syzbot


divide error in flush_commit_list (2)

Status: upstream: reported on 2024/04/25 09:33
Reported-by: syzbot+1d3966bdb5a057da328e@syzkaller.appspotmail.com
First crash: 9d22h, last: 9d22h
Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream divide error in flush_commit_list reiserfs 24 128d 503d 0/26 auto-obsoleted due to no activity on 2024/04/06 13:39
linux-4.19 divide error in flush_commit_list 1 441d 441d 0/1 upstream: reported on 2023/02/18 21:03
linux-5.15 divide error in flush_commit_list 1 367d 367d 0/3 auto-obsoleted due to no activity on 2023/08/23 09:10

Sample crash report:
divide error: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 8601 Comm: syz-executor.3 Not tainted 5.15.156-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
RIP: 0010:flush_commit_list+0xb4e/0x1ec0 fs/reiserfs/journal.c:1049
Code: c0 4c 8b ac 24 a8 00 00 00 0f 85 d5 01 00 00 4c 89 e0 48 c1 e8 03 0f b6 04 30 84 c0 0f 85 ec 01 00 00 41 8b 0f 48 89 d8 31 d2 <48> f7 f1 49 89 d7 49 83 c6 18 4c 89 f0 48 c1 e8 03 80 3c 30 00 74
RSP: 0018:ffffc900034c7a20 EFLAGS: 00010246
RAX: 00000000000000e7 RBX: 00000000000000e7 RCX: 0000000000000000
RDX: 0000000000000000 RSI: dffffc0000000000 RDI: 0000000000040000
RBP: ffffc900034c7ba0 R08: dffffc0000000000 R09: ffffed100971df4c
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff888054e20017
R13: ffff88807c19a018 R14: ffff888056c5a000 R15: ffff888054e20014
FS:  00007f4d36f506c0(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000002005a000 CR3: 000000004b0ec000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 do_journal_end+0x3bb3/0x4650 fs/reiserfs/journal.c:4372
 reiserfs_sync_fs+0xca/0x140 fs/reiserfs/super.c:78
 iterate_supers+0x127/0x1e0 fs/super.c:705
 ksys_sync+0xd7/0x1c0 fs/sync.c:104
 __do_sys_sync+0xa/0x10 fs/sync.c:113
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f4d38a61ea9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f4d36f500c8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007f4d38b902c0 RCX: 00007f4d38a61ea9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f4d38aae4a4 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000006e R14: 00007f4d38b902c0 R15: 00007ffe6ee2b4d8
 </TASK>
Modules linked in:
---[ end trace 4faff2effb8036f2 ]---
RIP: 0010:flush_commit_list+0xb4e/0x1ec0 fs/reiserfs/journal.c:1049
Code: c0 4c 8b ac 24 a8 00 00 00 0f 85 d5 01 00 00 4c 89 e0 48 c1 e8 03 0f b6 04 30 84 c0 0f 85 ec 01 00 00 41 8b 0f 48 89 d8 31 d2 <48> f7 f1 49 89 d7 49 83 c6 18 4c 89 f0 48 c1 e8 03 80 3c 30 00 74
RSP: 0018:ffffc900034c7a20 EFLAGS: 00010246
RAX: 00000000000000e7 RBX: 00000000000000e7 RCX: 0000000000000000
RDX: 0000000000000000 RSI: dffffc0000000000 RDI: 0000000000040000
RBP: ffffc900034c7ba0 R08: dffffc0000000000 R09: ffffed100971df4c
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff888054e20017
R13: ffff88807c19a018 R14: ffff888056c5a000 R15: ffff888054e20014
FS:  00007f4d36f506c0(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2bf25000 CR3: 000000004b0ec000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	c0 4c 8b ac 24       	rorb   $0x24,-0x54(%rbx,%rcx,4)
   5:	a8 00                	test   $0x0,%al
   7:	00 00                	add    %al,(%rax)
   9:	0f 85 d5 01 00 00    	jne    0x1e4
   f:	4c 89 e0             	mov    %r12,%rax
  12:	48 c1 e8 03          	shr    $0x3,%rax
  16:	0f b6 04 30          	movzbl (%rax,%rsi,1),%eax
  1a:	84 c0                	test   %al,%al
  1c:	0f 85 ec 01 00 00    	jne    0x20e
  22:	41 8b 0f             	mov    (%r15),%ecx
  25:	48 89 d8             	mov    %rbx,%rax
  28:	31 d2                	xor    %edx,%edx
* 2a:	48 f7 f1             	div    %rcx <-- trapping instruction
  2d:	49 89 d7             	mov    %rdx,%r15
  30:	49 83 c6 18          	add    $0x18,%r14
  34:	4c 89 f0             	mov    %r14,%rax
  37:	48 c1 e8 03          	shr    $0x3,%rax
  3b:	80 3c 30 00          	cmpb   $0x0,(%rax,%rsi,1)
  3f:	74                   	.byte 0x74

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/04/25 09:32 linux-5.15.y c52b9710c83d 8bdc0f22 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan divide error in flush_commit_list
* Struck through repros no longer work on HEAD.