------------[ cut here ]------------ WARNING: CPU: 0 PID: 21825 at net/ipv4/af_inet.c:167 inet_sock_destruct+0x598/0x760 net/ipv4/af_inet.c:167 Kernel panic - not syncing: panic_on_warn set ... CPU: 0 PID: 21825 Comm: syz-executor3 Not tainted 4.9.122-g54068d6 #26 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ffff8801db207cc0 ffffffff81eb8829 ffffffff83c48ac0 00000000ffffffff 0000000000000000 0000000000000000 00000000000000a7 ffff8801db207d80 ffffffff81423f35 0000000041b58ab3 ffffffff843bb838 ffffffff81423d76 Call Trace: [ 658.413463] [] __dump_stack lib/dump_stack.c:15 [inline] [ 658.413463] [] dump_stack+0xc1/0x128 lib/dump_stack.c:51 [] panic+0x1bf/0x3bc kernel/panic.c:179 [] __warn.cold.9+0xc1/0x17f kernel/panic.c:542 [] warn_slowpath_null+0x2c/0x40 kernel/panic.c:585 [] inet_sock_destruct+0x598/0x760 net/ipv4/af_inet.c:167 [] l2tp_tunnel_destruct+0x339/0x590 net/l2tp/l2tp_core.c:1329 [] __sk_destruct+0x55/0x590 net/core/sock.c:1428 [] __rcu_reclaim kernel/rcu/rcu.h:118 [inline] [] rcu_do_batch kernel/rcu/tree.c:2789 [inline] [] invoke_rcu_callbacks kernel/rcu/tree.c:3053 [inline] [] __rcu_process_callbacks kernel/rcu/tree.c:3020 [inline] [] rcu_process_callbacks+0x8ae/0x12b0 kernel/rcu/tree.c:3037 [] __do_softirq+0x210/0x940 kernel/softirq.c:288 [] invoke_softirq kernel/softirq.c:368 [inline] [] irq_exit+0x114/0x150 kernel/softirq.c:409 [] exiting_irq arch/x86/include/asm/apic.h:669 [inline] [] smp_apic_timer_interrupt+0x81/0xa0 arch/x86/kernel/apic/apic.c:962 [] apic_timer_interrupt+0xa0/0xb0 arch/x86/entry/entry_64.S:648 [ 658.542545] [] ? get_next_corpse net/netfilter/nf_conntrack_core.c:1547 [inline] [ 658.542545] [] ? nf_ct_iterate_cleanup+0x238/0x480 net/netfilter/nf_conntrack_core.c:1618 [] local_bh_enable include/linux/bottom_half.h:31 [inline] [] get_next_corpse net/netfilter/nf_conntrack_core.c:1562 [inline] [] nf_ct_iterate_cleanup+0x25f/0x480 net/netfilter/nf_conntrack_core.c:1618 [] masq_device_event+0xa8/0xd0 net/ipv4/netfilter/nf_nat_masquerade_ipv4.c:100 [] notifier_call_chain+0xb4/0x1d0 kernel/notifier.c:93 [] __raw_notifier_call_chain kernel/notifier.c:394 [inline] [] raw_notifier_call_chain+0x2d/0x40 kernel/notifier.c:401 [] call_netdevice_notifiers_info+0x55/0x70 net/core/dev.c:1647 [] call_netdevice_notifiers net/core/dev.c:1663 [inline] [] dev_close_many+0x252/0x380 net/core/dev.c:1456 [] rollback_registered_many+0x268/0x920 net/core/dev.c:6810 [] rollback_registered+0x81/0xb0 net/core/dev.c:6873 [] unregister_netdevice_queue+0x81/0x110 net/core/dev.c:7860 [] unregister_netdevice include/linux/netdevice.h:2458 [inline] [] __tun_detach+0x830/0xa10 drivers/net/tun.c:575 [] tun_detach drivers/net/tun.c:585 [inline] [] tun_chr_close+0x44/0x60 drivers/net/tun.c:2390 [] __fput+0x263/0x700 fs/file_table.c:208 [] ____fput+0x15/0x20 fs/file_table.c:244 [] task_work_run+0x10c/0x180 kernel/task_work.c:116 [] exit_task_work include/linux/task_work.h:21 [inline] [] do_exit+0x9e1/0x27b0 kernel/exit.c:833 [] do_group_exit+0x111/0x340 kernel/exit.c:937 [] SYSC_exit_group kernel/exit.c:948 [inline] [] SyS_exit_group+0x1d/0x20 kernel/exit.c:946 [] do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282 [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb Dumping ftrace buffer: (ftrace buffer empty) Kernel Offset: disabled Rebooting in 86400 seconds..