TCP: request_sock_TCPv6: Possible SYN flooding on port 20002. Sending cookies.  Check SNMP counters.
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
Modules linked in:
CPU: 1 PID: 14651 Comm: syz-executor.2 Not tainted 4.14.143 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff888093966300 task.stack: ffff88805c360000
RIP: 0010:tcp_mark_push net/ipv4/tcp.c:630 [inline]
RIP: 0010:tcp_push+0xe9/0x610 net/ipv4/tcp.c:694
RSP: 0018:ffff88805c367a48 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffc9000d86a000
RDX: 0000000000000007 RSI: ffffffff85231b30 RDI: 0000000000000038
RBP: ffff88805c367a98 R08: ffff88805e91695c R09: ffff888093966ba0
R10: 0000000000000000 R11: 0000000000000000 R12: ffff88805e9160c0
R13: 0000000000000000 R14: ffff88805e916954 R15: 0000000000000000
FS:  00007f4deac2e700(0000) GS:ffff8880aef00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000021000000 CR3: 0000000088dd4000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 tcp_sendmsg_locked+0x2307/0x3200 net/ipv4/tcp.c:1426
 tcp_sendmsg+0x30/0x50 net/ipv4/tcp.c:1457
 inet_sendmsg+0x122/0x500 net/ipv4/af_inet.c:762
 sock_sendmsg_nosec net/socket.c:646 [inline]
 sock_sendmsg+0xce/0x110 net/socket.c:656
 SYSC_sendto+0x206/0x310 net/socket.c:1763
 SyS_sendto+0x40/0x50 net/socket.c:1731
 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x4598e9
RSP: 002b:00007f4deac2dc78 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 00000000004598e9
RDX: 00000000fffffdda RSI: 00000000200000c0 RDI: 000000000000000a
RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f4deac2e6d4
R13: 00000000004c7880 R14: 00000000004dd188 R15: 00000000ffffffff
Code: 00 4d 8d 84 24 9c 08 00 00 4c 89 45 b8 e8 40 c7 39 fc 48 8d 7b 38 4c 8b 45 b8 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <0f> b6 04 02 84 c0 74 06 0f 8e 1e 04 00 00 48 b8 00 00 00 00 00 
RIP: tcp_mark_push net/ipv4/tcp.c:630 [inline] RSP: ffff88805c367a48
RIP: tcp_push+0xe9/0x610 net/ipv4/tcp.c:694 RSP: ffff88805c367a48
---[ end trace 9d46a7c4b4666bc6 ]---