syzbot


WARNING: bad unlock balance in do_wait
Status: auto-closed as invalid on 2022/02/04 09:11
Reported-by: syzbot+a80f3868e983754a0e6e@syzkaller.appspotmail.com
First crash: 199d, last: 199d

Sample crash report:
=====================================
WARNING: bad unlock balance detected!
5.15.0-syzkaller #0 Not tainted
-------------------------------------
systemd/1 is trying to release lock (tasklist_lock) at:
[<ffffffff81465d58>] do_wait+0x4f8/0xce0 kernel/exit.c:1533
but there are no more locks to release!

other info that might help us debug this:
no locks held by systemd/1.

stack backtrace:
CPU: 1 PID: 1 Comm: systemd Not tainted 5.15.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 print_unlock_imbalance_bug include/trace/events/lock.h:58 [inline]
 __lock_release kernel/locking/lockdep.c:5294 [inline]
 lock_release.cold+0x49/0x4e kernel/locking/lockdep.c:5645
 __raw_read_unlock include/linux/rwlock_api_smp.h:223 [inline]
 _raw_read_unlock+0x12/0x40 kernel/locking/spinlock.c:260
 do_wait+0x4f8/0xce0 kernel/exit.c:1533
 kernel_waitid+0x275/0x370 kernel/exit.c:1608
 __do_sys_waitid+0x235/0x2d0 kernel/exit.c:1621
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f90ea653141
Code: 55 53 89 cd 49 89 d4 89 fb 48 83 ec 18 e8 d7 d3 03 00 44 89 ee 41 89 c1 89 df 45 31 c0 4c 63 d5 4c 89 e2 b8 f7 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 1b 44 89 cf 89 44 24 0c e8 0b d4 03 00 8b 44
RSP: 002b:00007ffff57619a0 EFLAGS: 00000246 ORIG_RAX: 00000000000000f7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f90ea653141
RDX: 00007ffff5761a00 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000001000005 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000001000005 R11: 0000000000000246 R12: 00007ffff5761a00
R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000002
 </TASK>

Crashes (1):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci-upstream-kasan-gce-root 2021/11/06 09:11 upstream d4439a1189f9 4c1be0be .config log report info WARNING: bad unlock balance in do_wait