net: bind() fix error return on wrong address family

Hi,

Reinhard Max also pointed out that the error should EAFNOSUPPORT according
to POSIX.

The Linux manpages have it as EINVAL, some other OSes (Minix, HPUX, perhaps BSD) use
EAFNOSUPPORT. Windows uses WSAEFAULT according to MSDN.

Other protocols error values in their af bind() methods in current mainline git as far
as a brief look shows:
	EAFNOSUPPORT: atm, appletalk, l2tp, llc, phonet, rxrpc
	EINVAL: ax25, bluetooth, decnet, econet, ieee802154, iucv, netlink, netrom, packet, rds, rose, unix, x25,
	No check?: can/raw, ipv6/raw, irda, l2tp/l2tp_ip

Ciao, Marcus
Signed-off-by: Marcus Meissner <meissner@suse.de>
Cc: Reinhard Max <max@suse.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv4/af_inet.c

@@ -465,8 +465,10 @@ int inet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
 	if (addr_len < sizeof(struct sockaddr_in))
 		goto out;
 
-	if (addr->sin_family != AF_INET)
+	if (addr->sin_family != AF_INET) {
+		err = -EAFNOSUPPORT;
 		goto out;
+	}
 
 	chk_addr_ret = inet_addr_type(sock_net(sk), addr->sin_addr.s_addr);
 

net/ipv6/af_inet6.c

@@ -274,7 +274,7 @@ int inet6_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
 		return -EINVAL;
 
 	if (addr->sin6_family != AF_INET6)
-		return -EINVAL;
+		return -EAFNOSUPPORT;
 
 	addr_type = ipv6_addr_type(&addr->sin6_addr);
 	if ((addr_type & IPV6_ADDR_MULTICAST) && sock->type == SOCK_STREAM)