diff --git a/net/ipv6/ip6_input.c b/net/ipv6/ip6_input.c
index 027c7ff6f1e5370bc0e84d8e3daeb996875a431c..a46c64eb0a660b47b132e4b2346e1c112cc05759 100644
--- a/net/ipv6/ip6_input.c
+++ b/net/ipv6/ip6_input.c
@@ -111,6 +111,14 @@ int ipv6_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt
 	    ipv6_addr_loopback(&hdr->daddr))
 		goto err;
 
+	/*
+	 * RFC4291 2.7
+	 * Multicast addresses must not be used as source addresses in IPv6
+	 * packets or appear in any Routing header.
+	 */
+	if (ipv6_addr_is_multicast(&hdr->saddr))
+		goto err;
+
 	skb->transport_header = skb->network_header + sizeof(*hdr);
 	IP6CB(skb)->nhoff = offsetof(struct ipv6hdr, nexthdr);