WARNING: CPU: 0 PID: 2994 at net/ipv6/ip6_fib.c:1137 fib6_add+0x20d9/0x2c10 net/ipv6/ip6_fib.c:1137
Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 2994 Comm: syzkaller781077 Not tainted 4.14.0-rc5-mm1+ #20
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:16 [inline]
 dump_stack+0x194/0x257 lib/dump_stack.c:52
 panic+0x1e4/0x41c kernel/panic.c:183
 __warn+0x1c4/0x1e0 kernel/panic.c:546
 report_bug+0x211/0x2d0 lib/bug.c:183
 fixup_bug+0x40/0x90 arch/x86/kernel/traps.c:177
 do_trap_no_signal arch/x86/kernel/traps.c:211 [inline]
 do_trap+0x260/0x390 arch/x86/kernel/traps.c:260
 do_error_trap+0x120/0x390 arch/x86/kernel/traps.c:297
 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:310
 invalid_op+0x18/0x20 arch/x86/entry/entry_64.S:905
RIP: 0010:fib6_add+0x20d9/0x2c10 net/ipv6/ip6_fib.c:1137
RSP: 0018:ffff8801d21a76a0 EFLAGS: 00010293
RAX: ffff8801d23725c0 RBX: 1ffff1003a434eec RCX: ffffffff8441b159
RDX: 0000000000000000 RSI: ffff8801c048d380 RDI: ffff8801c048d400
RBP: ffff8801d21a7a08 R08: 0000000000000000 R09: 0000000000000004
R10: ffff8801d21a78d0 R11: 0000000000000003 R12: 0000000000000001
R13: dffffc0000000000 R14: ffff8801c048d380 R15: ffffffff86027940
 __ip6_ins_rt+0x6c/0x90 net/ipv6/route.c:1001
 ip6_route_add+0x148/0x1a0 net/ipv6/route.c:2760
 ipv6_route_ioctl+0x4cf/0x690 net/ipv6/route.c:3269
 inet6_ioctl+0xef/0x1e0 net/ipv6/af_inet6.c:521
 sock_do_ioctl+0x65/0xb0 net/socket.c:960
 sock_ioctl+0x2c2/0x440 net/socket.c:1057
 vfs_ioctl fs/ioctl.c:45 [inline]
 do_vfs_ioctl+0x1b1/0x1520 fs/ioctl.c:685
 SYSC_ioctl fs/ioctl.c:700 [inline]
 SyS_ioctl+0x8f/0xc0 fs/ioctl.c:691
 entry_SYSCALL_64_fastpath+0x1f/0xbe
RIP: 0033:0x43ff59
RSP: 002b:00007ffc28b3f208 EFLAGS: 00000213 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 000000000043ff59
RDX: 00000000206bb000 RSI: 000000000000890b RDI: 0000000000000003
RBP: 0000000000000082 R08: 0000000000000000 R09: 00000000004018c0
R10: 0000000000000000 R11: 0000000000000213 R12: 00000000004018c0
R13: 0000000000401950 R14: 0000000000000000 R15: 0000000000000000
Dumping ftrace buffer:
   (ftrace buffer empty)
Kernel Offset: disabled
Rebooting in 86400 seconds..