bond0 (unregistering): Releasing backup interface bond_slave_1
bond0 (unregistering): Releasing backup interface bond_slave_0
bond0 (unregistering): Released all slaves
------------[ cut here ]------------
WARNING: CPU: 1 PID: 22 at net/netfilter/core.c:151 nf_unregister_net_hook+0x28a/0x3c0 net/netfilter/core.c:151
nf_unregister_net_hook: hook not found!
Kernel panic - not syncing: panic_on_warn set ...

CPU: 1 PID: 22 Comm: kworker/u4:1 Not tainted 4.9.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: netns cleanup_net
 ffff88012b24f890 ffffffff82d7bbd6 ffffffff86088840 ffff88012b24f968
 ffffffff868b3800 ffffffff84d7a09a ffff88012b24f958 ffffffff8163d5d2
 0000000041b58ab3 ffffffff86d6b20d ffffffff8163d41c ffffffff814779f4
Call Trace:
 [<ffffffff82d7bbd6>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff82d7bbd6>] dump_stack+0xe6/0x120 lib/dump_stack.c:51
 [<ffffffff8163d5d2>] panic+0x1b6/0x358 kernel/panic.c:179
 [<ffffffff8135267d>] __warn+0x18d/0x1b0 kernel/panic.c:542
 [<ffffffff81352732>] warn_slowpath_fmt+0x92/0xb0 kernel/panic.c:565
 [<ffffffff84d7a09a>] nf_unregister_net_hook+0x28a/0x3c0 net/netfilter/core.c:151
 [<ffffffff84d7a2f6>] nf_unregister_hook_list net/netfilter/core.c:484 [inline]
 [<ffffffff84d7a2f6>] netfilter_net_exit+0x36/0xa0 net/netfilter/core.c:516
 [<ffffffff84b6b06e>] ops_exit_list.isra.4+0x8e/0x120 net/core/net_namespace.c:136
 [<ffffffff84b6da90>] cleanup_net+0x2d0/0x570 net/core/net_namespace.c:449
 [<ffffffff813a6252>] process_one_work+0x6a2/0x1560 kernel/workqueue.c:2096
 [<ffffffff813a71f1>] worker_thread+0xe1/0x1050 kernel/workqueue.c:2230
 [<ffffffff813b7c8e>] kthread+0x20e/0x2d0 kernel/kthread.c:209
 [<ffffffff85ecb0da>] ret_from_fork+0x2a/0x40 arch/x86/entry/entry_64.S:433
Kernel Offset: disabled