X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=datapath%2Fvport.c;h=8ef96f73e1fc6ea7e77cb1881d5617e0be93ab85;hb=13521ff59379b6a7a91be18ce8d903cd698694b3;hp=517e871ee3d25af55092087124fdceca10860e4e;hpb=ed099e921e30d3720c5ad7d1b4f911bb23911bf3;p=openvswitch

diff --git a/datapath/vport.c b/datapath/vport.c
index 517e871e..8ef96f73 100644
--- a/datapath/vport.c
+++ b/datapath/vport.c
@@ -605,12 +605,14 @@ int vport_get_iflink(const struct vport *vport)
  *
  * @vport: vport from which to retrieve MTU
  *
- * Retrieves the MTU of the given device.
- *
- * Must be called with RTNL lock or rcu_read_lock.
+ * Retrieves the MTU of the given device.  Returns 0 if @vport does not have an
+ * MTU (as e.g. some tunnels do not).  Either RTNL lock or rcu_read_lock must
+ * be held.
  */
 int vport_get_mtu(const struct vport *vport)
 {
+	if (!vport->ops->get_mtu)
+		return 0;
 	return vport->ops->get_mtu(vport);
 }
 
@@ -625,7 +627,8 @@ int vport_get_mtu(const struct vport *vport)
  * vport-specific attributes to @skb.
  *
  * Returns 0 if successful, -EMSGSIZE if @skb has insufficient room, or another
- * negative error code if a real error occurred.
+ * negative error code if a real error occurred.  If an error occurs, @skb is
+ * left unmodified.
  *
  * Must be called with RTNL lock or rcu_read_lock.
  */
@@ -639,8 +642,10 @@ int vport_get_options(const struct vport *vport, struct sk_buff *skb)
 
 	if (vport->ops->get_options) {
 		int err = vport->ops->get_options(vport, skb);
-		if (err)
+		if (err) {
+			nla_nest_cancel(skb, nla);
 			return err;
+		}
 	}
 
 	nla_nest_end(skb, nla);
@@ -707,7 +712,7 @@ int vport_send(struct vport *vport, struct sk_buff *skb)
 	int sent;
 
 	mtu = vport_get_mtu(vport);
-	if (unlikely(packet_length(skb) > mtu && !skb_is_gso(skb))) {
+	if (mtu && unlikely(packet_length(skb) > mtu && !skb_is_gso(skb))) {
 		if (net_ratelimit())
 			pr_warn("%s: dropped over-mtu packet: %d > %d\n",
 				dp_name(vport->dp), packet_length(skb), mtu);