[NETNS]: Disable multicaststing configuration inside non-initial namespace.

Do not calls hooks from device notifiers and disallow configuration from
ioctl/netlink layer.
Signed-off-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv4/igmp.c

@@ -1198,6 +1198,9 @@ void ip_mc_inc_group(struct in_device *in_dev, __be32 addr)
 
 	ASSERT_RTNL();
 
+	if (in_dev->dev->nd_net != &init_net)
+		return;
+
 	for (im=in_dev->mc_list; im; im=im->next) {
 		if (im->multiaddr == addr) {
 			im->users++;
@@ -1277,6 +1280,9 @@ void ip_mc_dec_group(struct in_device *in_dev, __be32 addr)
 
 	ASSERT_RTNL();
 
+	if (in_dev->dev->nd_net != &init_net)
+		return;
+
 	for (ip=&in_dev->mc_list; (i=*ip)!=NULL; ip=&i->next) {
 		if (i->multiaddr==addr) {
 			if (--i->users == 0) {
@@ -1304,6 +1310,9 @@ void ip_mc_down(struct in_device *in_dev)
 
 	ASSERT_RTNL();
 
+	if (in_dev->dev->nd_net != &init_net)
+		return;
+
 	for (i=in_dev->mc_list; i; i=i->next)
 		igmp_group_dropped(i);
 
@@ -1324,6 +1333,9 @@ void ip_mc_init_dev(struct in_device *in_dev)
 {
 	ASSERT_RTNL();
 
+	if (in_dev->dev->nd_net != &init_net)
+		return;
+
 	in_dev->mc_tomb = NULL;
 #ifdef CONFIG_IP_MULTICAST
 	in_dev->mr_gq_running = 0;
@@ -1347,6 +1359,9 @@ void ip_mc_up(struct in_device *in_dev)
 
 	ASSERT_RTNL();
 
+	if (in_dev->dev->nd_net != &init_net)
+		return;
+
 	ip_mc_inc_group(in_dev, IGMP_ALL_HOSTS);
 
 	for (i=in_dev->mc_list; i; i=i->next)
@@ -1363,6 +1378,9 @@ void ip_mc_destroy_dev(struct in_device *in_dev)
 
 	ASSERT_RTNL();
 
+	if (in_dev->dev->nd_net != &init_net)
+		return;
+
 	/* Deactivate timers */
 	ip_mc_down(in_dev);
 
@@ -1744,6 +1762,9 @@ int ip_mc_join_group(struct sock *sk , struct ip_mreqn *imr)
 	if (!ipv4_is_multicast(addr))
 		return -EINVAL;
 
+	if (sk->sk_net != &init_net)
+		return -EPROTONOSUPPORT;
+
 	rtnl_lock();
 
 	in_dev = ip_mc_find_dev(imr);
@@ -1812,6 +1833,9 @@ int ip_mc_leave_group(struct sock *sk, struct ip_mreqn *imr)
 	u32 ifindex;
 	int ret = -EADDRNOTAVAIL;
 
+	if (sk->sk_net != &init_net)
+		return -EPROTONOSUPPORT;
+
 	rtnl_lock();
 	in_dev = ip_mc_find_dev(imr);
 	ifindex = imr->imr_ifindex;
@@ -1857,6 +1881,9 @@ int ip_mc_source(int add, int omode, struct sock *sk, struct
 	if (!ipv4_is_multicast(addr))
 		return -EINVAL;
 
+	if (sk->sk_net != &init_net)
+		return -EPROTONOSUPPORT;
+
 	rtnl_lock();
 
 	imr.imr_multiaddr.s_addr = mreqs->imr_multiaddr;
@@ -1990,6 +2017,9 @@ int ip_mc_msfilter(struct sock *sk, struct ip_msfilter *msf, int ifindex)
 	    msf->imsf_fmode != MCAST_EXCLUDE)
 		return -EINVAL;
 
+	if (sk->sk_net != &init_net)
+		return -EPROTONOSUPPORT;
+
 	rtnl_lock();
 
 	imr.imr_multiaddr.s_addr = msf->imsf_multiaddr;
@@ -2070,6 +2100,9 @@ int ip_mc_msfget(struct sock *sk, struct ip_msfilter *msf,
 	if (!ipv4_is_multicast(addr))
 		return -EINVAL;
 
+	if (sk->sk_net != &init_net)
+		return -EPROTONOSUPPORT;
+
 	rtnl_lock();
 
 	imr.imr_multiaddr.s_addr = msf->imsf_multiaddr;
@@ -2132,6 +2165,9 @@ int ip_mc_gsfget(struct sock *sk, struct group_filter *gsf,
 	if (!ipv4_is_multicast(addr))
 		return -EINVAL;
 
+	if (sk->sk_net != &init_net)
+		return -EPROTONOSUPPORT;
+
 	rtnl_lock();
 
 	err = -EADDRNOTAVAIL;
@@ -2216,6 +2252,9 @@ void ip_mc_drop_socket(struct sock *sk)
 	if (inet->mc_list == NULL)
 		return;
 
+	if (sk->sk_net != &init_net)
+		return;
+
 	rtnl_lock();
 	while ((iml = inet->mc_list) != NULL) {
 		struct in_device *in_dev;