syzbot


WARNING: bad unlock balance in jfs_commit_inode

Status: upstream: reported on 2025/01/19 07:45
Reported-by: syzbot+13c3b498a6ca7374deed@syzkaller.appspotmail.com
First crash: 17d, last: 17d

Sample crash report:
=====================================
WARNING: bad unlock balance detected!
5.15.176-syzkaller #0 Not tainted
-------------------------------------
kworker/u4:12/6133 is trying to release lock (&jfs_ip->commit_mutex) at:
[<ffff80000991ed60>] jfs_commit_inode+0x2d4/0x4f8 fs/jfs/inode.c:111
but there are no more locks to release!

other info that might help us debug this:
2 locks held by kworker/u4:12/6133:
 #0: ffff0000c21d8138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x66c/0x11b8 kernel/workqueue.c:2283
 #1: ffff800021247c00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6ac/0x11b8 kernel/workqueue.c:2285

stack backtrace:
CPU: 1 PID: 6133 Comm: kworker/u4:12 Not tainted 5.15.176-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
Workqueue: writeback wb_workfn (flush-7:4)
Call trace:
 dump_backtrace+0x0/0x530 arch/arm64/kernel/stacktrace.c:152
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:216
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x108/0x170 lib/dump_stack.c:106
 dump_stack+0x1c/0x58 lib/dump_stack.c:113
 print_unlock_imbalance_bug+0x250/0x2a4 kernel/locking/lockdep.c:5065
 lock_release+0x4b8/0xa1c kernel/locking/lockdep.c:5643
 __mutex_unlock_slowpath+0xe0/0x6d4 kernel/locking/mutex.c:851
 mutex_unlock+0x8c/0xe0 kernel/locking/mutex.c:536
 jfs_commit_inode+0x2d4/0x4f8 fs/jfs/inode.c:111
 jfs_write_inode+0x128/0x200 fs/jfs/inode.c:132
 write_inode fs/fs-writeback.c:1495 [inline]
 __writeback_single_inode+0x584/0x13a4 fs/fs-writeback.c:1705
 writeback_sb_inodes+0x94c/0x1654 fs/fs-writeback.c:1930
 wb_writeback+0x3fc/0xfc8 fs/fs-writeback.c:2104
 wb_do_writeback fs/fs-writeback.c:2247 [inline]
 wb_workfn+0x3a4/0x1070 fs/fs-writeback.c:2288
 process_one_work+0x790/0x11b8 kernel/workqueue.c:2310
 worker_thread+0x910/0x1034 kernel/workqueue.c:2457
 kthread+0x37c/0x45c kernel/kthread.c:334
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:870

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/01/19 07:45 linux-5.15.y 4735586da88e f2cb035c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING: bad unlock balance in jfs_commit_inode
* Struck through repros no longer work on HEAD.