cfg80211: respect iface combinations when starting operation

devlist_mtx locking is changed to accomodate changes.

Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

net/wireless/core.c

@@ -990,7 +990,9 @@ static int cfg80211_netdev_notifier_call(struct notifier_block *nb,
 			return notifier_from_errno(-EOPNOTSUPP);
 		if (rfkill_blocked(rdev->rfkill))
 			return notifier_from_errno(-ERFKILL);
+		mutex_lock(&rdev->devlist_mtx);
 		ret = cfg80211_can_add_interface(rdev, wdev->iftype);
+		mutex_unlock(&rdev->devlist_mtx);
 		if (ret)
 			return notifier_from_errno(ret);
 		cfg80211_lock_rdev(rdev);

net/wireless/ibss.c

@@ -118,6 +118,16 @@ int __cfg80211_join_ibss(struct cfg80211_registered_device *rdev,
 	wdev->wext.ibss.channel = params->channel;
 #endif
 	wdev->sme_state = CFG80211_SME_CONNECTING;
+
+	err = cfg80211_can_use_chan(rdev, wdev, params->channel,
+				    params->channel_fixed
+				    ? CHAN_MODE_SHARED
+				    : CHAN_MODE_EXCLUSIVE);
+	if (err) {
+		wdev->connect_keys = NULL;
+		return err;
+	}
+
 	err = rdev->ops->join_ibss(&rdev->wiphy, dev, params);
 	if (err) {
 		wdev->connect_keys = NULL;

net/wireless/mesh.c

@@ -155,6 +155,11 @@ int __cfg80211_join_mesh(struct cfg80211_registered_device *rdev,
 					  setup->channel_type))
 		return -EINVAL;
 
+	err = cfg80211_can_use_chan(rdev, wdev, setup->channel,
+				    CHAN_MODE_SHARED);
+	if (err)
+		return err;
+
 	err = rdev->ops->join_mesh(&rdev->wiphy, dev, conf, setup);
 	if (!err) {
 		memcpy(wdev->ssid, setup->mesh_id, setup->mesh_id_len);
@@ -173,9 +178,11 @@ int cfg80211_join_mesh(struct cfg80211_registered_device *rdev,
 	struct wireless_dev *wdev = dev->ieee80211_ptr;
 	int err;
 
+	mutex_lock(&rdev->devlist_mtx);
 	wdev_lock(wdev);
 	err = __cfg80211_join_mesh(rdev, dev, setup, conf);
 	wdev_unlock(wdev);
+	mutex_unlock(&rdev->devlist_mtx);
 
 	return err;
 }
@@ -208,6 +215,11 @@ int cfg80211_set_mesh_freq(struct cfg80211_registered_device *rdev,
 		if (!netif_running(wdev->netdev))
 			return -ENETDOWN;
 
+		err = cfg80211_can_use_chan(rdev, wdev, channel,
+					    CHAN_MODE_SHARED);
+		if (err)
+			return err;
+
 		err = rdev->ops->libertas_set_mesh_channel(&rdev->wiphy,
 							   wdev->netdev,
 							   channel);

net/wireless/mlme.c

@@ -302,8 +302,14 @@ int __cfg80211_mlme_auth(struct cfg80211_registered_device *rdev,
 	if (!req.bss)
 		return -ENOENT;
 
+	err = cfg80211_can_use_chan(rdev, wdev, req.bss->channel,
+				    CHAN_MODE_SHARED);
+	if (err)
+		goto out;
+
 	err = rdev->ops->auth(&rdev->wiphy, dev, &req);
 
+out:
 	cfg80211_put_bss(req.bss);
 	return err;
 }
@@ -317,11 +323,13 @@ int cfg80211_mlme_auth(struct cfg80211_registered_device *rdev,
 {
 	int err;
 
+	mutex_lock(&rdev->devlist_mtx);
 	wdev_lock(dev->ieee80211_ptr);
 	err = __cfg80211_mlme_auth(rdev, dev, chan, auth_type, bssid,
 				   ssid, ssid_len, ie, ie_len,
 				   key, key_len, key_idx);
 	wdev_unlock(dev->ieee80211_ptr);
+	mutex_unlock(&rdev->devlist_mtx);
 
 	return err;
 }
@@ -397,8 +405,14 @@ int __cfg80211_mlme_assoc(struct cfg80211_registered_device *rdev,
 		return -ENOENT;
 	}
 
+	err = cfg80211_can_use_chan(rdev, wdev, req.bss->channel,
+				    CHAN_MODE_SHARED);
+	if (err)
+		goto out;
+
 	err = rdev->ops->assoc(&rdev->wiphy, dev, &req);
 
+out:
 	if (err) {
 		if (was_connected)
 			wdev->sme_state = CFG80211_SME_CONNECTED;
@@ -421,11 +435,13 @@ int cfg80211_mlme_assoc(struct cfg80211_registered_device *rdev,
 	struct wireless_dev *wdev = dev->ieee80211_ptr;
 	int err;
 
+	mutex_lock(&rdev->devlist_mtx);
 	wdev_lock(wdev);
 	err = __cfg80211_mlme_assoc(rdev, dev, chan, bssid, prev_bssid,
 				    ssid, ssid_len, ie, ie_len, use_mfp, crypt,
 				    assoc_flags, ht_capa, ht_capa_mask);
 	wdev_unlock(wdev);
+	mutex_unlock(&rdev->devlist_mtx);
 
 	return err;
 }

net/wireless/nl80211.c

@@ -2478,6 +2478,14 @@ static int nl80211_start_ap(struct sk_buff *skb, struct genl_info *info)
 					  params.channel_type))
 		return -EINVAL;
 
+	mutex_lock(&rdev->devlist_mtx);
+	err = cfg80211_can_use_chan(rdev, wdev, params.channel,
+				    CHAN_MODE_SHARED);
+	mutex_unlock(&rdev->devlist_mtx);
+
+	if (err)
+		return err;
+
 	err = rdev->ops->start_ap(&rdev->wiphy, dev, &params);
 	if (!err) {
 		wdev->preset_chan = params.channel;

net/wireless/util.c

@@ -805,8 +805,10 @@ int cfg80211_change_iface(struct cfg80211_registered_device *rdev,
 		return -EBUSY;
 
 	if (ntype != otype && netif_running(dev)) {
+		mutex_lock(&rdev->devlist_mtx);
 		err = cfg80211_can_change_interface(rdev, dev->ieee80211_ptr,
 						    ntype);
+		mutex_unlock(&rdev->devlist_mtx);
 		if (err)
 			return err;
 
@@ -956,6 +958,7 @@ int cfg80211_can_use_iftype_chan(struct cfg80211_registered_device *rdev,
 	int i, j;
 
 	ASSERT_RTNL();
+	lockdep_assert_held(&rdev->devlist_mtx);
 
 	/* Always allow software iftypes */
 	if (rdev->wiphy.software_iftypes & BIT(iftype))
@@ -979,7 +982,6 @@ int cfg80211_can_use_iftype_chan(struct cfg80211_registered_device *rdev,
 		break;
 	}
 
-	mutex_lock(&rdev->devlist_mtx);
 	list_for_each_entry(wdev_iter, &rdev->netdev_list, list) {
 		if (wdev_iter == wdev)
 			continue;
@@ -999,10 +1001,8 @@ int cfg80211_can_use_iftype_chan(struct cfg80211_registered_device *rdev,
 				if (!used_channels[i] || used_channels[i] == ch)
 					break;
 
-			if (i == CFG80211_MAX_NUM_DIFFERENT_CHANNELS) {
-				mutex_unlock(&rdev->devlist_mtx);
+			if (i == CFG80211_MAX_NUM_DIFFERENT_CHANNELS)
 				return -EBUSY;
-			}
 
 			if (used_channels[i] == NULL) {
 				used_channels[i] = ch;
@@ -1018,7 +1018,6 @@ int cfg80211_can_use_iftype_chan(struct cfg80211_registered_device *rdev,
 		total++;
 		used_iftypes |= BIT(wdev_iter->iftype);
 	}
-	mutex_unlock(&rdev->devlist_mtx);
 
 	if (total == 1)
 		return 0;