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 52b0b067 P4D 52b0b067 PUD 53d98067 PMD 0 
Oops: 0010 [#1] PREEMPT SMP KASAN
Modules linked in:
CPU: 1 PID: 7049 Comm: kworker/1:3 Not tainted 4.14.138 #34
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: pencrypt padata_serial_worker
task: ffff88807cacc300 task.stack: ffff88805d2c8000
RIP: 0010:          (null)
RSP: 0018:ffff88805d2cfc80 EFLAGS: 00010246
RAX: dffffc0000000000 RBX: ffff88808dfcddc0 RCX: ffff88805d2cfcf0
RDX: 1ffff11011bf9bba RSI: 0000000000000000 RDI: ffff88808dfcddc0
RBP: ffff88805d2cfc98 R08: ffff88807cacc300 R09: 0000000000000002
R10: 0000000000000000 R11: ffff88807cacc300 R12: ffff88805d2cfd10
R13: ffff88821943791c R14: ffff88808dfcde18 R15: ffff88808dfcde10
FS:  0000000000000000(0000) GS:ffff8880aef00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 0000000048bc5000 CR4: 00000000001426e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 aead_request_complete include/crypto/internal/aead.h:75 [inline]
 pcrypt_aead_serial+0x7e/0xb0 crypto/pcrypt.c:123
 padata_serial_worker+0x261/0x400 kernel/padata.c:312
 process_one_work+0x863/0x1600 kernel/workqueue.c:2114
 worker_thread+0x5d9/0x1050 kernel/workqueue.c:2248
 kthread+0x319/0x430 kernel/kthread.c:232
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404
Code:  Bad RIP value.
RIP:           (null) RSP: ffff88805d2cfc80
CR2: 0000000000000000
---[ end trace c745343b68f5c70d ]---