Index: linux-2.6.26.8/net/ipv4/ip_gre.c
===================================================================
--- linux-2.6.26.8.orig/net/ipv4/ip_gre.c	2009-01-08 12:54:44.000000000 +0200
+++ linux-2.6.26.8/net/ipv4/ip_gre.c	2009-01-08 15:30:38.000000000 +0200
@@ -162,41 +162,65 @@
 
 /* Given src, dst and key, find appropriate for input tunnel. */
 
-static struct ip_tunnel * ipgre_tunnel_lookup(struct net *net,
+static struct ip_tunnel * ipgre_tunnel_lookup(struct net_device *dev,
 		__be32 remote, __be32 local, __be32 key)
 {
+	struct net *net = dev_net(dev);
+	int link = dev->ifindex;
 	unsigned h0 = HASH(remote);
 	unsigned h1 = HASH(key);
-	struct ip_tunnel *t;
+	struct ip_tunnel *t, *tlinkless = NULL;
 	struct ipgre_net *ign = net_generic(net, ipgre_net_id);
 
 	for (t = ign->tunnels_r_l[h0^h1]; t; t = t->next) {
-		if (local == t->parms.iph.saddr && remote == t->parms.iph.daddr) {
-			if (t->parms.i_key == key && (t->dev->flags&IFF_UP))
+		if (local == t->parms.iph.saddr &&
+		    remote == t->parms.iph.daddr &&
+		    key == t->parms.i_key &&
+		    (t->dev->flags & IFF_UP)) {
+			if (link == t->parms.link)
 				return t;
+			if (tlinkless == NULL)
+				tlinkless = t;
 		}
 	}
 	for (t = ign->tunnels_r[h0^h1]; t; t = t->next) {
-		if (remote == t->parms.iph.daddr) {
-			if (t->parms.i_key == key && (t->dev->flags&IFF_UP))
+		if (remote == t->parms.iph.daddr &&
+		    key == t->parms.i_key &&
+		    (t->dev->flags&IFF_UP)) {
+			if (link == t->parms.link)
 				return t;
+			if (tlinkless == NULL)
+				tlinkless = t;
 		}
 	}
 	for (t = ign->tunnels_l[h1]; t; t = t->next) {
-		if (local == t->parms.iph.saddr ||
-		     (local == t->parms.iph.daddr &&
-		      ipv4_is_multicast(local))) {
-			if (t->parms.i_key == key && (t->dev->flags&IFF_UP))
+		if ((local == t->parms.iph.saddr ||
+		     (local == t->parms.iph.daddr && ipv4_is_multicast(local))) &&
+		    key == t->parms.i_key &&
+		    (t->dev->flags & IFF_UP)) {
+			if (link == t->parms.link)
 				return t;
+			if (tlinkless == NULL)
+				tlinkless = t;
 		}
 	}
+
 	for (t = ign->tunnels_wc[h1]; t; t = t->next) {
-		if (t->parms.i_key == key && (t->dev->flags&IFF_UP))
-			return t;
+		if (t->parms.i_key == key &&
+		    (t->dev->flags & IFF_UP)) {
+			if (link == t->parms.link)
+				return t;
+			if (tlinkless == NULL)
+				tlinkless = t;
+		}
 	}
 
-	if (ign->fb_tunnel_dev->flags&IFF_UP)
+	if (tlinkless != NULL)
+		return tlinkless;
+
+	if (ign->fb_tunnel_dev->flags & IFF_UP)
 		return netdev_priv(ign->fb_tunnel_dev);
+
 	return NULL;
 }
 
@@ -255,16 +279,18 @@
 	__be32 remote = parms->iph.daddr;
 	__be32 local = parms->iph.saddr;
 	__be32 key = parms->i_key;
+	int link = parms->link;
 	struct ip_tunnel *t, **tp, *nt;
 	struct net_device *dev;
 	char name[IFNAMSIZ];
 	struct ipgre_net *ign = net_generic(net, ipgre_net_id);
 
 	for (tp = __ipgre_bucket(ign, parms); (t = *tp) != NULL; tp = &t->next) {
-		if (local == t->parms.iph.saddr && remote == t->parms.iph.daddr) {
-			if (key == t->parms.i_key)
-				return t;
-		}
+		if (local == t->parms.iph.saddr &&
+		    remote == t->parms.iph.daddr &&
+		    key == t->parms.i_key &&
+		    link == t->parms.link)
+			return t;
 	}
 	if (!create)
 		return NULL;
@@ -379,7 +405,7 @@
 	}
 
 	read_lock(&ipgre_lock);
-	t = ipgre_tunnel_lookup(dev_net(skb->dev), iph->daddr, iph->saddr,
+	t = ipgre_tunnel_lookup(skb->dev, iph->daddr, iph->saddr,
 			(flags&GRE_KEY) ?
 			*(((__be32*)p) + (grehlen>>2) - 1) : 0);
 	if (t == NULL || t->parms.iph.daddr == 0 ||
@@ -471,7 +497,7 @@
 	}
 
 	read_lock(&ipgre_lock);
-	if ((tunnel = ipgre_tunnel_lookup(dev_net(skb->dev),
+	if ((tunnel = ipgre_tunnel_lookup(skb->dev,
 					iph->saddr, iph->daddr, key)) != NULL) {
 		secpath_reset(skb);