mac80211: Use a separate CCMP PN receive counter for management frames

When management frame protection (IEEE 802.11w) is used, we must use a
separate counter for tracking received CCMP packet number for the
management frames. The previously used NUM_RX_DATA_QUEUESth queue was
shared with data frames when QoS was not used and that can cause
problems in detecting replays incorrectly for robust management frames.
Add a new counter just for robust management frames to avoid this issue.

Signed-off-by: Jouni Malinen <jouni.malinen@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/net/mac80211/wpa.c b/net/mac80211/wpa.c
index 0adbcc9..a14e677 100644
--- a/net/mac80211/wpa.c
+++ b/net/mac80211/wpa.c
@@ -436,6 +436,7 @@
 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
 	u8 pn[CCMP_PN_LEN];
 	int data_len;
+	int queue;
 
 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
 
@@ -453,7 +454,10 @@
 
 	ccmp_hdr2pn(pn, skb->data + hdrlen);
 
-	if (memcmp(pn, key->u.ccmp.rx_pn[rx->queue], CCMP_PN_LEN) <= 0) {
+	queue = ieee80211_is_mgmt(hdr->frame_control) ?
+		NUM_RX_DATA_QUEUES : rx->queue;
+
+	if (memcmp(pn, key->u.ccmp.rx_pn[queue], CCMP_PN_LEN) <= 0) {
 		key->u.ccmp.replays++;
 		return RX_DROP_UNUSABLE;
 	}
@@ -470,7 +474,7 @@
 			return RX_DROP_UNUSABLE;
 	}
 
-	memcpy(key->u.ccmp.rx_pn[rx->queue], pn, CCMP_PN_LEN);
+	memcpy(key->u.ccmp.rx_pn[queue], pn, CCMP_PN_LEN);
 
 	/* Remove CCMP header and MIC */
 	skb_trim(skb, skb->len - CCMP_MIC_LEN);