syzbot has found a reproducer for the following issue on: HEAD commit: 5dc4c995db9e Linux 6.2-rc4 git tree: upstream console+strace: https://syzkaller.appspot.com/x/log.txt?x=17104a36480000 kernel config: https://syzkaller.appspot.com/x/.config?x=2d1e01fb80d3df97 dashboard link: https://syzkaller.appspot.com/bug?extid=74b838cfa47fc9554471 compiler: Debian clang version 13.0.1-++20220126092033+75e33f71c2da-1~exp1~20220126212112.63, GNU ld (GNU Binutils for Debian) 2.35.2 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=10169b86480000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=10b27089480000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/e52acf94631e/disk-5dc4c995.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/8ead5c940574/vmlinux-5dc4c995.xz kernel image: https://storage.googleapis.com/syzbot-assets/f6b43b71bf31/bzImage-5dc4c995.xz mounted in repro: https://storage.googleapis.com/syzbot-assets/964c239d9caf/mount_0.gz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+74b838cfa47fc9554471@xxxxxxxxxxxxxxxxxxxxxxxxx divide error: 0000 [#1] PREEMPT SMP KASAN CPU: 1 PID: 5068 Comm: syz-executor317 Not tainted 6.2.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 RIP: 0010:do_journal_end+0x1822/0x4a30 fs/reiserfs/journal.c:4091 Code: 04 28 84 c0 0f 85 f7 2b 00 00 4a 8d 5c 33 01 4c 89 e0 48 c1 e8 03 42 8a 04 28 84 c0 0f 85 ff 2b 00 00 41 8b 0f 48 89 d8 31 d2 <48> f7 f1 48 89 d3 48 03 5c 24 20 48 8b 84 24 d8 00 00 00 42 80 3c RSP: 0018:ffffc90003b7f820 EFLAGS: 00010246 RAX: 0000000000000003 RBX: 0000000000000003 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff888029c4f000 RBP: ffffc90003b7fa90 R08: dffffc0000000000 R09: ffff888029c4f000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff88807a8e9017 R13: dffffc0000000000 R14: 0000000000000002 R15: ffff88807a8e9014 FS: 0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000005fdeb8 CR3: 0000000026e6b000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> reiserfs_sync_fs+0xbb/0x130 fs/reiserfs/super.c:78 sync_filesystem+0xe8/0x220 fs/sync.c:56 generic_shutdown_super+0x6b/0x310 fs/super.c:474 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 exit_task_work include/linux/task_work.h:38 [inline] do_exit+0x644/0x2150 kernel/exit.c:867 do_group_exit+0x1fd/0x2b0 kernel/exit.c:1012 __do_sys_exit_group kernel/exit.c:1023 [inline] __se_sys_exit_group kernel/exit.c:1021 [inline] __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1021 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f24fcf1bad9 Code: Unable to access opcode bytes at 0x7f24fcf1baaf. RSP: 002b:00007ffda2e53128 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 00007f24fcf91350 RCX: 00007f24fcf1bad9 RDX: 000000000000003c RSI: 00000000000000e7 RDI: 0000000000000001 RBP: 0000000000000001 R08: ffffffffffffffc0 R09: 00007f24fcf8be40 R10: 000000000001ff01 R11: 0000000000000246 R12: 00007f24fcf91350 R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000001 </TASK> Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:do_journal_end+0x1822/0x4a30 fs/reiserfs/journal.c:4091 Code: 04 28 84 c0 0f 85 f7 2b 00 00 4a 8d 5c 33 01 4c 89 e0 48 c1 e8 03 42 8a 04 28 84 c0 0f 85 ff 2b 00 00 41 8b 0f 48 89 d8 31 d2 <48> f7 f1 48 89 d3 48 03 5c 24 20 48 8b 84 24 d8 00 00 00 42 80 3c RSP: 0018:ffffc90003b7f820 EFLAGS: 00010246 RAX: 0000000000000003 RBX: 0000000000000003 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff888029c4f000 RBP: ffffc90003b7fa90 R08: dffffc0000000000 R09: ffff888029c4f000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff88807a8e9017 R13: dffffc0000000000 R14: 0000000000000002 R15: ffff88807a8e9014 FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000056252d1db088 CR3: 000000001da35000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 04 28 add $0x28,%al 2: 84 c0 test %al,%al 4: 0f 85 f7 2b 00 00 jne 0x2c01 a: 4a 8d 5c 33 01 lea 0x1(%rbx,%r14,1),%rbx f: 4c 89 e0 mov %r12,%rax 12: 48 c1 e8 03 shr $0x3,%rax 16: 42 8a 04 28 mov (%rax,%r13,1),%al 1a: 84 c0 test %al,%al 1c: 0f 85 ff 2b 00 00 jne 0x2c21 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: 48 89 d3 mov %rdx,%rbx 30: 48 03 5c 24 20 add 0x20(%rsp),%rbx 35: 48 8b 84 24 d8 00 00 mov 0xd8(%rsp),%rax 3c: 00 3d: 42 rex.X 3e: 80 .byte 0x80 3f: 3c .byte 0x3c
