TCP: request_sock_TCP: 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 accessgeneral protection fault: 0000 [#1] PREEMPT SMP KASAN
Dumping ftrace buffer:
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Modules linked in:
CPU: 1 PID: 6526 Comm: syz-executor7 Not tainted 4.4.125-g38f41ec #63
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8801d25b9800 task.stack: ffff8800b56e8000
RIP: 0010:[<ffffffff83468b00>]  [<ffffffff83468b00>] __read_once_size include/linux/compiler.h:218 [inline]
RIP: 0010:[<ffffffff83468b00>]  [<ffffffff83468b00>] sk_dst_get include/net/sock.h:1740 [inline]
RIP: 0010:[<ffffffff83468b00>]  [<ffffffff83468b00>] pppol2tp_connect+0x7e0/0x1930 net/l2tp/l2tp_ppp.c:755
RSP: 0018:ffff8800b56efbc8  EFLAGS: 00010202
RAX: dffffc0000000000 RBX: ffff8801ce6f4000 RCX: ffffffff83468ae8
RDX: 000000000000003b RSI: ffffc90004d19000 RDI: 00000000000001d8
RBP: ffff8800b56efd78 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 1ffff10016addf44 R12: ffff8800b40e4c80
R13: 0000000000000000 R14: 000000000000197e R15: 1ffff10016addf82
FS:  00007f7a872fc700(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f145335e6f0 CR3: 00000000bb37a000 CR4: 0000000000160670
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:
 ffffffff83468a89 00000018d2cde930 ffff880000000003 ffff8801ce6f4198
 ffff8801ce6f4900 ffff8800b40e5050 ffff8800b40e4c92 ffff8800b40e4cb0
 ffff8801ce6f4780 0000000041b58ab3 ffffffff84011a60 ffffffff83468320
Call Trace:
 [<ffffffff82df21b6>] SYSC_connect+0x1b6/0x310 net/socket.c:1557
 [<ffffffff82df4a24>] SyS_connect+0x24/0x30 net/socket.c:1538
 [<ffffffff83779965>] entry_SYSCALL_64_fastpath+0x22/0x9e
Code: fd 80 3d 69 3d 37 01 00 0f 84 ca 08 00 00 e8 98 8b ef fd 49 8d bd d8 01 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 60 0d 00 00 4d 8b b5 d8 01 00 00 e8 aa d8 e1 
RIP  [<ffffffff83468b00>] __read_once_size include/linux/compiler.h:218 [inline]
RIP  [<ffffffff83468b00>] sk_dst_get include/net/sock.h:1740 [inline]
RIP  [<ffffffff83468b00>] pppol2tp_connect+0x7e0/0x1930 net/l2tp/l2tp_ppp.c:755
 RSP <ffff8800b56efbc8>
---[ end trace bba45dfabe332159 ]---
Kernel panic - not syncing: Fatal exception
Dumping ftrace buffer:
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Kernel Offset: disabled
Rebooting in 86400 seconds..