SELinux: unrecognized netlink message: protocol=4 nlmsg_type=24 sclass=netlink_tcpdiag_socket pig=16733 comm=syz-executor4

=====================================
[ BUG: bad unlock balance detected! ]
4.9.75-g8910fa5 #19 Not tainted
-------------------------------------
syz-executor7/16727 is trying to release lock (mrt_lock) at:
[<ffffffff834e6574>] ipmr_mfc_seq_stop+0xe4/0x140 net/ipv6/ip6mr.c:553
but there are no more locks to release!

other info that might help us debug this:
1 lock held by syz-executor7/16727:
 #0:  (&p->lock){+.+.+.}, at: [<ffffffff815e74bd>] seq_read+0xdd/0x1290 fs/seq_file.c:178

stack backtrace:
CPU: 1 PID: 16727 Comm: syz-executor7 Not tainted 4.9.75-g8910fa5 #19
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801c023f8d8 ffffffff81d93049 ffffffff849b67b8 ffff8801d1cac800
 ffffffff834e6574 ffffffff849b67b8 ffff8801d1cad088 ffff8801c023f908
 ffffffff81236bf4 dffffc0000000000 ffffffff849b67b8 00000000ffffffff
Call Trace:
 [<ffffffff81d93049>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81d93049>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff81236bf4>] print_unlock_imbalance_bug+0x174/0x1a0 kernel/locking/lockdep.c:3398
 [<ffffffff8123f6c8>] __lock_release kernel/locking/lockdep.c:3540 [inline]
 [<ffffffff8123f6c8>] lock_release+0x6f8/0xb80 kernel/locking/lockdep.c:3775
 [<ffffffff838b05fa>] __raw_read_unlock include/linux/rwlock_api_smp.h:225 [inline]
 [<ffffffff838b05fa>] _raw_read_unlock+0x1a/0x50 kernel/locking/spinlock.c:255
 [<ffffffff834e6574>] ipmr_mfc_seq_stop+0xe4/0x140 net/ipv6/ip6mr.c:553
 [<ffffffff815e7e63>] seq_read+0xa83/0x1290 fs/seq_file.c:283
 [<ffffffff816c0b5f>] proc_reg_read+0xef/0x170 fs/proc/inode.c:202
 [<ffffffff8156b481>] do_loop_readv_writev.part.17+0x141/0x1e0 fs/read_write.c:714
 [<ffffffff815703a2>] do_loop_readv_writev fs/read_write.c:1105 [inline]
 [<ffffffff815703a2>] compat_do_readv_writev+0x522/0x760 fs/read_write.c:1099
 [<ffffffff815706c3>] compat_readv+0xe3/0x150 fs/read_write.c:1128
 [<ffffffff815709d6>] do_compat_preadv64+0xd6/0x100 fs/read_write.c:1177
 [<ffffffff81572e1b>] C_SYSC_preadv fs/read_write.c:1197 [inline]
 [<ffffffff81572e1b>] compat_SyS_preadv+0x3b/0x50 fs/read_write.c:1191
 [<ffffffff81006fc7>] do_syscall_32_irqs_on arch/x86/entry/common.c:322 [inline]
 [<ffffffff81006fc7>] do_fast_syscall_32+0x2f7/0x890 arch/x86/entry/common.c:384
 [<ffffffff838b2334>] entry_SYSENTER_compat+0x74/0x83 arch/x86/entry/entry_64_compat.S:127
device syz2 entered promiscuous mode