udptunnel: Add SKB_GSO_UDP_TUNNEL during gro_complete.

When doing GRO processing for UDP tunnels, we never add
SKB_GSO_UDP_TUNNEL to gso_type - only the type of the inner protocol
is added (such as SKB_GSO_TCPV4). The result is that if the packet is
later resegmented we will do GSO but not treat it as a tunnel. This
results in UDP fragmentation of the outer header instead of (i.e.) TCP
segmentation of the inner header as was originally on the wire.

Signed-off-by: Jesse Gross <jesse@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 9 insertions, 0 deletions

diff --git a/include/net/udp_tunnel.h b/include/net/udp_tunnel.h
index a47790bcaa38..2a50a70ef587 100644
--- a/include/net/udp_tunnel.h
+++ b/include/net/udp_tunnel.h
@@ -100,6 +100,15 @@ static inline struct sk_buff *udp_tunnel_handle_offloads(struct sk_buff *skb,
         return iptunnel_handle_offloads(skb, udp_csum, type);
 }
 
+static inline void udp_tunnel_gro_complete(struct sk_buff *skb, int nhoff)
+{
+        struct udphdr *uh;
+
+        uh = (struct udphdr *)(skb->data + nhoff - sizeof(struct udphdr));
+        skb_shinfo(skb)->gso_type |= uh->check ?
+                                SKB_GSO_UDP_TUNNEL_CSUM : SKB_GSO_UDP_TUNNEL;
+}
+
 static inline void udp_tunnel_encap_enable(struct socket *sock)
 {
 #if IS_ENABLED(CONFIG_IPV6)