kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] SMP KASAN
Dumping ftrace buffer:
   (ftrace buffer empty)
Modules linked in:
CPU: 0 PID: 8469 Comm: syz-executor4 Not tainted 4.16.0-rc4+ #264
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:ip6_xmit+0xc42/0x2260 net/ipv6/ip6_output.c:264
RSP: 0018:ffff8801d8fe75a8 EFLAGS: 00010246
RAX: dffffc0000000000 RBX: ffff8801b7615040 RCX: ffffffff84ef50c6
RDX: ffff8801b76150c0 RSI: ffffc90002939000 RDI: ffffffff81a93403
RBP: ffff8801d8fe7818 R08: 1ffff10036ec2a01 R09: ffff8801d8fe7768
R10: ffff8801d8fe75a8 R11: ffffed003b1fcef4 R12: 48ffffff66e8e689
R13: ffffed003b1fceed R14: 0000000000000040 R15: ffff8801b3dd88a4
FS:  00007fcc571c9700(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b9bc22000 CR3: 00000001cf713001 CR4: 00000000001606f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 inet6_csk_xmit+0x2fc/0x580 net/ipv6/inet6_connection_sock.c:139
 l2tp_xmit_core net/l2tp/l2tp_core.c:1053 [inline]
 l2tp_xmit_skb+0x105f/0x1410 net/l2tp/l2tp_core.c:1148
 pppol2tp_sendmsg+0x470/0x670 net/l2tp/l2tp_ppp.c:341
 sock_sendmsg_nosec net/socket.c:629 [inline]
 sock_sendmsg+0xca/0x110 net/socket.c:639
 SYSC_sendto+0x361/0x5c0 net/socket.c:1748
 SyS_sendto+0x40/0x50 net/socket.c:1716
 do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x453e69
RSP: 002b:00007fcc571c8c68 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007fcc571c96d4 RCX: 0000000000453e69
RDX: 000000000000100b RSI: 0000000020001180 RDI: 0000000000000014
RBP: 000000000072bea0 R08: 00000000200021c0 R09: 0000000000000080
R10: 0000000000040001 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000000004ca R14: 00000000006f7390 R15: 0000000000000000
Code: df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 52 13 00 00 48 8b 95 e0 fd ff ff 48 b8 00 00 00 00 00 fc ff df 4d 8b a4 24 d0 02 00 00 <65> 49 ff 44 24 28 48 c1 ea 03 0f b6 04 02 84 c0 74 08 3c 03 0f 
RIP: ip6_xmit+0xc42/0x2260 net/ipv6/ip6_output.c:264 RSP: ffff8801d8fe75a8
---[ end trace 2fb9926265201ba7 ]---
Kernel panic - not syncing: Fatal exception in interrupt
Dumping ftrace buffer:
   (ftrace buffer empty)
Kernel Offset: disabled
Rebooting in 86400 seconds..