tcp: Call skb_gro_checksum_validate

In tcp[64]_gro_receive call skb_gro_checksum_validate to validate TCP
checksum in the gro context.
Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv4/tcp_offload.c

@@ -288,35 +288,14 @@ static int tcp_v4_gso_send_check(struct sk_buff *skb)
 
 static struct sk_buff **tcp4_gro_receive(struct sk_buff **head, struct sk_buff *skb)
 {
-	/* Use the IP hdr immediately proceeding for this transport */
-	const struct iphdr *iph = skb_gro_network_header(skb);
-	__wsum wsum;
-
 	/* Don't bother verifying checksum if we're going to flush anyway. */
-	if (NAPI_GRO_CB(skb)->flush)
-		goto skip_csum;
-
-	wsum = NAPI_GRO_CB(skb)->csum;
-
-	switch (skb->ip_summed) {
-	case CHECKSUM_NONE:
-		wsum = skb_checksum(skb, skb_gro_offset(skb), skb_gro_len(skb),
-				    0);
-
-		/* fall through */
-
-	case CHECKSUM_COMPLETE:
-		if (!tcp_v4_check(skb_gro_len(skb), iph->saddr, iph->daddr,
-				  wsum)) {
-			skb->ip_summed = CHECKSUM_UNNECESSARY;
-			break;
-		}
-
+	if (!NAPI_GRO_CB(skb)->flush &&
+	    skb_gro_checksum_validate(skb, IPPROTO_TCP,
+				      inet_gro_compute_pseudo)) {
 		NAPI_GRO_CB(skb)->flush = 1;
 		return NULL;
 	}
 
-skip_csum:
 	return tcp_gro_receive(head, skb);
 }
 

net/ipv6/tcpv6_offload.c

@@ -35,34 +35,14 @@ static int tcp_v6_gso_send_check(struct sk_buff *skb)
 static struct sk_buff **tcp6_gro_receive(struct sk_buff **head,
 					 struct sk_buff *skb)
 {
-	const struct ipv6hdr *iph = skb_gro_network_header(skb);
-	__wsum wsum;
-
 	/* Don't bother verifying checksum if we're going to flush anyway. */
-	if (NAPI_GRO_CB(skb)->flush)
-		goto skip_csum;
-
-	wsum = NAPI_GRO_CB(skb)->csum;
-
-	switch (skb->ip_summed) {
-	case CHECKSUM_NONE:
-		wsum = skb_checksum(skb, skb_gro_offset(skb), skb_gro_len(skb),
-				    wsum);
-
-		/* fall through */
-
-	case CHECKSUM_COMPLETE:
-		if (!tcp_v6_check(skb_gro_len(skb), &iph->saddr, &iph->daddr,
-				  wsum)) {
-			skb->ip_summed = CHECKSUM_UNNECESSARY;
-			break;
-		}
-
+	if (!NAPI_GRO_CB(skb)->flush &&
+	    skb_gro_checksum_validate(skb, IPPROTO_TCP,
+				      ip6_gro_compute_pseudo)) {
 		NAPI_GRO_CB(skb)->flush = 1;
 		return NULL;
 	}
 
-skip_csum:
 	return tcp_gro_receive(head, skb);
 }