------------[ cut here ]------------
WARNING: CPU: 0 PID: 3841 at kernel/locking/lockdep.c:704 look_up_lock_class kernel/locking/lockdep.c:704 [inline]
WARNING: CPU: 0 PID: 3841 at kernel/locking/lockdep.c:704 register_lock_class+0xcac/0x1340 kernel/locking/lockdep.c:726
Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 3841 Comm: syzkaller100826 Not tainted 4.9.85-g6e463bb #46
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801bf54f4f8 ffffffff81d955d9 ffffffff83a480c0 ffff8801bf54f5d0
 ffffffff83a5b900 ffffffff81236cfc 0000000000000009 ffff8801bf54f5c0
 ffffffff8142f571 0000000041b58ab3 ffffffff8418b388 ffffffff8142f3b5
Call Trace:
 [<ffffffff81d955d9>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81d955d9>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff8142f571>] panic+0x1bc/0x3a8 kernel/panic.c:179
 [<ffffffff811311c4>] __warn+0x1c4/0x1e0 kernel/panic.c:542
 [<ffffffff8113142c>] warn_slowpath_null+0x2c/0x40 kernel/panic.c:585
 [<ffffffff81236cfc>] look_up_lock_class kernel/locking/lockdep.c:704 [inline]
 [<ffffffff81236cfc>] register_lock_class+0xcac/0x1340 kernel/locking/lockdep.c:726
 [<ffffffff8123c19c>] __lock_acquire+0x16c/0x3640 kernel/locking/lockdep.c:3233
 [<ffffffff812400ae>] lock_acquire+0x12e/0x410 kernel/locking/lockdep.c:3756
 [<ffffffff838b494a>] __raw_spin_lock_bh include/linux/spinlock_api_smp.h:137 [inline]
 [<ffffffff838b494a>] _raw_spin_lock_bh+0x3a/0x50 kernel/locking/spinlock.c:175
 [<ffffffff82ee5013>] spin_lock_bh include/linux/spinlock.h:307 [inline]
 [<ffffffff82ee5013>] lock_sock_nested+0x43/0x120 net/core/sock.c:2503
 [<ffffffff8320e60a>] lock_sock include/net/sock.h:1404 [inline]
 [<ffffffff8320e60a>] do_ip_getsockopt+0x16a/0x15f0 net/ipv4/ip_sockglue.c:1317
 [<ffffffff8320fb1f>] ip_getsockopt+0x8f/0x180 net/ipv4/ip_sockglue.c:1545
 [<ffffffff832bb845>] udp_getsockopt+0x45/0x80 net/ipv4/udp.c:2155
 [<ffffffff82edee85>] sock_common_getsockopt+0x95/0xd0 net/core/sock.c:2665
 [<ffffffff82edc48a>] SYSC_getsockopt net/socket.c:1803 [inline]
 [<ffffffff82edc48a>] SyS_getsockopt+0x14a/0x230 net/socket.c:1785
 [<ffffffff81006504>] do_syscall_64+0x1a4/0x490 arch/x86/entry/common.c:282
 [<ffffffff838b5413>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb
Dumping ftrace buffer:
   (ftrace buffer empty)
Kernel Offset: disabled
Rebooting in 86400 seconds..