payload_len is a be16 value, not cpu_endian, also the size of a ponter
to a struct ipv6hdr was being added, not the size of the struct itself.
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
        iph                     =       ipv6_hdr(skb);
        iph->version            =       6;
        iph->nexthdr            =       IPPROTO_IPV6;
-       iph->payload_len        =       old_iph->payload_len + sizeof(old_iph);
+       iph->payload_len        =       old_iph->payload_len;
+       be16_add_cpu(&iph->payload_len, sizeof(*old_iph));
        iph->priority           =       old_iph->priority;
        memset(&iph->flow_lbl, 0, sizeof(iph->flow_lbl));
        iph->daddr              =       rt->rt6i_dst.addr;