syzbot


WARNING: bad unlock balance detected!

Status: closed as invalid on 2018/01/30 23:45
Subsystems: net
[Documentation on labels]
Reported-by: syzbot+118d758e6670956425a5384acd064695670f84c2@syzkaller.appspotmail.com
First crash: 2327d, last: 2327d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream WARNING: bad unlock balance detected! (3) net syz done unreliable 6 1287d 1887d 0/26 auto-obsoleted due to no activity on 2022/09/26 08:14
upstream WARNING: bad unlock balance detected! (2) net syz 1 1905d 1905d 0/26 closed as invalid on 2019/02/06 08:32

Sample crash report:
=====================================
WARNING: bad unlock balance detected!
4.15.0-rc3+ #217 Not tainted
-------------------------------------
syz-executor3/19522 is trying to release lock (mrt_lock) at:
[<00000000adc671f1>] ipmr_mfc_seq_stop+0xe1/0x130 net/ipv6/ip6mr.c:553
but there are no more locks to release!

other info that might help us debug this:
2 locks held by syz-executor3/19522:
 #0:  (&f->f_pos_lock){+.+.}, at: [<00000000cd36f0f9>] __fdget_pos+0x131/0x1a0 fs/file.c:770
 #1:  (&p->lock){+.+.}, at: [<00000000c93d2595>] seq_lseek+0x58/0x3c0 fs/seq_file.c:321

stack backtrace:
CPU: 0 PID: 19522 Comm: syz-executor3 Not tainted 4.15.0-rc3+ #217
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x194/0x257 lib/dump_stack.c:53
 print_unlock_imbalance_bug+0x12f/0x140 kernel/locking/lockdep.c:3561
 __lock_release kernel/locking/lockdep.c:3775 [inline]
 lock_release+0x5f9/0xda0 kernel/locking/lockdep.c:4023
 __raw_read_unlock include/linux/rwlock_api_smp.h:225 [inline]
 _raw_read_unlock+0x1a/0x30 kernel/locking/spinlock.c:255
 ipmr_mfc_seq_stop+0xe1/0x130 net/ipv6/ip6mr.c:553
 traverse+0x3bc/0xa00 fs/seq_file.c:135
 seq_lseek+0x136/0x3c0 fs/seq_file.c:331
 proc_reg_llseek+0xf1/0x160 fs/proc/inode.c:203
 vfs_llseek fs/read_write.c:300 [inline]
 SYSC_lseek fs/read_write.c:313 [inline]
 SyS_lseek+0xf1/0x170 fs/read_write.c:304
 entry_SYSCALL_64_fastpath+0x1f/0x96
RIP: 0033:0x452a39
RSP: 002b:00007fda08e4bc58 EFLAGS: 00000212 ORIG_RAX: 0000000000000008
RAX: ffffffffffffffda RBX: 00007fda08e4c700 RCX: 0000000000452a39
RDX: 0000000000000001 RSI: 0000000000000020 RDI: 0000000000000013
RBP: 0000000000a6f880 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000212 R12: 0000000000000000
R13: 0000000000a6f7ff R14: 00007fda08e4c9c0 R15: 0000000000000002
BUG: scheduling while atomic: syz-executor3/19522/0x00000000
INFO: lockdep is turned off.
Modules linked in:
Kernel panic - not syncing: scheduling while atomic

CPU: 0 PID: 19522 Comm: syz-executor3 Not tainted 4.15.0-rc3+ #217
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x194/0x257 lib/dump_stack.c:53
 panic+0x1e4/0x41c kernel/panic.c:183
 __schedule_bug+0x11f/0x130 kernel/sched/core.c:3177
 schedule_debug kernel/sched/core.c:3194 [inline]
 __schedule+0x131c/0x2060 kernel/sched/core.c:3299
 schedule+0xf5/0x430 kernel/sched/core.c:3434
 exit_to_usermode_loop+0x1d1/0x310 arch/x86/entry/common.c:151
 prepare_exit_to_usermode arch/x86/entry/common.c:195 [inline]
 syscall_return_slowpath+0x490/0x550 arch/x86/entry/common.c:264
 entry_SYSCALL_64_fastpath+0x94/0x96
RIP: 0033:0x452a39
RSP: 002b:00007fda08e4bc58 EFLAGS: 00000212 ORIG_RAX: 0000000000000008
RAX: 0000000000000040 RBX: 00000000007580d8 RCX: 0000000000452a39
RDX: 0000000000000001 RSI: 0000000000000020 RDI: 0000000000000013
RBP: 000000000000038a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000212 R12: 00000000006f3590
R13: 00000000ffffffff R14: 00007fda08e4c6d4 R15: 0000000000000002
Dumping ftrace buffer:
   (ftrace buffer empty)
Kernel Offset: disabled
Rebooting in 86400 seconds..

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2017/12/11 06:34 upstream 50c4c4e268a2 5ad0ce95 .config console log report ci-upstream-kasan-gce
* Struck through repros no longer work on HEAD.