[syzbot] WARNING in btrfs_commit_transaction

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: b229b6ca5abb Merge tag 'perf-tools-fixes-for-v6.1-2022-10-..
git tree: upstream
console+strace: https://syzkaller.appspot.com/x/log.txt?x=12db9c7e880000
kernel config: https://syzkaller.appspot.com/x/.config?x=a66c6c673fb555e8
dashboard link: https://syzkaller.appspot.com/bug?extid=9c37714c07194d816417
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=17401632880000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=13176716880000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/ba5b49fa77de/disk-b229b6ca.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/7c061f2ae4dc/vmlinux-b229b6ca.xz
kernel image: https://storage.googleapis.com/syzbot-assets/bc45c1300e9b/bzImage-b229b6ca.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/62077524a72d/mount_0.gz

Bisection is inconclusive: the issue happens on the oldest tested release.

bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=14e432a6880000
final oops: https://syzkaller.appspot.com/x/report.txt?x=16e432a6880000
console output: https://syzkaller.appspot.com/x/log.txt?x=12e432a6880000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+9c3771...@syzkaller.appspotmail.com

BTRFS info (device loop0): clearing compat-ro feature flag for FREE_SPACE_TREE (0x1)
BTRFS info (device loop0): clearing compat-ro feature flag for FREE_SPACE_TREE_VALID (0x2)
BTRFS info (device loop0): checking UUID tree
BTRFS warning (device loop0): Skipping commit of aborted transaction.
------------[ cut here ]------------
BTRFS: Transaction aborted (error -12)
WARNING: CPU: 0 PID: 3608 at fs/btrfs/transaction.c:1958 cleanup_transaction fs/btrfs/transaction.c:1958 [inline]
WARNING: CPU: 0 PID: 3608 at fs/btrfs/transaction.c:1958 btrfs_commit_transaction.cold+0x356/0xae3 fs/btrfs/transaction.c:2531
Modules linked in:
CPU: 0 PID: 3608 Comm: syz-executor286 Not tainted 6.1.0-rc2-syzkaller-00105-gb229b6ca5abb #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/11/2022
RIP: 0010:cleanup_transaction fs/btrfs/transaction.c:1958 [inline]
RIP: 0010:btrfs_commit_transaction.cold+0x356/0xae3 fs/btrfs/transaction.c:2531
Code: fe ff ff e8 fa 28 27 f8 0f 0b e9 3f fe ff ff 31 db e9 d9 fe ff ff e8 e7 28 27 f8 44 89 ee 48 c7 c7 60 a5 37 8a e8 44 4a f4 ff <0f> 0b bb 01 00 00 00 e9 b9 fe ff ff e8 c7 28 27 f8 48 8b 95 00 ff
RSP: 0018:ffffc9000402fc70 EFLAGS: 00010286
RAX: 0000000000000000 RBX: ffff888077eb4000 RCX: 0000000000000000
RDX: ffff88807c599d40 RSI: ffffffff81621b98 RDI: fffff52000805f80
RBP: ffffc9000402fdf0 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000080000000 R11: 0000000046525442 R12: 0000000000000000
R13: 00000000fffffff4 R14: ffff8880704d60a8 R15: ffff888077eb4000
FS: 0000555556f2b300(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffe136c1ee0 CR3: 000000006fa8b000 CR4: 0000000000350ef0
Call Trace:
<TASK>
btrfs_sync_fs+0x169/0x810 fs/btrfs/super.c:1527
sync_fs_one_sb fs/sync.c:84 [inline]
sync_fs_one_sb+0x107/0x140 fs/sync.c:80
iterate_supers+0x13c/0x290 fs/super.c:723
ksys_sync+0xa8/0x150 fs/sync.c:104
__do_sys_sync+0xa/0x10 fs/sync.c:113
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7ff58bb49179
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffeb9ddd228 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007ff58bb49179
RDX: 0000000000000230 RSI: 000000000000c0c2 RDI: 00007ffeb9ddd230
RBP: 00007ffeb9ddd230 R08: 0000000000000001 R09: 00007ff58bbb0035
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003
R13: 0000000000000000 R14: 0000100000000000 R15: 0000000000000000
</TASK>


---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzk...@googlegroups.com.

syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
For information about bisection process see: https://goo.gl/tpsmEJ#bisection
syzbot can test patches for this issue, for details see:
https://goo.gl/tpsmEJ#testing-patches

[David Sterba]

-12 is ENOMEM, so another point for adding it to the list of exceptions
and not reporting the stacktrace. We have other warnings or assertions
to catch bad cleanup after errors.

[syzbot]

syzbot suspects this issue was fixed by commit:

commit 8bb808c6ad91ec3d332f072ce8f8aa4b16e307e0
Author: David Sterba <dst...@suse.com>
Date: Thu Nov 3 13:39:01 2022 +0000

btrfs: don't print stack trace when transaction is aborted due to ENOMEM

bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=14e020bd880000
start commit: b229b6ca5abb Merge tag 'perf-tools-fixes-for-v6.1-2022-10-..
git tree: upstream

kernel config: https://syzkaller.appspot.com/x/.config?x=a66c6c673fb555e8
dashboard link: https://syzkaller.appspot.com/bug?extid=9c37714c07194d816417

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=17401632880000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=13176716880000

If the result looks correct, please mark the issue as fixed by replying with:

#syz fix: btrfs: don't print stack trace when transaction is aborted due to ENOMEM

[Marco Elver]

#syz fix: btrfs: don't print stack trace when transaction is aborted
due to ENOMEM

> --
> You received this message because you are subscribed to the Google Groups "syzkaller-bugs" group.
> To unsubscribe from this group and stop receiving emails from it, send an email to syzkaller-bug...@googlegroups.com.
> To view this discussion on the web visit https://groups.google.com/d/msgid/syzkaller-bugs/000000000000d921ab05ee8e4f48%40google.com.

[Dmitry Vyukov]

On Tue, 29 Nov 2022 at 23:13, 'Marco Elver' via syzkaller-bugs
<syzkall...@googlegroups.com> wrote:
>
> #syz fix: btrfs: don't print stack trace when transaction is aborted
> due to ENOMEM

fix truncated line

> To view this discussion on the web visit https://groups.google.com/d/msgid/syzkaller-bugs/CANpmjNMS3BGeWix%3D-OBKCK_iorQiGVay58f5U4fJiebF6msPSQ%40mail.gmail.com.