[v6.1] kernel BUG in flush_commit_list

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: dcbcab9d7079 Linux 6.1.174
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=1634ed6a580000
kernel config: https://syzkaller.appspot.com/x/.config?x=b1adc0bfde2d8a4a
dashboard link: https://syzkaller.appspot.com/bug?extid=c81ade0ddf881df1bccc
compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8
userspace arch: arm64

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/afbb3144d02c/disk-dcbcab9d.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/645249aeb1d4/vmlinux-dcbcab9d.xz
kernel image: https://storage.googleapis.com/syzbot-assets/6dba7bfbb673/Image-dcbcab9d.gz.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+c81ade...@syzkaller.appspotmail.com

------------[ cut here ]------------
kernel BUG at fs/reiserfs/journal.c:1108!
Internal error: Oops - BUG: 00000000f2000800 [#1] PREEMPT SMP
Modules linked in:
CPU: 0 PID: 4554 Comm: syz-executor Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
pstate: 82400005 (Nzcv daif +PAN -UAO +TCO -DIT -SSBS BTYPE=--)
pc : flush_commit_list+0x1844/0x1870 fs/reiserfs/journal.c:1108
lr : flush_commit_list+0x1844/0x1870 fs/reiserfs/journal.c:1108
sp : ffff8000208d7360
x29: ffff8000208d7400 x28: dfff800000000000 x27: ffff0000f5d12400
x26: ffff0000d1dda678 x25: 1fffe0001a3bb403 x24: 00000000ffffffff
x23: ffff0000f5b57658 x22: ffff0000d1dda000 x21: ffff0000f5d124d0
x20: 0000000000000013 x19: 1fffe0001eba249a x18: ffff800011b9bf60
x17: 1fffe00033ea637e x16: ffff8000082d122c x15: ffff80001521d000
x14: 0000000000000001 x13: 1fffe0001eba2483 x12: 0000000000ff0100
x11: ff00800008cf4018 x10: 0000000000000000 x9 : ffff800008cf4018
x8 : ffff0000d49ad340 x7 : ffff800008d01e14 x6 : 0000000000000000
x5 : 0000000000000000 x4 : 0000000000000001 x3 : ffff800008cf3548
x2 : 0000000000000000 x1 : 0000000000000002 x0 : 0000000000000000
Call trace:
flush_commit_list+0x1844/0x1870 fs/reiserfs/journal.c:1108
flush_older_commits fs/reiserfs/journal.c:919 [inline]
flush_commit_list+0x368/0x1870 fs/reiserfs/journal.c:997
do_journal_end+0x3060/0x3bac fs/reiserfs/journal.c:4376
journal_end_sync+0x164/0x1d0 fs/reiserfs/journal.c:3539
reiserfs_sync_fs+0xe0/0x170 fs/reiserfs/super.c:78
sync_filesystem+0x1a0/0x218 fs/sync.c:66
generic_shutdown_super+0x70/0x324 fs/super.c:474
kill_block_super+0x70/0xdc fs/super.c:1470
reiserfs_kill_sb+0x124/0x13c fs/reiserfs/super.c:570
deactivate_locked_super+0xac/0x120 fs/super.c:332
deactivate_super+0xe4/0x104 fs/super.c:363
cleanup_mnt+0x390/0x418 fs/namespace.c:1191
__cleanup_mnt+0x20/0x30 fs/namespace.c:1198
task_work_run+0x1ec/0x278 kernel/task_work.c:203
resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
do_notify_resume+0x1fa0/0x2aa4 arch/arm64/kernel/signal.c:1151
prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:137 [inline]
exit_to_user_mode arch/arm64/kernel/entry-common.c:142 [inline]
el0_svc+0x98/0x128 arch/arm64/kernel/entry-common.c:638
el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585
Code: aa1403e0 97efce18 17ffffc1 97deddc8 (d4210000)
---[ end trace 0000000000000000 ]---


---
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[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit: dcbcab9d7079 Linux 6.1.174
git tree: linux-6.1.y

console output: https://syzkaller.appspot.com/x/log.txt?x=15ffd6d2580000

kernel config: https://syzkaller.appspot.com/x/.config?x=b1adc0bfde2d8a4a
dashboard link: https://syzkaller.appspot.com/bug?extid=c81ade0ddf881df1bccc
compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8
userspace arch: arm64

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1089db06580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=11ab8d36580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/afbb3144d02c/disk-dcbcab9d.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/645249aeb1d4/vmlinux-dcbcab9d.xz
kernel image: https://storage.googleapis.com/syzbot-assets/6dba7bfbb673/Image-dcbcab9d.gz.xz

mounted in repro: https://storage.googleapis.com/syzbot-assets/5327689ba37d/mount_0.gz
fsck result: failed (log: https://syzkaller.appspot.com/x/fsck.log?x=12f70a2e580000)

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+c81ade...@syzkaller.appspotmail.com

------------[ cut here ]------------
kernel BUG at fs/reiserfs/journal.c:1108!
Internal error: Oops - BUG: 00000000f2000800 [#1] PREEMPT SMP
Modules linked in:

CPU: 1 PID: 4434 Comm: syz-executor Not tainted syzkaller #0

Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
pstate: 82400005 (Nzcv daif +PAN -UAO +TCO -DIT -SSBS BTYPE=--)
pc : flush_commit_list+0x1844/0x1870 fs/reiserfs/journal.c:1108
lr : flush_commit_list+0x1844/0x1870 fs/reiserfs/journal.c:1108

sp : ffff800021297360
x29: ffff800021297400 x28: dfff800000000000 x27: ffff0000d101f400
x26: ffff0000ceb00678 x25: 1fffe00019d60003 x24: 00000000ffffffff
x23: ffff0000e0692d98 x22: ffff0000ceb00000 x21: ffff0000d101f4d0
x20: 0000000000000013 x19: 1fffe0001a203e9a x18: ffff800011b9bf60
x17: 1fffe00033eaa57e x16: ffff8000082d122c x15: 0000000040000000
x14: 0000000000000001 x13: 1fffe0001a203e83 x12: 0000000000ff0100

x11: ff00800008cf4018 x10: 0000000000000000 x9 : ffff800008cf4018

x8 : ffff0000ccd03780 x7 : ffff800008d01e14 x6 : 0000000000000000

If you want syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
If you attach or paste a git patch, syzbot will apply it before testing.