wifi: mt76: mt7996: grab mt76 mutex in mt7996_mac_sta_event()

[ Upstream commit 5a4bcba ]

Grab mt76 mutex in mt7996_mac_sta_event routine in order to rely on
mt76_dereference() utility macro.

Fixes: ecd72f9 ("wifi: mt76: mt7996: Support MLO in mt7996_mac_sta_event()")
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Tested-by: Ben Greear <greearb@candelatech.com>
Link: https://patch.msgid.link/20251114-mt76-fix-missing-mtx-v1-1-259ebf11f654@kernel.org
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Sasha Levin <sashal@kernel.org>

Author: LorenzoBianconi

drivers/net/wireless/mediatek/mt76/mt7996/main.c

@@ -1150,12 +1150,15 @@ mt7996_mac_sta_event(struct mt7996_dev *dev, struct ieee80211_vif *vif,
 	unsigned long links = sta->valid_links;
 	struct ieee80211_link_sta *link_sta;
 	unsigned int link_id;
+	int err = 0;
+
+	mutex_lock(&dev->mt76.mutex);
 
 	for_each_sta_active_link(vif, sta, link_sta, link_id) {
 		struct ieee80211_bss_conf *link_conf;
 		struct mt7996_sta_link *msta_link;
 		struct mt7996_vif_link *link;
-		int i, err;
+		int i;
 
 		link_conf = link_conf_dereference_protected(vif, link_id);
 		if (!link_conf)
@@ -1175,12 +1178,12 @@ mt7996_mac_sta_event(struct mt7996_dev *dev, struct ieee80211_vif *vif,
 						 link, msta_link,
 						 CONN_STATE_CONNECT, true);
 			if (err)
-				return err;
+				goto unlock;
 
 			err = mt7996_mcu_add_rate_ctrl(dev, msta_link->sta, vif,
 						       link_id, false);
 			if (err)
-				return err;
+				goto unlock;
 
 			msta_link->wcid.tx_info |= MT_WCID_TX_INFO_SET;
 			break;
@@ -1189,7 +1192,7 @@ mt7996_mac_sta_event(struct mt7996_dev *dev, struct ieee80211_vif *vif,
 						 link, msta_link,
 						 CONN_STATE_PORT_SECURE, false);
 			if (err)
-				return err;
+				goto unlock;
 			break;
 		case MT76_STA_EVENT_DISASSOC:
 			for (i = 0; i < ARRAY_SIZE(msta_link->twt.flow); i++)
@@ -1209,8 +1212,10 @@ mt7996_mac_sta_event(struct mt7996_dev *dev, struct ieee80211_vif *vif,
 			break;
 		}
 	}
+unlock:
+	mutex_unlock(&dev->mt76.mutex);
 
-	return 0;
+	return err;
 }
 
 static void