geneve: ensure ECN info is handled properly in all tx/rx paths

Partially due to a pre-exising "thinko", the new metadata-based tx/rx
paths were handling ECN propagation differently than the traditional
tx/rx paths.  This patch removes the "thinko" (involving multiple
ip_hdr assignments) on the rx path and corrects the ECN handling on
both the rx and tx paths.

Signed-off-by: John W. Linville <linville@tuxdriver.com>
Reviewed-by: Jesse Gross <jesse@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/geneve.c b/drivers/net/geneve.c
index 8f1e915..4ce8b7b 100644 (file)
--- a/drivers/net/geneve.c
+++ b/drivers/net/geneve.c
@@ -126,6 +126,8 @@ static void geneve_rx(struct geneve_sock *gs, struct sk_buff *skb)
        __be32 addr;
        int err;
 
+       iph = ip_hdr(skb); /* outer IP header... */
+
        if (gs->collect_md) {
                static u8 zero_vni[3];
 
@@ -133,7 +135,6 @@ static void geneve_rx(struct geneve_sock *gs, struct sk_buff *skb)
                addr = 0;
        } else {
                vni = gnvh->vni;
-               iph = ip_hdr(skb); /* Still outer IP header... */
                addr = iph->saddr;
        }
 
@@ -178,7 +179,6 @@ static void geneve_rx(struct geneve_sock *gs, struct sk_buff *skb)
 
        skb_reset_network_header(skb);
 
-       iph = ip_hdr(skb); /* Now inner IP header... */
        err = IP_ECN_decapsulate(iph, skb);
 
        if (unlikely(err)) {
@@ -626,6 +626,7 @@ static netdev_tx_t geneve_xmit(struct sk_buff *skb, struct net_device *dev)
        struct geneve_sock *gs = geneve->sock;
        struct ip_tunnel_info *info = NULL;
        struct rtable *rt = NULL;
+       const struct iphdr *iip; /* interior IP header */
        struct flowi4 fl4;
        __u8 tos, ttl;
        __be16 sport;
@@ -653,6 +654,8 @@ static netdev_tx_t geneve_xmit(struct sk_buff *skb, struct net_device *dev)
        sport = udp_flow_src_port(geneve->net, skb, 1, USHRT_MAX, true);
        skb_reset_mac_header(skb);
 
+       iip = ip_hdr(skb);
+
        if (info) {
                const struct ip_tunnel_key *key = &info->key;
                u8 *opts = NULL;
@@ -668,19 +671,16 @@ static netdev_tx_t geneve_xmit(struct sk_buff *skb, struct net_device *dev)
                if (unlikely(err))
                        goto err;
 
-               tos = key->tos;
+               tos = ip_tunnel_ecn_encap(key->tos, iip, skb);
                ttl = key->ttl;
                df = key->tun_flags & TUNNEL_DONT_FRAGMENT ? htons(IP_DF) : 0;
        } else {
-               const struct iphdr *iip; /* interior IP header */
-
                udp_csum = false;
                err = geneve_build_skb(rt, skb, 0, geneve->vni,
                                       0, NULL, udp_csum);
                if (unlikely(err))
                        goto err;
 
-               iip = ip_hdr(skb);
                tos = ip_tunnel_ecn_encap(fl4.flowi4_tos, iip, skb);
                ttl = geneve->ttl;
                if (!ttl && IN_MULTICAST(ntohl(fl4.daddr)))