mac80211: simplify zero address checks

The libertas_tf special code for zero addresses
is a bit too complex, it compares against a stack
value instead of using is_zero_ether_addr() and
tries to update all interfaces even if just the
one that's being brought up needs to be changed.
Additionally, the repeated check for a valid MAC
address need only be done if we actually changed
it on the fly.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

diff --git a/net/mac80211/iface.c b/net/mac80211/iface.c
index cc1c68d7dda61573d016db6348c4ca40e13382c2..ea50732ec5268cad89f2bd796f33ebc2de2e7f76 100644 (file)
--- a/net/mac80211/iface.c
+++ b/net/mac80211/iface.c
@@ -103,10 +103,9 @@ static int ieee80211_open(struct net_device *dev)
        u32 changed = 0;
        int res;
        u32 hw_reconf_flags = 0;
-       u8 null_addr[ETH_ALEN] = {0};
 
        /* fail early if user set an invalid address */
-       if (compare_ether_addr(dev->dev_addr, null_addr) &&
+       if (!is_zero_ether_addr(dev->dev_addr) &&
            !is_valid_ether_addr(dev->dev_addr))
                return -EADDRNOTAVAIL;
 
@@ -195,33 +194,22 @@ static int ieee80211_open(struct net_device *dev)
        }
 
        /*
-        * Check all interfaces and copy the hopefully now-present
-        * MAC address to those that have the special null one.
+        * Copy the hopefully now-present MAC address to
+        * this interface, if it has the special null one.
         */
-       list_for_each_entry(nsdata, &local->interfaces, list) {
-               struct net_device *ndev = nsdata->dev;
-
-               /*
-                * No need to check running since we do not allow
-                * it to start up with this invalid address.
-                */
-               if (compare_ether_addr(null_addr, ndev->dev_addr) == 0) {
-                       memcpy(ndev->dev_addr,
-                              local->hw.wiphy->perm_addr,
-                              ETH_ALEN);
-                       memcpy(ndev->perm_addr, ndev->dev_addr, ETH_ALEN);
+       if (is_zero_ether_addr(dev->dev_addr)) {
+               memcpy(dev->dev_addr,
+                      local->hw.wiphy->perm_addr,
+                      ETH_ALEN);
+               memcpy(dev->perm_addr, dev->dev_addr, ETH_ALEN);
+
+               if (!is_valid_ether_addr(dev->dev_addr)) {
+                       if (!local->open_count)
+                               drv_stop(local);
+                       return -EADDRNOTAVAIL;
                }
        }
 
-       /*
-        * Validate the MAC address for this device.
-        */
-       if (!is_valid_ether_addr(dev->dev_addr)) {
-               if (!local->open_count)
-                       drv_stop(local);
-               return -EADDRNOTAVAIL;
-       }
-
        switch (sdata->vif.type) {
        case NL80211_IFTYPE_AP_VLAN:
                /* no need to tell driver */