wifi: mac80211: fix queue selection for mesh/OCB interfaces

When using iTXQ, the code assumes that there is only one vif queue for
broadcast packets, using the BE queue. Allowing non-BE queue marking
violates that assumption and txq->ac == skb_queue_mapping is no longer
guaranteed. This can cause issues with queue handling in the driver and
also causes issues with the recent ATF change, resulting in an AQL
underflow warning.

Cc: stable@vger.kernel.org
Signed-off-by: NFelix Fietkau <nbd@nbd.name>
Link: https://lore.kernel.org/r/20220702145227.39356-1-nbd@nbd.nameSigned-off-by: NJohannes Berg <johannes.berg@intel.com>

net/mac80211/wme.c

@@ -147,8 +147,8 @@ u16 __ieee80211_select_queue(struct ieee80211_sub_if_data *sdata,
 	bool qos;
 
 	/* all mesh/ocb stations are required to support WME */
-	if (sdata->vif.type == NL80211_IFTYPE_MESH_POINT ||
-	    sdata->vif.type == NL80211_IFTYPE_OCB)
+	if (sta && (sdata->vif.type == NL80211_IFTYPE_MESH_POINT ||
+		    sdata->vif.type == NL80211_IFTYPE_OCB))
 		qos = true;
 	else if (sta)
 		qos = sta->sta.wme;