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kernel BUG at net/core/skbuff.c:2208!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
Modules linked in:
CPU: 1 PID: 14284 Comm: kworker/u4:15 Not tainted 4.4.174+ #4
Workqueue: netns cleanup_net
task: ffff8801d467c740 task.stack: ffff8801d4dd8000
RIP: 0010:[<ffffffff821f6ac7>]  [<ffffffff821f6ac7>] skb_copy_and_csum_bits+0x6e7/0x800 net/core/skbuff.c:2208
RSP: 0018:ffff8801db7072b8  EFLAGS: 00010206
RAX: ffff8801d467c740 RBX: 0000000000000000 RCX: 1ffff10016535059
RDX: 0000000000000100 RSI: ffffffff821f6ac7 RDI: ffff8800b29a82c8
RBP: ffff8801db707348 R08: 0000000000000000 R09: 0000000000000000
R10: 000000000000003c R11: ffff8800b3cf6b5f R12: 000000008398c726
R13: ffff8801d19c0500 R14: ffff8800b29a82c0 R15: 000000000000003c
FS:  0000000000000000(0000) GS:ffff8801db700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000a6fda8 CR3: 00000000a679a000 CR4: 00000000001606b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:
 ffff8801d4ec9d48 ffffffff8244588d ffffffff812582dd ffff8800b3cf68e8
 0000003c8271bb16 ffffffff810e1a8a ffffffff8271b24e ffffffff8271a59d
 ffff8801d4ec9d44 ffffffff8232392c 000001e88398c726 ffff8801d4ec9c80
Call Trace:
 <IRQ> 
 [<ffffffff82493d6f>] icmp_glue_bits+0x7f/0x1e0 net/ipv4/icmp.c:344
 [<ffffffff823caf41>] __ip_append_data.isra.0+0x1e91/0x2a20 net/ipv4/ip_output.c:1045
 [<ffffffff823cbbbc>] ip_append_data.part.0+0xec/0x160 net/ipv4/ip_output.c:1195
 [<ffffffff823d07a9>] ip_append_data+0x69/0x90 net/ipv4/ip_output.c:1184
 [<ffffffff82493979>] icmp_push_reply+0x199/0x510 net/ipv4/icmp.c:362
 [<ffffffff824950fa>] icmp_send+0xaca/0x1410 net/ipv4/icmp.c:727
 [<ffffffff823cbde4>] ip_fragment net/ipv4/ip_output.c:511 [inline]
 [<ffffffff823cbde4>] ip_fragment.constprop.0+0x1b4/0x200 net/ipv4/ip_output.c:498
 [<ffffffff823cc1e9>] ip_finish_output+0x3b9/0xc60 net/ipv4/ip_output.c:286
 [<ffffffff823d04a7>] NF_HOOK_COND include/linux/netfilter.h:240 [inline]
 [<ffffffff823d04a7>] ip_output+0x227/0x4c0 net/ipv4/ip_output.c:362
 [<ffffffff823cd21c>] dst_output include/net/dst.h:498 [inline]
 [<ffffffff823cd21c>] ip_local_out+0x9c/0x180 net/ipv4/ip_output.c:119
 [<ffffffff823ce58c>] ip_queue_xmit+0x89c/0x1ab0 net/ipv4/ip_output.c:461
 [<ffffffff82431dd4>] __tcp_transmit_skb+0x1904/0x2cf0 net/ipv4/tcp_output.c:1034
 [<ffffffff8243c54a>] tcp_transmit_skb net/ipv4/tcp_output.c:1047 [inline]
 [<ffffffff8243c54a>] __tcp_retransmit_skb+0x5ea/0x1710 net/ipv4/tcp_output.c:2665
 [<ffffffff8243de33>] tcp_retransmit_skb+0x23/0x2c0 net/ipv4/tcp_output.c:2682
 [<ffffffff8244394e>] tcp_retransmit_timer net/ipv4/tcp_timer.c:461 [inline]
 [<ffffffff8244394e>] tcp_retransmit_timer+0x7ee/0x1f70 net/ipv4/tcp_timer.c:379
 [<ffffffff8244548c>] tcp_write_timer_handler+0x3bc/0x700 net/ipv4/tcp_timer.c:543
 [<ffffffff8244588d>] tcp_write_timer+0xbd/0xd0 net/ipv4/tcp_timer.c:561
 [<ffffffff812582dd>] call_timer_fn+0x18d/0x850 kernel/time/timer.c:1185
 [<ffffffff81258ebf>] __run_timers kernel/time/timer.c:1261 [inline]
 [<ffffffff81258ebf>] run_timer_softirq+0x51f/0xb70 kernel/time/timer.c:1444
 [<ffffffff8271bb16>] __do_softirq+0x226/0xa3f kernel/softirq.c:273
 [<ffffffff810e1a8a>] invoke_softirq kernel/softirq.c:350 [inline]
 [<ffffffff810e1a8a>] irq_exit+0x10a/0x150 kernel/softirq.c:391
 [<ffffffff8271b24e>] exiting_irq arch/x86/include/asm/apic.h:652 [inline]
 [<ffffffff8271b24e>] smp_apic_timer_interrupt+0x7e/0xb0 arch/x86/kernel/apic/apic.c:926
 [<ffffffff8271a59d>] apic_timer_interrupt+0x9d/0xb0 arch/x86/entry/entry_64.S:768
 <EOI> 
 [<ffffffff8230eda8>] local_bh_enable include/linux/bottom_half.h:31 [inline]
 [<ffffffff8230eda8>] get_next_corpse net/netfilter/nf_conntrack_core.c:1403 [inline]
 [<ffffffff8230eda8>] nf_ct_iterate_cleanup+0x108/0x500 net/netfilter/nf_conntrack_core.c:1432
 [<ffffffff8232392c>] nf_ct_l4proto_pernet_unregister+0xac/0x110 net/netfilter/nf_conntrack_proto.c:473
 [<ffffffff823377ad>] sctp_net_exit+0x1d/0x30 net/netfilter/nf_conntrack_proto_sctp.c:932
 [<ffffffff82217d90>] ops_exit_list.isra.0+0xb0/0x160 net/core/net_namespace.c:134
 [<ffffffff8221ac16>] cleanup_net+0x3d6/0x860 net/core/net_namespace.c:452
 [<ffffffff81122c25>] process_one_work+0x825/0x1720 kernel/workqueue.c:2064
 [<ffffffff81124004>] worker_thread+0x4e4/0xf50 kernel/workqueue.c:2196
 [<ffffffff811342c3>] kthread+0x273/0x310 kernel/kthread.c:211
 [<ffffffff82718fc5>] ret_from_fork+0x55/0x80 arch/x86/entry/entry_64.S:537
Code: ff ff e8 4d 2b 11 ff be 8e 08 00 00 48 c7 c7 e0 25 a5 82 e8 cc cf ed fe e9 48 fe ff ff 44 8b 7d d4 e9 c4 fd ff ff e8 29 2b 11 ff <0f> 0b 4c 89 f7 e8 8f e3 28 ff e9 b2 fa ff ff 48 89 55 b8 e8 c1 
RIP  [<ffffffff821f6ac7>] skb_copy_and_csum_bits+0x6e7/0x800 net/core/skbuff.c:2208
 RSP <ffff8801db7072b8>
---[ end trace 506e320467e79c00 ]---