[v5.15] divide error in flush_commit_list (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: c52b9710c83d Linux 5.15.156
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=165ef237180000
kernel config: https://syzkaller.appspot.com/x/.config?x=567b6ddc38438433
dashboard link: https://syzkaller.appspot.com/bug?extid=1d3966bdb5a057da328e
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/1bd4b9969373/disk-c52b9710.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/10509e89bd25/vmlinux-c52b9710.xz
kernel image: https://storage.googleapis.com/syzbot-assets/a623a4c52eb5/bzImage-c52b9710.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+1d3966...@syzkaller.appspotmail.com

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


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