IPVS: Schedule: port zero only supported in persistent services, check your ipvs configuration
BUG: unable to handle kernel NULL pointer dereference at 0000000000000080
IP: [<ffffffff835a6f58>] sock_hold include/net/sock.h:589 [inline]
IP: [<ffffffff835a6f58>] l2tp_session_create+0x948/0x1030 net/l2tp/l2tp_core.c:1809
PGD 1d459d067 PUD 1b727a067 PMD 0 
Oops: 0002 [#1] PREEMPT SMP KASAN
Dumping ftrace buffer:
   (ftrace buffer empty)
Modules linked in:
CPU: 0 PID: 14111 Comm: syz-executor5 Not tainted 4.4.147-ga5fc665 #16
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8801d058b000 task.stack: ffff8801bd8e8000
RIP: 0010:[<ffffffff835a6f58>]  [<ffffffff835a6f58>] sock_hold include/net/sock.h:589 [inline]
RIP: 0010:[<ffffffff835a6f58>]  [<ffffffff835a6f58>] l2tp_session_create+0x948/0x1030 net/l2tp/l2tp_core.c:1809
RSP: 0018:ffff8801bd8efad0  EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff8801a75f9b80 RCX: ffffc90008dc3000
RDX: 1ffff10034ebf3a0 RSI: ffffffff835a1033 RDI: ffff8801a75f9d00
RBP: ffff8801bd8efb40 R08: ffff8801d058b900 R09: 0000000000000000
R10: 0000000000000000 R11: ffffffff8463a1e0 R12: ffff8800a46145a8
R13: ffff8801bd8efc58 R14: ffff8800a4614500 R15: ffffffff8359fc60
FS:  0000000000000000(0000) GS:ffff8801db200000(0063) knlGS:00000000f576ab40
CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 0000000000000080 CR3: 00000001d1895000 CR4: 00000000001606f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:
 ffffffff8113fc2a ffff8801a75f9ba0 ffff8800a4614658 ffff8800a4614510
 ffffffff838c85b0 ffff8800a46145b0 ffff8800a4614650 ffff8801a75f9c60
 ffffffff00000000 ffff8800b2809100 0000000000000000 ffff8800b2809130
Call Trace:
 [<ffffffff835ab350>] pppol2tp_connect+0x10f0/0x1910 net/l2tp/l2tp_ppp.c:725
 [<ffffffff82f24298>] SYSC_connect+0x1b8/0x300 net/socket.c:1558
 [<ffffffff82f26bd4>] SyS_connect+0x24/0x30 net/socket.c:1539
 [<ffffffff81006d94>] do_syscall_32_irqs_on arch/x86/entry/common.c:393 [inline]
 [<ffffffff81006d94>] do_fast_syscall_32+0x324/0x8b0 arch/x86/entry/common.c:460
 [<ffffffff838ca5c3>] sysenter_flags_fixed+0xd/0x1a
Code: 00 00 48 8d bb 80 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 36 06 00 00 48 8b 83 80 01 00 00 <f0> ff 80 80 00 00 00 48 8d 43 20 48 89 c7 48 89 45 b0 e8 f1 13 
RIP  [<ffffffff835a6f58>] sock_hold include/net/sock.h:589 [inline]
RIP  [<ffffffff835a6f58>] l2tp_session_create+0x948/0x1030 net/l2tp/l2tp_core.c:1809
 RSP <ffff8801bd8efad0>
CR2: 0000000000000080
---[ end trace e441de87b70bb359 ]---