Subject: [PATCH 08/16] udptunnel: Add SKB_GSO_UDP_TUNNEL during gro_complete.

From: Jesse Gross <[email-masked]>
Date: Mon, 10 Nov 2014 11:45:13 -0800

[ Upstream commit cfdf1e1ba5bf55e095cf4bcaa9585c4759f239e8 ]

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 <[email-masked]>
Signed-off-by: David S. Miller <[email-masked]>
---
 drivers/net/vxlan.c      | 2 ++
 include/net/udp_tunnel.h | 9 +++++++++
 2 files changed, 11 insertions(+)

diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c
index b483127..6ab737b 100644
--- a/drivers/net/vxlan.c
+++ b/drivers/net/vxlan.c
@@ -620,6 +620,8 @@ static int vxlan_gro_complete(struct sk_buff *skb, int nhoff)
 	int vxlan_len  = sizeof(struct vxlanhdr) + sizeof(struct ethhdr);
 	int err = -ENOSYS;
 
+	udp_tunnel_gro_complete(skb, nhoff);
+
 	eh = (struct ethhdr *)(skb->data + nhoff + sizeof(struct vxlanhdr));
 	type = eh->h_proto;
 
diff --git a/include/net/udp_tunnel.h b/include/net/udp_tunnel.h
index ffd69cb..55003b8 100644
--- a/include/net/udp_tunnel.h
+++ b/include/net/udp_tunnel.h
@@ -26,6 +26,15 @@ struct udp_port_cfg {
 				use_udp6_rx_checksums:1;
 };
 
+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;
+}
+
 int udp_sock_create(struct net *net, struct udp_port_cfg *cfg,
 		    struct socket **sockp);
 
-- 
1.7.11.7