diff options
| author | Qu Wenruo <wqu@suse.com> | 2023-11-11 07:14:57 +1030 |
|---|---|---|
| committer | David Sterba <dsterba@suse.com> | 2023-11-15 17:08:14 +0100 |
| commit | 8049ba5d0a28c7208285e94e71a8df5e41a2e889 (patch) | |
| tree | 9dc28530c91cd0f07aecdb119f328eac7e4ff54e /fs/btrfs/transaction.c | |
| parent | 1645c283a87c61f84b2bffd81f50724df959b11a (diff) | |
btrfs: do not abort transaction if there is already an existing qgroup
[BUG]
Syzbot reported a regression that after commit 6ed05643ddb1 ("btrfs:
create qgroup earlier in snapshot creation") we can trigger transaction
abort during snapshot creation:
BTRFS: Transaction aborted (error -17)
WARNING: CPU: 0 PID: 5057 at fs/btrfs/transaction.c:1778 create_pending_snapshot+0x25f4/0x2b70 fs/btrfs/transaction.c:1778
Modules linked in:
CPU: 0 PID: 5057 Comm: syz-executor225 Not tainted 6.6.0-syzkaller-15365-g305230142ae0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/09/2023
RIP: 0010:create_pending_snapshot+0x25f4/0x2b70 fs/btrfs/transaction.c:1778
Call Trace:
<TASK>
create_pending_snapshots+0x195/0x1d0 fs/btrfs/transaction.c:1967
btrfs_commit_transaction+0xf1c/0x3730 fs/btrfs/transaction.c:2440
create_snapshot+0x4a5/0x7e0 fs/btrfs/ioctl.c:845
btrfs_mksubvol+0x5d0/0x750 fs/btrfs/ioctl.c:995
btrfs_mksnapshot+0xb5/0xf0 fs/btrfs/ioctl.c:1041
__btrfs_ioctl_snap_create+0x344/0x460 fs/btrfs/ioctl.c:1294
btrfs_ioctl_snap_create+0x13c/0x190 fs/btrfs/ioctl.c:1321
btrfs_ioctl+0xbbf/0xd40
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:871 [inline]
__se_sys_ioctl+0xf8/0x170 fs/ioctl.c:857
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x63/0x6b
RIP: 0033:0x7f2f791127b9
</TASK>
[CAUSE]
The error number is -EEXIST, which can happen for qgroup if there is
already an existing qgroup and then we're trying to create a snapshot
for it.
[FIX]
In that case, we can continue creating the snapshot, although it may
lead to qgroup inconsistency, it's not so critical to abort the current
transaction.
So in this case, we can just ignore the non-critical errors, mostly -EEXIST
(there is already a qgroup).
Reported-by: syzbot+4d81015bc10889fd12ea@syzkaller.appspotmail.com
Fixes: 6ed05643ddb1 ("btrfs: create qgroup earlier in snapshot creation")
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Diffstat (limited to 'fs/btrfs/transaction.c')
| -rw-r--r-- | fs/btrfs/transaction.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c index 9694a3ca1739..7af9665bebae 100644 --- a/fs/btrfs/transaction.c +++ b/fs/btrfs/transaction.c @@ -1774,7 +1774,7 @@ static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans, btrfs_release_path(path); ret = btrfs_create_qgroup(trans, objectid); - if (ret) { + if (ret && ret != -EEXIST) { btrfs_abort_transaction(trans, ret); goto fail; } |