net/ipv6: check for mistakenly passed in non-AF_INET6 sockaddrs

Same check as for IPv4, also do for IPv6.

(If you passed in a IPv4 sockaddr_in here, the sizeof check
 in the line before would have triggered already though.)

Signed-off-by: Marcus Meissner <meissner@suse.de>
Cc: Reinhard Max <max@suse.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/af_inet6.c b/net/ipv6/af_inet6.c
index b7919f9..d450a2f 100644
--- a/net/ipv6/af_inet6.c
+++ b/net/ipv6/af_inet6.c
@@ -272,6 +272,10 @@
 
 	if (addr_len < SIN6_LEN_RFC2133)
 		return -EINVAL;
+
+	if (addr->sin6_family != AF_INET6)
+		return -EINVAL;
+
 	addr_type = ipv6_addr_type(&addr->sin6_addr);
 	if ((addr_type & IPV6_ADDR_MULTICAST) && sock->type == SOCK_STREAM)
 		return -EINVAL;