commit 93533c7855 upstream.
xfs_iext_lookup_extent looks up a single extent at the passed in offset,
and returns the extent covering the area, or the one behind it in case
of a hole, as well as the index of the returned extent in arguments,
as well as a simple bool as return value that is set to false if no
extent could be found because the offset is behind EOF. It is a simpler
replacement for xfs_bmap_search_extent that leaves looking up the rarely
needed previous extent to the caller and has a nicer calling convention.
xfs_iext_get_extent is a helper for iterating over the extent list,
it takes an extent index as input, and returns the extent at that index
in it's expanded form in an argument if it exists. The actual return
value is a bool whether the index is valid or not.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 98efe8af1c upstream.
Filesystem shutdown testing on an older distro kernel has uncovered an
imbalanced locking pattern for the inode flush lock in
xfs_reclaim_inode(). Specifically, there is a double unlock sequence
between the call to xfs_iflush_abort() and xfs_reclaim_inode() at the
"reclaim:" label.
This actually does not cause obvious problems on current kernels due to
the current flush lock implementation. Older kernels use a counting
based flush lock mechanism, however, which effectively breaks the lock
indefinitely when an already unlocked flush lock is repeatedly unlocked.
Though this only currently occurs on filesystem shutdown, it has
reproduced the effect of elevating an fs shutdown to a system-wide crash
or hang.
As it turns out, the flush lock is not actually required for the reclaim
logic in xfs_reclaim_inode() because by that time we have already cycled
the flush lock once while holding ILOCK_EXCL. Therefore, remove the
additional flush lock/unlock cycle around the 'reclaim:' label and
update branches into this label to release the flush lock where
appropriate. Add an assert to xfs_ifunlock() to help prevent future
occurences of the same problem.
Reported-by: Zorro Lang <zlang@redhat.com>
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 5d829300be upstream.
The open-coded pattern:
ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t)
is all over the xfs code; provide a new helper
xfs_iext_count(ifp) to count the number of inline extents
in an inode fork.
[dchinner: pick up several missed conversions]
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 04197b341f upstream.
We've had reports of generic/095 causing XFS to BUG() in
__xfs_get_blocks() due to the existence of delalloc blocks on a
direct I/O read. generic/095 issues a mix of various types of I/O,
including direct and memory mapped I/O to a single file. This is
clearly not supported behavior and is known to lead to such
problems. E.g., the lack of exclusion between the direct I/O and
write fault paths means that a write fault can allocate delalloc
blocks in a region of a file that was previously a hole after the
direct read has attempted to flush/inval the file range, but before
it actually reads the block mapping. In turn, the direct read
discovers a delalloc extent and cannot proceed.
While the appropriate solution here is to not mix direct and memory
mapped I/O to the same regions of the same file, the current
BUG_ON() behavior is probably overkill as it can crash the entire
system. Instead, localize the failure to the I/O in question by
returning an error for a direct I/O that cannot be handled safely
due to delalloc blocks. Be careful to allow the case of a direct
write to post-eof delalloc blocks. This can occur due to speculative
preallocation and is safe as post-eof blocks are not accompanied by
dirty pages in pagecache (conversely, preallocation within eof must
have been zeroed, and thus dirtied, before the inode size could have
been increased beyond said blocks).
Finally, provide an additional warning if a direct I/O write occurs
while the file is memory mapped. This may not catch all problematic
scenarios, but provides a hint that some known-to-be-problematic I/O
methods are in use.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 399372349a upstream.
The cowblocks background scanner currently clears the cowblocks tag
for inodes without any real allocations in the cow fork. This
excludes inodes with only delalloc blocks in the cow fork. While we
might never expect to clear delalloc blocks from the cow fork in the
background scanner, it is not necessarily correct to clear the
cowblocks tag from such inodes.
For example, if the background scanner happens to process an inode
between a buffered write and writeback, the scanner catches the
inode in a state after delalloc blocks have been allocated to the
cow fork but before the delalloc blocks have been converted to real
blocks by writeback. The background scanner then incorrectly clears
the cowblocks tag, even if part of the aforementioned delalloc
reservation will not be remapped to the data fork (i.e., extra
blocks due to the cowextsize hint). This means that any such
additional blocks in the cow fork might never be reclaimed by the
background scanner and could persist until the inode itself is
reclaimed.
To address this problem, only skip and clear inodes without any cow
fork allocations whatsoever from the background scanner. While we
generally do not want to cancel delalloc reservations from the
background scanner, the pagecache dirty check following the
cowblocks check should prevent that situation. If we do end up with
delalloc cow fork blocks without a dirty address space mapping, this
is probably an indication that something has gone wrong and the
blocks should be reclaimed, as they may never be converted to a real
allocation.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit e6fc6fcf44 upstream.
Source xfsprogs commit: ee3754254e8c186c99b6cdd4d59f741759d04acb
Kernel commit 5ef828c4 ("xfs: avoid false quotacheck after unclean
shutdown") made xfs_sb_from_disk() also call xfs_sb_quota_from_disk
by default.
However, when this was merged to libxfs, existing separate
calls to libxfs_sb_quota_from_disk remained, and calling it
twice in a row on a V4 superblock leads to issues, because:
if (sbp->sb_qflags & XFS_PQUOTA_ACCT) {
...
sbp->sb_pquotino = sbp->sb_gquotino;
sbp->sb_gquotino = NULLFSINO;
and after the second call, we have set both pquotino and gquotino
to NULLFSINO.
Fix this by making it safe to call twice, and also remove the extra
calls to libxfs_sb_quota_from_disk.
This is only spotted when running xfstests with "-m crc=0" because
the sb_from_disk change came about after V5 became default, and
the above behavior only exists on a V4 superblock.
Reported-by: Eryu Guan <eguan@redhat.com>
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 230436b3ef upstream.
gcc is unsure about the use of last_ofs_in_node, which might happen
without a prior initialization:
fs/f2fs//git/arm-soc/fs/f2fs/data.c: In function ‘f2fs_map_blocks’:
fs/f2fs/data.c:799:54: warning: ‘last_ofs_in_node’ may be used uninitialized in this function [-Wmaybe-uninitialized]
if (prealloc && dn.ofs_in_node != last_ofs_in_node + 1) {
As pointed out by Chao Yu, the code is actually correct as 'prealloc'
is only set if the last_ofs_in_node has been set, the two always
get updated together.
This initializes last_ofs_in_node to dn.ofs_in_node for each
new dnode at the start of the 'next_block' loop, which at that
point is a correct initialization as well. I assume that compilers
that correctly track the contents of the variables and do not
warn about the condition also figure out that they can eliminate
the extra assignment here.
Fixes: 46008c6d42 ("f2fs: support in batch multi blocks preallocation")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 35782b233f upstream.
This patch removes percpu_count usage due to performance regression in iozone.
Fixes: 523be8a6b3 ("f2fs: use percpu_counter for page counters")
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 42d97eb0ad upstream.
Attempting to link a device node, named pipe, or socket file into an
encrypted directory through rename(2) or link(2) always failed with
EPERM. This happened because fscrypt_has_permitted_context() saw that
the file was unencrypted and forbid creating the link. This behavior
was unexpected because such files are never encrypted; only regular
files, directories, and symlinks can be encrypted.
To fix this, make fscrypt_has_permitted_context() always return true on
special files.
This will be covered by a test in my encryption xfstests patchset.
Fixes: 9bd8212f98 ("ext4 crypto: add encryption policy and password salt support")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 54e4a0dfa2 upstream.
We must not call nfs_pageio_init_read() on a new nfs_pageio_descriptor
while holding a reference to a layout segment, as that can deadlock
pnfs_update_layout().
Fixes: d67ae825a5 ("pnfs/flexfiles: Add the FlexFile Layout Driver")
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit ae5a459d5f upstream.
We must ensure that we don't schedule a layoutreturn if the layout stateid
has been marked as invalid.
Fixes: 2a59a04116 ("pNFS: Fix pnfs_set_layout_stateid() to clear...")
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 7b650994ab upstream.
If we no longer hold any layout segments, we're normally expected to
consider the layout stateid to be invalid. However we cannot assume this
if we're about to, or in the process of sending a layoutreturn.
Fixes: 334a8f3711 ("pNFS: Don't forget the layout stateid if...")
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 6604b203fb upstream.
If there is an I/O error, we should not call LAYOUTGET until the
LAYOUTRETURN that reports the error is complete.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit c0cf3ef5e0 upstream.
What matters when deciding if we should make a page uptodate is
not how much we _wanted_ to copy, but how much we actually have
copied. As it is, on architectures that do not zero tail on
short copy we can leave uninitialized data in page marked uptodate.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 3f9ca75516 upstream.
New inode operations were forgotten to be added to bad_inode. Most of the
time the op is checked for NULL before being called but marking the inode
bad and the check can race (very unlikely).
However in case of ->get_link() only DCACHE_SYMLINK_TYPE is checked before
calling the op, so there's no race and will definitely oops when trying to
follow links on such a beast.
Also remove comments about extinct ops.
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 5716863e0f upstream.
fsnotify_unmount_inodes() plays complex tricks to pin next inode in the
sb->s_inodes list when iterating over all inodes. Furthermore the code has a
bug that if the current inode is the last on i_sb_list that does not have e.g.
I_FREEING set, then we leave next_i pointing to inode which may get removed
from the i_sb_list once we drop s_inode_list_lock thus resulting in
use-after-free issues (usually manifesting as infinite looping in
fsnotify_unmount_inodes()).
Fix the problem by keeping current inode pinned somewhat longer. Then we can
make the code much simpler and standard.
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 6b10b23ca9 upstream.
xlog_recover_clear_agi_bucket didn't set the
type to XFS_BLFT_AGI_BUF, so we got a warning during log
replay (or an ASSERT on a debug build).
XFS (md0): Unknown buffer type 0!
XFS (md0): _xfs_buf_ioapply: no ops on block 0xaea8802/0x1
Fix this, as was done in f19b872b for 2 other locations
with the same problem.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 4dfce57db6 upstream.
There have been several reports over the years of NULL pointer
dereferences in xfs_trans_log_inode during xfs_fsr processes,
when the process is doing an fput and tearing down extents
on the temporary inode, something like:
BUG: unable to handle kernel NULL pointer dereference at 0000000000000018
PID: 29439 TASK: ffff880550584fa0 CPU: 6 COMMAND: "xfs_fsr"
[exception RIP: xfs_trans_log_inode+0x10]
#9 [ffff8800a57bbbe0] xfs_bunmapi at ffffffffa037398e [xfs]
#10 [ffff8800a57bbce8] xfs_itruncate_extents at ffffffffa0391b29 [xfs]
#11 [ffff8800a57bbd88] xfs_inactive_truncate at ffffffffa0391d0c [xfs]
#12 [ffff8800a57bbdb8] xfs_inactive at ffffffffa0392508 [xfs]
#13 [ffff8800a57bbdd8] xfs_fs_evict_inode at ffffffffa035907e [xfs]
#14 [ffff8800a57bbe00] evict at ffffffff811e1b67
#15 [ffff8800a57bbe28] iput at ffffffff811e23a5
#16 [ffff8800a57bbe58] dentry_kill at ffffffff811dcfc8
#17 [ffff8800a57bbe88] dput at ffffffff811dd06c
#18 [ffff8800a57bbea8] __fput at ffffffff811c823b
#19 [ffff8800a57bbef0] ____fput at ffffffff811c846e
#20 [ffff8800a57bbf00] task_work_run at ffffffff81093b27
#21 [ffff8800a57bbf30] do_notify_resume at ffffffff81013b0c
#22 [ffff8800a57bbf50] int_signal at ffffffff8161405d
As it turns out, this is because the i_itemp pointer, along
with the d_ops pointer, has been overwritten with zeros
when we tear down the extents during truncate. When the in-core
inode fork on the temporary inode used by xfs_fsr was originally
set up during the extent swap, we mistakenly looked at di_nextents
to determine whether all extents fit inline, but this misses extents
generated by speculative preallocation; we should be using if_bytes
instead.
This mistake corrupts the in-memory inode, and code in
xfs_iext_remove_inline eventually gets bad inputs, causing
it to memmove and memset incorrect ranges; this became apparent
because the two values in ifp->if_u2.if_inline_ext[1] contained
what should have been in d_ops and i_itemp; they were memmoved due
to incorrect array indexing and then the original locations
were zeroed with memset, again due to an array overrun.
Fix this by properly using i_df.if_bytes to determine the number
of extents, not di_nextents.
Thanks to dchinner for looking at this with me and spotting the
root cause.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit e3d240e9d5 upstream.
If maxBuf is not 0 but less than a size of SMB2 lock structure
we can end up with a memory corruption.
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 96a988ffeb upstream.
With the current code it is possible to lock a mutex twice when
a subsequent reconnects are triggered. On the 1st reconnect we
reconnect sessions and tcons and then persistent file handles.
If the 2nd reconnect happens during the reconnecting of persistent
file handles then the following sequence of calls is observed:
cifs_reopen_file -> SMB2_open -> small_smb2_init -> smb2_reconnect
-> cifs_reopen_persistent_file_handles -> cifs_reopen_file (again!).
So, we are trying to acquire the same cfile->fh_mutex twice which
is wrong. Fix this by moving reconnecting of persistent handles to
the delayed work (smb2_reconnect_server) and submitting this work
every time we reconnect tcon in SMB2 commands handling codepath.
This can also lead to corruption of a temporary file list in
cifs_reopen_persistent_file_handles() because we can recursively
call this function twice.
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 53e0e11efe upstream.
We can not unlock/lock cifs_tcp_ses_lock while walking through ses
and tcon lists because it can corrupt list iterator pointers and
a tcon structure can be released if we don't hold an extra reference.
Fix it by moving a reconnect process to a separate delayed work
and acquiring a reference to every tcon that needs to be reconnected.
Also do not send an echo request on newly established connections.
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 06deeec77a upstream.
smbencrypt() points a scatterlist to the stack, which is breaks if
CONFIG_VMAP_STACK=y.
Fix it by switching to crypto_cipher_encrypt_one(). The new code
should be considerably faster as an added benefit.
This code is nearly identical to some code that Eric Biggers
suggested.
Reported-by: Eric Biggers <ebiggers3@gmail.com>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 8508e44ae9 upstream.
We don't guarantee cp_addr is fixed by cp_version.
This is to sync with f2fs-tools.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit e87f7329bb upstream.
In the last ilen case, i was already increased, resulting in accessing out-
of-boundary entry of do_replace and blkaddr.
Fix to check ilen first to exit the loop.
Fixes: 2aa8fbb9693020 ("f2fs: refactor __exchange_data_block for speed up")
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 05e6ea2685 upstream.
The struct file_operations instance serving the f2fs/status debugfs file
lacks an initialization of its ->owner.
This means that although that file might have been opened, the f2fs module
can still get removed. Any further operation on that opened file, releasing
included, will cause accesses to unmapped memory.
Indeed, Mike Marshall reported the following:
BUG: unable to handle kernel paging request at ffffffffa0307430
IP: [<ffffffff8132a224>] full_proxy_release+0x24/0x90
<...>
Call Trace:
[] __fput+0xdf/0x1d0
[] ____fput+0xe/0x10
[] task_work_run+0x8e/0xc0
[] do_exit+0x2ae/0xae0
[] ? __audit_syscall_entry+0xae/0x100
[] ? syscall_trace_enter+0x1ca/0x310
[] do_group_exit+0x44/0xc0
[] SyS_exit_group+0x14/0x20
[] do_syscall_64+0x61/0x150
[] entry_SYSCALL64_slow_path+0x25/0x25
<...>
---[ end trace f22ae883fa3ea6b8 ]---
Fixing recursive fault but reboot is needed!
Fix this by initializing the f2fs/status file_operations' ->owner with
THIS_MODULE.
This will allow debugfs to grab a reference to the f2fs module upon any
open on that file, thus preventing it from getting removed.
Fixes: 902829aa0b ("f2fs: move proc files to debugfs")
Reported-by: Mike Marshall <hubcap@omnibond.com>
Reported-by: Martin Brandenburg <martin@omnibond.com>
Signed-off-by: Nicolai Stange <nicstange@gmail.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 204706c7ac upstream.
This reverts commit 1beba1b3a9.
The perpcu_counter doesn't provide atomicity in single core and consume more
DRAM. That incurs fs_mark test failure due to ENOMEM.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 73b92a2a5e upstream.
Currently data journalling is incompatible with encryption: enabling both
at the same time has never been supported by design, and would result in
unpredictable behavior. However, users are not precluded from turning on
both features simultaneously. This change programmatically replaces data
journaling for encrypted regular files with ordered data journaling mode.
Background:
Journaling encrypted data has not been supported because it operates on
buffer heads of the page in the page cache. Namely, when the commit
happens, which could be up to five seconds after caching, the commit
thread uses the buffer heads attached to the page to copy the contents of
the page to the journal. With encryption, it would have been required to
keep the bounce buffer with ciphertext for up to the aforementioned five
seconds, since the page cache can only hold plaintext and could not be
used for journaling. Alternatively, it would be required to setup the
journal to initiate a callback at the commit time to perform deferred
encryption - in this case, not only would the data have to be written
twice, but it would also have to be encrypted twice. This level of
complexity was not justified for a mode that in practice is very rarely
used because of the overhead from the data journalling.
Solution:
If data=journaled has been set as a mount option for a filesystem, or if
journaling is enabled on a regular file, do not perform journaling if the
file is also encrypted, instead fall back to the data=ordered mode for the
file.
Rationale:
The intent is to allow seamless and proper filesystem operation when
journaling and encryption have both been enabled, and have these two
conflicting features gracefully resolved by the filesystem.
Fixes: 4461471107
Signed-off-by: Sergey Karamov <skaramov@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 7e6e1ef48f upstream.
Don't load an inode with a negative size; this causes integer overflow
problems in the VFS.
[ Added EXT4_ERROR_INODE() to mark file system as corrupted. -TYT]
Fixes: a48380f769 (ext4: rename i_dir_acl to i_size_high)
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit c48ae41baf upstream.
The commit "ext4: sanity check the block and cluster size at mount
time" should prevent any problems, but in case the superblock is
modified while the file system is mounted, add an extra safety check
to make sure we won't overrun the allocated buffer.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 5aee0f8a3f upstream.
Fix a large number of problems with how we handle mount options in the
superblock. For one, if the string in the superblock is long enough
that it is not null terminated, we could run off the end of the string
and try to interpret superblocks fields as characters. It's unlikely
this will cause a security problem, but it could result in an invalid
parse. Also, parse_options is destructive to the string, so in some
cases if there is a comma-separated string, it would be modified in
the superblock. (Fortunately it only happens on file systems with a
1k block size.)
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit cd6bb35bf7 upstream.
Centralize the checks for inodes_per_block and be more strict to make
sure the inodes_per_block_group can't end up being zero.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 30a9d7afe7 upstream.
The number of 'counters' elements needed in 'struct sg' is
super_block->s_blocksize_bits + 2. Presently we have 16 'counters'
elements in the array. This is insufficient for block sizes >= 32k. In
such cases the memcpy operation performed in ext4_mb_seq_groups_show()
would cause stack memory corruption.
Fixes: c9de560ded
Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 69e43e8cc9 upstream.
'border' variable is set to a value of 2 times the block size of the
underlying filesystem. With 64k block size, the resulting value won't
fit into a 16-bit variable. Hence this commit changes the data type of
'border' to 'unsigned int'.
Fixes: c9de560ded
Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 1566a48aaa upstream.
If there is an error reported in mballoc via ext4_grp_locked_error(),
the code is holding a spinlock, so ext4_commit_super() must not try to
lock the buffer head, or else it will trigger a BUG:
BUG: sleeping function called from invalid context at ./include/linux/buffer_head.h:358
in_atomic(): 1, irqs_disabled(): 0, pid: 993, name: mount
CPU: 0 PID: 993 Comm: mount Not tainted 4.9.0-rc1-clouder1 #62
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.8.1-0-g4adadbd-20150316_085822-nilsson.home.kraxel.org 04/01/2014
ffff880006423548 ffffffff81318c89 ffffffff819ecdd0 0000000000000166
ffff880006423558 ffffffff810810b0 ffff880006423580 ffffffff81081153
ffff880006e5a1a0 ffff88000690e400 0000000000000000 ffff8800064235c0
Call Trace:
[<ffffffff81318c89>] dump_stack+0x67/0x9e
[<ffffffff810810b0>] ___might_sleep+0xf0/0x140
[<ffffffff81081153>] __might_sleep+0x53/0xb0
[<ffffffff8126c1dc>] ext4_commit_super+0x19c/0x290
[<ffffffff8126e61a>] __ext4_grp_locked_error+0x14a/0x230
[<ffffffff81081153>] ? __might_sleep+0x53/0xb0
[<ffffffff812822be>] ext4_mb_generate_buddy+0x1de/0x320
Since ext4_grp_locked_error() calls ext4_commit_super with sync == 0
(and it is the only caller which does so), avoid locking and unlocking
the buffer in this case.
This can result in races with ext4_commit_super() if there are other
problems (which is what commit 4743f83990 was trying to address),
but a Warning is better than BUG.
Fixes: 4743f83990
Reported-by: Nikolay Borisov <kernel@kyup.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 64b875f7ac upstream.
When the flag PT_PTRACE_CAP was added the PTRACE_TRACEME path was
overlooked. This can result in incorrect behavior when an application
like strace traces an exec of a setuid executable.
Further PT_PTRACE_CAP does not have enough information for making good
security decisions as it does not report which user namespace the
capability is in. This has already allowed one mistake through
insufficient granulariy.
I found this issue when I was testing another corner case of exec and
discovered that I could not get strace to set PT_PTRACE_CAP even when
running strace as root with a full set of caps.
This change fixes the above issue with strace allowing stracing as
root a setuid executable without disabling setuid. More fundamentaly
this change allows what is allowable at all times, by using the correct
information in it's decision.
Fixes: 4214e42f96d4 ("v2.4.9.11 -> v2.4.9.12")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit bcc7f5b4be upstream.
bdev->bd_contains is not stable before calling __blkdev_get().
When __blkdev_get() is called on a parition with ->bd_openers == 0
it sets
bdev->bd_contains = bdev;
which is not correct for a partition.
After a call to __blkdev_get() succeeds, ->bd_openers will be > 0
and then ->bd_contains is stable.
When FMODE_EXCL is used, blkdev_get() calls
bd_start_claiming() -> bd_prepare_to_claim() -> bd_may_claim()
This call happens before __blkdev_get() is called, so ->bd_contains
is not stable. So bd_may_claim() cannot safely use ->bd_contains.
It currently tries to use it, and this can lead to a BUG_ON().
This happens when a whole device is already open with a bd_holder (in
use by dm in my particular example) and two threads race to open a
partition of that device for the first time, one opening with O_EXCL and
one without.
The thread that doesn't use O_EXCL gets through blkdev_get() to
__blkdev_get(), gains the ->bd_mutex, and sets bdev->bd_contains = bdev;
Immediately thereafter the other thread, using FMODE_EXCL, calls
bd_start_claiming() from blkdev_get(). This should fail because the
whole device has a holder, but because bdev->bd_contains == bdev
bd_may_claim() incorrectly reports success.
This thread continues and blocks on bd_mutex.
The first thread then sets bdev->bd_contains correctly and drops the mutex.
The thread using FMODE_EXCL then continues and when it calls bd_may_claim()
again in:
BUG_ON(!bd_may_claim(bdev, whole, holder));
The BUG_ON fires.
Fix this by removing the dependency on ->bd_contains in
bd_may_claim(). As bd_may_claim() has direct access to the whole
device, it can simply test if the target bdev is the whole device.
Fixes: 6b4517a791 ("block: implement bd_claiming and claiming block")
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 52bce91165 upstream.
Commit 8924feff66 ("splice: lift pipe_lock out of splice_to_pipe()")
caused a regression when there were no more readers left on a pipe that
was being spliced into: rather than the expected SIGPIPE and -EPIPE
return value, the writer would end up waiting forever for space to free
up (which obviously was not going to happen with no readers around).
Fixes: 8924feff66 ("splice: lift pipe_lock out of splice_to_pipe()")
Reported-and-tested-by: Andreas Schwab <schwab@linux-m68k.org>
Debugged-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 613cc2b6f2 upstream.
If you have a process that has set itself to be non-dumpable, and it
then undergoes exec(2), any CLOEXEC file descriptors it has open are
"exposed" during a race window between the dumpable flags of the process
being reset for exec(2) and CLOEXEC being applied to the file
descriptors. This can be exploited by a process by attempting to access
/proc/<pid>/fd/... during this window, without requiring CAP_SYS_PTRACE.
The race in question is after set_dumpable has been (for get_link,
though the trace is basically the same for readlink):
[vfs]
-> proc_pid_link_inode_operations.get_link
-> proc_pid_get_link
-> proc_fd_access_allowed
-> ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS);
Which will return 0, during the race window and CLOEXEC file descriptors
will still be open during this window because do_close_on_exec has not
been called yet. As a result, the ordering of these calls should be
reversed to avoid this race window.
This is of particular concern to container runtimes, where joining a
PID namespace with file descriptors referring to the host filesystem
can result in security issues (since PRCTL_SET_DUMPABLE doesn't protect
against access of CLOEXEC file descriptors -- file descriptors which may
reference filesystem objects the container shouldn't have access to).
Cc: dev@opencontainers.org
Reported-by: Michael Crosby <crosbymichael@gmail.com>
Signed-off-by: Aleksa Sarai <asarai@suse.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f84df2a6f2 upstream.
When the user namespace support was merged the need to prevent
ptrace from revealing the contents of an unreadable executable
was overlooked.
Correct this oversight by ensuring that the executed file
or files are in mm->user_ns, by adjusting mm->user_ns.
Use the new function privileged_wrt_inode_uidgid to see if
the executable is a member of the user namespace, and as such
if having CAP_SYS_PTRACE in the user namespace should allow
tracing the executable. If not update mm->user_ns to
the parent user namespace until an appropriate parent is found.
Reported-by: Jann Horn <jann@thejh.net>
Fixes: 9e4a36ece6 ("userns: Fail exec for suid and sgid binaries with ids outside our user namespace.")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 8d9eddad19 upstream.
We were setting the qgroup_rescan_running flag to true only after the
rescan worker started (which is a task run by a queue). So if a user
space task starts a rescan and immediately after asks to wait for the
rescan worker to finish, this second call might happen before the rescan
worker task starts running, in which case the rescan wait ioctl returns
immediatley, not waiting for the rescan worker to finish.
This was making the fstest btrfs/022 fail very often.
Fixes: d2c609b834 (btrfs: properly track when rescan worker is running)
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit ed0df618b1 upstream.
The balance status item contains currently known filter values, but the
stripes filter was unintentionally not among them. This would mean, that
interrupted and automatically restarted balance does not apply the
stripe filters.
Fixes: dee32d0ac3
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 054570a1dc upstream.
During relocation of a data block group we create a relocation tree
for each fs/subvol tree by making a snapshot of each tree using
btrfs_copy_root() and the tree's commit root, and then setting the last
snapshot field for the fs/subvol tree's root to the value of the current
transaction id minus 1. However this can lead to relocation later
dropping references that it did not create if we have qgroups enabled,
leaving the filesystem in an inconsistent state that keeps aborting
transactions.
Lets consider the following example to explain the problem, which requires
qgroups to be enabled.
We are relocating data block group Y, we have a subvolume with id 258 that
has a root at level 1, that subvolume is used to store directory entries
for snapshots and we are currently at transaction 3404.
When committing transaction 3404, we have a pending snapshot and therefore
we call btrfs_run_delayed_items() at transaction.c:create_pending_snapshot()
in order to create its dentry at subvolume 258. This results in COWing
leaf A from root 258 in order to add the dentry. Note that leaf A
also contains file extent items referring to extents from some other
block group X (we are currently relocating block group Y). Later on, still
at create_pending_snapshot() we call qgroup_account_snapshot(), which
switches the commit root for root 258 when it calls switch_commit_roots(),
so now the COWed version of leaf A, lets call it leaf A', is accessible
from the commit root of tree 258. At the end of qgroup_account_snapshot(),
we call record_root_in_trans() with 258 as its argument, which results
in btrfs_init_reloc_root() being called, which in turn calls
relocation.c:create_reloc_root() in order to create a relocation tree
associated to root 258, which results in assigning the value of 3403
(which is the current transaction id minus 1 = 3404 - 1) to the
last_snapshot field of root 258. When creating the relocation tree root
at ctree.c:btrfs_copy_root() we add a shared reference for leaf A',
corresponding to the relocation tree's root, when we call btrfs_inc_ref()
against the COWed root (a copy of the commit root from tree 258), which
is at level 1. So at this point leaf A' has 2 references, one normal
reference corresponding to root 258 and one shared reference corresponding
to the root of the relocation tree.
Transaction 3404 finishes its commit and transaction 3405 is started by
relocation when calling merge_reloc_root() for the relocation tree
associated to root 258. In the meanwhile leaf A' is COWed again, in
response to some filesystem operation, when we are still at transaction
3405. However when we COW leaf A', at ctree.c:update_ref_for_cow(), we
call btrfs_block_can_be_shared() in order to figure out if other trees
refer to the leaf and if any such trees exists, add a full back reference
to leaf A' - but btrfs_block_can_be_shared() incorrectly returns false
because the following condition is false:
btrfs_header_generation(buf) <= btrfs_root_last_snapshot(&root->root_item)
which evaluates to 3404 <= 3403. So after leaf A' is COWed, it stays with
only one reference, corresponding to the shared reference we created when
we called btrfs_copy_root() to create the relocation tree's root and
btrfs_inc_ref() ends up not being called for leaf A' nor we end up setting
the flag BTRFS_BLOCK_FLAG_FULL_BACKREF in leaf A'. This results in not
adding shared references for the extents from block group X that leaf A'
refers to with its file extent items.
Later, after merging the relocation root we do a call to to
btrfs_drop_snapshot() in order to delete the relocation tree. This ends
up calling do_walk_down() when path->slots[1] points to leaf A', which
results in calling btrfs_lookup_extent_info() to get the number of
references for leaf A', which is 1 at this time (only the shared reference
exists) and this value is stored at wc->refs[0]. After this walk_up_proc()
is called when wc->level is 0 and path->nodes[0] corresponds to leaf A'.
Because the current level is 0 and wc->refs[0] is 1, it does call
btrfs_dec_ref() against leaf A', which results in removing the single
references that the extents from block group X have which are associated
to root 258 - the expectation was to have each of these extents with 2
references - one reference for root 258 and one shared reference related
to the root of the relocation tree, and so we would drop only the shared
reference (because leaf A' was supposed to have the flag
BTRFS_BLOCK_FLAG_FULL_BACKREF set).
This leaves the filesystem in an inconsistent state as we now have file
extent items in a subvolume tree that point to extents from block group X
without references in the extent tree. So later on when we try to decrement
the references for these extents, for example due to a file unlink operation,
truncate operation or overwriting ranges of a file, we fail because the
expected references do not exist in the extent tree.
This leads to warnings and transaction aborts like the following:
[ 588.965795] ------------[ cut here ]------------
[ 588.965815] WARNING: CPU: 2 PID: 2479 at fs/btrfs/extent-tree.c:1625 lookup_inline_extent_backref+0x432/0x5b0 [btrfs]
[ 588.965816] Modules linked in: af_packet iscsi_ibft iscsi_boot_sysfs xfs libcrc32c ppdev acpi_cpufreq button tpm_tis e1000 i2c_piix4 pcspkr parport_pc
parport tpm qemu_fw_cfg joydev btrfs xor raid6_pq sr_mod cdrom ata_generic virtio_scsi ata_piix virtio_pci bochs_drm virtio_ring drm_kms_helper syscopyarea
sysfillrect sysimgblt fb_sys_fops virtio ttm serio_raw drm floppy sg
[ 588.965831] CPU: 2 PID: 2479 Comm: kworker/u8:7 Not tainted 4.7.3-3-default-fdm+ #1
[ 588.965832] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.9.1-0-gb3ef39f-prebuilt.qemu-project.org 04/01/2014
[ 588.965844] Workqueue: btrfs-extent-refs btrfs_extent_refs_helper [btrfs]
[ 588.965845] 0000000000000000 ffff8802263bfa28 ffffffff813af542 0000000000000000
[ 588.965847] 0000000000000000 ffff8802263bfa68 ffffffff81081e8b 0000065900000000
[ 588.965848] ffff8801db2af000 000000012bbe2000 0000000000000000 ffff880215703b48
[ 588.965849] Call Trace:
[ 588.965852] [<ffffffff813af542>] dump_stack+0x63/0x81
[ 588.965854] [<ffffffff81081e8b>] __warn+0xcb/0xf0
[ 588.965855] [<ffffffff81081f7d>] warn_slowpath_null+0x1d/0x20
[ 588.965863] [<ffffffffa0175042>] lookup_inline_extent_backref+0x432/0x5b0 [btrfs]
[ 588.965865] [<ffffffff81143220>] ? trace_clock_local+0x10/0x30
[ 588.965867] [<ffffffff8114c5df>] ? rb_reserve_next_event+0x6f/0x460
[ 588.965875] [<ffffffffa0175215>] insert_inline_extent_backref+0x55/0xd0 [btrfs]
[ 588.965882] [<ffffffffa017531f>] __btrfs_inc_extent_ref.isra.55+0x8f/0x240 [btrfs]
[ 588.965890] [<ffffffffa017acea>] __btrfs_run_delayed_refs+0x74a/0x1260 [btrfs]
[ 588.965892] [<ffffffff810cb046>] ? cpuacct_charge+0x86/0xa0
[ 588.965900] [<ffffffffa017e74f>] btrfs_run_delayed_refs+0x9f/0x2c0 [btrfs]
[ 588.965908] [<ffffffffa017ea04>] delayed_ref_async_start+0x94/0xb0 [btrfs]
[ 588.965918] [<ffffffffa01c799a>] btrfs_scrubparity_helper+0xca/0x350 [btrfs]
[ 588.965928] [<ffffffffa01c7c5e>] btrfs_extent_refs_helper+0xe/0x10 [btrfs]
[ 588.965930] [<ffffffff8109b323>] process_one_work+0x1f3/0x4e0
[ 588.965931] [<ffffffff8109b658>] worker_thread+0x48/0x4e0
[ 588.965932] [<ffffffff8109b610>] ? process_one_work+0x4e0/0x4e0
[ 588.965934] [<ffffffff810a1659>] kthread+0xc9/0xe0
[ 588.965936] [<ffffffff816f2f1f>] ret_from_fork+0x1f/0x40
[ 588.965937] [<ffffffff810a1590>] ? kthread_worker_fn+0x170/0x170
[ 588.965938] ---[ end trace 34e5232c933a1749 ]---
[ 588.966187] ------------[ cut here ]------------
[ 588.966196] WARNING: CPU: 2 PID: 2479 at fs/btrfs/extent-tree.c:2966 btrfs_run_delayed_refs+0x28c/0x2c0 [btrfs]
[ 588.966196] BTRFS: Transaction aborted (error -5)
[ 588.966197] Modules linked in: af_packet iscsi_ibft iscsi_boot_sysfs xfs libcrc32c ppdev acpi_cpufreq button tpm_tis e1000 i2c_piix4 pcspkr parport_pc
parport tpm qemu_fw_cfg joydev btrfs xor raid6_pq sr_mod cdrom ata_generic virtio_scsi ata_piix virtio_pci bochs_drm virtio_ring drm_kms_helper syscopyarea
sysfillrect sysimgblt fb_sys_fops virtio ttm serio_raw drm floppy sg
[ 588.966206] CPU: 2 PID: 2479 Comm: kworker/u8:7 Tainted: G W 4.7.3-3-default-fdm+ #1
[ 588.966207] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.9.1-0-gb3ef39f-prebuilt.qemu-project.org 04/01/2014
[ 588.966217] Workqueue: btrfs-extent-refs btrfs_extent_refs_helper [btrfs]
[ 588.966217] 0000000000000000 ffff8802263bfc98 ffffffff813af542 ffff8802263bfce8
[ 588.966219] 0000000000000000 ffff8802263bfcd8 ffffffff81081e8b 00000b96345ee000
[ 588.966220] ffffffffa021ae1c ffff880215703b48 00000000000005fe ffff8802345ee000
[ 588.966221] Call Trace:
[ 588.966223] [<ffffffff813af542>] dump_stack+0x63/0x81
[ 588.966224] [<ffffffff81081e8b>] __warn+0xcb/0xf0
[ 588.966225] [<ffffffff81081eff>] warn_slowpath_fmt+0x4f/0x60
[ 588.966233] [<ffffffffa017e93c>] btrfs_run_delayed_refs+0x28c/0x2c0 [btrfs]
[ 588.966241] [<ffffffffa017ea04>] delayed_ref_async_start+0x94/0xb0 [btrfs]
[ 588.966250] [<ffffffffa01c799a>] btrfs_scrubparity_helper+0xca/0x350 [btrfs]
[ 588.966259] [<ffffffffa01c7c5e>] btrfs_extent_refs_helper+0xe/0x10 [btrfs]
[ 588.966260] [<ffffffff8109b323>] process_one_work+0x1f3/0x4e0
[ 588.966261] [<ffffffff8109b658>] worker_thread+0x48/0x4e0
[ 588.966263] [<ffffffff8109b610>] ? process_one_work+0x4e0/0x4e0
[ 588.966264] [<ffffffff810a1659>] kthread+0xc9/0xe0
[ 588.966265] [<ffffffff816f2f1f>] ret_from_fork+0x1f/0x40
[ 588.966267] [<ffffffff810a1590>] ? kthread_worker_fn+0x170/0x170
[ 588.966268] ---[ end trace 34e5232c933a174a ]---
[ 588.966269] BTRFS: error (device sda2) in btrfs_run_delayed_refs:2966: errno=-5 IO failure
[ 588.966270] BTRFS info (device sda2): forced readonly
This was happening often on openSUSE and SLE systems using btrfs as the
root filesystem (with its default layout where multiple subvolumes are
used) where balance happens in the background triggered by a cron job and
snapshots are automatically created before/after package installations,
upgrades and removals. The issue could be triggered simply by running the
following loop on the first system boot post installation:
while true; do
zypper -n in nfs-kernel-server
zypper -n rm nfs-kernel-server
done
(If we were fast enough and made that loop before the cron job triggered
a balance operation and the balance finished)
So fix by setting the last_snapshot field of the root to the value of the
generation of its commit root. Like this btrfs_block_can_be_shared()
behaves correctly for the case where the relocation root is created during
a transaction commit and for the case where it's created before a
transaction commit.
Fixes: 6426c7ad69 (btrfs: qgroup: Fix qgroup accounting when creating snapshot)
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 2a7bf53f57 upstream.
If a log tree has a layout like the following:
leaf N:
...
item 240 key (282 DIR_LOG_ITEM 0) itemoff 8189 itemsize 8
dir log end 1275809046
leaf N + 1:
item 0 key (282 DIR_LOG_ITEM 3936149215) itemoff 16275 itemsize 8
dir log end 18446744073709551615
...
When we pass the value 1275809046 + 1 as the parameter start_ret to the
function tree-log.c:find_dir_range() (done by replay_dir_deletes()), we
end up with path->slots[0] having the value 239 (points to the last item
of leaf N, item 240). Because the dir log item in that position has an
offset value smaller than *start_ret (1275809046 + 1) we need to move on
to the next leaf, however the logic for that is wrong since it compares
the current slot to the number of items in the leaf, which is smaller
and therefore we don't lookup for the next leaf but instead we set the
slot to point to an item that does not exist, at slot 240, and we later
operate on that slot which has unexpected content or in the worst case
can result in an invalid memory access (accessing beyond the last page
of leaf N's extent buffer).
So fix the logic that checks when we need to lookup at the next leaf
by first incrementing the slot and only after to check if that slot
is beyond the last item of the current leaf.
Signed-off-by: Robbie Ko <robbieko@synology.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Fixes: e02119d5a7 (Btrfs: Add a write ahead tree log to optimize synchronous operations)
Signed-off-by: Filipe Manana <fdmanana@suse.com>
[Modified changelog for clarity and correctness]
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
