mac80211: fix wme code

In commit e100bb6 (mac80211:
QoS related cleanups) I accidentally changed a variable from
int to u16 causing a warning that a comparison for < 0 was always
false. John thought this was a missing deletion of code and removed
the warning by deleting the never executed branch of code in commit
3df5ee6 (wireless: fix warning
introduced by "mac80211: QoS related cleanups") but the problem really
was my mistake of using a u16 variable for the queue variable when
that variable can also contain an error code. This patch restores
the original code and variable type.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

net/mac80211/wme.c

@@ -155,8 +155,7 @@ static int wme_qdiscop_enqueue(struct sk_buff *skb, struct Qdisc* qd)
 	unsigned short fc = le16_to_cpu(hdr->frame_control);
 	struct Qdisc *qdisc;
 	struct sta_info *sta;
-	int err;
-	u16 queue;
+	int err, queue;
 	u8 tid;
 
 	if (pkt_data->flags & IEEE80211_TXPD_REQUEUE) {
@@ -216,15 +215,20 @@ static int wme_qdiscop_enqueue(struct sk_buff *skb, struct Qdisc* qd)
 		rcu_read_unlock();
 	}
 
-	tid = skb->priority & QOS_CONTROL_TAG1D_MASK;
-	pkt_data->queue = (unsigned int) queue;
-	qdisc = q->queues[queue];
-	err = qdisc->enqueue(skb, qdisc);
-	if (err == NET_XMIT_SUCCESS) {
-		qd->q.qlen++;
-		qd->bstats.bytes += skb->len;
-		qd->bstats.packets++;
-		return NET_XMIT_SUCCESS;
+	if (unlikely(queue < 0)) {
+			kfree_skb(skb);
+			err = NET_XMIT_DROP;
+	} else {
+		tid = skb->priority & QOS_CONTROL_TAG1D_MASK;
+		pkt_data->queue = (unsigned int) queue;
+		qdisc = q->queues[queue];
+		err = qdisc->enqueue(skb, qdisc);
+		if (err == NET_XMIT_SUCCESS) {
+			qd->q.qlen++;
+			qd->bstats.bytes += skb->len;
+			qd->bstats.packets++;
+			return NET_XMIT_SUCCESS;
+		}
 	}
 	qd->qstats.drops++;
 	return err;