syzbot


kernel BUG in f2fs_write_end_io (2)

Status: upstream: reported C repro on 2026/05/14 20:19
Subsystems: f2fs
Labels: prio:high
[Documentation on labels]
Reported-by: syzbot+4af46ee83100e99bce09@syzkaller.appspotmail.com
First crash: 33d, last: 16h46m
Cause bisection: failed (error log, bisect log)
  
✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision Error
366ee1f2-650e-4956-a5c6-f3226bf2263d assessment-security DenialOfService: ❌ Exploitable: ❌ FilesystemTrigger: ✅ NetworkTrigger: ❌ PeripheralTrigger: ✅ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ❌ VMGuestTrigger: ❌ VMHostTrigger: ❌ kernel BUG in f2fs_write_end_io (2) 2026/05/17 08:22 2026/05/17 08:23 2026/05/17 09:06 de5aae85e5f28e2fa1c7deefcc24fe286abe5140
Discussions (3)
Title Replies (including bot) Last reply
[syzbot] Monthly f2fs report (Jun 2026) 0 (1) 2026/06/10 04:32
[PATCH] f2fs: don't BUG on node footer mismatch in f2fs_write_end_io 2 (2) 2026/05/17 09:30
[syzbot] [f2fs?] kernel BUG in f2fs_write_end_io (2) 0 (7) 2026/05/17 09:02
Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream kernel BUG in f2fs_write_end_io f2fs -1 C inconclusive 285 39d 437d 29/29 fixed on 2026/05/06 16:40
Last patch testing requests (6)
Created Duration User Patch Repo Result
2026/05/17 09:02 20m chao@kernel.org https://git.kernel.org/pub/scm/linux/kernel/git/chao/linux.git syzbot log
2026/05/17 05:43 19m chao@kernel.org https://git.kernel.org/pub/scm/linux/kernel/git/chao/linux.git bugfix/syzbot log
2026/05/17 03:07 20m chao@kernel.org https://git.kernel.org/pub/scm/linux/kernel/git/chao/linux.git bugfix/syzbot error
2026/05/15 01:55 35m kartikey406@gmail.com patch upstream OK log
2026/05/15 01:00 21m kartikey406@gmail.com patch upstream report log
2026/05/14 23:35 24m kartikey406@gmail.com patch upstream report log

Sample crash report:
------------[ cut here ]------------
kernel BUG at fs/f2fs/data.c:388!
Oops: invalid opcode: 0000 [#1] SMP KASAN PTI
CPU: 1 UID: 0 PID: 31 Comm: ksoftirqd/1 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:f2fs_write_end_io+0x16df/0x1740 fs/f2fs/data.c:388
Code: 20 3c 9b 8b e8 12 0a f7 fc 90 0f 0b e8 0a cc 93 fd 48 8b 3c 24 48 c7 c6 20 3c 9b 8b e8 fa 09 f7 fc 90 0f 0b e8 f2 cb 93 fd 90 <0f> 0b e8 ea cb 93 fd 48 8b 3c 24 48 c7 c6 20 3c 9b 8b e8 da 09 f7
RSP: 0018:ffffc90000a5fb18 EFLAGS: 00010246
RAX: ffffffff8430aade RBX: ffffea0000d91c40 RCX: ffff88801d6b0000
RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000100
RBP: dffffc0000000000 R08: 0000000000000000 R09: 0000000000000100
R10: dffffc0000000000 R11: fffffbfff1f11dff R12: 0000000036471000
R13: ffffea0000d91c80 R14: 000000000000000b R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff888126276000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007eff6352cff8 CR3: 000000002caa2000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 blk_update_request+0x57e/0xe60 block/blk-mq.c:1016
 blk_mq_end_request+0x3e/0x70 block/blk-mq.c:1178
 blk_complete_reqs block/blk-mq.c:1253 [inline]
 blk_done_softirq+0x10a/0x160 block/blk-mq.c:1258
 handle_softirqs+0x1de/0x6d0 kernel/softirq.c:622
 run_ksoftirqd+0x52/0x180 kernel/softirq.c:1076
 smpboot_thread_fn+0x541/0xa50 kernel/smpboot.c:160
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:f2fs_write_end_io+0x16df/0x1740 fs/f2fs/data.c:388
Code: 20 3c 9b 8b e8 12 0a f7 fc 90 0f 0b e8 0a cc 93 fd 48 8b 3c 24 48 c7 c6 20 3c 9b 8b e8 fa 09 f7 fc 90 0f 0b e8 f2 cb 93 fd 90 <0f> 0b e8 ea cb 93 fd 48 8b 3c 24 48 c7 c6 20 3c 9b 8b e8 da 09 f7
RSP: 0018:ffffc90000a5fb18 EFLAGS: 00010246
RAX: ffffffff8430aade RBX: ffffea0000d91c40 RCX: ffff88801d6b0000
RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000100
RBP: dffffc0000000000 R08: 0000000000000000 R09: 0000000000000100
R10: dffffc0000000000 R11: fffffbfff1f11dff R12: 0000000036471000
R13: ffffea0000d91c80 R14: 000000000000000b R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff888126276000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007eff6352cff8 CR3: 000000002caa2000 CR4: 00000000003526f0

Crashes (37):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/05/11 01:43 upstream aa54b1d27fe0 29233ece .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro #1 (corrupt fs)] [mounted in repro #2] ci2-upstream-fs kernel BUG in f2fs_write_end_io
2026/06/12 21:40 upstream 1dadb7e7eb5a 1d2f3589 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in f2fs_write_end_io
2026/06/11 18:46 upstream 9716c086c8e8 d93a6ab6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in f2fs_write_end_io
2026/06/11 18:36 upstream 9716c086c8e8 d93a6ab6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in f2fs_write_end_io
2026/06/09 21:49 upstream 2d3090a8aeb5 c36c07f6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in f2fs_write_end_io
2026/06/08 20:23 upstream 2d3090a8aeb5 656e94c6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in f2fs_write_end_io
2026/06/08 00:39 upstream 33d8d8ec31b5 cc095639 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in f2fs_write_end_io
2026/06/07 00:39 upstream 8e65320d91cd cc095639 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in f2fs_write_end_io
2026/06/06 23:35 upstream 8e65320d91cd cc095639 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in f2fs_write_end_io
2026/06/06 18:46 upstream 8e65320d91cd cc095639 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in f2fs_write_end_io
2026/06/06 04:25 upstream c10130c234c8 cc095639 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in f2fs_write_end_io
2026/06/03 16:00 upstream ba3e43a9e601 234057e5 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in f2fs_write_end_io
2026/06/01 04:14 upstream e43ffb69e043 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in f2fs_write_end_io
2026/06/01 04:13 upstream e43ffb69e043 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in f2fs_write_end_io
2026/06/01 04:12 upstream e43ffb69e043 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in f2fs_write_end_io
2026/06/01 04:12 upstream e43ffb69e043 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in f2fs_write_end_io
2026/06/01 03:35 upstream e43ffb69e043 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in f2fs_write_end_io
2026/06/01 03:28 upstream e43ffb69e043 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in f2fs_write_end_io
2026/05/31 15:17 upstream 174914ea5513 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in f2fs_write_end_io
2026/05/31 08:04 upstream 9d87d0fc8c8e 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in f2fs_write_end_io
2026/05/31 01:52 upstream 9d87d0fc8c8e 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in f2fs_write_end_io
2026/05/31 01:51 upstream 9d87d0fc8c8e 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in f2fs_write_end_io
2026/05/31 01:50 upstream 9d87d0fc8c8e 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in f2fs_write_end_io
2026/05/31 01:50 upstream 9d87d0fc8c8e 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in f2fs_write_end_io
2026/05/31 01:00 upstream 9d87d0fc8c8e 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in f2fs_write_end_io
2026/05/31 00:59 upstream 9d87d0fc8c8e 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in f2fs_write_end_io
2026/05/31 00:59 upstream 9d87d0fc8c8e 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in f2fs_write_end_io
2026/05/29 18:56 upstream 8fde5d1d47f6 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in f2fs_write_end_io
2026/05/29 07:39 upstream 8fde5d1d47f6 4624854e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in f2fs_write_end_io
2026/05/29 07:35 upstream 8fde5d1d47f6 4624854e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in f2fs_write_end_io
2026/05/26 19:34 upstream d60ec36cab33 a3e47276 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in f2fs_write_end_io
2026/05/22 05:39 upstream 6779b50faa56 70ae9b03 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in f2fs_write_end_io
2026/05/21 09:02 upstream 8bc67e4db64a 41b8c833 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in f2fs_write_end_io
2026/05/20 19:11 upstream df685633c3db 62fb93a2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in f2fs_write_end_io
2026/05/19 21:50 upstream ab5fce87a778 223544dc .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in f2fs_write_end_io
2026/05/10 21:32 upstream aa54b1d27fe0 29233ece .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in f2fs_write_end_io
2026/05/10 20:12 upstream aa54b1d27fe0 29233ece .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in f2fs_write_end_io
* Struck through repros no longer work on HEAD.