[v6.6] WARNING in udf_unlink

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 3a8ababb8b6a Linux 6.6.101
git tree: linux-6.6.y
console output: https://syzkaller.appspot.com/x/log.txt?x=13a3f042580000
kernel config: https://syzkaller.appspot.com/x/.config?x=a2bd95b6de4839b7
dashboard link: https://syzkaller.appspot.com/bug?extid=e933fbe57125a64776cd
compiler: Debian clang version 20.1.7 (++20250616065708+6146a88f6049-1~exp1~20250616065826.132), Debian LLD 20.1.7
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1353d1a2580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=15c209a2580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/f06c672f5fa8/disk-3a8ababb.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/9af9b7afcdc5/vmlinux-3a8ababb.xz
kernel image: https://storage.googleapis.com/syzbot-assets/351a55aafa77/bzImage-3a8ababb.xz
mounted in repro #1: https://storage.googleapis.com/syzbot-assets/1ede947b301e/mount_0.gz
fsck result: failed (log: https://syzkaller.appspot.com/x/fsck.log?x=14bed434580000)
mounted in repro #2: https://storage.googleapis.com/syzbot-assets/3f3c34fe8ea6/mount_1.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e933fb...@syzkaller.appspotmail.com

------------[ cut here ]------------
WARNING: CPU: 1 PID: 5901 at fs/udf/udfdecl.h:123 udf_updated_lvid fs/udf/udfdecl.h:121 [inline]
WARNING: CPU: 1 PID: 5901 at fs/udf/udfdecl.h:123 udf_add_fid_counter fs/udf/namei.c:346 [inline]
WARNING: CPU: 1 PID: 5901 at fs/udf/udfdecl.h:123 udf_unlink+0x5a1/0x6d0 fs/udf/namei.c:565
Modules linked in:
CPU: 1 PID: 5901 Comm: syz-executor Not tainted 6.6.101-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:udf_updated_lvid fs/udf/udfdecl.h:121 [inline]
RIP: 0010:udf_add_fid_counter fs/udf/namei.c:346 [inline]
RIP: 0010:udf_unlink+0x5a1/0x6d0 fs/udf/namei.c:565
Code: 00 65 48 8b 04 25 28 00 00 00 48 3b 84 24 40 01 00 00 75 1d 89 d8 48 8d 65 d8 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 cf cf 8f fe <0f> 0b e9 a3 fe ff ff e8 c3 51 77 07 44 89 f1 80 e1 07 80 c1 03 38
RSP: 0018:ffffc900046ffbe0 EFLAGS: 00010293
RAX: ffffffff82f5c5c1 RBX: 00000000bc4d22a9 RCX: ffff88802a0d3c00
RDX: 0000000000000000 RSI: 00000000bc4d22a9 RDI: 0000000000000000
RBP: ffffc900046ffd80 R08: ffffffff8e4a84ef R09: 1ffffffff1c9509d
R10: dffffc0000000000 R11: fffffbfff1c9509e R12: ffff88802d08e630
R13: ffff88805dd0701f R14: 1ffff11005a11cc6 R15: dffffc0000000000
FS: 000055555d8e8500(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055555d913648 CR3: 0000000023ba7000 CR4: 00000000003506e0
Call Trace:
<TASK>
vfs_unlink+0x389/0x600 fs/namei.c:4325
do_unlinkat+0x328/0x570 fs/namei.c:4391
__do_sys_unlink fs/namei.c:4439 [inline]
__se_sys_unlink fs/namei.c:4437 [inline]
__x64_sys_unlink+0x49/0x50 fs/namei.c:4437
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: 0033:0x7f2ce758e197
Code: 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 57 00 00 00 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:00007ffc63a4d0d8 EFLAGS: 00000206 ORIG_RAX: 0000000000000057
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f2ce758e197
RDX: 00007ffc63a4d100 RSI: 00007ffc63a4d190 RDI: 00007ffc63a4d190
RBP: 00007ffc63a4d190 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000100 R11: 0000000000000206 R12: 00007ffc63a4e280
R13: 00007f2ce7611c05 R14: 000000000001490f R15: 00007ffc63a50440
</TASK>


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