1 files changed, 114 insertions, 2 deletions

diff --git a/net/mac80211/iface.c b/net/mac80211/iface.c
index 0793d7a8d743..d5571b9420cd 100644
--- a/net/mac80211/iface.c
+++ b/net/mac80211/iface.c
@@ -815,6 +815,118 @@ int ieee80211_if_change_type(struct ieee80211_sub_if_data *sdata,
 	return 0;
 }
 
+static void ieee80211_assign_perm_addr(struct ieee80211_local *local,
+				       struct net_device *dev,
+				       enum nl80211_iftype type)
+{
+	struct ieee80211_sub_if_data *sdata;
+	u64 mask, start, addr, val, inc;
+	u8 *m;
+	u8 tmp_addr[ETH_ALEN];
+	int i;
+
+	/* default ... something at least */
+	memcpy(dev->perm_addr, local->hw.wiphy->perm_addr, ETH_ALEN);
+
+	if (is_zero_ether_addr(local->hw.wiphy->addr_mask) &&
+	    local->hw.wiphy->n_addresses <= 1)
+		return;
+
+
+	mutex_lock(&local->iflist_mtx);
+
+	switch (type) {
+	case NL80211_IFTYPE_MONITOR:
+		/* doesn't matter */
+		break;
+	case NL80211_IFTYPE_WDS:
+	case NL80211_IFTYPE_AP_VLAN:
+		/* match up with an AP interface */
+		list_for_each_entry(sdata, &local->interfaces, list) {
+			if (sdata->vif.type != NL80211_IFTYPE_AP)
+				continue;
+			memcpy(dev->perm_addr, sdata->vif.addr, ETH_ALEN);
+			break;
+		}
+		/* keep default if no AP interface present */
+		break;
+	default:
+		/* assign a new address if possible -- try n_addresses first */
+		for (i = 0; i < local->hw.wiphy->n_addresses; i++) {
+			bool used = false;
+
+			list_for_each_entry(sdata, &local->interfaces, list) {
+				if (memcmp(local->hw.wiphy->addresses[i].addr,
+					   sdata->vif.addr, ETH_ALEN) == 0) {
+					used = true;
+					break;
+				}
+			}
+
+			if (!used) {
+				memcpy(dev->perm_addr,
+				       local->hw.wiphy->addresses[i].addr,
+				       ETH_ALEN);
+				break;
+			}
+		}
+
+		/* try mask if available */
+		if (is_zero_ether_addr(local->hw.wiphy->addr_mask))
+			break;
+
+		m = local->hw.wiphy->addr_mask;
+		mask =	((u64)m[0] << 5*8) | ((u64)m[1] << 4*8) |
+			((u64)m[2] << 3*8) | ((u64)m[3] << 2*8) |
+			((u64)m[4] << 1*8) | ((u64)m[5] << 0*8);
+
+		if (__ffs64(mask) + hweight64(mask) != fls64(mask)) {
+			/* not a contiguous mask ... not handled now! */
+			printk(KERN_DEBUG "not contiguous\n");
+			break;
+		}
+
+		m = local->hw.wiphy->perm_addr;
+		start = ((u64)m[0] << 5*8) | ((u64)m[1] << 4*8) |
+			((u64)m[2] << 3*8) | ((u64)m[3] << 2*8) |
+			((u64)m[4] << 1*8) | ((u64)m[5] << 0*8);
+
+		inc = 1ULL<<__ffs64(mask);
+		val = (start & mask);
+		addr = (start & ~mask) | (val & mask);
+		do {
+			bool used = false;
+
+			tmp_addr[5] = addr >> 0*8;
+			tmp_addr[4] = addr >> 1*8;
+			tmp_addr[3] = addr >> 2*8;
+			tmp_addr[2] = addr >> 3*8;
+			tmp_addr[1] = addr >> 4*8;
+			tmp_addr[0] = addr >> 5*8;
+
+			val += inc;
+
+			list_for_each_entry(sdata, &local->interfaces, list) {
+				if (memcmp(tmp_addr, sdata->vif.addr,
+							ETH_ALEN) == 0) {
+					used = true;
+					break;
+				}
+			}
+
+			if (!used) {
+				memcpy(dev->perm_addr, tmp_addr, ETH_ALEN);
+				break;
+			}
+			addr = (start & ~mask) | (val & mask);
+		} while (addr != start);
+
+		break;
+	}
+
+	mutex_unlock(&local->iflist_mtx);
+}
+
 int ieee80211_if_add(struct ieee80211_local *local, const char *name,
 		     struct net_device **new_dev, enum nl80211_iftype type,
 		     struct vif_params *params)
@@ -844,8 +956,8 @@ int ieee80211_if_add(struct ieee80211_local *local, const char *name,
 	if (ret < 0)
 		goto fail;
 
-	memcpy(ndev->dev_addr, local->hw.wiphy->perm_addr, ETH_ALEN);
-	memcpy(ndev->perm_addr, ndev->dev_addr, ETH_ALEN);
+	ieee80211_assign_perm_addr(local, ndev, type);
+	memcpy(ndev->dev_addr, ndev->perm_addr, ETH_ALEN);
 	SET_NETDEV_DEV(ndev, wiphy_dev(local->hw.wiphy));
 
 	/* don't use IEEE80211_DEV_TO_SUB_IF because it checks too much */