[v6.6] WARNING in udf_new_block

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: c596736dadab Linux 6.6.120
git tree: linux-6.6.y
console output: https://syzkaller.appspot.com/x/log.txt?x=17d9059a580000
kernel config: https://syzkaller.appspot.com/x/.config?x=691a6769a86ac817
dashboard link: https://syzkaller.appspot.com/bug?extid=a0b44fc3e53c92726eb9
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/855c94eb3eef/disk-c596736d.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/b7510b30b774/vmlinux-c596736d.xz
kernel image: https://storage.googleapis.com/syzbot-assets/3ce7fe4f6991/bzImage-c596736d.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+a0b44f...@syzkaller.appspotmail.com

------------[ cut here ]------------
WARNING: CPU: 1 PID: 6113 at fs/udf/udfdecl.h:123 udf_updated_lvid fs/udf/udfdecl.h:121 [inline]
WARNING: CPU: 1 PID: 6113 at fs/udf/udfdecl.h:123 udf_add_free_space fs/udf/balloc.c:133 [inline]
WARNING: CPU: 1 PID: 6113 at fs/udf/udfdecl.h:123 udf_table_new_block fs/udf/balloc.c:665 [inline]
WARNING: CPU: 1 PID: 6113 at fs/udf/udfdecl.h:123 udf_new_block+0x1830/0x1a70 fs/udf/balloc.c:742
Modules linked in:
CPU: 1 PID: 6113 Comm: syz.0.38 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:udf_updated_lvid fs/udf/udfdecl.h:121 [inline]
RIP: 0010:udf_add_free_space fs/udf/balloc.c:133 [inline]
RIP: 0010:udf_table_new_block fs/udf/balloc.c:665 [inline]
RIP: 0010:udf_new_block+0x1830/0x1a70 fs/udf/balloc.c:742
Code: fe 48 8b bc 24 80 00 00 00 e8 4c 7f 7b 07 45 31 ed 49 bf 00 00 00 00 00 fc ff df 48 8b 5c 24 50 e9 82 fd ff ff e8 50 92 90 fe <0f> 0b e9 a6 fc ff ff e8 44 92 90 fe 0f 0b e9 37 ff ff ff 44 89 f1
RSP: 0018:ffffc900055af600 EFLAGS: 00010283
RAX: ffffffff82f518b0 RBX: 0000000055555555 RCX: 0000000000080000
RDX: ffffc9000ecd0000 RSI: 0000000000002549 RDI: 000000000000254a
RBP: ffffc900055af850 R08: ffffffff8e4a39ef R09: 1ffffffff1c9473d
R10: dffffc0000000000 R11: fffffbfff1c9473e R12: ffff88802e894000
R13: 0000000000000038 R14: ffff88802489c01f R15: dffffc0000000000
FS: 00007f63aac4a6c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f63aac49f98 CR3: 000000005c25d000 CR4: 00000000003506e0
Call Trace:
<TASK>
udf_new_inode+0x39a/0xd10 fs/udf/ialloc.c:67
udf_create+0x23/0xe0 fs/udf/namei.c:380
lookup_open fs/namei.c:3496 [inline]
open_last_lookups fs/namei.c:3564 [inline]
path_openat+0x1277/0x3190 fs/namei.c:3794
do_filp_open+0x1c5/0x3d0 fs/namei.c:3824
do_sys_openat2+0x12c/0x1c0 fs/open.c:1421
do_sys_open fs/open.c:1436 [inline]
__do_sys_openat fs/open.c:1452 [inline]
__se_sys_openat fs/open.c:1447 [inline]
__x64_sys_openat+0x139/0x160 fs/open.c:1447
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f63a9d8f749
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:00007f63aac4a038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f63a9fe6270 RCX: 00007f63a9d8f749
RDX: 000000000000275a RSI: 0000200000000840 RDI: ffffffffffffff9c
RBP: 00007f63a9e13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f63a9fe6308 R14: 00007f63a9fe6270 R15: 00007ffc81b730f8
</TASK>


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