[NET]: Make the device list and device lookups per namespace.

This patch makes most of the generic device layer network
namespace safe.  This patch makes dev_base_head a
network namespace variable, and then it picks up
a few associated variables.  The functions:
dev_getbyhwaddr
dev_getfirsthwbytype
dev_get_by_flags
dev_get_by_name
__dev_get_by_name
dev_get_by_index
__dev_get_by_index
dev_ioctl
dev_ethtool
dev_load
wireless_process_ioctl

were modified to take a network namespace argument, and
deal with it.

vlan_ioctl_set and brioctl_set were modified so their
hooks will receive a network namespace argument.

So basically anthing in the core of the network stack that was
affected to by the change of dev_base was modified to handle
multiple network namespaces.  The rest of the network stack was
simply modified to explicitly use &init_net the initial network
namespace.  This can be fixed when those components of the network
stack are modified to handle multiple network namespaces.

For now the ifindex generator is left global.

Fundametally ifindex numbers are per namespace, or else
we will have corner case problems with migration when
we get that far.

At the same time there are assumptions in the network stack
that the ifindex of a network device won't change.  Making
the ifindex number global seems a good compromise until
the network stack can cope with ifindex changes when
you change namespaces, and the like.

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

1 files changed, 29 insertions, 9 deletions

diff --git a/net/wireless/wext.c b/net/wireless/wext.c
index b8069af..e8b3409 100644
--- a/net/wireless/wext.c
+++ b/net/wireless/wext.c
@@ -673,7 +673,22 @@ static const struct seq_operations wireless_seq_ops = {
 
 static int wireless_seq_open(struct inode *inode, struct file *file)
 {
-	return seq_open(file, &wireless_seq_ops);
+	struct seq_file *seq;
+	int res;
+	res = seq_open(file, &wireless_seq_ops);
+	if (!res) {
+		seq = file->private_data;
+		seq->private = get_net(PROC_NET(inode));
+	}
+	return res;
+}
+
+static int wireless_seq_release(struct inode *inode, struct file *file)
+{
+	struct seq_file *seq = file->private_data;
+	struct net *net = seq->private;
+	put_net(net);
+	return seq_release(inode, file);
 }
 
 static const struct file_operations wireless_seq_fops = {
@@ -681,17 +696,22 @@ static const struct file_operations wireless_seq_fops = {
 	.open    = wireless_seq_open,
 	.read    = seq_read,
 	.llseek  = seq_lseek,
-	.release = seq_release,
+	.release = wireless_seq_release,
 };
 
-int __init wext_proc_init(void)
+int wext_proc_init(struct net *net)
 {
 	/* Create /proc/net/wireless entry */
-	if (!proc_net_fops_create(&init_net, "wireless", S_IRUGO, &wireless_seq_fops))
+	if (!proc_net_fops_create(net, "wireless", S_IRUGO, &wireless_seq_fops))
 		return -ENOMEM;
 
 	return 0;
 }
+
+void wext_proc_exit(struct net *net)
+{
+	proc_net_remove(net, "wireless");
+}
 #endif	/* CONFIG_PROC_FS */
 
 /************************** IOCTL SUPPORT **************************/
@@ -1011,7 +1031,7 @@ static int ioctl_private_call(struct net_device *dev, struct ifreq *ifr,
  * Main IOCTl dispatcher.
  * Check the type of IOCTL and call the appropriate wrapper...
  */
-static int wireless_process_ioctl(struct ifreq *ifr, unsigned int cmd)
+static int wireless_process_ioctl(struct net *net, struct ifreq *ifr, unsigned int cmd)
 {
 	struct net_device *dev;
 	iw_handler	handler;
@@ -1020,7 +1040,7 @@ static int wireless_process_ioctl(struct ifreq *ifr, unsigned int cmd)
 	 * The copy_to/from_user() of ifr is also dealt with in there */
 
 	/* Make sure the device exist */
-	if ((dev = __dev_get_by_name(ifr->ifr_name)) == NULL)
+	if ((dev = __dev_get_by_name(net, ifr->ifr_name)) == NULL)
 		return -ENODEV;
 
 	/* A bunch of special cases, then the generic case...
@@ -1054,7 +1074,7 @@ static int wireless_process_ioctl(struct ifreq *ifr, unsigned int cmd)
 }
 
 /* entry point from dev ioctl */
-int wext_handle_ioctl(struct ifreq *ifr, unsigned int cmd,
+int wext_handle_ioctl(struct net *net, struct ifreq *ifr, unsigned int cmd,
 		      void __user *arg)
 {
 	int ret;
@@ -1066,9 +1086,9 @@ int wext_handle_ioctl(struct ifreq *ifr, unsigned int cmd,
 	    && !capable(CAP_NET_ADMIN))
 		return -EPERM;
 
-	dev_load(ifr->ifr_name);
+	dev_load(net, ifr->ifr_name);
 	rtnl_lock();
-	ret = wireless_process_ioctl(ifr, cmd);
+	ret = wireless_process_ioctl(net, ifr, cmd);
 	rtnl_unlock();
 	if (IW_IS_GET(cmd) && copy_to_user(arg, ifr, sizeof(struct ifreq)))
 		return -EFAULT;