diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index 510a745..70b2af2 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -1005,6 +1005,9 @@
 	}
 
 	if (params->vlan && params->vlan != sta->sdata->dev) {
+		bool prev_4addr = false;
+		bool new_4addr = false;
+
 		vlansdata = IEEE80211_DEV_TO_SUB_IF(params->vlan);
 
 		if (vlansdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
@@ -1020,9 +1023,25 @@
 			}
 
 			rcu_assign_pointer(vlansdata->u.vlan.sta, sta);
+			new_4addr = true;
+		}
+
+		if (sta->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
+		    sta->sdata->u.vlan.sta) {
+			rcu_assign_pointer(sta->sdata->u.vlan.sta, NULL);
+			prev_4addr = true;
 		}
 
 		sta->sdata = vlansdata;
+
+		if (sta->sta_state == IEEE80211_STA_AUTHORIZED &&
+		    prev_4addr != new_4addr) {
+			if (new_4addr)
+				atomic_dec(&sta->sdata->bss->num_mcast_sta);
+			else
+				atomic_inc(&sta->sdata->bss->num_mcast_sta);
+		}
+
 		ieee80211_send_layer2_update(sta);
 	}