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: 3 PID: 8810 Comm: syz-executor3 Not tainted 4.13.0-rc5-next-20170817+ #5
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
task: ffff88003bea2840 task.stack: ffff880039630000
RIP: 0010:__ipv6_prefix_equal64_half include/net/ipv6.h:486 [inline]
RIP: 0010:ipv6_prefix_equal include/net/ipv6.h:503 [inline]
RIP: 0010:fib6_add_1 net/ipv6/ip6_fib.c:590 [inline]
RIP: 0010:fib6_add+0x6f8/0x33e0 net/ipv6/ip6_fib.c:1086
RSP: 0018:ffff880039636f88 EFLAGS: 00010202
RAX: 0000000000000020 RBX: 0000000000000008 RCX: ffffc90002e00000
RDX: 0000000000000b1e RSI: ffffffff842f9d3a RDI: 0000000000000100
RBP: ffff8800396371a8 R08: ffff8800396377a0 R09: 0000000000000000
R10: ffff880039637070 R11: ffff88003cdfdeb0 R12: dffffc0000000000
R13: 0000000000000000 R14: ffff88003c282f40 R15: 0000000000000000
FS:  00007f0d88001700(0000) GS:ffff88006df00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000430160 CR3: 0000000068346000 CR4: 00000000000006e0
Call Trace:
 __ip6_ins_rt+0x6c/0x90 net/ipv6/route.c:945
 ip6_route_add+0x148/0x1a0 net/ipv6/route.c:2111
 inet6_rtm_newroute+0x139/0x150 net/ipv6/route.c:3283
 rtnetlink_rcv_msg+0x733/0x1090 net/core/rtnetlink.c:4246
 netlink_rcv_skb+0x216/0x440 net/netlink/af_netlink.c:2397
 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:4258
 netlink_unicast_kernel net/netlink/af_netlink.c:1265 [inline]
 netlink_unicast+0x4e8/0x6f0 net/netlink/af_netlink.c:1291
 netlink_sendmsg+0xa4a/0xe60 net/netlink/af_netlink.c:1854
 sock_sendmsg_nosec net/socket.c:633 [inline]
 sock_sendmsg+0xca/0x110 net/socket.c:643
 sock_write_iter+0x31a/0x5d0 net/socket.c:912
 call_write_iter include/linux/fs.h:1743 [inline]
 do_iter_readv_writev+0x525/0x7f0 fs/read_write.c:650
 do_iter_write+0x154/0x540 fs/read_write.c:929
 vfs_writev+0x18a/0x340 fs/read_write.c:975
 do_writev+0xfc/0x2a0 fs/read_write.c:1011
 SYSC_writev fs/read_write.c:1084 [inline]
 SyS_writev+0x27/0x30 fs/read_write.c:1081
 entry_SYSCALL_64_fastpath+0x1f/0xbe
RIP: 0033:0x446739
RSP: 002b:00007f0d88000c08 EFLAGS: 00000296 ORIG_RAX: 0000000000000014
RAX: ffffffffffffffda RBX: 0000000000000017 RCX: 0000000000446739
RDX: 0000000000000001 RSI: 0000000020bad000 RDI: 0000000000000017
RBP: 0000000000a5f870 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000296 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f0d880019c0 R15: 00007f0d88001700
Code: c8 24 00 00 49 89 1e 49 89 de e9 f0 02 00 00 e8 bf 9f 3d fd 85 db 74 66 e8 b6 9f 3d fd 49 8d bd 00 01 00 00 48 89 f8 48 c1 e8 03 <42> 80 3c 20 00 0f 85 0d 2b 00 00 48 8b 85 60 fe ff ff 49 8b 95 
RIP: __ipv6_prefix_equal64_half include/net/ipv6.h:486 [inline] RSP: ffff880039636f88
RIP: ipv6_prefix_equal include/net/ipv6.h:503 [inline] RSP: ffff880039636f88
RIP: fib6_add_1 net/ipv6/ip6_fib.c:590 [inline] RSP: ffff880039636f88
RIP: fib6_add+0x6f8/0x33e0 net/ipv6/ip6_fib.c:1086 RSP: ffff880039636f88
---[ end trace 5cc5abda523242c4 ]---