udp: Set SKB_GSO_UDP_TUNNEL* in UDP GRO path

Properly set GSO types and skb->encapsulation in the UDP tunnel GRO
complete so that packets are properly represented for GSO. This sets
SKB_GSO_UDP_TUNNEL or SKB_GSO_UDP_TUNNEL_CSUM depending on whether
non-zero checksums were received, and sets SKB_GSO_TUNNEL_REMCSUM if
the remote checksum option was processed.

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

2 files changed, 17 insertions, 2 deletions

diff --git a/net/ipv4/udp_offload.c b/net/ipv4/udp_offload.c
index d10f6f4ead27..4915d8284a86 100644
--- a/net/ipv4/udp_offload.c
+++ b/net/ipv4/udp_offload.c
@@ -402,6 +402,13 @@ int udp_gro_complete(struct sk_buff *skb, int nhoff)
         }
 
         rcu_read_unlock();
+
+        if (skb->remcsum_offload)
+                skb_shinfo(skb)->gso_type |= SKB_GSO_TUNNEL_REMCSUM;
+
+        skb->encapsulation = 1;
+        skb_set_inner_mac_header(skb, nhoff + sizeof(struct udphdr));
+
         return err;
 }
 
@@ -410,9 +417,13 @@ static int udp4_gro_complete(struct sk_buff *skb, int nhoff)
         const struct iphdr *iph = ip_hdr(skb);
         struct udphdr *uh = (struct udphdr *)(skb->data + nhoff);
 
-        if (uh->check)
+        if (uh->check) {
+                skb_shinfo(skb)->gso_type |= SKB_GSO_UDP_TUNNEL_CSUM;
                 uh->check = ~udp_v4_check(skb->len - nhoff, iph->saddr,
                                           iph->daddr, 0);
+        } else {
+                skb_shinfo(skb)->gso_type |= SKB_GSO_UDP_TUNNEL;
+        }
 
         return udp_gro_complete(skb, nhoff);
 }
diff --git a/net/ipv6/udp_offload.c b/net/ipv6/udp_offload.c
index a56276996b72..ab889bb16b3c 100644
--- a/net/ipv6/udp_offload.c
+++ b/net/ipv6/udp_offload.c
@@ -161,9 +161,13 @@ static int udp6_gro_complete(struct sk_buff *skb, int nhoff)
         const struct ipv6hdr *ipv6h = ipv6_hdr(skb);
         struct udphdr *uh = (struct udphdr *)(skb->data + nhoff);
 
-        if (uh->check)
+        if (uh->check) {
+                skb_shinfo(skb)->gso_type |= SKB_GSO_UDP_TUNNEL_CSUM;
                 uh->check = ~udp_v6_check(skb->len - nhoff, &ipv6h->saddr,
                                           &ipv6h->daddr, 0);
+        } else {
+                skb_shinfo(skb)->gso_type |= SKB_GSO_UDP_TUNNEL;
+        }
 
         return udp_gro_complete(skb, nhoff);
 }