filesystem")
Reported-by: Kiran Kumar Modukuri <kiran.modukuri@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-05 09:26:29 +02:00
Theodore Ts'o
147b89c421 ext4: clear mmp sequence number when remounting read-only
[ Upstream commit 2dca60d98e241bea686004168f85208f215fc697 ]

Previously, when an MMP-protected file system is remounted read-only,
the kmmpd thread would exit the next time it woke up (a few seconds
later), without resetting the MMP sequence number back to
EXT4_MMP_SEQ_CLEAN.

Fix this by explicitly killing the MMP thread when the file system is
remounted read-only.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-05 09:26:24 +02:00
Jann Horn
ef3cf941e0 reiserfs: fix broken xattr handling (heap corruption, bad retval)
commit a13f085d111e90469faf2d9965eb39b11c114d7e upstream.

This fixes the following issues:

- When a buffer size is supplied to reiserfs_listxattr() such that each
  individual name fits, but the concatenation of all names doesn't fit,
  reiserfs_listxattr() overflows the supplied buffer.  This leads to a
  kernel heap overflow (verified using KASAN) followed by an out-of-bounds
  usercopy and is therefore a security bug.

- When a buffer size is supplied to reiserfs_listxattr() such that a
  name doesn't fit, -ERANGE should be returned.  But reiserfs instead just
  truncates the list of names; I have verified that if the only xattr on a
  file has a longer name than the supplied buffer length, listxattr()
  incorrectly returns zero.

With my patch applied, -ERANGE is returned in both cases and the memory
corruption doesn't happen anymore.

Credit for making me clean this code up a bit goes to Al Viro, who pointed
out that the ->actor calling convention is suboptimal and should be
changed.

Link: http://lkml.kernel.org/r/20180802151539.5373-1-jannh@google.com
Fixes: 48b32a3553a5 ("reiserfs: use generic xattr handlers")
Signed-off-by: Jann Horn <jannh@google.com>
Acked-by: Jeff Mahoney <jeffm@suse.com>
Cc: Eric Biggers <ebiggers@google.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-24 13:09:23 +02:00
Jaegeuk Kim
deebf1d61e f2fs: sanity check for total valid node blocks
commit 8a29c1260e24e7c9c6ab138aa0017558d8b28208 upstream.

This patch enhances sanity check for SIT entries.

syzbot hit the following crash on upstream commit
83beed7b2b26f232d782127792dd0cd4362fdc41 (Fri Apr 20 17:56:32 2018 +0000)
Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/evalenti/linux-soc-thermal
syzbot dashboard link: https://syzkaller.appspot.com/bug?extid=bf9253040425feb155ad

syzkaller reproducer: https://syzkaller.appspot.com/x/repro.syz?id=5692130282438656
Raw console output: https://syzkaller.appspot.com/x/log.txt?id=5095924598571008
Kernel config: https://syzkaller.appspot.com/x/.config?id=1808800213120130118
compiler: gcc (GCC) 8.0.1 20180413 (experimental)

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+bf9253040425feb155ad@syzkaller.appspotmail.com
It will help syzbot understand when the bug is fixed. See footer for details.
If you forward the report, please keep this part and the footer.

F2FS-fs (loop0): invalid crc value
F2FS-fs (loop0): Try to recover 1th superblock, ret: 0
F2FS-fs (loop0): Mounted with checkpoint version = d
F2FS-fs (loop0): Bitmap was wrongly cleared, blk:9740
------------[ cut here ]------------
kernel BUG at fs/f2fs/segment.c:1884!
invalid opcode: 0000 [#1] SMP KASAN
Dumping ftrace buffer:
   (ftrace buffer empty)
Modules linked in:
CPU: 1 PID: 4508 Comm: syz-executor0 Not tainted 4.17.0-rc1+ #10
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:update_sit_entry+0x1215/0x1590 fs/f2fs/segment.c:1882
RSP: 0018:ffff8801af526708 EFLAGS: 00010282
RAX: ffffed0035ea4cc0 RBX: ffff8801ad454f90 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff82eeb87e RDI: ffffed0035ea4cb6
RBP: ffff8801af526760 R08: ffff8801ad4a2480 R09: ffffed003b5e4f90
R10: ffffed003b5e4f90 R11: ffff8801daf27c87 R12: ffff8801adb8d380
R13: 0000000000000001 R14: 0000000000000008 R15: 00000000ffffffff
FS:  00000000014af940(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f06bc223000 CR3: 00000001adb02000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 allocate_data_block+0x66f/0x2050 fs/f2fs/segment.c:2663
 do_write_page+0x105/0x1b0 fs/f2fs/segment.c:2727
 write_node_page+0x129/0x350 fs/f2fs/segment.c:2770
 __write_node_page+0x7da/0x1370 fs/f2fs/node.c:1398
 sync_node_pages+0x18cf/0x1eb0 fs/f2fs/node.c:1652
 block_operations+0x429/0xa60 fs/f2fs/checkpoint.c:1088
 write_checkpoint+0x3ba/0x5380 fs/f2fs/checkpoint.c:1405
 f2fs_sync_fs+0x2fb/0x6a0 fs/f2fs/super.c:1077
 __sync_filesystem fs/sync.c:39 [inline]
 sync_filesystem+0x265/0x310 fs/sync.c:67
 generic_shutdown_super+0xd7/0x520 fs/super.c:429
 kill_block_super+0xa4/0x100 fs/super.c:1191
 kill_f2fs_super+0x9f/0xd0 fs/f2fs/super.c:3030
 deactivate_locked_super+0x97/0x100 fs/super.c:316
 deactivate_super+0x188/0x1b0 fs/super.c:347
 cleanup_mnt+0xbf/0x160 fs/namespace.c:1174
 __cleanup_mnt+0x16/0x20 fs/namespace.c:1181
 task_work_run+0x1e4/0x290 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:191 [inline]
 exit_to_usermode_loop+0x2bd/0x310 arch/x86/entry/common.c:166
 prepare_exit_to_usermode arch/x86/entry/common.c:196 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:265 [inline]
 do_syscall_64+0x6ac/0x800 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x457d97
RSP: 002b:00007ffd46f9c8e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000457d97
RDX: 00000000014b09a3 RSI: 0000000000000002 RDI: 00007ffd46f9da50
RBP: 00007ffd46f9da50 R08: 0000000000000000 R09: 0000000000000009
R10: 0000000000000005 R11: 0000000000000246 R12: 00000000014b0940
R13: 0000000000000000 R14: 0000000000000002 R15: 000000000000658e
RIP: update_sit_entry+0x1215/0x1590 fs/f2fs/segment.c:1882 RSP: ffff8801af526708
---[ end trace f498328bb02610a2 ]---

Reported-and-tested-by: syzbot+bf9253040425feb155ad@syzkaller.appspotmail.com
Reported-and-tested-by: syzbot+7d6d31d3bc702f566ce3@syzkaller.appspotmail.com
Reported-and-tested-by: syzbot+0a725420475916460f12@syzkaller.appspotmail.com
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-24 13:09:21 +02:00
Jaegeuk Kim
2ab95e71c8 f2fs: return error during fill_super
commit c39a1b348c4fe172729eff77c533dabc3c7cdaa7 upstream.

Let's avoid BUG_ON during fill_super, when on-disk was totall corrupted.

Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-24 13:09:21 +02:00
Qu Wenruo
fc9caa36d8 btrfs: scrub: Don't use inode page cache in scrub_handle_errored_block()
[ Upstream commit 665d4953cde6d9e75c62a07ec8f4f8fd7d396ade ]

In commit ac0b4145d662 ("btrfs: scrub: Don't use inode pages for device
replace") we removed the branch of copy_nocow_pages() to avoid
corruption for compressed nodatasum extents.

However above commit only solves the problem in scrub_extent(), if
during scrub_pages() we failed to read some pages,
sctx->no_io_error_seen will be non-zero and we go to fixup function
scrub_handle_errored_block().

In scrub_handle_errored_block(), for sctx without csum (no matter if
we're doing replace or scrub) we go to scrub_fixup_nodatasum() routine,
which does the similar thing with copy_nocow_pages(), but does it
without the extra check in copy_nocow_pages() routine.

So for test cases like btrfs/100, where we emulate read errors during
replace/scrub, we could corrupt compressed extent data again.

This patch will fix it just by avoiding any "optimization" for
nodatasum, just falls back to the normal fixup routine by try read from
any good copy.

This also solves WARN_ON() or dead lock caused by lame backref iteration
in scrub_fixup_nodatasum() routine.

The deadlock or WARN_ON() won't be triggered before commit ac0b4145d662
("btrfs: scrub: Don't use inode pages for device replace") since
copy_nocow_pages() have better locking and extra check for data extent,
and it's already doing the fixup work by try to read data from any good
copy, so it won't go scrub_fixup_nodatasum() anyway.

This patch disables the faulty code and will be removed completely in a
followup patch.

Fixes: ac0b4145d662 ("btrfs: scrub: Don't use inode pages for device replace")
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-24 13:09:18 +02:00
Yan, Zheng
77c967872e ceph: fix dentry leak in splice_dentry()
[ Upstream commit 8b8f53af1ed9df88a4c0fbfdf3db58f62060edf3 ]

In any case, d_splice_alias() does not drop reference of original
dentry.

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-24 13:09:07 +02:00
Trond Myklebust
586ae5694e pNFS: Always free the session slot on error in nfs4_layoutget_handle_exception
[ Upstream commit 2dbf8dffbf35fd8f611083b9d9fe74fdccf912a3 ]

Right now, we can call nfs_commit_inode() while holding the session slot,
which could lead to NFSv4 deadlocks. Ensure we only keep the slot if
the server returned a layout that we have to process.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-24 13:09:01 +02:00
Jeremy Cline
4bc32484df ext4: fix spectre gadget in ext4_mb_regular_allocator()
commit 1a5d5e5d51e75a5bca67dadbcea8c841934b7b85 upstream.

'ac->ac_g_ex.fe_len' is a user-controlled value which is used in the
derivation of 'ac->ac_2order'. 'ac->ac_2order', in turn, is used to
index arrays which makes it a potential spectre gadget. Fix this by
sanitizing the value assigned to 'ac->ac2_order'.  This covers the
following accesses found with the help of smatch:

* fs/ext4/mballoc.c:1896 ext4_mb_simple_scan_group() warn: potential
  spectre issue 'grp->bb_counters' [w] (local cap)

* fs/ext4/mballoc.c:445 mb_find_buddy() warn: potential spectre issue
  'EXT4_SB(e4b->bd_sb)->s_mb_offsets' [r] (local cap)

* fs/ext4/mballoc.c:446 mb_find_buddy() warn: potential spectre issue
  'EXT4_SB(e4b->bd_sb)->s_mb_maxs' [r] (local cap)

Suggested-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Jeremy Cline <jcline@redhat.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-24 13:08:55 +02:00
Al Viro
e5751c8440 fix __legitimize_mnt()/mntput() race
commit 119e1ef80ecfe0d1deb6378d4ab41f5b71519de1 upstream.

__legitimize_mnt() has two problems - one is that in case of success
the check of mount_lock is not ordered wrt preceding increment of
refcount, making it possible to have successful __legitimize_mnt()
on one CPU just before the otherwise final mntpu() on another,
with __legitimize_mnt() not seeing mntput() taking the lock and
mntput() not seeing the increment done by __legitimize_mnt().
Solved by a pair of barriers.

Another is that failure of __legitimize_mnt() on the second
read_seqretry() leaves us with reference that'll need to be
dropped by caller; however, if that races with final mntput()
we can end up with caller dropping rcu_read_lock() and doing
mntput() to release that reference - with the first mntput()
having freed the damn thing just as rcu_read_lock() had been
dropped.  Solution: in "do mntput() yourself" failure case
grab mount_lock, check if MNT_DOOMED has been set by racing
final mntput() that has missed our increment and if it has -
undo the increment and treat that as "failure, caller doesn't
need to drop anything" case.

It's not easy to hit - the final mntput() has to come right
after the first read_seqretry() in __legitimize_mnt() *and*
manage to miss the increment done by __legitimize_mnt() before
the second read_seqretry() in there.  The things that are almost
impossible to hit on bare hardware are not impossible on SMP
KVM, though...

Reported-by: Oleg Nesterov <oleg@redhat.com>
Fixes: 48a066e72d97 ("RCU'd vsfmounts")
Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-15 18:12:48 +02:00
Al Viro
d9d46a226d fix mntput/mntput race
commit 9ea0a46ca2c318fcc449c1e6b62a7230a17888f1 upstream.

mntput_no_expire() does the calculation of total refcount under mount_lock;
unfortunately, the decrement (as well as all increments) are done outside
of it, leading to false positives in the "are we dropping the last reference"
test.  Consider the following situation:
	* mnt is a lazy-umounted mount, kept alive by two opened files.  One
of those files gets closed.  Total refcount of mnt is 2.  On CPU 42
mntput(mnt) (called from __fput()) drops one reference, decrementing component
	* After it has looked at component #0, the process on CPU 0 does
mntget(), incrementing component #0, gets preempted and gets to run again -
on CPU 69.  There it does mntput(), which drops the reference (component #69)
and proceeds to spin on mount_lock.
	* On CPU 42 our first mntput() finishes counting.  It observes the
decrement of component #69, but not the increment of component #0.  As the
result, the total it gets is not 1 as it should've been - it's 0.  At which
point we decide that vfsmount needs to be killed and proceed to free it and
shut the filesystem down.  However, there's still another opened file
on that filesystem, with reference to (now freed) vfsmount, etc. and we are
screwed.

It's not a wide race, but it can be reproduced with artificial slowdown of
the mnt_get_count() loop, and it should be easier to hit on SMP KVM setups.

Fix consists of moving the refcount decrement under mount_lock; the tricky
part is that we want (and can) keep the fast case (i.e. mount that still
has non-NULL ->mnt_ns) entirely out of mount_lock.  All places that zero
mnt->mnt_ns are dropping some reference to mnt and they call synchronize_rcu()
before that mntput().  IOW, if mntput() observes (under rcu_read_lock())
a non-NULL ->mnt_ns, it is guaranteed that there is another reference yet to
be dropped.

Reported-by: Jann Horn <jannh@google.com>
Tested-by: Jann Horn <jannh@google.com>
Fixes: 48a066e72d97 ("RCU'd vsfmounts")
Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-15 18:12:48 +02:00
Al Viro
d5426a3841 make sure that __dentry_kill() always invalidates d_seq, unhashed or not
commit 4c0d7cd5c8416b1ef41534d19163cb07ffaa03ab upstream.

RCU pathwalk relies upon the assumption that anything that changes
->d_inode of a dentry will invalidate its ->d_seq.  That's almost
true - the one exception is that the final dput() of already unhashed
dentry does *not* touch ->d_seq at all.  Unhashing does, though,
so for anything we'd found by RCU dcache lookup we are fine.
Unfortunately, we can *start* with an unhashed dentry or jump into
it.

We could try and be careful in the (few) places where that could
happen.  Or we could just make the final dput() invalidate the damn
thing, unhashed or not.  The latter is much simpler and easier to
backport, so let's do it that way.

Reported-by: "Dae R. Jeong" <threeearcat@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-15 18:12:48 +02:00
Al Viro
abfc0ec698 root dentries need RCU-delayed freeing
commit 90bad5e05bcdb0308cfa3d3a60f5c0b9c8e2efb3 upstream.

Since mountpoint crossing can happen without leaving lazy mode,
root dentries do need the same protection against having their
memory freed without RCU delay as everything else in the tree.

It's partially hidden by RCU delay between detaching from the
mount tree and dropping the vfsmount reference, but the starting
point of pathwalk can be on an already detached mount, in which
case umount-caused RCU delay has already passed by the time the
lazy pathwalk grabs rcu_read_lock().  If the starting point
happens to be at the root of that vfsmount *and* that vfsmount
covers the entire filesystem, we get trouble.

Fixes: 48a066e72d97 ("RCU'd vsfmounts")
Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-15 18:12:48 +02:00
Shankara Pailoor
7d29fb5343 jfs: Fix inconsistency between memory allocation and ea_buf->max_size
commit 92d34134193e5b129dc24f8d79cb9196626e8d7a upstream.

The code is assuming the buffer is max_size length, but we weren't
allocating enough space for it.

Signed-off-by: Shankara Pailoor <shankarapailoor@gmail.com>
Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-09 12:16:39 +02:00
Eric Sandeen
59f35b983e xfs: don't call xfs_da_shrink_inode with NULL bp
commit bb3d48dcf86a97dc25fe9fc2c11938e19cb4399a upstream.

xfs_attr3_leaf_create may have errored out before instantiating a buffer,
for example if the blkno is out of range.  In that case there is no work
to do to remove it, and in fact xfs_da_shrink_inode will lead to an oops
if we try.

This also seems to fix a flaw where the original error from
xfs_attr3_leaf_create gets overwritten in the cleanup case, and it
removes a pointless assignment to bp which isn't used after this.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=199969
Reported-by: Xu, Wen <wen.xu@gatech.edu>
Tested-by: Xu, Wen <wen.xu@gatech.edu>
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-09 12:16:39 +02:00
Dave Chinner
6f021e4ef3 xfs: validate cached inodes are free when allocated
commit afca6c5b2595fc44383919fba740c194b0b76aff upstream.

A recent fuzzed filesystem image cached random dcache corruption
when the reproducer was run. This often showed up as panics in
lookup_slow() on a null inode->i_ops pointer when doing pathwalks.

BUG: unable to handle kernel NULL pointer dereference at 0000000000000000
....
Call Trace:
 lookup_slow+0x44/0x60
 walk_component+0x3dd/0x9f0
 link_path_walk+0x4a7/0x830
 path_lookupat+0xc1/0x470
 filename_lookup+0x129/0x270
 user_path_at_empty+0x36/0x40
 path_listxattr+0x98/0x110
 SyS_listxattr+0x13/0x20
 do_syscall_64+0xf5/0x280
 entry_SYSCALL_64_after_hwframe+0x42/0xb7

but had many different failure modes including deadlocks trying to
lock the inode that was just allocated or KASAN reports of
use-after-free violations.

The cause of the problem was a corrupt INOBT on a v4 fs where the
root inode was marked as free in the inobt record. Hence when we
allocated an inode, it chose the root inode to allocate, found it in
the cache and re-initialised it.

We recently fixed a similar inode allocation issue caused by inobt
record corruption problem in xfs_iget_cache_miss() in commit
ee457001ed6c ("xfs: catch inode allocation state mismatch
corruption"). This change adds similar checks to the cache-hit path
to catch it, and turns the reproducer into a corruption shutdown
situation.

Reported-by: Wen Xu <wen.xu@gatech.edu>
Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
[darrick: fix typos in comment]
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-09 12:16:39 +02:00
Dave Chinner
27c41b1701 xfs: catch inode allocation state mismatch corruption
commit ee457001ed6c6f31ddad69c24c1da8f377d8472d upstream.

We recently came across a V4 filesystem causing memory corruption
due to a newly allocated inode being setup twice and being added to
the superblock inode list twice. From code inspection, the only way
this could happen is if a newly allocated inode was not marked as
free on disk (i.e. di_mode wasn't zero).

Running the metadump on an upstream debug kernel fails during inode
allocation like so:

XFS: Assertion failed: ip->i_d.di_nblocks == 0, file: fs/xfs/xfs_inod=
e.c, line: 838
 ------------[ cut here ]------------
kernel BUG at fs/xfs/xfs_message.c:114!
invalid opcode: 0000 [#1] PREEMPT SMP
CPU: 11 PID: 3496 Comm: mkdir Not tainted 4.16.0-rc5-dgc #442
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/0=
1/2014
RIP: 0010:assfail+0x28/0x30
RSP: 0018:ffffc9000236fc80 EFLAGS: 00010202
RAX: 00000000ffffffea RBX: 0000000000004000 RCX: 0000000000000000
RDX: 00000000ffffffc0 RSI: 000000000000000a RDI: ffffffff8227211b
RBP: ffffc9000236fce8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000bec R11: f000000000000000 R12: ffffc9000236fd30
R13: ffff8805c76bab80 R14: ffff8805c77ac800 R15: ffff88083fb12e10
FS:  00007fac8cbff040(0000) GS:ffff88083fd00000(0000) knlGS:0000000000000=
000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fffa6783ff8 CR3: 00000005c6e2b003 CR4: 00000000000606e0
Call Trace:
 xfs_ialloc+0x383/0x570
 xfs_dir_ialloc+0x6a/0x2a0
 xfs_create+0x412/0x670
 xfs_generic_create+0x1f7/0x2c0
 ? capable_wrt_inode_uidgid+0x3f/0x50
 vfs_mkdir+0xfb/0x1b0
 SyS_mkdir+0xcf/0xf0
 do_syscall_64+0x73/0x1a0
 entry_SYSCALL_64_after_hwframe+0x42/0xb7

Extracting the inode number we crashed on from an event trace and
looking at it with xfs_db:

xfs_db> inode 184452204
xfs_db> p
core.magic = 0x494e
core.mode = 0100644
core.version = 2
core.format = 2 (extents)
core.nlinkv2 = 1
core.onlink = 0
.....

Confirms that it is not a free inode on disk. xfs_repair
also trips over this inode:

.....
zero length extent (off = 0, fsbno = 0) in ino 184452204
correcting nextents for inode 184452204
bad attribute fork in inode 184452204, would clear attr fork
bad nblocks 1 for inode 184452204, would reset to 0
bad anextents 1 for inode 184452204, would reset to 0
imap claims in-use inode 184452204 is free, would correct imap
would have cleared inode 184452204
.....
disconnected inode 184452204, would move to lost+found

And so we have a situation where the directory structure and the
inobt thinks the inode is free, but the inode on disk thinks it is
still in use. Where this corruption came from is not possible to
diagnose, but we can detect it and prevent the kernel from oopsing
on lookup. The reproducer now results in:

$ sudo mkdir /mnt/scratch/{0,1,2,3,4,5}{0,1,2,3,4,5}
mkdir: cannot create directory =E2=80=98/mnt/scratch/00=E2=80=99: File ex=
ists
mkdir: cannot create directory =E2=80=98/mnt/scratch/01=E2=80=99: File ex=
ists
mkdir: cannot create directory =E2=80=98/mnt/scratch/03=E2=80=99: Structu=
re needs cleaning
mkdir: cannot create directory =E2=80=98/mnt/scratch/04=E2=80=99: Input/o=
utput error
mkdir: cannot create directory =E2=80=98/mnt/scratch/05=E2=80=99: Input/o=
utput error
....

And this corruption shutdown:

[   54.843517] XFS (loop0): Corruption detected! Free inode 0xafe846c not=
 marked free on disk
[   54.845885] XFS (loop0): Internal error xfs_trans_cancel at line 1023 =
of file fs/xfs/xfs_trans.c.  Caller xfs_create+0x425/0x670
[   54.848994] CPU: 10 PID: 3541 Comm: mkdir Not tainted 4.16.0-rc5-dgc #=
443
[   54.850753] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIO=
S 1.10.2-1 04/01/2014
[   54.852859] Call Trace:
[   54.853531]  dump_stack+0x85/0xc5
[   54.854385]  xfs_trans_cancel+0x197/0x1c0
[   54.855421]  xfs_create+0x425/0x670
[   54.856314]  xfs_generic_create+0x1f7/0x2c0
[   54.857390]  ? capable_wrt_inode_uidgid+0x3f/0x50
[   54.858586]  vfs_mkdir+0xfb/0x1b0
[   54.859458]  SyS_mkdir+0xcf/0xf0
[   54.860254]  do_syscall_64+0x73/0x1a0
[   54.861193]  entry_SYSCALL_64_after_hwframe+0x42/0xb7
[   54.862492] RIP: 0033:0x7fb73bddf547
[   54.863358] RSP: 002b:00007ffdaa553338 EFLAGS: 00000246 ORIG_RAX: 0000=
000000000053
[   54.865133] RAX: ffffffffffffffda RBX: 00007ffdaa55449a RCX: 00007fb73=
bddf547
[   54.866766] RDX: 0000000000000001 RSI: 00000000000001ff RDI: 00007ffda=
a55449a
[   54.868432] RBP: 00007ffdaa55449a R08: 00000000000001ff R09: 00005623a=
8670dd0
[   54.870110] R10: 00007fb73be72d5b R11: 0000000000000246 R12: 000000000=
00001ff
[   54.871752] R13: 00007ffdaa5534b0 R14: 0000000000000000 R15: 00007ffda=
a553500
[   54.873429] XFS (loop0): xfs_do_force_shutdown(0x8) called from line 1=
024 of file fs/xfs/xfs_trans.c.  Return address = ffffffff814cd050
[   54.882790] XFS (loop0): Corruption of in-memory data detected.  Shutt=
ing down filesystem
[   54.884597] XFS (loop0): Please umount the filesystem and rectify the =
problem(s)

Note that this crash is only possible on v4 filesystemsi or v5
filesystems mounted with the ikeep mount option. For all other V5
filesystems, this problem cannot occur because we don't read inodes
we are allocating from disk - we simply overwrite them with the new
inode information.

Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Tested-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-09 12:16:39 +02:00
Filipe Manana
0ea7fcfc7f Btrfs: fix file data corruption after cloning a range and fsync
commit bd3599a0e142cd73edd3b6801068ac3f48ac771a upstream.

When we clone a range into a file we can end up dropping existing
extent maps (or trimming them) and replacing them with new ones if the
range to be cloned overlaps with a range in the destination inode.
When that happens we add the new extent maps to the list of modified
extents in the inode's extent map tree, so that a "fast" fsync (the flag
BTRFS_INODE_NEEDS_FULL_SYNC not set in the inode) will see the extent maps
and log corresponding extent items. However, at the end of range cloning
operation we do truncate all the pages in the affected range (in order to
ensure future reads will not get stale data). Sometimes this truncation
will release the corresponding extent maps besides the pages from the page
cache. If this happens, then a "fast" fsync operation will miss logging
some extent items, because it relies exclusively on the extent maps being
present in the inode's extent tree, leading to data loss/corruption if
the fsync ends up using the same transaction used by the clone operation
(that transaction was not committed in the meanwhile). An extent map is
released through the callback btrfs_invalidatepage(), which gets called by
truncate_inode_pages_range(), and it calls __btrfs_releasepage(). The
later ends up calling try_release_extent_mapping() which will release the
extent map if some conditions are met, like the file size being greater
than 16Mb, gfp flags allow blocking and the range not being locked (which
is the case during the clone operation) nor being the extent map flagged
as pinned (also the case for cloning).

The following example, turned into a test for fstests, reproduces the
issue:

  $ mkfs.btrfs -f /dev/sdb
  $ mount /dev/sdb /mnt

  $ xfs_io -f -c "pwrite -S 0x18 9000K 6908K" /mnt/foo
  $ xfs_io -f -c "pwrite -S 0x20 2572K 156K" /mnt/bar

  $ xfs_io -c "fsync" /mnt/bar
  # reflink destination offset corresponds to the size of file bar,
  # 2728Kb minus 4Kb.
  $ xfs_io -c ""reflink ${SCRATCH_MNT}/foo 0 2724K 15908K" /mnt/bar
  $ xfs_io -c "fsync" /mnt/bar

  $ md5sum /mnt/bar
  95a95813a8c2abc9aa75a6c2914a077e  /mnt/bar

  <power fail>

  $ mount /dev/sdb /mnt
  $ md5sum /mnt/bar
  207fd8d0b161be8a84b945f0df8d5f8d  /mnt/bar
  # digest should be 95a95813a8c2abc9aa75a6c2914a077e like before the
  # power failure

In the above example, the destination offset of the clone operation
corresponds to the size of the "bar" file minus 4Kb. So during the clone
operation, the extent map covering the range from 2572Kb to 2728Kb gets
trimmed so that it ends at offset 2724Kb, and a new extent map covering
the range from 2724Kb to 11724Kb is created. So at the end of the clone
operation when we ask to truncate the pages in the range from 2724Kb to
2724Kb + 15908Kb, the page invalidation callback ends up removing the new
extent map (through try_release_extent_mapping()) when the page at offset
2724Kb is passed to that callback.

Fix this by setting the bit BTRFS_INODE_NEEDS_FULL_SYNC whenever an extent
map is removed at try_release_extent_mapping(), forcing the next fsync to
search for modified extents in the fs/subvolume tree instead of relying on
the presence of extent maps in memory. This way we can continue doing a
"fast" fsync if the destination range of a clone operation does not
overlap with an existing range or if any of the criteria necessary to
remove an extent map at try_release_extent_mapping() is not met (file
size not bigger then 16Mb or gfp flags do not allow blocking).

CC: stable@vger.kernel.org # 3.16+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-09 12:16:39 +02:00
Theodore Ts'o
dd69abaccb ext4: fix false negatives *and* false positives in ext4_check_descriptors()
commit 44de022c4382541cebdd6de4465d1f4f465ff1dd upstream.

Ext4_check_descriptors() was getting called before s_gdb_count was
initialized.  So for file systems w/o the meta_bg feature, allocation
bitmaps could overlap the block group descriptors and ext4 wouldn't
notice.

For file systems with the meta_bg feature enabled, there was a
fencepost error which would cause the ext4_check_descriptors() to
incorrectly believe that the block allocation bitmap overlaps with the
block group descriptor blocks, and it would reject the mount.

Fix both of these problems.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
Signed-off-by: Benjamin Gilbert <bgilbert@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-09 12:16:38 +02:00
Mike Rapoport
0eba9f5d3d userfaultfd: remove uffd flags from vma->vm_flags if UFFD_EVENT_FORK fails
commit 31e810aa1033a7db50a2746cd34a2432237f6420 upstream.

The fix in commit 0cbb4b4f4c44 ("userfaultfd: clear the
vma->vm_userfaultfd_ctx if UFFD_EVENT_FORK fails") cleared the
vma->vm_userfaultfd_ctx but kept userfaultfd flags in vma->vm_flags
that were copied from the parent process VMA.

As the result, there is an inconsistency between the values of
vma->vm_userfaultfd_ctx.ctx and vma->vm_flags which triggers BUG_ON
in userfaultfd_release().

Clearing the uffd flags from vma->vm_flags in case of UFFD_EVENT_FORK
failure resolves the issue.

Link: http://lkml.kernel.org/r/1532931975-25473-1-git-send-email-rppt@linux.vnet.ibm.com
Fixes: 0cbb4b4f4c44 ("userfaultfd: clear the vma->vm_userfaultfd_ctx if UFFD_EVENT_FORK fails")
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Reported-by: syzbot+121be635a7a35ddb7dcb@syzkaller.appspotmail.com
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-06 16:20:49 +02:00
Linus Torvalds
e7de67165e squashfs: more metadata hardenings
commit 71755ee5350b63fb1f283de8561cdb61b47f4d1d upstream.

The squashfs fragment reading code doesn't actually verify that the
fragment is inside the fragment table.  The end result _is_ verified to
be inside the image when actually reading the fragment data, but before
that is done, we may end up taking a page fault because the fragment
table itself might not even exist.

Another report from Anatoly and his endless squashfs image fuzzing.

Reported-by: Анатолий Тросиненко <anatoly.trosinenko@gmail.com>
Acked-by:: Phillip Lougher <phillip.lougher@gmail.com>,
Cc: Willy Tarreau <w@1wt.eu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-06 16:20:48 +02:00
Linus Torvalds
953f918d54 squashfs: more metadata hardening
commit d512584780d3e6a7cacb2f482834849453d444a1 upstream.

Anatoly reports another squashfs fuzzing issue, where the decompression
parameters themselves are in a compressed block.

This causes squashfs_read_data() to be called in order to read the
decompression options before the decompression stream having been set
up, making squashfs go sideways.

Reported-by: Anatoly Trosinenko <anatoly.trosinenko@gmail.com>
Acked-by: Phillip Lougher <phillip.lougher@gmail.com>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-06 16:20:48 +02:00
Chengguang Xu
6aaaca7b81 ovl: Sync upper dirty data when syncing overlayfs
commit e8d4bfe3a71537284a90561f77c85dea6c154369 upstream.

When executing filesystem sync or umount on overlayfs,
dirty data does not get synced as expected on upper filesystem.
This patch fixes sync filesystem method to keep data consistency
for overlayfs.

Signed-off-by: Chengguang Xu <cgxu@mykernel.net>
Fixes: e593b2bf513d ("ovl: properly implement sync_filesystem()")
Cc: <stable@vger.kernel.org> #4.11
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-03 07:50:43 +02:00
Theodore Ts'o
f547aa20b4 ext4: fix check to prevent initializing reserved inodes
commit 5012284700775a4e6e3fbe7eac4c543c4874b559 upstream.

Commit 8844618d8aa7: "ext4: only look at the bg_flags field if it is
valid" will complain if block group zero does not have the
EXT4_BG_INODE_ZEROED flag set.  Unfortunately, this is not correct,
since a freshly created file system has this flag cleared.  It gets
almost immediately after the file system is mounted read-write --- but
the following somewhat unlikely sequence will end up triggering a
false positive report of a corrupted file system:

   mkfs.ext4 /dev/vdc
   mount -o ro /dev/vdc /vdc
   mount -o remount,rw /dev/vdc

Instead, when initializing the inode table for block group zero, test
to make sure that itable_unused count is not too large, since that is
the case that will result in some or all of the reserved inodes
getting cleared.

This fixes the failures reported by Eric Whiteney when running
generic/230 and generic/231 in the the nojournal test case.

Fixes: 8844618d8aa7 ("ext4: only look at the bg_flags field if it is valid")
Reported-by: Eric Whitney <enwlinux@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-03 07:50:43 +02:00
Theodore Ts'o
dc1b4b710f ext4: check for allocation block validity with block group locked
commit 8d5a803c6a6ce4ec258e31f76059ea5153ba46ef upstream.

With commit 044e6e3d74a3: "ext4: don't update checksum of new
initialized bitmaps" the buffer valid bit will get set without
actually setting up the checksum for the allocation bitmap, since the
checksum will get calculated once we actually allocate an inode or
block.

If we are doing this, then we need to (re-)check the verified bit
after we take the block group lock.  Otherwise, we could race with
another process reading and verifying the bitmap, which would then
complain about the checksum being invalid.

https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1780137

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-03 07:50:43 +02:00
Theodore Ts'o
cdcbe750ac ext4: fix inline data updates with checksums enabled
commit 362eca70b53389bddf3143fe20f53dcce2cfdf61 upstream.

The inline data code was updating the raw inode directly; this is
problematic since if metadata checksums are enabled,
ext4_mark_inode_dirty() must be called to update the inode's checksum.
In addition, the jbd2 layer requires that get_write_access() be called
before the metadata buffer is modified.  Fix both of these problems.

https://bugzilla.kernel.org/show_bug.cgi?id=200443

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-03 07:50:43 +02:00