divide error in do_journal_end (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 7d7d1c0a Linux 4.14.232
git tree: linux-4.14.y
console output: https://syzkaller.appspot.com/x/log.txt?x=13d110a5d00000
kernel config: https://syzkaller.appspot.com/x/.config?x=17ee8a0e183900d8
dashboard link: https://syzkaller.appspot.com/bug?extid=5b433e82ccf79a4ea8a3
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1206fbcdd00000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=171d21f1d00000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+5b433e...@syzkaller.appspotmail.com

reiserfs: using flush barriers
REISERFS (device loop0): journal params: device loop0, size 8192, journal first block 10, max trans len 1024, max batch 900, max commit age 30, max trans age 30
REISERFS (device loop0): checking transaction log (loop0)
REISERFS (device loop0): Using rupasov hash to sort names
REISERFS (device loop0): Created .reiserfs_priv - reserved for xattr storage.
divide error: 0000 [#1] PREEMPT SMP KASAN
Modules linked in:
CPU: 1 PID: 7970 Comm: syz-executor152 Not tainted 4.14.232-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8880b4ec0640 task.stack: ffff8880a1ca0000
RIP: 0010:do_journal_end+0x212e/0x4260 fs/reiserfs/journal.c:4201
RSP: 0018:ffff8880a1ca7ab8 EFLAGS: 00010246
RAX: 0000000000000005 RBX: dffffc0000000000 RCX: ffff8880965f2cc0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90005afd048 R08: ffffffff8b9b54c0 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: ffff888099ee3000
R13: 0000000000000001 R14: ffff8880b3ea6140 R15: 0000000000001000
FS: 0000000001413300(0000) GS:ffff8880ba500000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000004b51d0 CR3: 00000000a10fc000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
reiserfs_sync_fs+0xbb/0xd0 fs/reiserfs/super.c:78
__sync_filesystem fs/sync.c:39 [inline]
sync_filesystem fs/sync.c:67 [inline]
sync_filesystem+0x185/0x230 fs/sync.c:48
generic_shutdown_super+0x70/0x370 fs/super.c:432
kill_block_super+0x95/0xe0 fs/super.c:1161
deactivate_locked_super+0x6c/0xd0 fs/super.c:319
deactivate_super+0x7f/0xa0 fs/super.c:350
cleanup_mnt+0x186/0x2c0 fs/namespace.c:1183
task_work_run+0x11f/0x190 kernel/task_work.c:113
exit_task_work include/linux/task_work.h:22 [inline]
do_exit+0xa44/0x2850 kernel/exit.c:868
do_group_exit+0x100/0x2e0 kernel/exit.c:965
SYSC_exit_group kernel/exit.c:976 [inline]
SyS_exit_group+0x19/0x20 kernel/exit.c:974
do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x442ed9
RSP: 002b:00007fff46b20338 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00000000004b42f0 RCX: 0000000000442ed9
RDX: 000000000000003c RSI: 00000000000000e7 RDI: 0000000000000001
RBP: 0000000000000001 R08: ffffffffffffffc0 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000004b42f0
R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000001
Code: 95 c2 45 84 d3 0f 85 6a 15 00 00 83 e2 07 40 38 d6 0f 9e c2 40 84 f6 40 0f 95 c6 40 84 f2 0f 85 51 15 00 00 41 8b 7c 24 14 31 d2 <48> f7 f7 48 8d 79 18 4a 8d 34 0a 48 89 f8 48 c1 e8 03 80 3c 18
RIP: do_journal_end+0x212e/0x4260 fs/reiserfs/journal.c:4201 RSP: ffff8880a1ca7ab8
---[ end trace c83264a7eb83c969 ]---


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