tunneling: Always use skb->len for PMTUD.

[sliver-openvswitch.git] / datapath / tunnel.c

diff --git a/datapath/tunnel.c b/datapath/tunnel.c
index 7bf46e0..40577fb 100644 (file)
--- a/datapath/tunnel.c
+++ b/datapath/tunnel.c
@@ -718,6 +718,10 @@ static bool check_mtu(struct sk_buff *skb,
        bool pmtud = mutable->flags & TNL_F_PMTUD;
        __be16 frag_off = 0;
        int mtu = 0;
+       unsigned int packet_length = skb->len - ETH_HLEN;
+
+       if (eth_hdr(skb)->h_proto == htons(ETH_P_8021Q))
+               packet_length -= VLAN_HLEN;
 
        if (pmtud) {
                frag_off = htons(IP_DF);
@@ -737,7 +741,7 @@ static bool check_mtu(struct sk_buff *skb,
                if (pmtud && iph->frag_off & htons(IP_DF)) {
                        mtu = max(mtu, IP_MIN_MTU);
 
-                       if (ntohs(iph->tot_len) > mtu &&
+                       if (packet_length > mtu &&
                            tnl_frag_needed(vport, mutable, skb, mtu,
                                            OVS_CB(skb)->tun_id))
                                return false;
@@ -745,10 +749,6 @@ static bool check_mtu(struct sk_buff *skb,
        }
 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
        else if (skb->protocol == htons(ETH_P_IPV6)) {
-               unsigned int packet_length = skb->len - ETH_HLEN
-                       - (eth_hdr(skb)->h_proto == htons(ETH_P_8021Q) ?
-                               VLAN_HLEN : 0);
-
                /* IPv6 requires PMTUD if the packet is above the minimum MTU. */
                if (packet_length > IPV6_MIN_MTU)
                        frag_off = htons(IP_DF);