gso: Remove arbitrary checks for unsupported GSO

In several gso_segment functions there are checks of gso_type against
a seemingly arbitrary list of SKB_GSO_* flags. This seems like an
attempt to identify unsupported GSO types, but since the stack is
the one that set these GSO types in the first place this seems
unnecessary to do. If a combination isn't valid in the first
place that stack should not allow setting it.

This is a code simplication especially for add new GSO types.

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

7 files changed, 1 insertions, 102 deletions

diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c
index 2e6e65f..7f08d45 100644
--- a/net/ipv4/af_inet.c
+++ b/net/ipv4/af_inet.c
@@ -1205,24 +1205,6 @@ static struct sk_buff *inet_gso_segment(struct sk_buff *skb,
 	int ihl;
 	int id;
 
-	if (unlikely(skb_shinfo(skb)->gso_type &
-		     ~(SKB_GSO_TCPV4 |
-		       SKB_GSO_UDP |
-		       SKB_GSO_DODGY |
-		       SKB_GSO_TCP_ECN |
-		       SKB_GSO_GRE |
-		       SKB_GSO_GRE_CSUM |
-		       SKB_GSO_IPIP |
-		       SKB_GSO_SIT |
-		       SKB_GSO_TCPV6 |
-		       SKB_GSO_UDP_TUNNEL |
-		       SKB_GSO_UDP_TUNNEL_CSUM |
-		       SKB_GSO_TCP_FIXEDID |
-		       SKB_GSO_TUNNEL_REMCSUM |
-		       SKB_GSO_PARTIAL |
-		       0)))
-		goto out;
-
 	skb_reset_network_header(skb);
 	nhoff = skb_network_header(skb) - skb_mac_header(skb);
 	if (unlikely(!pskb_may_pull(skb, sizeof(*iph))))
diff --git a/net/ipv4/gre_offload.c b/net/ipv4/gre_offload.c
index e88190a..ecd1e09 100644
--- a/net/ipv4/gre_offload.c
+++ b/net/ipv4/gre_offload.c
@@ -26,20 +26,6 @@ static struct sk_buff *gre_gso_segment(struct sk_buff *skb,
 	int gre_offset, outer_hlen;
 	bool need_csum, ufo;
 
-	if (unlikely(skb_shinfo(skb)->gso_type &
-				~(SKB_GSO_TCPV4 |
-				  SKB_GSO_TCPV6 |
-				  SKB_GSO_UDP |
-				  SKB_GSO_DODGY |
-				  SKB_GSO_TCP_ECN |
-				  SKB_GSO_TCP_FIXEDID |
-				  SKB_GSO_GRE |
-				  SKB_GSO_GRE_CSUM |
-				  SKB_GSO_IPIP |
-				  SKB_GSO_SIT |
-				  SKB_GSO_PARTIAL)))
-		goto out;
-
 	if (!skb->encapsulation)
 		goto out;
 
diff --git a/net/ipv4/tcp_offload.c b/net/ipv4/tcp_offload.c
index 02737b6..5c59649 100644
--- a/net/ipv4/tcp_offload.c
+++ b/net/ipv4/tcp_offload.c
@@ -83,25 +83,6 @@ struct sk_buff *tcp_gso_segment(struct sk_buff *skb,
 
 	if (skb_gso_ok(skb, features | NETIF_F_GSO_ROBUST)) {
 		/* Packet is from an untrusted source, reset gso_segs. */
-		int type = skb_shinfo(skb)->gso_type;
-
-		if (unlikely(type &
-			     ~(SKB_GSO_TCPV4 |
-			       SKB_GSO_DODGY |
-			       SKB_GSO_TCP_ECN |
-			       SKB_GSO_TCP_FIXEDID |
-			       SKB_GSO_TCPV6 |
-			       SKB_GSO_GRE |
-			       SKB_GSO_GRE_CSUM |
-			       SKB_GSO_IPIP |
-			       SKB_GSO_SIT |
-			       SKB_GSO_UDP_TUNNEL |
-			       SKB_GSO_UDP_TUNNEL_CSUM |
-			       SKB_GSO_TUNNEL_REMCSUM |
-			       0) ||
-			     !(type & (SKB_GSO_TCPV4 |
-				       SKB_GSO_TCPV6))))
-			goto out;
 
 		skb_shinfo(skb)->gso_segs = DIV_ROUND_UP(skb->len, mss);
 
diff --git a/net/ipv4/udp_offload.c b/net/ipv4/udp_offload.c
index 6b7459c..81f253b 100644
--- a/net/ipv4/udp_offload.c
+++ b/net/ipv4/udp_offload.c
@@ -209,16 +209,6 @@ static struct sk_buff *udp4_ufo_fragment(struct sk_buff *skb,
 
 	if (skb_gso_ok(skb, features | NETIF_F_GSO_ROBUST)) {
 		/* Packet is from an untrusted source, reset gso_segs. */
-		int type = skb_shinfo(skb)->gso_type;
-
-		if (unlikely(type & ~(SKB_GSO_UDP | SKB_GSO_DODGY |
-				      SKB_GSO_UDP_TUNNEL |
-				      SKB_GSO_UDP_TUNNEL_CSUM |
-				      SKB_GSO_TUNNEL_REMCSUM |
-				      SKB_GSO_IPIP |
-				      SKB_GSO_GRE | SKB_GSO_GRE_CSUM) ||
-			     !(type & (SKB_GSO_UDP))))
-			goto out;
 
 		skb_shinfo(skb)->gso_segs = DIV_ROUND_UP(skb->len, mss);
 
diff --git a/net/ipv6/ip6_offload.c b/net/ipv6/ip6_offload.c
index f5eb184..9ad743b 100644
--- a/net/ipv6/ip6_offload.c
+++ b/net/ipv6/ip6_offload.c
@@ -69,24 +69,6 @@ static struct sk_buff *ipv6_gso_segment(struct sk_buff *skb,
 	bool encap, udpfrag;
 	int nhoff;
 
-	if (unlikely(skb_shinfo(skb)->gso_type &
-		     ~(SKB_GSO_TCPV4 |
-		       SKB_GSO_UDP |
-		       SKB_GSO_DODGY |
-		       SKB_GSO_TCP_ECN |
-		       SKB_GSO_TCP_FIXEDID |
-		       SKB_GSO_TCPV6 |
-		       SKB_GSO_GRE |
-		       SKB_GSO_GRE_CSUM |
-		       SKB_GSO_IPIP |
-		       SKB_GSO_SIT |
-		       SKB_GSO_UDP_TUNNEL |
-		       SKB_GSO_UDP_TUNNEL_CSUM |
-		       SKB_GSO_TUNNEL_REMCSUM |
-		       SKB_GSO_PARTIAL |
-		       0)))
-		goto out;
-
 	skb_reset_network_header(skb);
 	nhoff = skb_network_header(skb) - skb_mac_header(skb);
 	if (unlikely(!pskb_may_pull(skb, sizeof(*ipv6h))))
diff --git a/net/ipv6/udp_offload.c b/net/ipv6/udp_offload.c
index 5429f6b..ac858c4 100644
--- a/net/ipv6/udp_offload.c
+++ b/net/ipv6/udp_offload.c
@@ -36,19 +36,6 @@ static struct sk_buff *udp6_ufo_fragment(struct sk_buff *skb,
 
 	if (skb_gso_ok(skb, features | NETIF_F_GSO_ROBUST)) {
 		/* Packet is from an untrusted source, reset gso_segs. */
-		int type = skb_shinfo(skb)->gso_type;
-
-		if (unlikely(type & ~(SKB_GSO_UDP |
-				      SKB_GSO_DODGY |
-				      SKB_GSO_UDP_TUNNEL |
-				      SKB_GSO_UDP_TUNNEL_CSUM |
-				      SKB_GSO_TUNNEL_REMCSUM |
-				      SKB_GSO_GRE |
-				      SKB_GSO_GRE_CSUM |
-				      SKB_GSO_IPIP |
-				      SKB_GSO_SIT) ||
-			     !(type & (SKB_GSO_UDP))))
-			goto out;
 
 		skb_shinfo(skb)->gso_segs = DIV_ROUND_UP(skb->len, mss);
 
diff --git a/net/mpls/mpls_gso.c b/net/mpls/mpls_gso.c
index bbcf604..2055e57 100644
--- a/net/mpls/mpls_gso.c
+++ b/net/mpls/mpls_gso.c
@@ -26,15 +26,6 @@ static struct sk_buff *mpls_gso_segment(struct sk_buff *skb,
 	netdev_features_t mpls_features;
 	__be16 mpls_protocol;
 
-	if (unlikely(skb_shinfo(skb)->gso_type &
-				~(SKB_GSO_TCPV4 |
-				  SKB_GSO_TCPV6 |
-				  SKB_GSO_UDP |
-				  SKB_GSO_DODGY |
-				  SKB_GSO_TCP_FIXEDID |
-				  SKB_GSO_TCP_ECN)))
-		goto out;
-
 	/* Setup inner SKB. */
 	mpls_protocol = skb->protocol;
 	skb->protocol = skb->inner_protocol;
@@ -57,7 +48,7 @@ static struct sk_buff *mpls_gso_segment(struct sk_buff *skb,
 	 * skb_mac_gso_segment(), an indirect caller of this function.
 	 */
 	__skb_pull(skb, skb->data - skb_mac_header(skb));
-out:
+
 	return segs;
 }