[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>

7 files changed, 55 insertions, 39 deletions

diff --git a/include/linux/if_bridge.h b/include/linux/if_bridge.h
index 4ff211d..99e3a1a 100644
--- a/include/linux/if_bridge.h
+++ b/include/linux/if_bridge.h
@@ -104,7 +104,7 @@ struct __fdb_entry
 
 #include <linux/netdevice.h>
 
-extern void brioctl_set(int (*ioctl_hook)(unsigned int, void __user *));
+extern void brioctl_set(int (*ioctl_hook)(struct net *, unsigned int, void __user *));
 extern struct sk_buff *(*br_handle_frame_hook)(struct net_bridge_port *p,
 					       struct sk_buff *skb);
 extern int (*br_should_route_hook)(struct sk_buff **pskb);
diff --git a/include/linux/if_vlan.h b/include/linux/if_vlan.h
index f8443fd..976d4b1 100644
--- a/include/linux/if_vlan.h
+++ b/include/linux/if_vlan.h
@@ -62,7 +62,7 @@ struct vlan_hdr {
 #define VLAN_VID_MASK	0xfff
 
 /* found in socket.c */
-extern void vlan_ioctl_set(int (*hook)(void __user *));
+extern void vlan_ioctl_set(int (*hook)(struct net *, void __user *));
 
 #define VLAN_NAME "vlan"
 
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index dc3c15b..7353b3e 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -741,44 +741,48 @@ struct packet_type {
 #include <linux/notifier.h>
 
 extern struct net_device		loopback_dev;		/* The loopback */
-extern struct list_head			dev_base_head;		/* All devices */
 extern rwlock_t				dev_base_lock;		/* Device list lock */
 
-#define for_each_netdev(d)		\
-		list_for_each_entry(d, &dev_base_head, dev_list)
-#define for_each_netdev_safe(d, n)	\
-		list_for_each_entry_safe(d, n, &dev_base_head, dev_list)
-#define for_each_netdev_continue(d)		\
-		list_for_each_entry_continue(d, &dev_base_head, dev_list)
-#define net_device_entry(lh)	list_entry(lh, struct net_device, dev_list)
-
-static inline struct net_device *next_net_device(struct net_device *dev)
-{
-	struct list_head *lh;
 
-	lh = dev->dev_list.next;
-	return lh == &dev_base_head ? NULL : net_device_entry(lh);
-}
+#define for_each_netdev(net, d)		\
+		list_for_each_entry(d, &(net)->dev_base_head, dev_list)
+#define for_each_netdev_safe(net, d, n)	\
+		list_for_each_entry_safe(d, n, &(net)->dev_base_head, dev_list)
+#define for_each_netdev_continue(net, d)		\
+		list_for_each_entry_continue(d, &(net)->dev_base_head, dev_list)
+#define net_device_entry(lh)	list_entry(lh, struct net_device, dev_list)
 
-static inline struct net_device *first_net_device(void)
-{
-	return list_empty(&dev_base_head) ? NULL :
-		net_device_entry(dev_base_head.next);
-}
+#define next_net_device(d) 						\
+({									\
+	struct net_device *dev = d;					\
+	struct list_head *lh;						\
+	struct net *net;						\
+									\
+	net = dev->nd_net;						\
+	lh = dev->dev_list.next;					\
+	lh == &net->dev_base_head ? NULL : net_device_entry(lh);	\
+})
+
+#define first_net_device(N)					\
+({								\
+	struct net *NET = (N);					\
+	list_empty(&NET->dev_base_head) ? NULL :		\
+		net_device_entry(NET->dev_base_head.next);	\
+})
 
 extern int 			netdev_boot_setup_check(struct net_device *dev);
 extern unsigned long		netdev_boot_base(const char *prefix, int unit);
-extern struct net_device    *dev_getbyhwaddr(unsigned short type, char *hwaddr);
-extern struct net_device *dev_getfirstbyhwtype(unsigned short type);
-extern struct net_device *__dev_getfirstbyhwtype(unsigned short type);
+extern struct net_device    *dev_getbyhwaddr(struct net *net, unsigned short type, char *hwaddr);
+extern struct net_device *dev_getfirstbyhwtype(struct net *net, unsigned short type);
+extern struct net_device *__dev_getfirstbyhwtype(struct net *net, unsigned short type);
 extern void		dev_add_pack(struct packet_type *pt);
 extern void		dev_remove_pack(struct packet_type *pt);
 extern void		__dev_remove_pack(struct packet_type *pt);
 
-extern struct net_device	*dev_get_by_flags(unsigned short flags,
+extern struct net_device	*dev_get_by_flags(struct net *net, unsigned short flags,
 						  unsigned short mask);
-extern struct net_device	*dev_get_by_name(const char *name);
-extern struct net_device	*__dev_get_by_name(const char *name);
+extern struct net_device	*dev_get_by_name(struct net *net, const char *name);
+extern struct net_device	*__dev_get_by_name(struct net *net, const char *name);
 extern int		dev_alloc_name(struct net_device *dev, const char *name);
 extern int		dev_open(struct net_device *dev);
 extern int		dev_close(struct net_device *dev);
@@ -790,8 +794,8 @@ extern void		synchronize_net(void);
 extern int 		register_netdevice_notifier(struct notifier_block *nb);
 extern int		unregister_netdevice_notifier(struct notifier_block *nb);
 extern int		call_netdevice_notifiers(unsigned long val, void *v);
-extern struct net_device	*dev_get_by_index(int ifindex);
-extern struct net_device	*__dev_get_by_index(int ifindex);
+extern struct net_device	*dev_get_by_index(struct net *net, int ifindex);
+extern struct net_device	*__dev_get_by_index(struct net *net, int ifindex);
 extern int		dev_restart(struct net_device *dev);
 #ifdef CONFIG_NETPOLL_TRAP
 extern int		netpoll_trap(void);
@@ -1007,8 +1011,8 @@ extern int		netif_rx_ni(struct sk_buff *skb);
 #define HAVE_NETIF_RECEIVE_SKB 1
 extern int		netif_receive_skb(struct sk_buff *skb);
 extern int		dev_valid_name(const char *name);
-extern int		dev_ioctl(unsigned int cmd, void __user *);
-extern int		dev_ethtool(struct ifreq *);
+extern int		dev_ioctl(struct net *net, unsigned int cmd, void __user *);
+extern int		dev_ethtool(struct net *net, struct ifreq *);
 extern unsigned		dev_get_flags(const struct net_device *);
 extern int		dev_change_flags(struct net_device *, unsigned);
 extern int		dev_change_name(struct net_device *, char *);
@@ -1327,7 +1331,7 @@ extern void		dev_set_allmulti(struct net_device *dev, int inc);
 extern void		netdev_state_change(struct net_device *dev);
 extern void		netdev_features_change(struct net_device *dev);
 /* Load a device via the kmod */
-extern void		dev_load(const char *name);
+extern void		dev_load(struct net *net, const char *name);
 extern void		dev_mcast_init(void);
 extern int		netdev_max_backlog;
 extern int		weight_p;
diff --git a/include/net/net_namespace.h b/include/net/net_namespace.h
index 5472476..fac42db 100644
--- a/include/net/net_namespace.h
+++ b/include/net/net_namespace.h
@@ -22,6 +22,10 @@ struct net {
 	struct proc_dir_entry 	*proc_net;
 	struct proc_dir_entry 	*proc_net_stat;
 	struct proc_dir_entry 	*proc_net_root;
+
+	struct list_head 	dev_base_head;
+	struct hlist_head 	*dev_name_head;
+	struct hlist_head	*dev_index_head;
 };
 
 extern struct net init_net;
diff --git a/include/net/pkt_cls.h b/include/net/pkt_cls.h
index 7968b1d..f285de6 100644
--- a/include/net/pkt_cls.h
+++ b/include/net/pkt_cls.h
@@ -2,6 +2,7 @@
 #define __NET_PKT_CLS_H
 
 #include <linux/pkt_cls.h>
+#include <net/net_namespace.h>
 #include <net/sch_generic.h>
 #include <net/act_api.h>
 
@@ -351,7 +352,7 @@ tcf_match_indev(struct sk_buff *skb, char *indev)
 	if (indev[0]) {
 		if  (!skb->iif)
 			return 0;
-		dev = __dev_get_by_index(skb->iif);
+		dev = __dev_get_by_index(&init_net, skb->iif);
 		if (!dev || strcmp(indev, dev->name))
 			return 0;
 	}
diff --git a/include/net/rtnetlink.h b/include/net/rtnetlink.h
index 8218288..793863e 100644
--- a/include/net/rtnetlink.h
+++ b/include/net/rtnetlink.h
@@ -78,7 +78,7 @@ extern void	__rtnl_link_unregister(struct rtnl_link_ops *ops);
 extern int	rtnl_link_register(struct rtnl_link_ops *ops);
 extern void	rtnl_link_unregister(struct rtnl_link_ops *ops);
 
-extern struct net_device *rtnl_create_link(char *ifname,
+extern struct net_device *rtnl_create_link(struct net *net, char *ifname,
 		const struct rtnl_link_ops *ops, struct nlattr *tb[]);
 extern const struct nla_policy ifla_policy[IFLA_MAX+1];
 
diff --git a/include/net/wext.h b/include/net/wext.h
index c02b8de..80b31d8 100644
--- a/include/net/wext.h
+++ b/include/net/wext.h
@@ -5,16 +5,23 @@
  * wireless extensions interface to the core code
  */
 
+struct net;
+
 #ifdef CONFIG_WIRELESS_EXT
-extern int wext_proc_init(void);
-extern int wext_handle_ioctl(struct ifreq *ifr, unsigned int cmd,
+extern int wext_proc_init(struct net *net);
+extern void wext_proc_exit(struct net *net);
+extern int wext_handle_ioctl(struct net *net, struct ifreq *ifr, unsigned int cmd,
 			     void __user *arg);
 #else
-static inline int wext_proc_init(void)
+static inline int wext_proc_init(struct net *net)
 {
 	return 0;
 }
-static inline int wext_handle_ioctl(struct ifreq *ifr, unsigned int cmd,
+static inline void wext_proc_exit(struct net *net)
+{
+	return;
+}
+static inline int wext_handle_ioctl(struct net *net, struct ifreq *ifr, unsigned int cmd,
 				    void __user *arg)
 {
 	return -EINVAL;