syzbot
WARNING in ext4_journal_check_start
Status:
upstream: reported C repro on 2025/12/08 18:38
Bug presence:
origin:lts-only
[Documentation on labels]
Reported-by: syzbot+1b8918e16f1cb8a441e1@syzkaller.appspotmail.com
First crash: 301d, last: 3h10m
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Fix bisection attempts (1)
| Created |
Duration |
User |
Patch |
Repo |
Result |
| 2026/01/01 13:47 |
1h40m
|
fix candidate
|
|
upstream |
OK
(0)
job log
|
Sample crash report:
fscrypt: AES-256-CTS-CBC using implementation "cts-cbc-aes-aesni"
------------[ cut here ]------------
WARNING: CPU: 0 PID: 5935 at fs/ext4/ext4_jbd2.c:73 ext4_journal_check_start+0x1eb/0x250 fs/ext4/ext4_jbd2.c:73
Modules linked in:
CPU: 0 PID: 5935 Comm: syz.0.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:ext4_journal_check_start+0x1eb/0x250 fs/ext4/ext4_jbd2.c:73
Code: 48 83 c4 08 41 bf e2 ff ff ff 44 89 f8 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 c2 b8 59 ff 41 bf fb ff ff ff eb e5 e8 b5 b8 59 ff <0f> 0b eb d6 e8 ac b8 59 ff 0f 0b 43 80 7c 25 00 00 0f 85 0b ff ff
RSP: 0018:ffffc900047cf658 EFLAGS: 00010293
RAX: ffffffff822dd7fb RBX: ffff88814233e000 RCX: ffff888024fc8000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: 0000000000000bfe R08: ffff888141f38417 R09: 1ffff110283e7082
R10: dffffc0000000000 R11: ffffed10283e7083 R12: dffffc0000000000
R13: 1ffff11028467cc6 R14: ffff88814233e630 R15: 0000000000000001
FS: 00007f8e9514b6c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f9479f4a6b0 CR3: 000000007b991000 CR4: 00000000003506f0
Call Trace:
<TASK>
__ext4_journal_start_sb+0x147/0x560 fs/ext4/ext4_jbd2.c:105
__ext4_new_inode+0x13c7/0x3aa0 fs/ext4/ialloc.c:1091
ext4_mkdir+0x40b/0xc90 fs/ext4/namei.c:3068
vfs_mkdir+0x2a5/0x470 fs/namei.c:4168
cachefiles_get_directory+0x231/0xa70 fs/cachefiles/namei.c:133
cachefiles_add_cache+0xa88/0xd50 fs/cachefiles/cache.c:127
cachefiles_daemon_write+0x5f9/0x6b0 fs/cachefiles/daemon.c:344
vfs_write+0x299/0x9a0 fs/read_write.c:582
ksys_write+0x151/0x260 fs/read_write.c:637
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: 0033:0x7f8e9419e159
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:00007f8e9514b028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f8e94425fa0 RCX: 00007f8e9419e159
RDX: 0000000000000004 RSI: 0000200000000700 RDI: 0000000000000004
RBP: 00007f8e9423506b R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8e94426038 R14: 00007f8e94425fa0 R15: 00007ffd86704068
</TASK>
* Struck through repros no longer work on HEAD.