[syzbot] divide error in flush_commit_list

From: syzbot
Date: Sun Dec 18 2022 - 10:58:51 EST


Hello,

syzbot found the following issue on:

HEAD commit: e2ca6ba6ba01 Merge tag 'mm-stable-2022-12-13' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=158718d7880000
kernel config: https://syzkaller.appspot.com/x/.config?x=276eb8ff64eb2c27
dashboard link: https://syzkaller.appspot.com/bug?extid=32134c00ff57e0343b6b
compiler: Debian clang version 13.0.1-++20220126092033+75e33f71c2da-1~exp1~20220126212112.63, GNU ld (GNU Binutils for Debian) 2.35.2

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/8aad47431ccd/disk-e2ca6ba6.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/382636835ba9/vmlinux-e2ca6ba6.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ac62c9f6a7cf/bzImage-e2ca6ba6.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+32134c00ff57e0343b6b@xxxxxxxxxxxxxxxxxxxxxxxxx

divide error: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 5334 Comm: syz-executor.0 Not tainted 6.1.0-syzkaller-09941-ge2ca6ba6ba01 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
RIP: 0010:flush_commit_list+0x971/0x1bb0 fs/reiserfs/journal.c:1051
Code: 30 84 c0 4c 8b 6c 24 78 0f 85 c7 01 00 00 48 89 e8 48 c1 e8 03 0f b6 04 30 84 c0 0f 85 da 01 00 00 41 8b 0c 24 4c 89 f0 31 d2 <48> f7 f1 48 89 d3 49 83 c7 18 4c 89 f8 48 c1 e8 03 80 3c 30 00 74
RSP: 0018:ffffc90003c3f788 EFLAGS: 00010246
RAX: 000000000000003d RBX: ffff88802ded300c RCX: 0000000000000000
RDX: 0000000000000000 RSI: dffffc0000000000 RDI: ffff88807664bb40
RBP: ffff88802ded3017 R08: dffffc0000000000 R09: ffffed100ecc9769
R10: ffffed100ecc9769 R11: 1ffff1100ecc9768 R12: ffff88802ded3014
R13: ffff888075848018 R14: 000000000000003d R15: ffff888075c33000
FS: 0000555556d5d400(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f82d3460000 CR3: 0000000047a19000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
do_journal_end+0x3858/0x4a30 fs/reiserfs/journal.c:4302
do_journal_release+0x15f/0x4c0 fs/reiserfs/journal.c:1917
journal_release+0x1b/0x30 fs/reiserfs/journal.c:1971
reiserfs_put_super+0x245/0x4e0 fs/reiserfs/super.c:616
generic_shutdown_super+0x130/0x310 fs/super.c:492
kill_block_super+0x79/0xd0 fs/super.c:1386
deactivate_locked_super+0xa7/0xf0 fs/super.c:332
cleanup_mnt+0x494/0x520 fs/namespace.c:1291
task_work_run+0x243/0x300 kernel/task_work.c:179
resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
exit_to_user_mode_loop+0x124/0x150 kernel/entry/common.c:171
exit_to_user_mode_prepare+0xb2/0x140 kernel/entry/common.c:203
__syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline]
syscall_exit_to_user_mode+0x26/0x60 kernel/entry/common.c:296
do_syscall_64+0x49/0xb0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fb24988d547
Code: ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffef1d23d28 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007fb24988d547
RDX: 00007ffef1d23dfa RSI: 000000000000000a RDI: 00007ffef1d23df0
RBP: 00007ffef1d23df0 R08: 00000000ffffffff R09: 00007ffef1d23bc0
R10: 0000555556d5e873 R11: 0000000000000246 R12: 00007fb2498e6b24
R13: 00007ffef1d24eb0 R14: 0000555556d5e810 R15: 00007ffef1d24ef0
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:flush_commit_list+0x971/0x1bb0 fs/reiserfs/journal.c:1051
Code: 30 84 c0 4c 8b 6c 24 78 0f 85 c7 01 00 00 48 89 e8 48 c1 e8 03 0f b6 04 30 84 c0 0f 85 da 01 00 00 41 8b 0c 24 4c 89 f0 31 d2 <48> f7 f1 48 89 d3 49 83 c7 18 4c 89 f8 48 c1 e8 03 80 3c 30 00 74
RSP: 0018:ffffc90003c3f788 EFLAGS: 00010246
RAX: 000000000000003d RBX: ffff88802ded300c RCX: 0000000000000000
RDX: 0000000000000000 RSI: dffffc0000000000 RDI: ffff88807664bb40
RBP: ffff88802ded3017 R08: dffffc0000000000 R09: ffffed100ecc9769
R10: ffffed100ecc9769 R11: 1ffff1100ecc9768 R12: ffff88802ded3014
R13: ffff888075848018 R14: 000000000000003d R15: ffff888075c33000
FS: 0000555556d5d400(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f50d71fe000 CR3: 0000000047a19000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
0: 30 84 c0 4c 8b 6c 24 xor %al,0x246c8b4c(%rax,%rax,8)
7: 78 0f js 0x18
9: 85 c7 test %eax,%edi
b: 01 00 add %eax,(%rax)
d: 00 48 89 add %cl,-0x77(%rax)
10: e8 48 c1 e8 03 callq 0x3e8c15d
15: 0f b6 04 30 movzbl (%rax,%rsi,1),%eax
19: 84 c0 test %al,%al
1b: 0f 85 da 01 00 00 jne 0x1fb
21: 41 8b 0c 24 mov (%r12),%ecx
25: 4c 89 f0 mov %r14,%rax
28: 31 d2 xor %edx,%edx
* 2a: 48 f7 f1 div %rcx <-- trapping instruction
2d: 48 89 d3 mov %rdx,%rbx
30: 49 83 c7 18 add $0x18,%r15
34: 4c 89 f8 mov %r15,%rax
37: 48 c1 e8 03 shr $0x3,%rax
3b: 80 3c 30 00 cmpb $0x0,(%rax,%rsi,1)
3f: 74 .byte 0x74


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