syzbot


kernel BUG in submit_bh_wbc

Status: upstream: reported C repro on 2023/06/15 00:20
Bug presence: origin:lts
Labels: missing-backport
[Documentation on labels]
Reported-by: syzbot+807c663f72dcf074e3e2@syzkaller.appspotmail.com
First crash: 873d, last: now
Cause bisection: introduced by (bisect log) :
commit 8d5459c11f548131ce48b2fbf45cccc5c382558f
Author: Jan Kara <jack@suse.cz>
Date: Fri May 20 11:14:02 2022 +0000

  ext4: improve write performance with disabled delalloc

Crash: kernel BUG in submit_bh_wbc (log)
Repro: C syz .config
  
Fix bisection: fixed by (bisect log) :
commit 32b9fb9a67ec70bbe3afe931b0ea44203150a49a
Author: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Date: Mon Sep 18 10:45:50 2023 +0000

  ext4: mark buffer new if it is unwritten to avoid stale data exposure

  
Bug presence (2)
Date Name Commit Repro Result
2024/03/17 lts (merge base) 883d1a956208 C [report] kernel BUG in submit_bh_wbc
2024/03/31 upstream (ToT) 18737353cca0 C Didn't crash
Similar bugs (10)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 kernel BUG in submit_bh_wbc origin:lts-only -1 C done 19 516d 944d 3/3 fixed on 2024/07/20 06:27
upstream kernel BUG at fs/buffer.c:LINE! nilfs -1 C done error 567 574d 2756d 25/29 fixed on 2024/04/10 03:59
upstream kernel BUG in submit_bh_wbc (2) udf -1 C done 123 453d 558d 27/29 fixed on 2024/08/14 03:44
linux-4.14 kernel BUG at fs/buffer.c:LINE! -1 C error 59 988d 2383d 0/1 upstream: reported C repro on 2019/04/27 19:47
linux-6.1 kernel BUG in submit_bh_wbc (2) origin:lts-only -1 C inconclusive 228 1d02h 466d 0/3 upstream: reported C repro on 2024/07/26 16:49
linux-4.19 kernel BUG at fs/buffer.c:LINE! (2) udf ext4 -1 C error 31 995d 1809d 0/1 upstream: reported C repro on 2020/11/21 07:48
android-54 kernel BUG at fs/buffer.c:LINE! ext4 -1 C 4762 163d 2114d 0/2 upstream: reported C repro on 2020/01/21 13:12
upstream kernel BUG in submit_bh_wbc (3) nilfs fs -1 C done 18 379d 386d 28/29 fixed on 2024/11/12 23:31
linux-5.15 kernel BUG in submit_bh_wbc -1 C error 8 606d 884d 0/3 auto-obsoleted due to no activity on 2024/06/16 14:58
upstream kernel BUG in submit_bh_wbc nilfs -1 C done 10 559d 568d 25/29 fixed on 2024/04/24 18:26
Fix bisection attempts (2)
Created Duration User Patch Repo Result
2024/03/11 21:14 3h12m bisect fix android14-6.1 OK (1) job log
2023/07/28 15:24 1h02m bisect fix android14-6.1 OK (0) job log log

Sample crash report:
------------[ cut here ]------------
kernel BUG at fs/buffer.c:2714!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 470 Comm: kmmpd-loop0 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:submit_bh_wbc+0x4c9/0x4f0 fs/buffer.c:2714
Code: c3 89 d9 80 e1 07 80 c1 03 38 c1 0f 8c bd fe ff ff 48 89 df e8 18 36 e8 ff e9 b0 fe ff ff e8 8e d1 a3 ff 0f 0b e8 87 d1 a3 ff <0f> 0b e8 80 d1 a3 ff 0f 0b e8 79 d1 a3 ff 0f 0b e8 72 d1 a3 ff 0f
RSP: 0018:ffffc90000e17ca0 EFLAGS: 00010293
RAX: ffffffff81cc37d9 RBX: 0000000000000000 RCX: ffff88811d035100
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90000e17cf0 R08: dffffc0000000000 R09: ffffed1021d73055
R10: ffffed1021d73055 R11: 1ffff11021d73054 R12: 0000000000000000
R13: 1ffff11021d73054 R14: ffff88810eb982a0 R15: 0000000000003801
FS:  0000000000000000(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b32c63fff CR3: 00000001117ec000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 submit_bh+0x1f/0x30 fs/buffer.c:2755
 write_mmp_block_thawed+0x34a/0x4c0 fs/ext4/mmp.c:51
 write_mmp_block+0x138/0x2b0 fs/ext4/mmp.c:67
 kmmpd+0x215/0x950 fs/ext4/mmp.c:246
 kthread+0x281/0x320 kernel/kthread.c:386
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:submit_bh_wbc+0x4c9/0x4f0 fs/buffer.c:2714
Code: c3 89 d9 80 e1 07 80 c1 03 38 c1 0f 8c bd fe ff ff 48 89 df e8 18 36 e8 ff e9 b0 fe ff ff e8 8e d1 a3 ff 0f 0b e8 87 d1 a3 ff <0f> 0b e8 80 d1 a3 ff 0f 0b e8 79 d1 a3 ff 0f 0b e8 72 d1 a3 ff 0f
RSP: 0018:ffffc90000e17ca0 EFLAGS: 00010293
RAX: ffffffff81cc37d9 RBX: 0000000000000000 RCX: ffff88811d035100
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90000e17cf0 R08: dffffc0000000000 R09: ffffed1021d73055
R10: ffffed1021d73055 R11: 1ffff11021d73054 R12: 0000000000000000
R13: 1ffff11021d73054 R14: ffff88810eb982a0 R15: 0000000000003801
FS:  0000000000000000(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fb976456000 CR3: 000000011e4c5000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

Crashes (2249):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/09/03 13:39 android14-6.1 79ccb6ecf51e 96a211bc .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (clean fs)] ci2-android-6-1 kernel BUG in submit_bh_wbc
2025/07/12 10:38 android14-6.1 e2deb0b42a3a 3cda49cf .config strace log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (clean fs)] ci2-android-6-1 kernel BUG in submit_bh_wbc
2025/06/15 19:48 android14-6.1 6246d345f550 5f4b362d .config strace log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (clean fs)] ci2-android-6-1 kernel BUG in submit_bh_wbc
2025/06/08 14:58 android14-6.1 7af56ffc913d 4826c28e .config strace log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-android-6-1 kernel BUG in submit_bh_wbc
2025/05/25 16:07 android14-6.1 3c6d0251e1fb ed351ea7 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (clean fs)] ci2-android-6-1 kernel BUG in submit_bh_wbc
2025/01/26 16:54 android14-6.1 ef4fb40b87a9 9fbd772e .config strace log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-android-6-1 kernel BUG in submit_bh_wbc
2024/12/16 06:57 android14-6.1 22b7ded8b55b 7cbfbb3a .config strace log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-android-6-1 kernel BUG in submit_bh_wbc
2024/11/30 07:55 android14-6.1 a887a44ace2a 68914665 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-android-6-1 kernel BUG in submit_bh_wbc
2024/11/21 19:03 android14-6.1 51bee181735e 4b25d554 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-android-6-1 kernel BUG in submit_bh_wbc
2024/10/08 00:13 android14-6.1 0e8b65e41ffd d7906eff .config strace log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-android-6-1 kernel BUG in submit_bh_wbc
2024/09/25 06:24 android14-6.1 5c7d0d4f4a38 5643e0e9 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-android-6-1 kernel BUG in submit_bh_wbc
2024/08/20 20:36 android14-6.1 edca080b95df 9f0ab3fb .config strace log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-android-6-1 kernel BUG in submit_bh_wbc
2024/03/17 12:15 android14-6.1 ef39f76e4d24 d615901c .config strace log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-android-6-1 kernel BUG in submit_bh_wbc
2023/10/24 12:09 android14-6.1 8a67c0609445 af8d2e46 .config strace log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-android-6-1 kernel BUG in submit_bh_wbc
2023/09/24 09:56 android14-6.1 060ebb378d1c 0b6a67ac .config strace log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-android-6-1 kernel BUG in submit_bh_wbc
2023/06/15 00:46 android14-6.1 60662882b7bd 76decb82 .config strace log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-android-6-1 kernel BUG in submit_bh_wbc
2023/06/15 00:18 android14-6.1 60662882b7bd 76decb82 .config strace log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-android-6-1 kernel BUG in submit_bh_wbc
2025/11/04 20:22 android14-6.1 616b19ad1f68 686bf657 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 kernel BUG in submit_bh_wbc
2025/11/03 19:46 android14-6.1 3e2aa22eb7df 686bf657 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 kernel BUG in submit_bh_wbc
2025/11/02 08:47 android14-6.1 3e2aa22eb7df 2c50b6a9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 kernel BUG in submit_bh_wbc
2025/10/31 01:41 android14-6.1 64f5109443a1 2c50b6a9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 kernel BUG in submit_bh_wbc
2025/10/30 22:08 android14-6.1 64f5109443a1 2c50b6a9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 kernel BUG in submit_bh_wbc
2025/10/30 18:28 android14-6.1 64f5109443a1 2c50b6a9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 kernel BUG in submit_bh_wbc
2025/10/29 11:03 android14-6.1 7ca912bfce3d fd2207e7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 kernel BUG in submit_bh_wbc
2025/10/29 10:47 android14-6.1 7ca912bfce3d fd2207e7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 kernel BUG in submit_bh_wbc
2025/10/28 10:31 android14-6.1 7ca912bfce3d fd2207e7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 kernel BUG in submit_bh_wbc
2025/10/27 12:28 android14-6.1 22c0b7236c43 fd2207e7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 kernel BUG in submit_bh_wbc
2025/10/26 23:28 android14-6.1 22c0b7236c43 c0460fcd .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 kernel BUG in submit_bh_wbc
2025/10/26 06:51 android14-6.1 22c0b7236c43 c0460fcd .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 kernel BUG in submit_bh_wbc
2025/10/25 21:24 android14-6.1 22c0b7236c43 c0460fcd .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 kernel BUG in submit_bh_wbc
2025/10/25 06:45 android14-6.1 22c0b7236c43 c0460fcd .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 kernel BUG in submit_bh_wbc
2025/10/22 04:32 android14-6.1 22c0b7236c43 252fbbad .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 kernel BUG in submit_bh_wbc
2025/10/22 03:09 android14-6.1 22c0b7236c43 252fbbad .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 kernel BUG in submit_bh_wbc
2025/10/20 13:42 android14-6.1 22c0b7236c43 1c8c8cd8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 kernel BUG in submit_bh_wbc
2025/10/20 03:45 android14-6.1 22c0b7236c43 1c8c8cd8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 kernel BUG in submit_bh_wbc
2025/10/20 00:39 android14-6.1 22c0b7236c43 1c8c8cd8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 kernel BUG in submit_bh_wbc
2025/10/17 09:16 android14-6.1 93de8c8efa80 7adf5298 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 kernel BUG in submit_bh_wbc
2025/10/15 16:27 android14-6.1 ce7ac91b1e9d 19568248 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 kernel BUG in submit_bh_wbc
2025/10/15 07:35 android14-6.1 ce7ac91b1e9d b6605ba8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 kernel BUG in submit_bh_wbc
2025/10/14 17:49 android14-6.1 11f4a3092db9 b6605ba8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 kernel BUG in submit_bh_wbc
2025/10/14 16:09 android14-6.1 11f4a3092db9 b6605ba8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 kernel BUG in submit_bh_wbc
2025/10/12 15:48 android14-6.1 11f4a3092db9 ff1712fe .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 kernel BUG in submit_bh_wbc
2025/10/10 19:50 android14-6.1 1729ceebf41a ff1712fe .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 kernel BUG in submit_bh_wbc
2025/10/10 00:07 android14-6.1 1257aa4519ee ff1712fe .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 kernel BUG in submit_bh_wbc
2025/10/07 22:00 android14-6.1 1257aa4519ee 7e2882b3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 kernel BUG in submit_bh_wbc
2025/10/07 12:23 android14-6.1 1257aa4519ee 8ef35d49 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 kernel BUG in submit_bh_wbc
2025/10/06 23:04 android14-6.1 1257aa4519ee 8ef35d49 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 kernel BUG in submit_bh_wbc
2025/10/04 01:05 android14-6.1 775e02ce538c 49379ee0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 kernel BUG in submit_bh_wbc
2025/10/03 22:24 android14-6.1 775e02ce538c 49379ee0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 kernel BUG in submit_bh_wbc
2025/10/03 16:35 android14-6.1 f6787ec80e17 49379ee0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 kernel BUG in submit_bh_wbc
2025/10/02 12:05 android14-6.1 f6787ec80e17 49379ee0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 kernel BUG in submit_bh_wbc
2025/10/01 23:36 android14-6.1 f6787ec80e17 267f56c6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 kernel BUG in submit_bh_wbc
2025/10/01 00:05 android14-6.1 f6787ec80e17 65a0eece .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 kernel BUG in submit_bh_wbc
2025/09/30 15:25 android14-6.1 f6787ec80e17 65a0eece .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 kernel BUG in submit_bh_wbc
2025/09/29 19:51 android14-6.1 f6787ec80e17 86341da6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 kernel BUG in submit_bh_wbc
2025/09/29 11:03 android14-6.1 5303560ee8cf 86341da6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 kernel BUG in submit_bh_wbc
2025/09/28 12:37 android14-6.1 5303560ee8cf 001c9061 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 kernel BUG in submit_bh_wbc
2025/09/25 23:46 android14-6.1 48c8410fc61f 0abd0691 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 kernel BUG in submit_bh_wbc
2025/09/25 03:25 android14-6.1 48c8410fc61f 0abd0691 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 kernel BUG in submit_bh_wbc
2025/09/24 17:15 android14-6.1 48c8410fc61f 0abd0691 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 kernel BUG in submit_bh_wbc
2025/09/24 04:43 android14-6.1 f8638596656f 0abd0691 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 kernel BUG in submit_bh_wbc
2025/09/24 04:43 android14-6.1 f8638596656f 0abd0691 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 kernel BUG in submit_bh_wbc
2025/09/23 16:15 android14-6.1 f8638596656f e667a34f .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 kernel BUG in submit_bh_wbc
2025/09/23 05:27 android14-6.1 f8638596656f 0ac7291c .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 kernel BUG in submit_bh_wbc
2025/09/22 16:22 android14-6.1 51833209bdd5 0ac7291c .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 kernel BUG in submit_bh_wbc
2023/06/15 00:02 android14-6.1 60662882b7bd 76decb82 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 kernel BUG in submit_bh_wbc
* Struck through repros no longer work on HEAD.