[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, 5 insertions, 4 deletions

diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index b65ff653624..9e952e37b7d 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -17,6 +17,7 @@
 #include <linux/skbuff.h>
 #include <linux/etherdevice.h>
 #include <linux/bitmap.h>
+#include <net/net_namespace.h>
 #include <net/ieee80211_radiotap.h>
 #include <net/cfg80211.h>
 #include <net/mac80211.h>
@@ -1018,7 +1019,7 @@ static int inline ieee80211_tx_prepare(struct ieee80211_txrx_data *tx,
         struct net_device *dev;
 
         pkt_data = (struct ieee80211_tx_packet_data *)skb->cb;
-        dev = dev_get_by_index(pkt_data->ifindex);
+        dev = dev_get_by_index(&init_net, pkt_data->ifindex);
         if (unlikely(dev && !is_ieee80211_device(dev, mdev))) {
                 dev_put(dev);
                 dev = NULL;
@@ -1226,7 +1227,7 @@ int ieee80211_master_start_xmit(struct sk_buff *skb,
         memset(&control, 0, sizeof(struct ieee80211_tx_control));
 
         if (pkt_data->ifindex)
-                odev = dev_get_by_index(pkt_data->ifindex);
+                odev = dev_get_by_index(&init_net, pkt_data->ifindex);
         if (unlikely(odev && !is_ieee80211_device(odev, dev))) {
                 dev_put(odev);
                 odev = NULL;
@@ -1722,7 +1723,7 @@ struct sk_buff *ieee80211_beacon_get(struct ieee80211_hw *hw, int if_id,
         u8 *b_head, *b_tail;
         int bh_len, bt_len;
 
-        bdev = dev_get_by_index(if_id);
+        bdev = dev_get_by_index(&init_net, if_id);
         if (bdev) {
                 sdata = IEEE80211_DEV_TO_SUB_IF(bdev);
                 ap = &sdata->u.ap;
@@ -1836,7 +1837,7 @@ ieee80211_get_buffered_bc(struct ieee80211_hw *hw, int if_id,
         struct ieee80211_sub_if_data *sdata;
         struct ieee80211_if_ap *bss = NULL;
 
-        bdev = dev_get_by_index(if_id);
+        bdev = dev_get_by_index(&init_net, if_id);
         if (bdev) {
                 sdata = IEEE80211_DEV_TO_SUB_IF(bdev);
                 bss = &sdata->u.ap;