nl80211: send interface after creation

After a new virtual interface is created, reply
to userspace with a message detailing it so it
knows the new wdev identifier.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

net/wireless/nl80211.c

@@ -1972,6 +1972,7 @@ static int nl80211_new_interface(struct sk_buff *skb, struct genl_info *info)
 	struct cfg80211_registered_device *rdev = info->user_ptr[0];
 	struct vif_params params;
 	struct wireless_dev *wdev;
+	struct sk_buff *msg;
 	int err;
 	enum nl80211_iftype type = NL80211_IFTYPE_UNSPECIFIED;
 	u32 flags;
@@ -1998,14 +1999,20 @@ static int nl80211_new_interface(struct sk_buff *skb, struct genl_info *info)
 			return err;
 	}
 
+	msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
+	if (!msg)
+		return -ENOMEM;
+
 	err = parse_monitor_flags(type == NL80211_IFTYPE_MONITOR ?
 				  info->attrs[NL80211_ATTR_MNTR_FLAGS] : NULL,
 				  &flags);
 	wdev = rdev->ops->add_virtual_intf(&rdev->wiphy,
 		nla_data(info->attrs[NL80211_ATTR_IFNAME]),
 		type, err ? NULL : &flags, &params);
-	if (IS_ERR(wdev))
+	if (IS_ERR(wdev)) {
+		nlmsg_free(msg);
 		return PTR_ERR(wdev);
+	}
 
 	if (type == NL80211_IFTYPE_MESH_POINT &&
 	    info->attrs[NL80211_ATTR_MESH_ID]) {
@@ -2019,7 +2026,13 @@ static int nl80211_new_interface(struct sk_buff *skb, struct genl_info *info)
 		wdev_unlock(wdev);
 	}
 
-	return 0;
+	if (nl80211_send_iface(msg, info->snd_pid, info->snd_seq, 0,
+			       rdev, wdev) < 0) {
+		nlmsg_free(msg);
+		return -ENOBUFS;
+	}
+
+	return genlmsg_reply(msg, info);
 }
 
 static int nl80211_del_interface(struct sk_buff *skb, struct genl_info *info)