diff --git a/include/linux/ipv6.h b/include/linux/ipv6.h
index 297853c..02d14a3 100644
--- a/include/linux/ipv6.h
+++ b/include/linux/ipv6.h
@@ -242,6 +242,9 @@
 	struct in6_addr 	rcv_saddr;
 	struct in6_addr		daddr;
 	struct in6_addr		*daddr_cache;
+#ifdef CONFIG_IPV6_SUBTREES
+	struct in6_addr		*saddr_cache;
+#endif
 
 	__u32			flow_label;
 	__u32			frag_size;
diff --git a/include/net/ip6_route.h b/include/net/ip6_route.h
index 249ce45..0d40f84 100644
--- a/include/net/ip6_route.h
+++ b/include/net/ip6_route.h
@@ -144,21 +144,24 @@
  *	Store a destination cache entry in a socket
  */
 static inline void __ip6_dst_store(struct sock *sk, struct dst_entry *dst,
-				   struct in6_addr *daddr)
+				   struct in6_addr *daddr, struct in6_addr *saddr)
 {
 	struct ipv6_pinfo *np = inet6_sk(sk);
 	struct rt6_info *rt = (struct rt6_info *) dst;
 
 	sk_setup_caps(sk, dst);
 	np->daddr_cache = daddr;
+#ifdef CONFIG_IPV6_SUBTREES
+	np->saddr_cache = saddr;
+#endif
 	np->dst_cookie = rt->rt6i_node ? rt->rt6i_node->fn_sernum : 0;
 }
 
 static inline void ip6_dst_store(struct sock *sk, struct dst_entry *dst,
-				 struct in6_addr *daddr)
+				 struct in6_addr *daddr, struct in6_addr *saddr)
 {
 	write_lock(&sk->sk_dst_lock);
-	__ip6_dst_store(sk, dst, daddr);
+	__ip6_dst_store(sk, dst, daddr, saddr);
 	write_unlock(&sk->sk_dst_lock);
 }
 
diff --git a/net/dccp/ipv6.c b/net/dccp/ipv6.c
index 231bc7c..f9c5e12 100644
--- a/net/dccp/ipv6.c
+++ b/net/dccp/ipv6.c
@@ -231,7 +231,7 @@
 	ipv6_addr_copy(&np->saddr, saddr);
 	inet->rcv_saddr = LOOPBACK4_IPV6;
 
-	__ip6_dst_store(sk, dst, NULL);
+	__ip6_dst_store(sk, dst, NULL, NULL);
 
 	icsk->icsk_ext_hdr_len = 0;
 	if (np->opt != NULL)
@@ -872,7 +872,7 @@
 	 * comment in that function for the gory details. -acme
 	 */
 
-	__ip6_dst_store(newsk, dst, NULL);
+	__ip6_dst_store(newsk, dst, NULL, NULL);
 	newsk->sk_route_caps = dst->dev->features & ~(NETIF_F_IP_CSUM |
 						      NETIF_F_TSO);
 	newdp6 = (struct dccp6_sock *)newsk;
diff --git a/net/ipv6/af_inet6.c b/net/ipv6/af_inet6.c
index 2ff600c..57ee5dd 100644
--- a/net/ipv6/af_inet6.c
+++ b/net/ipv6/af_inet6.c
@@ -659,7 +659,7 @@
 			return err;
 		}
 
-		__ip6_dst_store(sk, dst, NULL);
+		__ip6_dst_store(sk, dst, NULL, NULL);
 	}
 
 	return 0;
diff --git a/net/ipv6/datagram.c b/net/ipv6/datagram.c
index c73508e..8561b9d 100644
--- a/net/ipv6/datagram.c
+++ b/net/ipv6/datagram.c
@@ -193,7 +193,12 @@
 
 	ip6_dst_store(sk, dst,
 		      ipv6_addr_equal(&fl.fl6_dst, &np->daddr) ?
-		      &np->daddr : NULL);
+		      &np->daddr : NULL,
+#ifdef CONFIG_IPV6_SUBTREES
+		      ipv6_addr_equal(&fl.fl6_src, &np->saddr) ?
+		      &np->saddr :
+#endif
+		      NULL);
 
 	sk->sk_state = TCP_ESTABLISHED;
 out:
diff --git a/net/ipv6/inet6_connection_sock.c b/net/ipv6/inet6_connection_sock.c
index 7a51a25..827f41d 100644
--- a/net/ipv6/inet6_connection_sock.c
+++ b/net/ipv6/inet6_connection_sock.c
@@ -186,7 +186,7 @@
 			return err;
 		}
 
-		__ip6_dst_store(sk, dst, NULL);
+		__ip6_dst_store(sk, dst, NULL, NULL);
 	}
 
 	skb->dst = dst_clone(dst);
diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
index 0a18cb6..2a376b7 100644
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -762,6 +762,9 @@
 	 * 2. oif also should be the same.
 	 */
 	if (ip6_rt_check(&rt->rt6i_dst, &fl->fl6_dst, np->daddr_cache) ||
+#ifdef CONFIG_IPV6_SUBTREES
+	    ip6_rt_check(&rt->rt6i_src, &fl->fl6_src, np->saddr_cache) ||
+#endif
 	    (fl->oif && fl->oif != dst->dev->ifindex)) {
 		dst_release(dst);
 		dst = NULL;
diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 7f1b660..2b18918 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -272,7 +272,7 @@
 	inet->rcv_saddr = LOOPBACK4_IPV6;
 
 	sk->sk_gso_type = SKB_GSO_TCPV6;
-	__ip6_dst_store(sk, dst, NULL);
+	__ip6_dst_store(sk, dst, NULL, NULL);
 
 	icsk->icsk_ext_hdr_len = 0;
 	if (np->opt)
@@ -954,7 +954,7 @@
 	 */
 
 	newsk->sk_gso_type = SKB_GSO_TCPV6;
-	__ip6_dst_store(newsk, dst, NULL);
+	__ip6_dst_store(newsk, dst, NULL, NULL);
 
 	newtcp6sk = (struct tcp6_sock *)newsk;
 	inet_sk(newsk)->pinet6 = &newtcp6sk->inet6;
diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index eb9e1b3..b9cc55c 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -847,7 +847,12 @@
 		if (connected) {
 			ip6_dst_store(sk, dst,
 				      ipv6_addr_equal(&fl->fl6_dst, &np->daddr) ?
-				      &np->daddr : NULL);
+				      &np->daddr : NULL,
+#ifdef CONFIG_IPV6_SUBTREES
+				      ipv6_addr_equal(&fl->fl6_src, &np->saddr) ?
+				      &np->saddr :
+#endif
+				      NULL);
 		} else {
 			dst_release(dst);
 		}