- Fix a KMSAN uninit-value issue triggered by a crafted image;
- Fix VMA alignment for memory mapped files on THP.
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Merge tag 'erofs-for-6.8-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs
Pull erofs fixes from Gao Xiang:
"The main one is a KMSAN fix which addresses an issue introduced in
this cycle so it'd be much better to fix before releasing, and the
remaining one fixes VMA alignment for THP.
Summary:
- Fix a KMSAN uninit-value issue triggered by a crafted image
- Fix VMA alignment for memory mapped files on THP"
* tag 'erofs-for-6.8-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs:
erofs: apply proper VMA alignment for memory mapped files on THP
erofs: fix uninitialized page cache reported by KMSAN
There are mainly two reasons that thp_get_unmapped_area() should be
used for EROFS as other filesystems:
- It's needed to enable PMD mappings as a FSDAX filesystem, see
commit 74d2fad133 ("thp, dax: add thp_get_unmapped_area for pmd
mappings");
- It's useful together with large folios and
CONFIG_READ_ONLY_THP_FOR_FS which enable THPs for mmapped files
(e.g. shared libraries) even without FSDAX. See commit 1854bc6e24
("mm/readahead: Align file mappings for non-DAX").
Fixes: 06252e9ce0 ("erofs: dax support for non-tailpacking regular file")
Fixes: ce529cc25b ("erofs: enable large folios for iomap mode")
Fixes: e6687b8922 ("erofs: enable large folios for fscache mode")
Reviewed-by: Jingbo Xu <jefflexu@linux.alibaba.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20240306053138.2240206-1-hsiangkao@linux.alibaba.com
syzbot reports a KMSAN reproducer [1] which generates a crafted
filesystem image and causes IMA to read uninitialized page cache.
Later, (rq->outputsize > rq->inputsize) will be formally supported
after either large uncompressed pclusters (> block size) or big
lclusters are landed. However, currently there is no way to generate
such filesystems by using mkfs.erofs.
Thus, let's mark this condition as unsupported for now.
[1] https://lore.kernel.org/r/0000000000002be12a0611ca7ff8@google.com
Reported-and-tested-by: syzbot+7bc44a489f0ef0670bd5@syzkaller.appspotmail.com
Fixes: 1ca0152014 ("erofs: refine z_erofs_transform_plain() for sub-page block support")
Reviewed-by: Sandeep Dhavale <dhavale@google.com>
Reviewed-by: Yue Hu <huyue2@coolpad.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20240304035339.425857-1-hsiangkao@linux.alibaba.com
This flag is only set by one single user: the magical core dumping code
that looks up user pages one by one, and then writes them out using
their kernel addresses (by using a BVEC_ITER).
That actually ends up being a huge problem, because while we do use
copy_mc_to_kernel() for this case and it is able to handle the possible
machine checks involved, nothing else is really ready to handle the
failures caused by the machine check.
In particular, as reported by Tong Tiangen, we don't actually support
fault_in_iov_iter_readable() on a machine check area.
As a result, the usual logic for writing things to a file under a
filesystem lock, which involves doing a copy with page faults disabled
and then if that fails trying to fault pages in without holding the
locks with fault_in_iov_iter_readable() does not work at all.
We could decide to always just make the MC copy "succeed" (and filling
the destination with zeroes), and that would then create a core dump
file that just ignores any machine checks.
But honestly, this single special case has been problematic before, and
means that all the normal iov_iter code ends up slightly more complex
and slower.
See for example commit c9eec08bac ("iov_iter: Don't deal with
iter->copy_mc in memcpy_from_iter_mc()") where David Howells
re-organized the code just to avoid having to check the 'copy_mc' flags
inside the inner iov_iter loops.
So considering that we have exactly one user, and that one user is a
non-critical special case that doesn't actually ever trigger in real
life (Tong found this with manual error injection), the sane solution is
to just decide that the onus on handling the machine check lines on that
user instead.
Ergo, do the copy_mc_to_kernel() in the core dump logic itself, copying
the user data to a stable kernel page before writing it out.
Fixes: f1982740f5 ("iov_iter: Convert iterate*() to inline funcs")
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Tong Tiangen <tongtiangen@huawei.com>
Link: https://lore.kernel.org/r/20240305133336.3804360-1-tongtiangen@huawei.com
Link: https://lore.kernel.org/all/4e80924d-9c85-f13a-722a-6a5d2b1c225a@huawei.com/
Tested-by: David Howells <dhowells@redhat.com>
Reviewed-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Reported-by: Tong Tiangen <tongtiangen@huawei.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
The first kiocb_set_cancel_fn() argument may point at a struct kiocb
that is not embedded inside struct aio_kiocb. With the current code,
depending on the compiler, the req->ki_ctx read happens either before
the IOCB_AIO_RW test or after that test. Move the req->ki_ctx read such
that it is guaranteed that the IOCB_AIO_RW test happens first.
Reported-by: Eric Biggers <ebiggers@kernel.org>
Cc: Benjamin LaHaise <ben@communityfibre.ca>
Cc: Eric Biggers <ebiggers@google.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Avi Kivity <avi@scylladb.com>
Cc: Sandeep Dhavale <dhavale@google.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Kent Overstreet <kent.overstreet@linux.dev>
Cc: stable@vger.kernel.org
Fixes: b820de741a ("fs/aio: Restrict kiocb_set_cancel_fn() to I/O submitted via libaio")
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20240304235715.3790858-1-bvanassche@acm.org
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Patch "fs/aio: Make io_cancel() generate completions again" is based on the
assumption that calling kiocb->ki_cancel() does not complete R/W requests.
This is incorrect: the two drivers that call kiocb_set_cancel_fn() callers
set a cancellation function that calls usb_ep_dequeue(). According to its
documentation, usb_ep_dequeue() calls the completion routine with status
-ECONNRESET. Hence this revert.
Cc: Benjamin LaHaise <ben@communityfibre.ca>
Cc: Eric Biggers <ebiggers@google.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Avi Kivity <avi@scylladb.com>
Cc: Sandeep Dhavale <dhavale@google.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Kent Overstreet <kent.overstreet@linux.dev>
Cc: stable@vger.kernel.org
Reported-by: syzbot+b91eb2ed18f599dd3c31@syzkaller.appspotmail.com
Fixes: 54cbc058d8 ("fs/aio: Make io_cancel() generate completions again")
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20240304182945.3646109-1-bvanassche@acm.org
Acked-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
* Drop experimental warning for FSDAX.
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
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Merge tag 'xfs-6.8-fixes-4' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux
Pull xfs fix from Chandan Babu:
"Drop experimental warning message when mounting an xfs filesystem on
an fsdax device. We now consider xfs on fsdax to be stable"
* tag 'xfs-6.8-fixes-4' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
xfs: drop experimental warning for FSDAX
being necessary after all to enable cluster upgrades from problematic
v18.2.0 and v18.2.1 releases.
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Merge tag 'ceph-for-6.8-rc7' of https://github.com/ceph/ceph-client
Pull ceph fix from Ilya Dryomov:
"Catch up with mdsmap encoding rectification which ended up being
necessary after all to enable cluster upgrades from problematic
v18.2.0 and v18.2.1 releases"
* tag 'ceph-for-6.8-rc7' of https://github.com/ceph/ceph-client:
ceph: switch to corrected encoding of max_xattr_size in mdsmap
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Merge tag 'for-6.8-rc6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs fixes from David Sterba:
- fix freeing allocated id for anon dev when snapshot creation fails
- fiemap fixes:
- followup for a recent deadlock fix, ranges that fiemap can access
can still race with ordered extent completion
- make sure fiemap with SYNC flag does not race with writes
* tag 'for-6.8-rc6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
btrfs: fix double free of anonymous device after snapshot creation failure
btrfs: ensure fiemap doesn't race with writes when FIEMAP_FLAG_SYNC is given
btrfs: fix race between ordered extent completion and fiemap
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Merge tag 'vfs-6.8-rc7.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull vfs fixes from Christian Brauner:
"Two small fixes:
- Fix an endless loop during afs directory iteration caused by not
skipping silly-rename files correctly.
- Fix reporting of completion events for aio causing leaks in
userspace. This is based on the fix last week as it's now possible
to recognize aio events submitted through the old aio interface"
* tag 'vfs-6.8-rc7.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
fs/aio: Make io_cancel() generate completions again
afs: Fix endless loop in directory parsing
- Fix phys_addr_t size confusion in 32-bit capsule loader
- Reduce maximum EFI variable name size to 512 to work around buggy
firmware
- Drop some redundant code from efivarfs while at it
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Merge tag 'efi-fixes-for-v6.8-2' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi
Pull EFI fixes from Ard Biesheuvel:
"Only the EFI variable name size change is significant, and will be
backported once it lands. The others are cleanup.
- Fix phys_addr_t size confusion in 32-bit capsule loader
- Reduce maximum EFI variable name size to 512 to work around buggy
firmware
- Drop some redundant code from efivarfs while at it"
* tag 'efi-fixes-for-v6.8-2' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi:
efivarfs: Drop 'duplicates' bool parameter on efivar_init()
efivarfs: Drop redundant cleanup on fill_super() failure
efivarfs: Request at most 512 bytes for variable names
efi/capsule-loader: fix incorrect allocation size
When creating a snapshot we may do a double free of an anonymous device
in case there's an error committing the transaction. The second free may
result in freeing an anonymous device number that was allocated by some
other subsystem in the kernel or another btrfs filesystem.
The steps that lead to this:
1) At ioctl.c:create_snapshot() we allocate an anonymous device number
and assign it to pending_snapshot->anon_dev;
2) Then we call btrfs_commit_transaction() and end up at
transaction.c:create_pending_snapshot();
3) There we call btrfs_get_new_fs_root() and pass it the anonymous device
number stored in pending_snapshot->anon_dev;
4) btrfs_get_new_fs_root() frees that anonymous device number because
btrfs_lookup_fs_root() returned a root - someone else did a lookup
of the new root already, which could some task doing backref walking;
5) After that some error happens in the transaction commit path, and at
ioctl.c:create_snapshot() we jump to the 'fail' label, and after
that we free again the same anonymous device number, which in the
meanwhile may have been reallocated somewhere else, because
pending_snapshot->anon_dev still has the same value as in step 1.
Recently syzbot ran into this and reported the following trace:
------------[ cut here ]------------
ida_free called for id=51 which is not allocated.
WARNING: CPU: 1 PID: 31038 at lib/idr.c:525 ida_free+0x370/0x420 lib/idr.c:525
Modules linked in:
CPU: 1 PID: 31038 Comm: syz-executor.2 Not tainted 6.8.0-rc4-syzkaller-00410-gc02197fc9076 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
RIP: 0010:ida_free+0x370/0x420 lib/idr.c:525
Code: 10 42 80 3c 28 (...)
RSP: 0018:ffffc90015a67300 EFLAGS: 00010246
RAX: be5130472f5dd000 RBX: 0000000000000033 RCX: 0000000000040000
RDX: ffffc90009a7a000 RSI: 000000000003ffff RDI: 0000000000040000
RBP: ffffc90015a673f0 R08: ffffffff81577992 R09: 1ffff92002b4cdb4
R10: dffffc0000000000 R11: fffff52002b4cdb5 R12: 0000000000000246
R13: dffffc0000000000 R14: ffffffff8e256b80 R15: 0000000000000246
FS: 00007fca3f4b46c0(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f167a17b978 CR3: 000000001ed26000 CR4: 0000000000350ef0
Call Trace:
<TASK>
btrfs_get_root_ref+0xa48/0xaf0 fs/btrfs/disk-io.c:1346
create_pending_snapshot+0xff2/0x2bc0 fs/btrfs/transaction.c:1837
create_pending_snapshots+0x195/0x1d0 fs/btrfs/transaction.c:1931
btrfs_commit_transaction+0xf1c/0x3740 fs/btrfs/transaction.c:2404
create_snapshot+0x507/0x880 fs/btrfs/ioctl.c:848
btrfs_mksubvol+0x5d0/0x750 fs/btrfs/ioctl.c:998
btrfs_mksnapshot+0xb5/0xf0 fs/btrfs/ioctl.c:1044
__btrfs_ioctl_snap_create+0x387/0x4b0 fs/btrfs/ioctl.c:1306
btrfs_ioctl_snap_create_v2+0x1ca/0x400 fs/btrfs/ioctl.c:1393
btrfs_ioctl+0xa74/0xd40
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:871 [inline]
__se_sys_ioctl+0xfe/0x170 fs/ioctl.c:857
do_syscall_64+0xfb/0x240
entry_SYSCALL_64_after_hwframe+0x6f/0x77
RIP: 0033:0x7fca3e67dda9
Code: 28 00 00 00 (...)
RSP: 002b:00007fca3f4b40c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fca3e7abf80 RCX: 00007fca3e67dda9
RDX: 00000000200005c0 RSI: 0000000050009417 RDI: 0000000000000003
RBP: 00007fca3e6ca47a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007fca3e7abf80 R15: 00007fff6bf95658
</TASK>
Where we get an explicit message where we attempt to free an anonymous
device number that is not currently allocated. It happens in a different
code path from the example below, at btrfs_get_root_ref(), so this change
may not fix the case triggered by syzbot.
To fix at least the code path from the example above, change
btrfs_get_root_ref() and its callers to receive a dev_t pointer argument
for the anonymous device number, so that in case it frees the number, it
also resets it to 0, so that up in the call chain we don't attempt to do
the double free.
CC: stable@vger.kernel.org # 5.10+
Link: https://lore.kernel.org/linux-btrfs/000000000000f673a1061202f630@google.com/
Fixes: e03ee2fe87 ("btrfs: do not ASSERT() if the newly created subvolume already got read")
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When FIEMAP_FLAG_SYNC is given to fiemap the expectation is that that
are no concurrent writes and we get a stable view of the inode's extent
layout.
When the flag is given we flush all IO (and wait for ordered extents to
complete) and then lock the inode in shared mode, however that leaves open
the possibility that a write might happen right after the flushing and
before locking the inode. So fix this by flushing again after locking the
inode - we leave the initial flushing before locking the inode to avoid
holding the lock and blocking other RO operations while waiting for IO
and ordered extents to complete. The second flushing while holding the
inode's lock will most of the time do nothing or very little since the
time window for new writes to have happened is small.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
For fiemap we recently stopped locking the target extent range for the
whole duration of the fiemap call, in order to avoid a deadlock in a
scenario where the fiemap buffer happens to be a memory mapped range of
the same file. This use case is very unlikely to be useful in practice but
it may be triggered by fuzz testing (syzbot, etc).
However by not locking the target extent range for the whole duration of
the fiemap call we can race with an ordered extent. This happens like
this:
1) The fiemap task finishes processing a file extent item that covers
the file range [512K, 1M[, and that file extent item is the last item
in the leaf currently being processed;
2) And ordered extent for the file range [768K, 2M[, in COW mode,
completes (btrfs_finish_one_ordered()) and the file extent item
covering the range [512K, 1M[ is trimmed to cover the range
[512K, 768K[ and then a new file extent item for the range [768K, 2M[
is inserted in the inode's subvolume tree;
3) The fiemap task calls fiemap_next_leaf_item(), which then calls
btrfs_next_leaf() to find the next leaf / item. This finds that the
the next key following the one we previously processed (its type is
BTRFS_EXTENT_DATA_KEY and its offset is 512K), is the key corresponding
to the new file extent item inserted by the ordered extent, which has
a type of BTRFS_EXTENT_DATA_KEY and an offset of 768K;
4) Later the fiemap code ends up at emit_fiemap_extent() and triggers
the warning:
if (cache->offset + cache->len > offset) {
WARN_ON(1);
return -EINVAL;
}
Since we get 1M > 768K, because the previously emitted entry for the
old extent covering the file range [512K, 1M[ ends at an offset that
is greater than the new extent's start offset (768K). This makes fiemap
fail with -EINVAL besides triggering the warning that produces a stack
trace like the following:
[1621.677651] ------------[ cut here ]------------
[1621.677656] WARNING: CPU: 1 PID: 204366 at fs/btrfs/extent_io.c:2492 emit_fiemap_extent+0x84/0x90 [btrfs]
[1621.677899] Modules linked in: btrfs blake2b_generic (...)
[1621.677951] CPU: 1 PID: 204366 Comm: pool Not tainted 6.8.0-rc5-btrfs-next-151+ #1
[1621.677954] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.2-0-gea1b7a073390-prebuilt.qemu.org 04/01/2014
[1621.677956] RIP: 0010:emit_fiemap_extent+0x84/0x90 [btrfs]
[1621.678033] Code: 2b 4c 89 63 (...)
[1621.678035] RSP: 0018:ffffab16089ffd20 EFLAGS: 00010206
[1621.678037] RAX: 00000000004fa000 RBX: ffffab16089ffe08 RCX: 0000000000009000
[1621.678039] RDX: 00000000004f9000 RSI: 00000000004f1000 RDI: ffffab16089ffe90
[1621.678040] RBP: 00000000004f9000 R08: 0000000000001000 R09: 0000000000000000
[1621.678041] R10: 0000000000000000 R11: 0000000000001000 R12: 0000000041d78000
[1621.678043] R13: 0000000000001000 R14: 0000000000000000 R15: ffff9434f0b17850
[1621.678044] FS: 00007fa6e20006c0(0000) GS:ffff943bdfa40000(0000) knlGS:0000000000000000
[1621.678046] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[1621.678048] CR2: 00007fa6b0801000 CR3: 000000012d404002 CR4: 0000000000370ef0
[1621.678053] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[1621.678055] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[1621.678056] Call Trace:
[1621.678074] <TASK>
[1621.678076] ? __warn+0x80/0x130
[1621.678082] ? emit_fiemap_extent+0x84/0x90 [btrfs]
[1621.678159] ? report_bug+0x1f4/0x200
[1621.678164] ? handle_bug+0x42/0x70
[1621.678167] ? exc_invalid_op+0x14/0x70
[1621.678170] ? asm_exc_invalid_op+0x16/0x20
[1621.678178] ? emit_fiemap_extent+0x84/0x90 [btrfs]
[1621.678253] extent_fiemap+0x766/0xa30 [btrfs]
[1621.678339] btrfs_fiemap+0x45/0x80 [btrfs]
[1621.678420] do_vfs_ioctl+0x1e4/0x870
[1621.678431] __x64_sys_ioctl+0x6a/0xc0
[1621.678434] do_syscall_64+0x52/0x120
[1621.678445] entry_SYSCALL_64_after_hwframe+0x6e/0x76
There's also another case where before calling btrfs_next_leaf() we are
processing a hole or a prealloc extent and we had several delalloc ranges
within that hole or prealloc extent. In that case if the ordered extents
complete before we find the next key, we may end up finding an extent item
with an offset smaller than (or equals to) the offset in cache->offset.
So fix this by changing emit_fiemap_extent() to address these three
scenarios like this:
1) For the first case, steps listed above, adjust the length of the
previously cached extent so that it does not overlap with the current
extent, emit the previous one and cache the current file extent item;
2) For the second case where he had a hole or prealloc extent with
multiple delalloc ranges inside the hole or prealloc extent's range,
and the current file extent item has an offset that matches the offset
in the fiemap cache, just discard what we have in the fiemap cache and
assign the current file extent item to the cache, since it's more up
to date;
3) For the third case where he had a hole or prealloc extent with
multiple delalloc ranges inside the hole or prealloc extent's range
and the offset of the file extent item we just found is smaller than
what we have in the cache, just skip the current file extent item
if its range end at or behind the cached extent's end, because we may
have emitted (to the fiemap user space buffer) delalloc ranges that
overlap with the current file extent item's range. If the file extent
item's range goes beyond the end offset of the cached extent, just
emit the cached extent and cache a subrange of the file extent item,
that goes from the end offset of the cached extent to the end offset
of the file extent item.
Dealing with those cases in those ways makes everything consistent by
reflecting the current state of file extent items in the btree and
without emitting extents that have overlapping ranges (which would be
confusing and violating expectations).
This issue could be triggered often with test case generic/561, and was
also hit and reported by Wang Yugui.
Reported-by: Wang Yugui <wangyugui@e16-tech.com>
Link: https://lore.kernel.org/linux-btrfs/20240223104619.701F.409509F4@e16-tech.com/
Fixes: b0ad381fa7 ("btrfs: fix deadlock with fiemap and extent locking")
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The following patch accidentally removed the code for delivering
completions for cancelled reads and writes to user space: "[PATCH 04/33]
aio: remove retry-based AIO"
(https://lore.kernel.org/all/1363883754-27966-5-git-send-email-koverstreet@google.com/)
>From that patch:
- if (kiocbIsCancelled(iocb)) {
- ret = -EINTR;
- aio_complete(iocb, ret, 0);
- /* must not access the iocb after this */
- goto out;
- }
This leads to a leak in user space of a struct iocb. Hence this patch
that restores the code that reports to user space that a read or write
has been cancelled successfully.
Fixes: 41003a7bcf ("aio: remove retry-based AIO")
Cc: Christoph Hellwig <hch@lst.de>
Cc: Avi Kivity <avi@scylladb.com>
Cc: Sandeep Dhavale <dhavale@google.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Kent Overstreet <kent.overstreet@linux.dev>
Cc: stable@vger.kernel.org
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20240215204739.2677806-3-bvanassche@acm.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
If a directory has a block with only ".__afsXXXX" files in it (from
uncompleted silly-rename), these .__afsXXXX files are skipped but without
advancing the file position in the dir_context. This leads to
afs_dir_iterate() repeating the block again and again.
Fix this by making the code that skips the .__afsXXXX file also manually
advance the file position.
The symptoms are a soft lookup:
watchdog: BUG: soft lockup - CPU#3 stuck for 52s! [check:5737]
...
RIP: 0010:afs_dir_iterate_block+0x39/0x1fd
...
? watchdog_timer_fn+0x1a6/0x213
...
? asm_sysvec_apic_timer_interrupt+0x16/0x20
? afs_dir_iterate_block+0x39/0x1fd
afs_dir_iterate+0x10a/0x148
afs_readdir+0x30/0x4a
iterate_dir+0x93/0xd3
__do_sys_getdents64+0x6b/0xd4
This is almost certainly the actual fix for:
https://bugzilla.kernel.org/show_bug.cgi?id=218496
Fixes: 57e9d49c54 ("afs: Hide silly-rename files from userspace")
Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/r/786185.1708694102@warthog.procyon.org.uk
Reviewed-by: Marc Dionne <marc.dionne@auristor.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Markus Suvanto <markus.suvanto@gmail.com>
cc: linux-afs@lists.infradead.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
FSDAX and reflink can work together now, let's drop this warning.
Signed-off-by: Shiyang Ruan <ruansy.fnst@fujitsu.com>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
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Merge tag 'for-6.8-rc6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs fixes from David Sterba:
"A more fixes for recently reported or discovered problems:
- fix corner case of send that would generate potentially large
stream of zeros if there's a hole at the end of the file
- fix chunk validation in zoned mode on conventional zones, it was
possible to create chunks that would not be allowed on sequential
zones
- fix validation of dev-replace ioctl filenames
- fix KCSAN warnings about access to block reserve struct members"
* tag 'for-6.8-rc6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
btrfs: fix data race at btrfs_use_block_rsv() when accessing block reserve
btrfs: fix data races when accessing the reserved amount of block reserves
btrfs: send: don't issue unnecessary zero writes for trailing hole
btrfs: dev-replace: properly validate device names
btrfs: zoned: don't skip block group profile checks on conventional zones
The addition of bal_rank_mask with encoding version 17 was merged
into ceph.git in Oct 2022 and made it into v18.2.0 release normally.
A few months later, the much delayed addition of max_xattr_size got
merged, also with encoding version 17, placed before bal_rank_mask
in the encoding -- but it didn't make v18.2.0 release.
The way this ended up being resolved on the MDS side is that
bal_rank_mask will continue to be encoded in version 17 while
max_xattr_size is now encoded in version 18. This does mean that
older kernels will misdecode version 17, but this is also true for
v18.2.0 and v18.2.1 clients in userspace.
The best we can do is backport this adjustment -- see ceph.git
commit 78abfeaff27fee343fb664db633de5b221699a73 for details.
[ idryomov: changelog ]
Cc: stable@vger.kernel.org
Link: https://tracker.ceph.com/issues/64440
Fixes: d93231a6bc ("ceph: prevent a client from exceeding the MDS maximum xattr size")
Signed-off-by: Xiubo Li <xiubli@redhat.com>
Reviewed-by: Patrick Donnelly <pdonnell@ibm.com>
Reviewed-by: Venky Shankar <vshankar@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
When CONFIG_NTFS3_LZX_XPRESS is not set then we get the following build
error:
fs/ntfs3/frecord.c:2460:16: error: unused variable ‘i_size’
Signed-off-by: Mark O'Donovan <shiftee@posteo.net>
Fixes: 4fd6c08a16 ("fs/ntfs3: Use i_size_read and i_size_write")
Tested-by: Chris Clayton <chris2553@googlemail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Some more mostly boring fixes, but some not
User reported ones:
- the BTREE_ITER_FILTER_SNAPSHOTS one fixes a really nasty performance
bug; user reported an unter initially taking 2 seconds and then ~2
minutes
- kill a __GFP_NOFAIL in the buffered read path; this was a leftover
from the trickier fix to kill __GFP_NOFAIL in readahead, where we
can't return errors (and have to silently truncate the read
ourselves).
bcachefs can't use GFP_NOFAIL for folio state unlike iomap based
filesystems because our folio state is just barely too big, 2MB
hugepages cause us to exceed the 2 page threshhold for GFP_NOFAIL.
additionally, the flags argument was just buggy, we weren't supplying
GFP_KERNEL previously (!).
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Merge tag 'bcachefs-2024-02-25' of https://evilpiepirate.org/git/bcachefs
Pull bcachefs fixes from Kent Overstreet:
"Some more mostly boring fixes, but some not
User reported ones:
- the BTREE_ITER_FILTER_SNAPSHOTS one fixes a really nasty
performance bug; user reported an untar initially taking two
seconds and then ~2 minutes
- kill a __GFP_NOFAIL in the buffered read path; this was a leftover
from the trickier fix to kill __GFP_NOFAIL in readahead, where we
can't return errors (and have to silently truncate the read
ourselves).
bcachefs can't use GFP_NOFAIL for folio state unlike iomap based
filesystems because our folio state is just barely too big, 2MB
hugepages cause us to exceed the 2 page threshhold for GFP_NOFAIL.
additionally, the flags argument was just buggy, we weren't
supplying GFP_KERNEL previously (!)"
* tag 'bcachefs-2024-02-25' of https://evilpiepirate.org/git/bcachefs:
bcachefs: fix bch2_save_backtrace()
bcachefs: Fix check_snapshot() memcpy
bcachefs: Fix bch2_journal_flush_device_pins()
bcachefs: fix iov_iter count underflow on sub-block dio read
bcachefs: Fix BTREE_ITER_FILTER_SNAPSHOTS on inodes btree
bcachefs: Kill __GFP_NOFAIL in buffered read path
bcachefs: fix backpointer_to_text() when dev does not exist
- Fix page refcount leak when looking up specific inodes
introduced by metabuf reworking.
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Merge tag 'erofs-for-6.8-rc6-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs
Pull erofs fix from Gao Xiang:
- Fix page refcount leak when looking up specific inodes
introduced by metabuf reworking
* tag 'erofs-for-6.8-rc6-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs:
erofs: fix refcount on the metabuf used for inode lookup
pathwalk. This series is a result of code audit (the second round
of it) and it should deal with most of that stuff. Exceptions: ntfs3
->d_hash()/->d_compare() and ceph_d_revalidate(). Up to maintainers (a
note for NTFS folks - when documentation says that a method may not block,
it *does* imply that blocking allocations are to be avoided. Really).
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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Merge tag 'pull-fixes.pathwalk-rcu-2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull RCU pathwalk fixes from Al Viro:
"We still have some races in filesystem methods when exposed to RCU
pathwalk. This series is a result of code audit (the second round of
it) and it should deal with most of that stuff.
Still pending: ntfs3 ->d_hash()/->d_compare() and ceph_d_revalidate().
Up to maintainers (a note for NTFS folks - when documentation says
that a method may not block, it *does* imply that blocking allocations
are to be avoided. Really)"
[ More explanations for people who aren't familiar with the vagaries of
RCU path walking: most of it is hidden from filesystems, but if a
filesystem actively participates in the low-level path walking it
needs to make sure the fields involved in that walk are RCU-safe.
That "actively participate in low-level path walking" includes things
like having its own ->d_hash()/->d_compare() routines, or by having
its own directory permission function that doesn't just use the common
helpers. Having a ->d_revalidate() function will also have this issue.
Note that instead of making everything RCU safe you can also choose to
abort the RCU pathwalk if your operation cannot be done safely under
RCU, but that obviously comes with a performance penalty. One common
pattern is to allow the simple cases under RCU, and abort only if you
need to do something more complicated.
So not everything needs to be RCU-safe, and things like the inode etc
that the VFS itself maintains obviously already are. But these fixes
tend to be about properly RCU-delaying things like ->s_fs_info that
are maintained by the filesystem and that got potentially released too
early. - Linus ]
* tag 'pull-fixes.pathwalk-rcu-2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
ext4_get_link(): fix breakage in RCU mode
cifs_get_link(): bail out in unsafe case
fuse: fix UAF in rcu pathwalks
procfs: make freeing proc_fs_info rcu-delayed
procfs: move dropping pde and pid from ->evict_inode() to ->free_inode()
nfs: fix UAF on pathwalk running into umount
nfs: make nfs_set_verifier() safe for use in RCU pathwalk
afs: fix __afs_break_callback() / afs_drop_open_mmap() race
hfsplus: switch to rcu-delayed unloading of nls and freeing ->s_fs_info
exfat: move freeing sbi, upcase table and dropping nls into rcu-delayed helper
affs: free affs_sb_info with kfree_rcu()
rcu pathwalk: prevent bogus hard errors from may_lookup()
fs/super.c: don't drop ->s_user_ns until we free struct super_block itself
and a fix for erofs failure exit breakage (had been there since
way back).
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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Merge tag 'pull-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs fixes from Al Viro:
"A couple of fixes - revert of regression from this cycle and a fix for
erofs failure exit breakage (had been there since way back)"
* tag 'pull-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
erofs: fix handling kern_mount() failure
Revert "get rid of DCACHE_GENOCIDE"
The 'duplicates' bool argument is always true when efivar_init() is
called from its only caller so let's just drop it instead.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Al points out that kill_sb() will be called if efivarfs_fill_super()
fails and so there is no point in cleaning up the efivar entry list.
Reported-by: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Work around a quirk in a few old (2011-ish) UEFI implementations, where
a call to `GetNextVariableName` with a buffer size larger than 512 bytes
will always return EFI_INVALID_PARAMETER.
There is some lore around EFI variable names being up to 1024 bytes in
size, but this has no basis in the UEFI specification, and the upper
bounds are typically platform specific, and apply to the entire variable
(name plus payload).
Given that Linux does not permit creating files with names longer than
NAME_MAX (255) bytes, 512 bytes (== 256 UTF-16 characters) is a
reasonable limit.
Cc: <stable@vger.kernel.org> # 6.1+
Signed-off-by: Tim Schumacher <timschumi@gmx.de>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
1) errors from ext4_getblk() should not be propagated to caller
unless we are really sure that we would've gotten the same error
in non-RCU pathwalk.
2) we leak buffer_heads if ext4_getblk() is successful, but bh is
not uptodate.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
->d_revalidate() bails out there, anyway. It's not enough
to prevent getting into ->get_link() in RCU mode, but that
could happen only in a very contrieved setup. Not worth
trying to do anything fancy here unless ->d_revalidate()
stops kicking out of RCU mode at least in some cases.
Reviewed-by: Christian Brauner <brauner@kernel.org>
Acked-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
->permission(), ->get_link() and ->inode_get_acl() might dereference
->s_fs_info (and, in case of ->permission(), ->s_fs_info->fc->user_ns
as well) when called from rcu pathwalk.
Freeing ->s_fs_info->fc is rcu-delayed; we need to make freeing ->s_fs_info
and dropping ->user_ns rcu-delayed too.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
makes proc_pid_ns() safe from rcu pathwalk (put_pid_ns()
is still synchronous, but that's not a problem - it does
rcu-delay everything that needs to be)
Reviewed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
that keeps both around until struct inode is freed, making access
to them safe from rcu-pathwalk
Acked-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
NFS ->d_revalidate(), ->permission() and ->get_link() need to access
some parts of nfs_server when called in RCU mode:
server->flags
server->caps
*(server->io_stats)
and, worst of all, call
server->nfs_client->rpc_ops->have_delegation
(the last one - as NFS_PROTO(inode)->have_delegation()). We really
don't want to RCU-delay the entire nfs_free_server() (it would have
to be done with schedule_work() from RCU callback, since it can't
be made to run from interrupt context), but actual freeing of
nfs_server and ->io_stats can be done via call_rcu() just fine.
nfs_client part is handled simply by making nfs_free_client() use
kfree_rcu().
Acked-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
nfs_set_verifier() relies upon dentry being pinned; if that's
the case, grabbing ->d_lock stabilizes ->d_parent and guarantees
that ->d_parent points to a positive dentry. For something
we'd run into in RCU mode that is *not* true - dentry might've
been through dentry_kill() just as we grabbed ->d_lock, with
its parent going through the same just as we get to into
nfs_set_verifier_locked(). It might get to detaching inode
(and zeroing ->d_inode) before nfs_set_verifier_locked() gets
to fetching that; we get an oops as the result.
That can happen in nfs{,4} ->d_revalidate(); the call chain in
question is nfs_set_verifier_locked() <- nfs_set_verifier() <-
nfs_lookup_revalidate_delegated() <- nfs{,4}_do_lookup_revalidate().
We have checked that the parent had been positive, but that's
done before we get to nfs_set_verifier() and it's possible for
memory pressure to pick our dentry as eviction candidate by that
time. If that happens, back-to-back attempts to kill dentry and
its parent are quite normal. Sure, in case of eviction we'll
fail the ->d_seq check in the caller, but we need to survive
until we return there...
Acked-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
In __afs_break_callback() we might check ->cb_nr_mmap and if it's non-zero
do queue_work(&vnode->cb_work). In afs_drop_open_mmap() we decrement
->cb_nr_mmap and do flush_work(&vnode->cb_work) if it reaches zero.
The trouble is, there's nothing to prevent __afs_break_callback() from
seeing ->cb_nr_mmap before the decrement and do queue_work() after both
the decrement and flush_work(). If that happens, we might be in trouble -
vnode might get freed before the queued work runs.
__afs_break_callback() is always done under ->cb_lock, so let's make
sure that ->cb_nr_mmap can change from non-zero to zero while holding
->cb_lock (the spinlock component of it - it's a seqlock and we don't
need to mess with the counter).
Acked-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
->d_hash() and ->d_compare() use those, so we need to delay freeing
them.
Reviewed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
That stuff can be accessed by ->d_hash()/->d_compare(); as it is, we have
a hard-to-hit UAF if rcu pathwalk manages to get into ->d_hash() on a filesystem
that is in process of getting shut down.
Besides, having nls and upcase table cleanup moved from ->put_super() towards
the place where sbi is freed makes for simpler failure exits.
Acked-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
one of the flags in it is used by ->d_hash()/->d_compare()
Reviewed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
If lazy call of ->permission() returns a hard error, check that
try_to_unlazy() succeeds before returning it. That both makes
life easier for ->permission() instances and closes the race
in ENOTDIR handling - it is possible that positive d_can_lookup()
seen in link_path_walk() applies to the state *after* unlink() +
mkdir(), while nd->inode matches the state prior to that.
Normally seeing e.g. EACCES from permission check in rcu pathwalk
means that with some timings non-rcu pathwalk would've run into
the same; however, running into a non-executable regular file
in the middle of a pathname would not get to permission check -
it would fail with ENOTDIR instead.
Reviewed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Avoids fun races in RCU pathwalk... Same goes for freeing LSM shite
hanging off super_block's arse.
Reviewed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
check_snapshot() copies the bch_snapshot to a temporary to easily handle
older versions that don't have all the fields of the current version,
but it lacked a min() to correctly handle keys newer and larger than the
current version.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
If a journal write errored, the list of devices it was written to could
be empty - we're not supposed to mark an empty replicas list.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
bch2_direct_IO_read() checks the request offset and size for sector
alignment and then falls through to a couple calculations to shrink
the size of the request based on the inode size. The problem is that
these checks round up to the fs block size, which runs the risk of
underflowing iter->count if the block size happens to be large
enough. This is triggered by fstest generic/361 with a 4k block
size, which subsequently leads to a crash. To avoid this crash,
check that the shorten length doesn't exceed the overall length of
the iter.
Fixes:
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Su Yue <glass.su@suse.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
If we're in FILTER_SNAPSHOTS mode and we start scanning a range of the
keyspace where no keys are visible in the current snapshot, we have a
problem - we'll scan for a very long time before scanning terminates.
Awhile back, this was fixed for most cases with peek_upto() (and
assertions that enforce that it's being used).
But the fix missed the fact that the inodes btree is different - every
key offset is in a different snapshot tree, not just the inode field.
Fixes:
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Recently, we fixed our __GFP_NOFAIL usage in the readahead path, but the
easy one in read_single_folio() (where wa can return an error) was
missed - oops.
Fixes:
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
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Merge tag 'vfs-6.8-rc6.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull vfs fixes from Christian Brauner:
- Fix a memory leak in cachefiles
- Restrict aio cancellations to I/O submitted through the aio
interfaces as this is otherwise causing issues for I/O submitted
via io_uring
- Increase buffer for afs volume status to avoid overflow
- Fix a missing zero-length check in unbuffered writes in the
netfs library. If generic_write_checks() returns zero make
netfs_unbuffered_write_iter() return right away
- Prevent a leak in i_dio_count caused by netfs_begin_read() operating
past i_size. It will return early and leave i_dio_count incremented
- Account for ipv4 addresses as well as ipv6 addresses when processing
incoming callbacks in afs
* tag 'vfs-6.8-rc6.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
fs/aio: Restrict kiocb_set_cancel_fn() to I/O submitted via libaio
afs: Increase buffer size in afs_update_volume_status()
afs: Fix ignored callbacks over ipv4
cachefiles: fix memory leak in cachefiles_add_cache()
netfs: Fix missing zero-length check in unbuffered write
netfs: Fix i_dio_count leak on DIO read past i_size
At btrfs_use_block_rsv() we read the size of a block reserve without
locking its spinlock, which makes KCSAN complain because the size of a
block reserve is always updated while holding its spinlock. The report
from KCSAN is the following:
[653.313148] BUG: KCSAN: data-race in btrfs_update_delayed_refs_rsv [btrfs] / btrfs_use_block_rsv [btrfs]
[653.314755] read to 0x000000017f5871b8 of 8 bytes by task 7519 on cpu 0:
[653.314779] btrfs_use_block_rsv+0xe4/0x2f8 [btrfs]
[653.315606] btrfs_alloc_tree_block+0xdc/0x998 [btrfs]
[653.316421] btrfs_force_cow_block+0x220/0xe38 [btrfs]
[653.317242] btrfs_cow_block+0x1ac/0x568 [btrfs]
[653.318060] btrfs_search_slot+0xda2/0x19b8 [btrfs]
[653.318879] btrfs_del_csums+0x1dc/0x798 [btrfs]
[653.319702] __btrfs_free_extent.isra.0+0xc24/0x2028 [btrfs]
[653.320538] __btrfs_run_delayed_refs+0xd3c/0x2390 [btrfs]
[653.321340] btrfs_run_delayed_refs+0xae/0x290 [btrfs]
[653.322140] flush_space+0x5e4/0x718 [btrfs]
[653.322958] btrfs_preempt_reclaim_metadata_space+0x102/0x2f8 [btrfs]
[653.323781] process_one_work+0x3b6/0x838
[653.323800] worker_thread+0x75e/0xb10
[653.323817] kthread+0x21a/0x230
[653.323836] __ret_from_fork+0x6c/0xb8
[653.323855] ret_from_fork+0xa/0x30
[653.323887] write to 0x000000017f5871b8 of 8 bytes by task 576 on cpu 3:
[653.323906] btrfs_update_delayed_refs_rsv+0x1a4/0x250 [btrfs]
[653.324699] btrfs_add_delayed_data_ref+0x468/0x6d8 [btrfs]
[653.325494] btrfs_free_extent+0x76/0x120 [btrfs]
[653.326280] __btrfs_mod_ref+0x6a8/0x6b8 [btrfs]
[653.327064] btrfs_dec_ref+0x50/0x70 [btrfs]
[653.327849] walk_up_proc+0x236/0xa50 [btrfs]
[653.328633] walk_up_tree+0x21c/0x448 [btrfs]
[653.329418] btrfs_drop_snapshot+0x802/0x1328 [btrfs]
[653.330205] btrfs_clean_one_deleted_snapshot+0x184/0x238 [btrfs]
[653.330995] cleaner_kthread+0x2b0/0x2f0 [btrfs]
[653.331781] kthread+0x21a/0x230
[653.331800] __ret_from_fork+0x6c/0xb8
[653.331818] ret_from_fork+0xa/0x30
So add a helper to get the size of a block reserve while holding the lock.
Reading the field while holding the lock instead of using the data_race()
annotation is used in order to prevent load tearing.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
