When GRO is off, the transport header pointer in sk_buff is
initialized to network's header.
To find the udp header, instead of using udp_hdr() which assumes
skb_network_header was set, manually calculate the udp header offset.
Fixes: 0952da791c97 ("net/mlx5e: Add support for loopback selftest")
Signed-off-by: Inbar Karmy <inbark@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
        if (iph->protocol != IPPROTO_UDP)
                goto out;
 
-       udph = udp_hdr(skb);
+       /* Don't assume skb_transport_header() was set */
+       udph = (struct udphdr *)((u8 *)iph + 4 * iph->ihl);
        if (udph->dest != htons(9))
                goto out;