[NET]: Make the loopback device per network namespace.

This patch makes loopback_dev per network namespace.  Adding
code to create a different loopback device for each network
namespace and adding the code to free a loopback device
when a network namespace exits.

This patch modifies all users the loopback_dev so they
access it as init_net.loopback_dev, keeping all of the
code compiling and working.  A later pass will be needed to
update the users to use something other than the initial network
namespace.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

4 files changed, 17 insertions, 17 deletions

diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index b43574f..6d5c3c2 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -2410,7 +2410,7 @@ static int addrconf_ifdown(struct net_device *dev, int how)
 
 	ASSERT_RTNL();
 
-	if (dev == loopback_dev && how == 1)
+	if (dev == init_net.loopback_dev && how == 1)
 		how = 0;
 
 	rt6_ifdown(dev);
@@ -4212,19 +4212,19 @@ int __init addrconf_init(void)
 	 * device and it being up should be removed.
 	 */
 	rtnl_lock();
-	if (!ipv6_add_dev(loopback_dev))
+	if (!ipv6_add_dev(init_net.loopback_dev))
 		err = -ENOMEM;
 	rtnl_unlock();
 	if (err)
 		return err;
 
-	ip6_null_entry.u.dst.dev = loopback_dev;
-	ip6_null_entry.rt6i_idev = in6_dev_get(loopback_dev);
+	ip6_null_entry.u.dst.dev = init_net.loopback_dev;
+	ip6_null_entry.rt6i_idev = in6_dev_get(init_net.loopback_dev);
 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
-	ip6_prohibit_entry.u.dst.dev = loopback_dev;
-	ip6_prohibit_entry.rt6i_idev = in6_dev_get(loopback_dev);
-	ip6_blk_hole_entry.u.dst.dev = loopback_dev;
-	ip6_blk_hole_entry.rt6i_idev = in6_dev_get(loopback_dev);
+	ip6_prohibit_entry.u.dst.dev = init_net.loopback_dev;
+	ip6_prohibit_entry.rt6i_idev = in6_dev_get(init_net.loopback_dev);
+	ip6_blk_hole_entry.u.dst.dev = init_net.loopback_dev;
+	ip6_blk_hole_entry.rt6i_idev = in6_dev_get(init_net.loopback_dev);
 #endif
 
 	register_netdevice_notifier(&ipv6_dev_notf);
@@ -4279,7 +4279,7 @@ void __exit addrconf_cleanup(void)
 			continue;
 		addrconf_ifdown(dev, 1);
 	}
-	addrconf_ifdown(loopback_dev, 2);
+	addrconf_ifdown(init_net.loopback_dev, 2);
 
 	/*
 	 *	Check hash table.
diff --git a/net/ipv6/netfilter/ip6t_REJECT.c b/net/ipv6/netfilter/ip6t_REJECT.c
index 5086053..3fd08d5 100644
--- a/net/ipv6/netfilter/ip6t_REJECT.c
+++ b/net/ipv6/netfilter/ip6t_REJECT.c
@@ -167,7 +167,7 @@ static inline void
 send_unreach(struct sk_buff *skb_in, unsigned char code, unsigned int hooknum)
 {
 	if (hooknum == NF_IP6_LOCAL_OUT && skb_in->dev == NULL)
-		skb_in->dev = loopback_dev;
+		skb_in->dev = init_net.loopback_dev;
 
 	icmpv6_send(skb_in, ICMPV6_DEST_UNREACH, code, 0, NULL);
 }
diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index a7a21a7..6ff19f9 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -221,8 +221,8 @@ static void ip6_dst_ifdown(struct dst_entry *dst, struct net_device *dev,
 	struct rt6_info *rt = (struct rt6_info *)dst;
 	struct inet6_dev *idev = rt->rt6i_idev;
 
-	if (dev != loopback_dev && idev != NULL && idev->dev == dev) {
-		struct inet6_dev *loopback_idev = in6_dev_get(loopback_dev);
+	if (dev != init_net.loopback_dev && idev != NULL && idev->dev == dev) {
+		struct inet6_dev *loopback_idev = in6_dev_get(init_net.loopback_dev);
 		if (loopback_idev != NULL) {
 			rt->rt6i_idev = loopback_idev;
 			in6_dev_put(idev);
@@ -1185,12 +1185,12 @@ int ip6_route_add(struct fib6_config *cfg)
 	if ((cfg->fc_flags & RTF_REJECT) ||
 	    (dev && (dev->flags&IFF_LOOPBACK) && !(addr_type&IPV6_ADDR_LOOPBACK))) {
 		/* hold loopback dev/idev if we haven't done so. */
-		if (dev != loopback_dev) {
+		if (dev != init_net.loopback_dev) {
 			if (dev) {
 				dev_put(dev);
 				in6_dev_put(idev);
 			}
-			dev = loopback_dev;
+			dev = init_net.loopback_dev;
 			dev_hold(dev);
 			idev = in6_dev_get(dev);
 			if (!idev) {
@@ -1894,13 +1894,13 @@ struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev,
 	if (rt == NULL)
 		return ERR_PTR(-ENOMEM);
 
-	dev_hold(loopback_dev);
+	dev_hold(init_net.loopback_dev);
 	in6_dev_hold(idev);
 
 	rt->u.dst.flags = DST_HOST;
 	rt->u.dst.input = ip6_input;
 	rt->u.dst.output = ip6_output;
-	rt->rt6i_dev = loopback_dev;
+	rt->rt6i_dev = init_net.loopback_dev;
 	rt->rt6i_idev = idev;
 	rt->u.dst.metrics[RTAX_MTU-1] = ipv6_get_mtu(rt->rt6i_dev);
 	rt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(dst_mtu(&rt->u.dst));
diff --git a/net/ipv6/xfrm6_policy.c b/net/ipv6/xfrm6_policy.c
index cc07216..15aa4c5 100644
--- a/net/ipv6/xfrm6_policy.c
+++ b/net/ipv6/xfrm6_policy.c
@@ -375,7 +375,7 @@ static void xfrm6_dst_ifdown(struct dst_entry *dst, struct net_device *dev,
 
 	xdst = (struct xfrm_dst *)dst;
 	if (xdst->u.rt6.rt6i_idev->dev == dev) {
-		struct inet6_dev *loopback_idev = in6_dev_get(loopback_dev);
+		struct inet6_dev *loopback_idev = in6_dev_get(init_net.loopback_dev);
 		BUG_ON(!loopback_idev);
 
 		do {