=====================================
[ BUG: bad unlock balance detected! ]
4.9.67-gf26d3c7 #106 Not tainted
-------------------------------------
syz-executor0/12250 is trying to release lock ([   78.740751] device lo entered promiscuous mode
mrt_lock) at:
but there are no more locks to release!

other info that might help us debug this:
2 locks held by syz-executor0/12250:
 #0:  (&f->f_pos_lock){+.+.+.}, at: [<ffffffff815cf8df>] __fdget_pos+0x9f/0xc0 fs/file.c:781
 #1:  (&p->lock){+.+.+.}, at: [<ffffffff815e4cdd>] seq_read+0xdd/0x1290 fs/seq_file.c:178

stack backtrace:
CPU: 0 PID: 12250 Comm: syz-executor0 Not tainted 4.9.67-gf26d3c7 #106
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801c6cd78e8 ffffffff81d906e9 ffffffff849ae8f8 ffff8801c6d16000
 ffffffff834dec54 ffffffff849ae8f8 ffff8801c6d16888 ffff8801c6cd7918
 ffffffff812353f4 dffffc0000000000 ffffffff849ae8f8 00000000ffffffff
Call Trace:
 [<ffffffff81d906e9>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81d906e9>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff812353f4>] print_unlock_imbalance_bug+0x174/0x1a0 kernel/locking/lockdep.c:3398
 [<ffffffff8123dec8>] __lock_release kernel/locking/lockdep.c:3540 [inline]
 [<ffffffff8123dec8>] lock_release+0x6f8/0xb80 kernel/locking/lockdep.c:3775
 [<ffffffff838a951a>] __raw_read_unlock include/linux/rwlock_api_smp.h:225 [inline]
 [<ffffffff838a951a>] _raw_read_unlock+0x1a/0x50 kernel/locking/spinlock.c:255
 [<ffffffff834dec54>] ipmr_mfc_seq_stop+0xe4/0x140 net/ipv6/ip6mr.c:553
 [<ffffffff815e5683>] seq_read+0xa83/0x1290 fs/seq_file.c:283
 [<ffffffff816be32f>] proc_reg_read+0xef/0x170 fs/proc/inode.c:202
 [<ffffffff81568cb1>] do_loop_readv_writev.part.17+0x141/0x1e0 fs/read_write.c:714
 [<ffffffff8156cb20>] do_loop_readv_writev fs/read_write.c:880 [inline]
 [<ffffffff8156cb20>] do_readv_writev+0x520/0x750 fs/read_write.c:874
 [<ffffffff8156cdd4>] vfs_readv+0x84/0xc0 fs/read_write.c:898
 [<ffffffff8156cef6>] do_readv+0xe6/0x250 fs/read_write.c:924
 [<ffffffff815703e7>] SYSC_readv fs/read_write.c:1011 [inline]
 [<ffffffff815703e7>] SyS_readv+0x27/0x30 fs/read_write.c:1008
 [<ffffffff838a9985>] entry_SYSCALL_64_fastpath+0x23/0xc6
device lo left promiscuous mode
device gre0 entered promiscuous mode
FAULT_FLAG_ALLOW_RETRY missing 30
FAULT_FLAG_ALLOW_RETRY missing 30
CPU: 1 PID: 12280 Comm: syz-executor4 Not tainted 4.9.67-gf26d3c7 #106
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801ca75f8d0 ffffffff81d906e9 ffff8801ca75fbb0 0000000000000000
 ffff8801c6034a10 ffff8801ca75faa0 ffff8801c6034900 ffff8801ca75fac8
 ffffffff8165e307 ffff8801ca75f938 ffff8801ca75fa20 00000001ca757067
Call Trace:
 [<ffffffff81d906e9>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81d906e9>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff8165e307>] handle_userfault+0xa37/0x1300 fs/userfaultfd.c:323
 [<ffffffff814cd5f1>] do_anonymous_page mm/memory.c:2747 [inline]
 [<ffffffff814cd5f1>] handle_pte_fault mm/memory.c:3488 [inline]
 [<ffffffff814cd5f1>] __handle_mm_fault mm/memory.c:3577 [inline]
 [<ffffffff814cd5f1>] handle_mm_fault+0x1fd1/0x2530 mm/memory.c:3614
 [<ffffffff810dd452>] __do_page_fault+0x5c2/0xd40 arch/x86/mm/fault.c:1406
 [<ffffffff810ddbf7>] do_page_fault+0x27/0x30 arch/x86/mm/fault.c:1469
 [<ffffffff838aab58>] page_fault+0x28/0x30 arch/x86/entry/entry_64.S:1012
 [<ffffffff838a9985>] entry_SYSCALL_64_fastpath+0x23/0xc6
CPU: 0 PID: 12289 Comm: syz-executor4 Not tainted 4.9.67-gf26d3c7 #106
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801a724f860 ffffffff81d906e9 ffff8801a724fb40 0000000000000000
 ffff8801c6034a10 ffff8801a724fa30 ffff8801c6034900 ffff8801a724fa58
 ffffffff8165e307 ffffffff811b6f31 ffff8801a724f9b0 00000001ca757067
Call Trace:
 [<ffffffff81d906e9>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81d906e9>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff8165e307>] handle_userfault+0xa37/0x1300 fs/userfaultfd.c:323
 [<ffffffff814cd5f1>] do_anonymous_page mm/memory.c:2747 [inline]
 [<ffffffff814cd5f1>] handle_pte_fault mm/memory.c:3488 [inline]
 [<ffffffff814cd5f1>] __handle_mm_fault mm/memory.c:3577 [inline]
 [<ffffffff814cd5f1>] handle_mm_fault+0x1fd1/0x2530 mm/memory.c:3614
 [<ffffffff810dd452>] __do_page_fault+0x5c2/0xd40 arch/x86/mm/fault.c:1406
 [<ffffffff810ddbf7>] do_page_fault+0x27/0x30 arch/x86/mm/fault.c:1469
 [<ffffffff838aab58>] page_fault+0x28/0x30 arch/x86/entry/entry_64.S:1012
 [<ffffffff8116786d>] SyS_rt_sigtimedwait+0x2d/0x40 kernel/signal.c:2819
 [<ffffffff838a9985>] entry_SYSCALL_64_fastpath+0x23/0xc6
FAULT_FLAG_ALLOW_RETRY missing 30
FAULT_FLAG_ALLOW_RETRY missing 30
CPU: 0 PID: 12280 Comm: syz-executor4 Not tainted 4.9.67-gf26d3c7 #106
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801ca75f8d0 ffffffff81d906e9 ffff8801ca75fbb0 0000000000000000
 ffff8801cf2c4290 ffff8801ca75faa0 ffff8801cf2c4180 ffff8801ca75fac8
 ffffffff8165e307 ffff8801ca75f918 ffff8801ca75fa20 00000001d011f067
Call Trace:
 [<ffffffff81d906e9>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81d906e9>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff8165e307>] handle_userfault+0xa37/0x1300 fs/userfaultfd.c:323
 [<ffffffff814cd5f1>] do_anonymous_page mm/memory.c:2747 [inline]
 [<ffffffff814cd5f1>] handle_pte_fault mm/memory.c:3488 [inline]
 [<ffffffff814cd5f1>] __handle_mm_fault mm/memory.c:3577 [inline]
 [<ffffffff814cd5f1>] handle_mm_fault+0x1fd1/0x2530 mm/memory.c:3614
 [<ffffffff810dd452>] __do_page_fault+0x5c2/0xd40 arch/x86/mm/fault.c:1406
 [<ffffffff810ddbf7>] do_page_fault+0x27/0x30 arch/x86/mm/fault.c:1469
 [<ffffffff838aab58>] page_fault+0x28/0x30 arch/x86/entry/entry_64.S:1012
 [<ffffffff838a9985>] entry_SYSCALL_64_fastpath+0x23/0xc6
FAULT_FLAG_ALLOW_RETRY missing 30
CPU: 1 PID: 12280 Comm: syz-executor4 Not tainted 4.9.67-gf26d3c7 #106
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801ca75f8a0 ffffffff81d906e9 ffff8801ca75fb80 0000000000000000
 ffff8801cf2c4290 ffff8801ca75fa70 ffff8801cf2c4180 ffff8801ca75fa98
 ffffffff8165e307 ffffffff00000002 ffff8801000000e4 0000000000000000
Call Trace:
 [<ffffffff81d906e9>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81d906e9>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff8165e307>] handle_userfault+0xa37/0x1300 fs/userfaultfd.c:323
 [<ffffffff814cd5f1>] do_anonymous_page mm/memory.c:2747 [inline]
 [<ffffffff814cd5f1>] handle_pte_fault mm/memory.c:3488 [inline]
 [<ffffffff814cd5f1>] __handle_mm_fault mm/memory.c:3577 [inline]
 [<ffffffff814cd5f1>] handle_mm_fault+0x1fd1/0x2530 mm/memory.c:3614
 [<ffffffff810dd452>] __do_page_fault+0x5c2/0xd40 arch/x86/mm/fault.c:1406
 [<ffffffff810ddbf7>] do_page_fault+0x27/0x30 arch/x86/mm/fault.c:1469
 [<ffffffff838aab58>] page_fault+0x28/0x30 arch/x86/entry/entry_64.S:1012
 [<ffffffff81ba8c2c>] copy_from_user arch/x86/include/asm/uaccess.h:702 [inline]
 [<ffffffff81ba8c2c>] SYSC_mq_open ipc/mqueue.c:782 [inline]
 [<ffffffff81ba8c2c>] SyS_mq_open+0x18c/0x940 ipc/mqueue.c:769
 [<ffffffff838a9985>] entry_SYSCALL_64_fastpath+0x23/0xc6
CPU: 0 PID: 12363 Comm: syz-executor4 Not tainted 4.9.67-gf26d3c7 #106
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801c7557860 ffffffff81d906e9 ffff8801c7557b40 0000000000000000
 ffff8801cf2c4290 ffff8801c7557a30 ffff8801cf2c4180 ffff8801c7557a58
 ffffffff8165e307 ffffffff811b6f31 ffff8801c75579b0 00000001d011f067
Call Trace:
 [<ffffffff81d906e9>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81d906e9>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff8165e307>] handle_userfault+0xa37/0x1300 fs/userfaultfd.c:323
 [<ffffffff814cd5f1>] do_anonymous_page mm/memory.c:2747 [inline]
 [<ffffffff814cd5f1>] handle_pte_fault mm/memory.c:3488 [inline]
 [<ffffffff814cd5f1>] __handle_mm_fault mm/memory.c:3577 [inline]
 [<ffffffff814cd5f1>] handle_mm_fault+0x1fd1/0x2530 mm/memory.c:3614
 [<ffffffff810dd452>] __do_page_fault+0x5c2/0xd40 arch/x86/mm/fault.c:1406
 [<ffffffff810ddbf7>] do_page_fault+0x27/0x30 arch/x86/mm/fault.c:1469
 [<ffffffff838aab58>] page_fault+0x28/0x30 arch/x86/entry/entry_64.S:1012
 [<ffffffff8116786d>] SyS_rt_sigtimedwait+0x2d/0x40 kernel/signal.c:2819
 [<ffffffff838a9985>] entry_SYSCALL_64_fastpath+0x23/0xc6
device gre0 entered promiscuous mode