nl80211: Add SOCKET_OWNER support to JOIN_IBSS

Signed-off-by: Denis Kenzior <denkenz@gmail.com>
[johannes: fix race with wdev lock/unlock by just acquiring once]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

include/uapi/linux/nl80211.h

@@ -1962,6 +1962,8 @@ enum nl80211_commands {
  *	multicast group.
  *	If set during %NL80211_CMD_ASSOCIATE or %NL80211_CMD_CONNECT the
  *	station will deauthenticate when the socket is closed.
+ *	If set during %NL80211_CMD_JOIN_IBSS the IBSS will be automatically
+ *	torn down when the socket is closed.
  *
  * @NL80211_ATTR_TDLS_INITIATOR: flag attribute indicating the current end is
  *	the TDLS link initiator.

net/wireless/core.h

@@ -282,7 +282,7 @@ void cfg80211_bss_age(struct cfg80211_registered_device *rdev,
                       unsigned long age_secs);
 
 /* IBSS */
-int cfg80211_join_ibss(struct cfg80211_registered_device *rdev,
+int __cfg80211_join_ibss(struct cfg80211_registered_device *rdev,
 			 struct net_device *dev,
 			 struct cfg80211_ibss_params *params,
 			 struct cfg80211_cached_keys *connkeys);

net/wireless/ibss.c

@@ -84,7 +84,7 @@ void cfg80211_ibss_joined(struct net_device *dev, const u8 *bssid,
 }
 EXPORT_SYMBOL(cfg80211_ibss_joined);
 
-static int __cfg80211_join_ibss(struct cfg80211_registered_device *rdev,
+int __cfg80211_join_ibss(struct cfg80211_registered_device *rdev,
 			 struct net_device *dev,
 			 struct cfg80211_ibss_params *params,
 			 struct cfg80211_cached_keys *connkeys)
@@ -92,6 +92,7 @@ static int __cfg80211_join_ibss(struct cfg80211_registered_device *rdev,
 	struct wireless_dev *wdev = dev->ieee80211_ptr;
 	int err;
 
+	ASSERT_RTNL();
 	ASSERT_WDEV_LOCK(wdev);
 
 	if (wdev->ssid_len)
@@ -146,23 +147,6 @@ static int __cfg80211_join_ibss(struct cfg80211_registered_device *rdev,
 	return 0;
 }
 
-int cfg80211_join_ibss(struct cfg80211_registered_device *rdev,
-		       struct net_device *dev,
-		       struct cfg80211_ibss_params *params,
-		       struct cfg80211_cached_keys *connkeys)
-{
-	struct wireless_dev *wdev = dev->ieee80211_ptr;
-	int err;
-
-	ASSERT_RTNL();
-
-	wdev_lock(wdev);
-	err = __cfg80211_join_ibss(rdev, dev, params, connkeys);
-	wdev_unlock(wdev);
-
-	return err;
-}
-
 static void __cfg80211_clear_ibss(struct net_device *dev, bool nowext)
 {
 	struct wireless_dev *wdev = dev->ieee80211_ptr;
@@ -224,6 +208,7 @@ int __cfg80211_leave_ibss(struct cfg80211_registered_device *rdev,
 	if (err)
 		return err;
 
+	wdev->conn_owner_nlportid = 0;
 	__cfg80211_clear_ibss(dev, nowext);
 
 	return 0;

net/wireless/nl80211.c

@@ -8679,9 +8679,14 @@ static int nl80211_join_ibss(struct sk_buff *skb, struct genl_info *info)
 	ibss.userspace_handles_dfs =
 		nla_get_flag(info->attrs[NL80211_ATTR_HANDLE_DFS]);
 
-	err = cfg80211_join_ibss(rdev, dev, &ibss, connkeys);
+	wdev_lock(dev->ieee80211_ptr);
+	err = __cfg80211_join_ibss(rdev, dev, &ibss, connkeys);
 	if (err)
 		kzfree(connkeys);
+	else if (info->attrs[NL80211_ATTR_SOCKET_OWNER])
+		dev->ieee80211_ptr->conn_owner_nlportid = info->snd_portid;
+	wdev_unlock(dev->ieee80211_ptr);
+
 	return err;
 }