[v6.6] WARNING in reiserfs_setattr

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 0a805b6ea8cd Linux 6.6.116
git tree: linux-6.6.y
console output: https://syzkaller.appspot.com/x/log.txt?x=11125332580000
kernel config: https://syzkaller.appspot.com/x/.config?x=12606d4b8832c7e4
dashboard link: https://syzkaller.appspot.com/bug?extid=5de37bed882cffd1dc6d
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/13874446b4b2/disk-0a805b6e.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/69a5e59e1ade/vmlinux-0a805b6e.xz
kernel image: https://storage.googleapis.com/syzbot-assets/322c0711f976/bzImage-0a805b6e.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+5de37b...@syzkaller.appspotmail.com

loop3: detected capacity change from 0 to 64
------------[ cut here ]------------
DEBUG_LOCKS_WARN_ON(lock->magic != lock)
WARNING: CPU: 0 PID: 28592 at kernel/locking/mutex.c:582 __mutex_lock_common kernel/locking/mutex.c:582 [inline]
WARNING: CPU: 0 PID: 28592 at kernel/locking/mutex.c:582 __mutex_lock+0xb8c/0xcc0 kernel/locking/mutex.c:747
Modules linked in:
CPU: 0 PID: 28592 Comm: syz.3.10210 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:__mutex_lock_common kernel/locking/mutex.c:582 [inline]
RIP: 0010:__mutex_lock+0xb8c/0xcc0 kernel/locking/mutex.c:747
Code: 04 08 84 c0 0f 85 20 01 00 00 83 3d dd 49 d3 03 00 0f 85 81 f5 ff ff 48 c7 c7 80 a7 aa 8a 48 c7 c6 20 a8 aa 8a e8 94 94 d8 f6 <0f> 0b e9 67 f5 ff ff 0f 0b e9 47 f9 ff ff 0f 0b e9 ff f5 ff ff 48
RSP: 0018:ffffc900101a7920 EFLAGS: 00010246
RAX: 8f4d5f1d12ecc700 RBX: ffff88805833f0a8 RCX: 0000000000080000
RDX: ffffc9000df0c000 RSI: 00000000000121d7 RDI: 00000000000121d8
RBP: ffffc900101a7a80 R08: ffff8880b8e28c13 R09: 1ffff110171c5182
R10: dffffc0000000000 R11: ffffed10171c5183 R12: 0000000000000000
R13: 1ffff92002034f34 R14: dffffc0000000000 R15: 0000000000000000
FS: 00007f2a27c0d6c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c242543 CR3: 000000002498b000 CR4: 00000000003506f0
Call Trace:
<TASK>
reiserfs_write_lock+0x79/0xd0 fs/reiserfs/lock.c:27
reiserfs_setattr+0x3f4/0x11a0 fs/reiserfs/inode.c:3281
notify_change+0xb0d/0xe10 fs/attr.c:499
chown_common+0x3f9/0x5a0 fs/open.c:783
do_fchownat+0x168/0x270 fs/open.c:814
__do_sys_lchown fs/open.c:839 [inline]
__se_sys_lchown fs/open.c:837 [inline]
__x64_sys_lchown+0x85/0x90 fs/open.c:837
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f2a26d8f6c9
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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f2a27c0d038 EFLAGS: 00000246 ORIG_RAX: 000000000000005e
RAX: ffffffffffffffda RBX: 00007f2a26fe5fa0 RCX: 00007f2a26d8f6c9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000200000000000
RBP: 00007f2a26e11f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f2a26fe6038 R14: 00007f2a26fe5fa0 R15: 00007ffdb7188828
</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.

If the report is already addressed, let syzbot know by replying with:
#syz fix: exact-commit-title

If you want to overwrite report's subsystems, reply with:
#syz set subsystems: new-subsystem
(See the list of subsystem names on the web dashboard)

If the report is a duplicate of another one, reply with:
#syz dup: exact-subject-of-another-report

If you want to undo deduplication, reply with:
#syz undup