diff -NurpP linux-2.6.31.5-vs2.3.0.36.21-1/net/ipv6/udp.c linux-2.6.31.5-vs2.3.0.36.21.5/net/ipv6/udp.c
--- linux-2.6.31.5-vs2.3.0.36.21-1/net/ipv6/udp.c	2009-09-10 16:11:43.000000000 +0200
+++ linux-2.6.31.5-vs2.3.0.36.21.5/net/ipv6/udp.c	2009-11-05 05:04:49.000000000 +0100
@@ -61,41 +61,50 @@ int ipv6_rcv_saddr_equal(const struct so
 	int addr_type = ipv6_addr_type(sk_rcv_saddr6);
 	int addr_type2 = sk2_rcv_saddr6 ? ipv6_addr_type(sk2_rcv_saddr6) : IPV6_ADDR_MAPPED;
 
-	if (sk2_ipv6only && !sk2_rcv_saddr6)
-		addr_type2 = IPV6_ADDR_ANY;
-
-	/* if both are mapped or any, treat as IPv4 */
-	if ((addr_type == IPV6_ADDR_MAPPED || (addr_type == IPV6_ADDR_ANY && !sk_ipv6only)) &&
-	    (addr_type2 == IPV6_ADDR_MAPPED || (addr_type2 == IPV6_ADDR_ANY && !sk2_ipv6only))) {
-		if (!sk_rcv_saddr && !sk2_rcv_saddr) {
-			if (nx_v4_addr_conflict(sk->sk_nx_info, sk2->sk_nx_info))
-				return 1;
-			else if (addr_type != IPV6_ADDR_ANY && sk2_rcv_saddr6)
-				return 0;
-			/* remaining cases are at least one ANY */
-		} else if (!sk_rcv_saddr)
-			return v4_addr_in_nx_info(sk->sk_nx_info, sk2_rcv_saddr, -1);
-		else if (!sk2_rcv_saddr)
-			return v4_addr_in_nx_info(sk2->sk_nx_info, sk_rcv_saddr, -1);
+	/* if both are mapped, treat as IPv4 */
+	if (addr_type == IPV6_ADDR_MAPPED && addr_type2 == IPV6_ADDR_MAPPED) {
+		if (!sk2_ipv6only &&
+			(!sk_rcv_saddr || !sk2_rcv_saddr ||
+			  sk_rcv_saddr == sk2_rcv_saddr))
+			goto vs_v4;
 		else
-			return (sk_rcv_saddr == sk2_rcv_saddr);
+			return 0;
 	}
 
-	if (!sk2_rcv_saddr6)
-		addr_type2 = IPV6_ADDR_ANY;
+	if (addr_type2 == IPV6_ADDR_ANY &&
+	    !(sk2_ipv6only && addr_type == IPV6_ADDR_MAPPED))
+		goto vs;
 
-	/* both are IPv6 */
-	if (addr_type == IPV6_ADDR_ANY && addr_type2 == IPV6_ADDR_ANY)
-		return nx_v6_addr_conflict(sk->sk_nx_info, sk2->sk_nx_info);
+	if (addr_type == IPV6_ADDR_ANY &&
+	    !(sk_ipv6only && addr_type2 == IPV6_ADDR_MAPPED))
+		goto vs;
 
-	if (addr_type == IPV6_ADDR_ANY)
-		return v6_addr_in_nx_info(sk->sk_nx_info,
-			sk2_rcv_saddr6 ? sk2_rcv_saddr6 : &in6addr_any, -1);
+	if (sk2_rcv_saddr6 &&
+	    ipv6_addr_equal(sk_rcv_saddr6, sk2_rcv_saddr6))
+		goto vs;
 
-	if (addr_type2 == IPV6_ADDR_ANY)
-		return v6_addr_in_nx_info(sk2->sk_nx_info, sk_rcv_saddr6, -1);
+	return 0;
 
-	return ipv6_addr_equal(sk_rcv_saddr6, sk2_rcv_saddr6);
+vs_v4:
+	if (!sk_rcv_saddr && !sk2_rcv_saddr)
+		return nx_v4_addr_conflict(sk->sk_nx_info, sk2->sk_nx_info);
+	if (!sk2_rcv_saddr)
+		return v4_addr_in_nx_info(sk->sk_nx_info, sk2_rcv_saddr, -1);
+	if (!sk_rcv_saddr)
+		return v4_addr_in_nx_info(sk2->sk_nx_info, sk_rcv_saddr, -1);
+	return 1;
+vs:
+	if (addr_type2 == IPV6_ADDR_ANY && addr_type == IPV6_ADDR_ANY)
+		return nx_v6_addr_conflict(sk->sk_nx_info, sk2->sk_nx_info);
+	else if (addr_type2 == IPV6_ADDR_ANY)
+		return v6_addr_in_nx_info(sk2->sk_nx_info, sk_rcv_saddr6, -1);
+	else if (addr_type == IPV6_ADDR_ANY) {
+		if (addr_type2 == IPV6_ADDR_MAPPED)
+			return nx_v4_addr_conflict(sk->sk_nx_info, sk2->sk_nx_info);
+		else
+			return v6_addr_in_nx_info(sk->sk_nx_info, sk2_rcv_saddr6, -1);
+	}
+	return 1;
 }
 
 int udp_v6_get_port(struct sock *sk, unsigned short snum)