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: 12993 Comm: syz-executor.1 Not tainted 4.14.145 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff888067546280 task.stack: ffff888066cb0000
RIP: 0010:tcp_sendmsg_locked+0x50e/0x3200 net/ipv4/tcp.c:1281
RSP: 0018:ffff888066cb7aa8 EFLAGS: 00010206
RAX: 0000000000000012 RBX: 0000000000000000 RCX: ffffc90008036000
RDX: 0000000000000118 RSI: ffffffff85240e44 RDI: 0000000000000090
RBP: ffff888066cb7c40 R08: ffff888067546280 R09: 0000000000000001
R10: 0000000000000000 R11: ffff888067546280 R12: dffffc0000000000
R13: ffff8880a9756c80 R14: ffff888066cb7d60 R15: ffff8880596e8380
FS:  00007fe73e51c700(0000) GS:ffff8880aef00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b32f25000 CR3: 0000000072b74000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 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: 0033:0x459a09
RSP: 002b:00007fe73e51bc78 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 0000000000459a09
RDX: ffffffffffffffc1 RSI: 0000000020000080 RDI: 0000000000000004
RBP: 000000000075bf20 R08: 0000000000000000 R09: fffffffffffffe5b
R10: 0000000000000040 R11: 0000000000000246 R12: 00007fe73e51c6d4
R13: 00000000004c79b8 R14: 00000000004dd418 R15: 00000000ffffffff
Code: d4 38 fc 4d 85 ed 0f 84 40 08 00 00 e8 ac d4 38 fc 8b 85 78 ff ff ff 48 8d bb 90 00 00 00 89 85 50 ff ff ff 48 89 f8 48 c1 e8 03 <42> 0f b6 04 20 84 c0 74 06 0f 8e 4a 25 00 00 f6 83 90 00 00 00 
RIP: tcp_sendmsg_locked+0x50e/0x3200 net/ipv4/tcp.c:1281 RSP: ffff888066cb7aa8
---[ end trace c889cc9ad745d360 ]---