mac80211: Suppress NEW_PEER_CANDIDATE event if no room

BugLink: http://bugs.launchpad.net/bugs/1744873

[ Upstream commit 11197d00 ]

Previously, kernel sends NEW_PEER_CANDIDATE event to user land even if
the found peer does not have any room to accept other peer. This causes
continuous connection trials.
Signed-off-by: Masashi Honma <masashi.honma@gmail.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>

net/mac80211/mesh_plink.c

@@ -495,12 +495,14 @@ mesh_sta_info_alloc(struct ieee80211_sub_if_data *sdata, u8 *addr,
 
 	/* Userspace handles station allocation */
 	if (sdata->u.mesh.user_mpm ||
-	    sdata->u.mesh.security & IEEE80211_MESH_SEC_AUTHED)
-		cfg80211_notify_new_peer_candidate(sdata->dev, addr,
-						   elems->ie_start,
-						   elems->total_len,
-						   GFP_KERNEL);
-	else
+	    sdata->u.mesh.security & IEEE80211_MESH_SEC_AUTHED) {
+		if (mesh_peer_accepts_plinks(elems) &&
+		    mesh_plink_availables(sdata))
+			cfg80211_notify_new_peer_candidate(sdata->dev, addr,
+							   elems->ie_start,
+							   elems->total_len,
+							   GFP_KERNEL);
+	} else
 		sta = __mesh_sta_info_alloc(sdata, addr);
 
 	return sta;