mac80211: Report beacon protection failures to user space

Report received Beacon frames that do not have a valid MME MIC when
beacon protection is enabled. This covers both the cases of no MME in
the received frame and invalid MIC in the MME.
Signed-off-by: Jouni Malinen <jouni@codeaurora.org>
Link: https://lore.kernel.org/r/20200401142548.6990-2-jouni@codeaurora.orgSigned-off-by: Johannes Berg <johannes.berg@intel.com>

net/mac80211/rx.c

@@ -1984,8 +1984,12 @@ ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
 
 		if (mmie_keyidx < NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS ||
 		    mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS +
-		    NUM_DEFAULT_BEACON_KEYS)
+		    NUM_DEFAULT_BEACON_KEYS) {
+			cfg80211_rx_unprot_mlme_mgmt(rx->sdata->dev,
+						     skb->data,
+						     skb->len);
 			return RX_DROP_MONITOR; /* unexpected BIP keyidx */
+		}
 
 		rx->key = ieee80211_rx_get_bigtk(rx, mmie_keyidx);
 		if (!rx->key)
@@ -2131,6 +2135,10 @@ ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
 	/* either the frame has been decrypted or will be dropped */
 	status->flag |= RX_FLAG_DECRYPTED;
 
+	if (unlikely(ieee80211_is_beacon(fc) && result == RX_DROP_UNUSABLE))
+		cfg80211_rx_unprot_mlme_mgmt(rx->sdata->dev,
+					     skb->data, skb->len);
+
 	return result;
 }
 
@@ -2411,8 +2419,12 @@ static int ieee80211_drop_unencrypted_mgmt(struct ieee80211_rx_data *rx)
 			return -EACCES;
 		}
 		if (unlikely(ieee80211_is_beacon(fc) && rx->key &&
-			     ieee80211_get_mmie_keyidx(rx->skb) < 0))
+			     ieee80211_get_mmie_keyidx(rx->skb) < 0)) {
+			cfg80211_rx_unprot_mlme_mgmt(rx->sdata->dev,
+						     rx->skb->data,
+						     rx->skb->len);
 			return -EACCES;
+		}
 		/*
 		 * When using MFP, Action frames are not allowed prior to
 		 * having configured keys.