4.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Inbar Karmy <inbark@xxxxxxxxxxxx> [ Upstream commit ef7a3518f7dd4f4cf5e5b5358c93d1eb78df28fb ] 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@xxxxxxxxxxxx> Signed-off-by: Saeed Mahameed <saeedm@xxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/net/ethernet/mellanox/mlx5/core/en_selftest.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/drivers/net/ethernet/mellanox/mlx5/core/en_selftest.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_selftest.c @@ -216,7 +216,8 @@ mlx5e_test_loopback_validate(struct sk_b 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;