syzbot


divide error in flush_journal_list (2)

Status: upstream: reported on 2023/09/06 17:01
Subsystems: reiserfs
[Documentation on labels]
Reported-by: syzbot+b933ce9cda6c5c8ac3f4@syzkaller.appspotmail.com
First crash: 179d, last: 96d
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [reiserfs?] divide error in flush_journal_list (2) 0 (1) 2023/09/06 17:01
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream divide error in flush_journal_list reiserfs 1 361d 357d 0/26 auto-obsoleted due to no activity on 2023/07/02 17:58

Sample crash report:
divide error: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 28956 Comm: syz-executor.5 Not tainted 6.7.0-rc2-syzkaller-00095-gd3fa86b1a7b4 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
RIP: 0010:flush_journal_list+0x1045/0x1c80 fs/reiserfs/journal.c:1591
Code: c0 0f 85 eb 0a 00 00 4f 8d 7c 3e 02 48 89 e8 48 c1 e8 03 42 0f b6 04 20 84 c0 4d 89 e6 0f 85 ee 0a 00 00 8b 0b 4c 89 f8 31 d2 <48> f7 f1 48 89 d3 43 0f b6 44 35 00 84 c0 0f 85 f2 0a 00 00 48 8b
RSP: 0018:ffffc9000a5cf1f8 EFLAGS: 00010246
RAX: 00000000000001e6 RBX: ffff888081b9e014 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffff888081b9e017 R08: ffffffff823a56db R09: 1ffff11007a97063
R10: dffffc0000000000 R11: ffffed1007a97064 R12: dffffc0000000000
R13: 1ffff11005282617 R14: dffffc0000000000 R15: 00000000000001e6
FS:  00007f5d2b23c6c0(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000203c1000 CR3: 000000001d57d000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 flush_used_journal_lists+0x1256/0x15d0 fs/reiserfs/journal.c:1828
 do_journal_end+0x3d5a/0x4b50
 do_journal_begin_r+0x970/0x1030
 journal_begin+0x14c/0x360 fs/reiserfs/journal.c:3254
 reiserfs_fill_super+0x1853/0x2620 fs/reiserfs/super.c:2104
 mount_bdev+0x237/0x300 fs/super.c:1650
 legacy_get_tree+0xef/0x190 fs/fs_context.c:662
 vfs_get_tree+0x8c/0x2a0 fs/super.c:1771
 do_new_mount+0x28f/0xae0 fs/namespace.c:3337
 do_mount fs/namespace.c:3677 [inline]
 __do_sys_mount fs/namespace.c:3886 [inline]
 __se_sys_mount+0x2d9/0x3c0 fs/namespace.c:3863
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x45/0x110 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x63/0x6b
RIP: 0033:0x7f5d2a47e1ea
Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 de 09 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 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:00007f5d2b23bee8 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f5d2b23bf80 RCX: 00007f5d2a47e1ea
RDX: 0000000020001100 RSI: 0000000020000000 RDI: 00007f5d2b23bf40
RBP: 0000000020001100 R08: 00007f5d2b23bf80 R09: 0000000000000804
R10: 0000000000000804 R11: 0000000000000202 R12: 0000000020000000
R13: 00007f5d2b23bf40 R14: 00000000000010fe R15: 0000000020000100
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:flush_journal_list+0x1045/0x1c80 fs/reiserfs/journal.c:1591
Code: c0 0f 85 eb 0a 00 00 4f 8d 7c 3e 02 48 89 e8 48 c1 e8 03 42 0f b6 04 20 84 c0 4d 89 e6 0f 85 ee 0a 00 00 8b 0b 4c 89 f8 31 d2 <48> f7 f1 48 89 d3 43 0f b6 44 35 00 84 c0 0f 85 f2 0a 00 00 48 8b
RSP: 0018:ffffc9000a5cf1f8 EFLAGS: 00010246
RAX: 00000000000001e6 RBX: ffff888081b9e014 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffff888081b9e017 R08: ffffffff823a56db R09: 1ffff11007a97063
R10: dffffc0000000000 R11: ffffed1007a97064 R12: dffffc0000000000
R13: 1ffff11005282617 R14: dffffc0000000000 R15: 00000000000001e6
FS:  00007f5d2b23c6c0(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555557375788 CR3: 000000001d57d000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	c0 0f 85             	rorb   $0x85,(%rdi)
   3:	eb 0a                	jmp    0xf
   5:	00 00                	add    %al,(%rax)
   7:	4f 8d 7c 3e 02       	lea    0x2(%r14,%r15,1),%r15
   c:	48 89 e8             	mov    %rbp,%rax
   f:	48 c1 e8 03          	shr    $0x3,%rax
  13:	42 0f b6 04 20       	movzbl (%rax,%r12,1),%eax
  18:	84 c0                	test   %al,%al
  1a:	4d 89 e6             	mov    %r12,%r14
  1d:	0f 85 ee 0a 00 00    	jne    0xb11
  23:	8b 0b                	mov    (%rbx),%ecx
  25:	4c 89 f8             	mov    %r15,%rax
  28:	31 d2                	xor    %edx,%edx
* 2a:	48 f7 f1             	div    %rcx <-- trapping instruction
  2d:	48 89 d3             	mov    %rdx,%rbx
  30:	43 0f b6 44 35 00    	movzbl 0x0(%r13,%r14,1),%eax
  36:	84 c0                	test   %al,%al
  38:	0f 85 f2 0a 00 00    	jne    0xb30
  3e:	48                   	rex.W
  3f:	8b                   	.byte 0x8b

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/11/24 08:31 upstream d3fa86b1a7b4 5b429f39 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs divide error in flush_journal_list
2023/09/02 16:51 upstream 0468be89b3fa 696ea0d2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs divide error in flush_journal_list
* Struck through repros no longer work on HEAD.