IPv6: ADDRCONF(NETDEV_UP): veth0: link is not ready
IPv6: ADDRCONF(NETDEV_CHANGE): veth0: link becomes ready
hrtimer: interrupt took 54063 ns
l2tp_core: tunl 4: sockfd_lookup(fd=6) returned -9
l2tp_core: tunl 4: sockfd_lookup(fd=6) returned -9
BUG: unable to handle kernel NULL pointer dereference at 0000000000000080
IP: [<ffffffff835a93b8>] sock_hold include/net/sock.h:589 [inline]
IP: [<ffffffff835a93b8>] l2tp_session_create+0x948/0x1030 net/l2tp/l2tp_core.c:1809
PGD b2566067 PUD b3dab067 PMD 0 
Oops: 0002 [#1] PREEMPT SMP KASAN
Dumping ftrace buffer:
   (ftrace buffer empty)
Modules linked in:
CPU: 1 PID: 5365 Comm: syz-executor0 Not tainted 4.4.150-g5541782 #19
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8800af6e8000 task.stack: ffff8800af040000
RIP: 0010:[<ffffffff835a93b8>]  [<ffffffff835a93b8>] sock_hold include/net/sock.h:589 [inline]
RIP: 0010:[<ffffffff835a93b8>]  [<ffffffff835a93b8>] l2tp_session_create+0x948/0x1030 net/l2tp/l2tp_core.c:1809
RSP: 0018:ffff8800af047ad0  EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff8801d027a780 RCX: 0000000000000006
RDX: 1ffff1003a04f520 RSI: ffffffff835a3493 RDI: ffff8801d027a900
RBP: ffff8800af047b40 R08: ffff8800af6e8900 R09: 0000000000000000
R10: 0000000000000000 R11: ffffffff8463a140 R12: ffff8800b26ab9a8
R13: ffff8800af047c58 R14: ffff8800b26ab900 R15: ffffffff835a20c0
FS:  0000000000000000(0000) GS:ffff8801db300000(0063) knlGS:00000000f7769b40
CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 0000000000000080 CR3: 00000000ba553000 CR4: 00000000001606f0
Stack:
 ffffffff8114094a ffff8801d027a7a0 ffff8800b26aba58 ffff8800b26ab910
 ffffffff838caa10 ffff8800b26ab9b0 ffff8800b26aba50 ffff8801d027a860
 ffffffff00000000 ffff8801d94b6e80 0000000000000000 ffff8801d94b6eb0
Call Trace:
 [<ffffffff835ad7b0>] pppol2tp_connect+0x10f0/0x1910 net/l2tp/l2tp_ppp.c:725
 [<ffffffff82f266a8>] SYSC_connect+0x1b8/0x300 net/socket.c:1558
 [<ffffffff82f28fe4>] 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
 [<ffffffff838cca03>] 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  [<ffffffff835a93b8>] sock_hold include/net/sock.h:589 [inline]
RIP  [<ffffffff835a93b8>] l2tp_session_create+0x948/0x1030 net/l2tp/l2tp_core.c:1809
 RSP <ffff8800af047ad0>
CR2: 0000000000000080
---[ end trace 8cea79677cea6dc1 ]---