nf_nat_ipv6_manip_pkt
if (nf_nat_ipv6_manip_pkt(skb, 0, &target, mtype))
if (!nf_nat_ipv6_manip_pkt(skb, hdrlen + sizeof(inside->icmp6),
if (!nf_nat_ipv6_manip_pkt(skb, 0, &target, manip))