syzbot


WARNING in __udf_add_aext

Status: upstream: reported C repro on 2025/07/30 23:41
Bug presence: origin:upstream
[Documentation on labels]
Reported-by: syzbot+7e3876c1d0bf0b7e3895@syzkaller.appspotmail.com
First crash: 147d, last: 14d
Bug presence (1)
Date Name Commit Repro Result
2025/08/01 upstream (ToT) f2d282e1dfb3 C [report] WARNING in __udf_add_aext
Similar bugs (7)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 WARNING in __udf_add_aext origin:upstream -1 C done 134 24d 858d 0/3 upstream: reported C repro on 2023/08/20 05:08
linux-4.14 WARNING in __udf_add_aext udf -1 C 3 1028d 1405d 0/1 upstream: reported C repro on 2022/02/18 06:47
upstream WARNING in __udf_add_aext (3) udf -1 C error 1491 2h15m 625d 0/29 upstream: reported C repro on 2024/04/08 08:26
linux-4.19 WARNING in __udf_add_aext udf -1 C error 20 1039d 1440d 0/1 upstream: reported C repro on 2022/01/14 21:09
upstream WARNING in __udf_add_aext udf -1 C error 170 934d 1171d 22/29 fixed on 2023/06/08 14:41
upstream WARNING in __udf_add_aext (2) udf -1 syz error done 6 744d 925d 25/29 fixed on 2024/01/30 15:47
linux-6.1 WARNING in __udf_add_aext origin:lts-only -1 C done 136 1d07h 808d 0/3 upstream: reported C repro on 2023/10/08 20:16
Fix bisection attempts (2)
Created Duration User Patch Repo Result
2025/11/06 06:55 1h15m bisect fix linux-6.6.y OK (0) job log log
2025/09/05 07:03 1h56m bisect fix linux-6.6.y OK (0) job log log

Sample crash report:
syz.0.17[5919]: memfd_create() called without MFD_EXEC or MFD_NOEXEC_SEAL set
loop0: detected capacity change from 0 to 2048
UDF-fs: error (device loop0): udf_process_sequence: Primary Volume Descriptor not found!
UDF-fs: INFO Mounting volume 'LinuxUDF', timestamp 2022/11/22 14:59 (1000)
------------[ cut here ]------------
WARNING: CPU: 0 PID: 5919 at fs/udf/inode.c:2081 __udf_add_aext+0x51e/0x6d0 fs/udf/inode.c:2080
Modules linked in:
CPU: 0 PID: 5919 Comm: syz.0.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:__udf_add_aext+0x51e/0x6d0 fs/udf/inode.c:2080
Code: 08 4c 89 f7 e8 43 da e6 fe 49 8b 3e 4c 89 e6 e8 68 8e 05 ff 31 c0 48 83 c4 28 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 32 6c 8f fe <0f> 0b e9 1b fc ff ff e8 26 6c 8f fe 0f 0b e9 6f fd ff ff e8 1a 6c
RSP: 0018:ffffc900031c7868 EFLAGS: 00010293
RAX: ffffffff82f6248e RBX: dffffc0000000000 RCX: ffff8880261a9e00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000000001d0
RBP: 1ffff92000638f79 R08: ffff8880261a9e00 R09: 0000000000000002
R10: 0000000000000001 R11: 0000000000000000 R12: 00000000000001d0
R13: 0000000000000000 R14: ffffc900031c7bc0 R15: ffffc900031c7bc8
FS:  0000555560db9500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b33963fff CR3: 0000000020e30000 CR4: 00000000003506f0
Call Trace:
 <TASK>
 udf_setup_indirect_aext+0x5d7/0x7a0 fs/udf/inode.c:2043
 udf_add_aext fs/udf/inode.c:2133 [inline]
 udf_do_extend_file+0x870/0x1170 fs/udf/inode.c:588
 udf_extend_file fs/udf/inode.c:709 [inline]
 udf_setsize+0xbea/0x10a0 fs/udf/inode.c:1299
 udf_setattr+0x3a1/0x5a0 fs/udf/file.c:236
 notify_change+0xb0d/0xe10 fs/attr.c:499
 do_truncate+0x19b/0x220 fs/open.c:66
 vfs_truncate+0x266/0x300 fs/open.c:112
 do_sys_truncate+0xe0/0x1a0 fs/open.c:135
 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: 0033:0x7f5f5c18f749
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:00007ffe71023dd8 EFLAGS: 00000246 ORIG_RAX: 000000000000004c
RAX: ffffffffffffffda RBX: 00007f5f5c3e5fa0 RCX: 00007f5f5c18f749
RDX: 0000000000000000 RSI: 000002400000f000 RDI: 0000200000000c00
RBP: 00007f5f5c213f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f5f5c3e5fa0 R14: 00007f5f5c3e5fa0 R15: 0000000000000002
 </TASK>

Crashes (10):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/12/08 16:40 linux-6.6.y 5fa4793a2d2d d6526ea3 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-6-6-kasan WARNING in __udf_add_aext
2025/07/31 02:15 linux-6.6.y dbcb8d8e4163 f8f2b4da .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-6-6-kasan WARNING in __udf_add_aext
2025/12/11 01:46 linux-6.6.y 5fa4793a2d2d d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in __udf_add_aext
2025/11/30 03:17 linux-6.6.y 1e89a1be4fe9 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in __udf_add_aext
2025/09/26 16:29 linux-6.6.y 147338df3487 0abd0691 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in __udf_add_aext
2025/09/26 16:23 linux-6.6.y 147338df3487 0abd0691 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in __udf_add_aext
2025/09/25 20:08 linux-6.6.y 147338df3487 0abd0691 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in __udf_add_aext
2025/09/25 20:07 linux-6.6.y 147338df3487 0abd0691 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in __udf_add_aext
2025/07/30 23:43 linux-6.6.y dbcb8d8e4163 f8f2b4da .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in __udf_add_aext
2025/07/30 23:41 linux-6.6.y dbcb8d8e4163 f8f2b4da .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in __udf_add_aext
* Struck through repros no longer work on HEAD.