TCP: request_sock_TCPv6: Possible SYN flooding on port 20002. Sending cookies.  Check SNMP counters.
BUG: unable to handle kernel NULL pointer dereference at           (null)
IP:           (null)
PGD 48d18067 P4D 48d18067 PUD 48d19067 PMD 0 
Oops: 0010 [#1] PREEMPT SMP KASAN
Modules linked in:
CPU: 1 PID: 10186 Comm: kworker/1:4 Not tainted 4.14.230-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: pencrypt padata_serial_worker
task: ffff88803c260040 task.stack: ffff88823a488000
RIP: 0010:          (null)
RSP: 0018:ffff88823a48fcd0 EFLAGS: 00010296
RAX: 0000000000000000 RBX: ffff88809beecd10 RCX: 1ffff11047491fa2
RDX: 1ffff110137dd99a RSI: 0000000000000000 RDI: ffff88809beeccc0
RBP: dffffc0000000000 R08: ffffe8ffffd24360 R09: 0000000000000002
R10: 0000000000000000 R11: ffff88803c260040 R12: 0000000000000001
R13: ffff88823a48fd10 R14: ffff888238842b00 R15: ffff88809beecd18
FS:  0000000000000000(0000) GS:ffff8880ba500000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 0000000048d17000 CR4: 00000000001426e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 padata_serial_worker+0x232/0x3e0 kernel/padata.c:307
 process_one_work+0x793/0x14a0 kernel/workqueue.c:2116
 worker_thread+0x5cc/0xff0 kernel/workqueue.c:2250
 kthread+0x30d/0x420 kernel/kthread.c:232
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404
Code:  Bad RIP value.
RIP:           (null) RSP: ffff88823a48fcd0
CR2: 0000000000000000
---[ end trace f688d28aa8a3600b ]---