TCP: request_sock_TCPv6: Possible SYN flooding on port 20002. Sending cookies. Check SNMP counters. TCP: request_sock_TCPv6: Possible SYN flooding on port 20002. Sending cookies. Check SNMP counters. TCP: request_sock_TCPv6: Possible SYN flooding on port 20002. Sending cookies. Check SNMP counters. TCP: request_sock_TCPv6: Possible SYN flooding on port 20002. Sending cookies. Check SNMP counters. WARNING: CPU: 0 PID: 5872 at include/net/sock.h:1539 sock_owned_by_me include/net/sock.h:1539 [inline] WARNING: CPU: 0 PID: 5872 at include/net/sock.h:1539 tcp_cleanup_ulp+0x1ad/0x200 net/ipv4/tcp_ulp.c:102 Kernel panic - not syncing: panic_on_warn set ... CPU: 0 PID: 5872 Comm: syz-executor0 Not tainted 4.19.0-rc8-next-20181016+ #95 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x244/0x39d lib/dump_stack.c:113 panic+0x2ad/0x55c kernel/panic.c:188 __warn.cold.8+0x20/0x45 kernel/panic.c:540 report_bug+0x254/0x2d0 lib/bug.c:186 fixup_bug arch/x86/kernel/traps.c:178 [inline] do_error_trap+0x11b/0x200 arch/x86/kernel/traps.c:271 do_invalid_op+0x36/0x40 arch/x86/kernel/traps.c:290 invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:969 RIP: 0010:sock_owned_by_me include/net/sock.h:1539 [inline] RIP: 0010:tcp_cleanup_ulp+0x1ad/0x200 net/ipv4/tcp_ulp.c:102 Code: 83 c0 03 38 d0 7c 04 84 d2 75 61 44 8b 25 cb 4e df 02 31 ff 44 89 e6 e8 51 3d ed fa 45 85 e4 0f 84 91 fe ff ff e8 33 3c ed fa <0f> 0b e9 85 fe ff ff 4c 89 ef e8 34 84 30 fb e9 9f fe ff ff 4c 89 RSP: 0018:ffff8801dae06860 EFLAGS: 00010206 RAX: ffff8801b933c480 RBX: ffff8801ce18cc80 RCX: ffffffff8690e6ff RDX: 0000000000000100 RSI: ffffffff8690e70d RDI: 0000000000000005 RBP: ffff8801dae06880 R08: ffff8801b933c480 R09: 0000000000000002 R10: 0000000000000000 R11: ffff8801b933c480 R12: 0000000000000001 R13: 0000000000000000 R14: 0000000000000003 R15: ffff8801dae069a0 tcp_v4_destroy_sock+0x15c/0x980 net/ipv4/tcp_ipv4.c:1980 tcp_v6_destroy_sock+0x15/0x20 net/ipv6/tcp_ipv6.c:1762 inet_csk_destroy_sock+0x19f/0x440 net/ipv4/inet_connection_sock.c:838 tcp_done+0x272/0x310 net/ipv4/tcp.c:3760 tcp_v6_syn_recv_sock+0x1f21/0x25f0 net/ipv6/tcp_ipv6.c:1236 tcp_get_cookie_sock+0x10e/0x580 net/ipv4/syncookies.c:213 cookie_v6_check+0x1830/0x27d0 net/ipv6/syncookies.c:257 tcp_v6_cookie_check net/ipv6/tcp_ipv6.c:1028 [inline] tcp_v6_do_rcv+0x10ea/0x13c0 net/ipv6/tcp_ipv6.c:1336 tcp_v6_rcv+0x34e0/0x3ab0 net/ipv6/tcp_ipv6.c:1545 ip6_input_finish+0x3fc/0x1aa0 net/ipv6/ip6_input.c:384 NF_HOOK include/linux/netfilter.h:289 [inline] ip6_input+0xe4/0x600 net/ipv6/ip6_input.c:427 dst_input include/net/dst.h:450 [inline] ip6_rcv_finish+0x17a/0x330 net/ipv6/ip6_input.c:76 NF_HOOK include/linux/netfilter.h:289 [inline] ipv6_rcv+0x110/0x630 net/ipv6/ip6_input.c:272 __netif_receive_skb_one_core+0x14d/0x200 net/core/dev.c:4930 __netif_receive_skb+0x27/0x1e0 net/core/dev.c:5040 process_backlog+0x24e/0x7a0 net/core/dev.c:5844 napi_poll net/core/dev.c:6264 [inline] net_rx_action+0x7fa/0x19b0 net/core/dev.c:6330 __do_softirq+0x308/0xb7e kernel/softirq.c:292 do_softirq_own_stack+0x2a/0x40 arch/x86/entry/entry_64.S:1023 do_softirq.part.14+0x126/0x160 kernel/softirq.c:337 do_softirq kernel/softirq.c:329 [inline] __local_bh_enable_ip+0x21d/0x260 kernel/softirq.c:189 local_bh_enable include/linux/bottom_half.h:32 [inline] rcu_read_unlock_bh include/linux/rcupdate.h:696 [inline] ip6_finish_output2+0xce4/0x27a0 net/ipv6/ip6_output.c:121 ip6_finish_output+0x468/0xc60 net/ipv6/ip6_output.c:154 NF_HOOK_COND include/linux/netfilter.h:278 [inline] ip6_output+0x232/0x9d0 net/ipv6/ip6_output.c:171 dst_output include/net/dst.h:444 [inline] NF_HOOK include/linux/netfilter.h:289 [inline] ip6_xmit+0xf64/0x2410 net/ipv6/ip6_output.c:275 inet6_csk_xmit+0x375/0x630 net/ipv6/inet6_connection_sock.c:139 __tcp_transmit_skb+0x1bc5/0x3b00 net/ipv4/tcp_output.c:1162 tcp_transmit_skb net/ipv4/tcp_output.c:1178 [inline] tcp_write_xmit+0x1676/0x5710 net/ipv4/tcp_output.c:2364 tcp_push_one+0xdd/0x110 net/ipv4/tcp_output.c:2551 tcp_sendmsg_locked+0xbc3/0x3fa0 net/ipv4/tcp.c:1386 tcp_sendmsg+0x2f/0x50 net/ipv4/tcp.c:1443 inet_sendmsg+0x19c/0x690 net/ipv4/af_inet.c:798 sock_sendmsg_nosec net/socket.c:622 [inline] sock_sendmsg+0xd5/0x120 net/socket.c:632 __sys_sendto+0x3d7/0x670 net/socket.c:1789 __do_sys_sendto net/socket.c:1801 [inline] __se_sys_sendto net/socket.c:1797 [inline] __x64_sys_sendto+0xe1/0x1a0 net/socket.c:1797 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457569 Code: fd b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 cb b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fa9f39e1c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 0000000000457569 RDX: fffffffffffffedd RSI: 0000000020000280 RDI: 0000000000000008 RBP: 000000000072c040 R08: 0000000020000080 R09: 000000000000001c R10: 0000000020000004 R11: 0000000000000246 R12: 00007fa9f39e26d4 R13: 00000000004c3921 R14: 00000000004d57d8 R15: 00000000ffffffff Kernel Offset: disabled Rebooting in 86400 seconds..