syzbot


kernel BUG in end_page_writeback

Status: upstream: reported C repro on 2022/12/30 20:15
Subsystems: nilfs2
[Documentation on labels]
Reported-by: syzbot+6d72effc948a9d1029aa@syzkaller.appspotmail.com
First crash: 705d, last: 641d
Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 kernel BUG in end_page_writeback origin:lts-only C done 6 577d 627d 3/3 fixed on 2023/06/07 17:22
android-5-10 kernel BUG in end_page_writeback f2fs C error inconclusive 3 616d 667d 2/2 fixed on 2023/06/30 00:53
android-54 kernel BUG in end_page_writeback f2fs C 8 40d 667d 0/2 upstream: reported C repro on 2023/02/06 23:18
Fix bisection attempts (2)
Created Duration User Patch Repo Result
2023/03/04 16:36 21m bisect fix linux-4.14.y OK (0) job log log
2023/02/02 16:13 22m bisect fix linux-4.14.y OK (0) job log log

Sample crash report:
audit: type=1800 audit(1672431232.541:2): pid=7994 uid=0 auid=4294967295 ses=4294967295 op="collect_data" cause="failed(directio)" comm="syz-executor392" name="bus" dev="loop0" ino=18 res=0
NILFS (loop0): segctord starting. Construction interval = 5 seconds, CP frequency < 30 seconds
------------[ cut here ]------------
kernel BUG at mm/filemap.c:1154!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
Modules linked in:
CPU: 0 PID: 7999 Comm: segctord Not tainted 4.14.302-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
task: ffff8880b29562c0 task.stack: ffff888095fb8000
RIP: 0010:end_page_writeback+0x1a2/0x1c0 mm/filemap.c:1154
RSP: 0018:ffff888095fbfb70 EFLAGS: 00010297
RAX: ffff8880b29562c0 RBX: ffffea000269a740 RCX: 1ffff1101652ad6e
RDX: 0000000000000000 RSI: 0000000000000002 RDI: 0000000000000282
RBP: ffffea000269a740 R08: ffffffff8b9dca70 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000000 R12: ffffea000269a760
R13: ffffea00027e3b20 R14: dffffc0000000000 R15: ffff88808e364400
FS:  0000000000000000(0000) GS:ffff8880ba400000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055e4bb6d02c8 CR3: 0000000098c95000 CR4: 00000000003406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 nilfs_segctor_complete_write fs/nilfs2/segment.c:1855 [inline]
 nilfs_segctor_wait fs/nilfs2/segment.c:1942 [inline]
 nilfs_segctor_do_construct+0x4bf4/0x79c0 fs/nilfs2/segment.c:2105
 nilfs_segctor_construct+0x6db/0x8e0 fs/nilfs2/segment.c:2394
 nilfs_segctor_thread_construct fs/nilfs2/segment.c:2502 [inline]
 nilfs_segctor_thread+0x3ad/0xdb0 fs/nilfs2/segment.c:2586
 kthread+0x30d/0x420 kernel/kthread.c:232
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:406
Code: 89 e7 e8 f2 76 16 00 e9 53 ff ff ff 48 89 df e8 e5 76 16 00 e9 ce fe ff ff 4c 89 e7 e8 d8 76 16 00 e9 90 fe ff ff e8 ce b5 ec ff <0f> 0b 48 89 ef e8 c4 76 16 00 e9 4d ff ff ff 66 66 2e 0f 1f 84 
RIP: end_page_writeback+0x1a2/0x1c0 mm/filemap.c:1154 RSP: ffff888095fbfb70
---[ end trace 0d62e84782b49dfd ]---

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/12/30 20:15 linux-4.14.y c4215ee4771b 44712fbc .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-4-14 kernel BUG in end_page_writeback
* Struck through repros no longer work on HEAD.