WARNING in udf_expand_dir_adinicb (2)

Status: upstream: reported syz repro on 2025/05/27 03:55
Subsystems: udf
Labels: prio:low
[Documentation on labels]
Reported-by: syzbot+545e45805722d117958f@syzkaller.appspotmail.com
First crash: 459d, last: 28d
Cause bisection: failed (error log, bisect log)
  
Fix bisection: the issue occurs on the latest tested release (bisect log)
  
✨ AI Jobs (3)
ID Workflow Result Correct Bug Created Started Finished Revision
ebc147dc patching 💥 WARNING in udf_expand_dir_adinicb (2) 2026/08/07 17:00 2026/08/08 01:48 2026/08/08 02:16 e4ef95d6
8df708a9 patching 💥 WARNING in udf_expand_dir_adinicb (2) 2026/07/15 13:25 2026/07/15 13:26 2026/07/15 13:51 66e29b17
d5f54fc8 assessment-security DenialOfService: ❌ Exploitable: ❌ FilesystemTrigger: ✅ NetworkTrigger: ❌ PeripheralTrigger: ✅ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ❌ VMGuestTrigger: ❌ VMHostTrigger: ❌ WARNING in udf_expand_dir_adinicb (2) 2026/05/20 00:17 2026/05/20 00:17 2026/05/20 01:02 1d9407ad
Discussions (3)
Title Replies (including bot) Last reply
[syzbot] Monthly udf report (Jul 2025) 0 (1) 2025/07/26 20:43
[syzbot] Monthly udf report (Jun 2025) 0 (1) 2025/06/24 13:54
[syzbot] [udf?] WARNING in udf_expand_dir_adinicb (2) 0 (2) 2025/05/27 07:11
Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream WARNING in udf_expand_dir_adinicb udf -1 syz, C done 2 1296d 1292d 22/29 fixed on 2023/06/08 14:41
Last patch testing requests (8)
Created Duration User Patch Repo Result
2026/08/23 08:22 24m retest repro upstream no crash job log log
2026/05/26 01:02 1h41m retest repro upstream log
2026/03/16 23:59 22m retest repro upstream report log
2026/01/05 22:14 25m retest repro upstream report log
2025/10/27 21:37 23m retest repro upstream report log
2025/08/20 02:48 22m retest repro upstream no crash log
2025/06/10 20:41 23m retest repro upstream report log
2025/06/10 20:41 23m retest repro upstream report log
Fix bisection attempts (2)
Created Duration User Patch Repo Result
2025/08/18 08:59 4h33m bisect fix upstream OK (0) job log
2025/07/11 22:35 3h22m bisect fix upstream OK (0) job log log

Sample crash report:
------------[ cut here ]------------
ret
WARNING: fs/udf/namei.c:214 at udf_expand_dir_adinicb+0xc87/0xed0 fs/udf/namei.c:214, CPU#0: syz.4.2461/13602
Modules linked in:
CPU: 0 UID: 0 PID: 13602 Comm: syz.4.2461 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
RIP: 0010:udf_expand_dir_adinicb+0xc87/0xed0 fs/udf/namei.c:214
Code: a7 d3 fe 48 8b 4c 24 38 48 8b 54 24 28 e9 58 fa ff ff e8 6c 18 64 fe 4c 89 ff e8 54 83 fd fe e9 1b f8 ff ff e8 5a 18 64 fe 90 <0f> 0b 90 e9 e7 fd ff ff bb 8b ff ff ff e9 f4 f5 ff ff bb f4 ff ff
RSP: 0018:ffffc90007b57420 EFLAGS: 00010283
RAX: 000000000000ce4c RBX: 00000000ffffff8b RCX: ffffc90007bb1000
RDX: 0000000000080000 RSI: ffffffff83a626c6 RDI: ffff88807f59dd00
RBP: ffffc90007b57698 R08: 0000000000000005 R09: 0000000000000000
R10: 00000000ffffff8b R11: 0000000000000000 R12: 00000000ffffff8b
R13: 0000000000000000 R14: 0000000000000000 R15: ffff888055445b60
FS:  00007f499f5006c0(0000) GS:ffff888123dde000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4b32a0a000 CR3: 000000005cd71000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 udf_fiiter_add_entry+0xcb1/0x10c0 fs/udf/namei.c:262
 udf_rename+0xaf1/0xdc0 fs/udf/namei.c:843
 vfs_rename+0xc9f/0x2000 fs/namei.c:6074
 filename_renameat2+0x754/0xa60 fs/namei.c:6192
 __do_sys_rename fs/namei.c:6236 [inline]
 __se_sys_rename fs/namei.c:6232 [inline]
 __x64_sys_rename+0x81/0xb0 fs/namei.c:6232
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f499e59de99
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f499f500028 EFLAGS: 00000246 ORIG_RAX: 0000000000000052
RAX: ffffffffffffffda RBX: 00007f499e825fa0 RCX: 00007f499e59de99
RDX: 0000000000000000 RSI: 0000200000000f40 RDI: 00002000000003c0
RBP: 00007f499e633eaf R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f499e826038 R14: 00007f499e825fa0 R15: 00007ffc6c405d58
 </TASK>

Crashes (9):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/07/27 15:26 upstream f5098b6bae76 4cb2b096 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in udf_expand_dir_adinicb
2026/07/25 15:05 upstream 0ce37745d4bf 492bab15 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in udf_expand_dir_adinicb
2026/07/20 14:36 upstream 1590cf032971 de6a700d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in udf_expand_dir_adinicb
2026/07/17 07:45 upstream fce2dfa773ce 7f27c57a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in udf_expand_dir_adinicb
2026/07/14 19:43 upstream 3b029c035b34 2130f682 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in udf_expand_dir_adinicb
2026/07/13 02:32 upstream a13c140cc289 d78ea535 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in udf_expand_dir_adinicb
2025/05/27 08:55 upstream 0ff41df1cb26 874a1386 .config console log report syz / log [disk image] [vmlinux] [kernel image] [mounted in repro] ci-upstream-kasan-badwrites-root WARNING in udf_expand_dir_adinicb
2025/05/27 07:10 upstream 0ff41df1cb26 874a1386 .config console log report syz / log [disk image] [vmlinux] [kernel image] [mounted in repro] ci-upstream-kasan-badwrites-root WARNING in udf_expand_dir_adinicb
2025/05/23 03:48 upstream 94305e83eccb fa44301a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in udf_expand_dir_adinicb
* Struck through repros no longer work on HEAD.