TCP: request_sock_TCPv6: Possible SYN flooding on port 20002. Sending cookies.  Check SNMP counters.
WARNING: CPU: 1 PID: 3649 at net/core/stream.c:206 sk_stream_kill_queues+0x3c5/0x520 net/core/stream.c:206
Kernel panic - not syncing: panic_on_warn set ...

CPU: 1 PID: 3649 Comm: syzkaller674384 Not tainted 4.15.0-rc8+ #173
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x194/0x257 lib/dump_stack.c:53
 panic+0x1e4/0x41c kernel/panic.c:183
 __warn+0x1dc/0x200 kernel/panic.c:547
 report_bug+0x211/0x2d0 lib/bug.c:184
 fixup_bug.part.11+0x37/0x80 arch/x86/kernel/traps.c:178
 fixup_bug arch/x86/kernel/traps.c:247 [inline]
 do_error_trap+0x2d7/0x3e0 arch/x86/kernel/traps.c:296
 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:315
 invalid_op+0x22/0x40 arch/x86/entry/entry_64.S:1085
RIP: 0010:sk_stream_kill_queues+0x3c5/0x520 net/core/stream.c:206
RSP: 0018:ffff8801d900f448 EFLAGS: 00010293
RAX: ffff8801bb5ea280 RBX: ffff8801bdb30040 RCX: ffffffff84340ec5
RDX: 0000000000000000 RSI: 1ffff1003b201e70 RDI: ffff8801bdb30278
RBP: ffff8801d900f488 R08: 1ffff1003b201e02 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000b00
R13: ffff8801bdb30230 R14: ffffffff888c3180 R15: ffff8801bdb30178
 inet_csk_destroy_sock+0x175/0x3f0 net/ipv4/inet_connection_sock.c:834
 tcp_close+0x8ad/0xfc0 net/ipv4/tcp.c:2312
 tls_sk_proto_close+0x4f8/0x800 net/tls/tls_main.c:260
 inet_release+0xed/0x1c0 net/ipv4/af_inet.c:426
 inet6_release+0x50/0x70 net/ipv6/af_inet6.c:432
 sock_release+0x8d/0x1e0 net/socket.c:602
 sock_close+0x16/0x20 net/socket.c:1131
 __fput+0x327/0x7e0 fs/file_table.c:210
 ____fput+0x15/0x20 fs/file_table.c:244
 task_work_run+0x199/0x270 kernel/task_work.c:113
 exit_task_work include/linux/task_work.h:22 [inline]
 do_exit+0x9bb/0x1ad0 kernel/exit.c:865
 do_group_exit+0x149/0x400 kernel/exit.c:968
 SYSC_exit_group kernel/exit.c:979 [inline]
 SyS_exit_group+0x1d/0x20 kernel/exit.c:977
 do_syscall_32_irqs_on arch/x86/entry/common.c:327 [inline]
 do_fast_syscall_32+0x3ee/0xf9d arch/x86/entry/common.c:389
 entry_SYSENTER_compat+0x54/0x63 arch/x86/entry/entry_64_compat.S:129
RIP: 0023:0xf7fc1c79
RSP: 002b:00000000ffeae5dc EFLAGS: 00000292 ORIG_RAX: 00000000000000fc
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00000000080eb298
RDX: 0000000000000000 RSI: 00000000080d5cf8 RDI: 00000000080eb2a0
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
Dumping ftrace buffer:
   (ftrace buffer empty)
Kernel Offset: disabled
Rebooting in 86400 seconds..