[NETNS][IPV6] af_inet6 - allow socket creation per namespace

Allow creation of IPv6 raw and datagram sockets in network namespaces
other than init_net.

Signed-off-by: Benjamin Thery <benjamin.thery@bull.net>
Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/af_inet6.c b/net/ipv6/af_inet6.c
index af5b307..430bbd2 100644
--- a/net/ipv6/af_inet6.c
+++ b/net/ipv6/af_inet6.c
@@ -92,9 +92,6 @@
 	int try_loading_module = 0;
 	int err;
 
-	if (net != &init_net)
-		return -EAFNOSUPPORT;
-
 	if (sock->type != SOCK_RAW &&
 	    sock->type != SOCK_DGRAM &&
 	    !inet_ehash_secret)
@@ -248,6 +245,7 @@
 	struct sock *sk = sock->sk;
 	struct inet_sock *inet = inet_sk(sk);
 	struct ipv6_pinfo *np = inet6_sk(sk);
+	struct net *net = sk->sk_net;
 	__be32 v4addr = 0;
 	unsigned short snum;
 	int addr_type = 0;
@@ -278,7 +276,7 @@
 	/* Check if the address belongs to the host. */
 	if (addr_type == IPV6_ADDR_MAPPED) {
 		v4addr = addr->sin6_addr.s6_addr32[3];
-		if (inet_addr_type(&init_net, v4addr) != RTN_LOCAL) {
+		if (inet_addr_type(net, v4addr) != RTN_LOCAL) {
 			err = -EADDRNOTAVAIL;
 			goto out;
 		}
@@ -300,7 +298,7 @@
 					err = -EINVAL;
 					goto out;
 				}
-				dev = dev_get_by_index(&init_net, sk->sk_bound_dev_if);
+				dev = dev_get_by_index(net, sk->sk_bound_dev_if);
 				if (!dev) {
 					err = -ENODEV;
 					goto out;
@@ -312,7 +310,7 @@
 			 */
 			v4addr = LOOPBACK4_IPV6;
 			if (!(addr_type & IPV6_ADDR_MULTICAST))	{
-				if (!ipv6_chk_addr(&init_net, &addr->sin6_addr,
+				if (!ipv6_chk_addr(net, &addr->sin6_addr,
 						   dev, 0)) {
 					if (dev)
 						dev_put(dev);