2 files changed, 48 insertions, 61 deletions

diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c
index b04a4378adcc..81241e18f3a4 100644
--- a/net/mac80211/rx.c
+++ b/net/mac80211/rx.c
@@ -2368,47 +2368,6 @@ ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx)
 	return RX_QUEUED;
 }
 
-static void ieee80211_rx_michael_mic_report(struct ieee80211_hdr *hdr,
-					    struct ieee80211_rx_data *rx)
-{
-	int keyidx;
-	unsigned int hdrlen;
-
-	hdrlen = ieee80211_hdrlen(hdr->frame_control);
-	if (rx->skb->len >= hdrlen + 4)
-		keyidx = rx->skb->data[hdrlen + 3] >> 6;
-	else
-		keyidx = -1;
-
-	if (!rx->sta) {
-		/*
-		 * Some hardware seem to generate incorrect Michael MIC
-		 * reports; ignore them to avoid triggering countermeasures.
-		 */
-		return;
-	}
-
-	if (!ieee80211_has_protected(hdr->frame_control))
-		return;
-
-	if (rx->sdata->vif.type == NL80211_IFTYPE_AP && keyidx) {
-		/*
-		 * APs with pairwise keys should never receive Michael MIC
-		 * errors for non-zero keyidx because these are reserved for
-		 * group keys and only the AP is sending real multicast
-		 * frames in the BSS.
-		 */
-		return;
-	}
-
-	if (!ieee80211_is_data(hdr->frame_control) &&
-	    !ieee80211_is_auth(hdr->frame_control))
-		return;
-
-	mac80211_ev_michael_mic_failure(rx->sdata, keyidx, hdr, NULL,
-					GFP_ATOMIC);
-}
-
 /* TODO: use IEEE80211_RX_FRAGMENTED */
 static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx,
 					struct ieee80211_rate *rate)
@@ -2752,12 +2711,6 @@ static bool ieee80211_prepare_and_rx_handle(struct ieee80211_rx_data *rx,
 	if (!prepares)
 		return false;
 
-	if (status->flag & RX_FLAG_MMIC_ERROR) {
-		if (status->rx_flags & IEEE80211_RX_RA_MATCH)
-			ieee80211_rx_michael_mic_report(hdr, rx);
-		return false;
-	}
-
 	if (!consume) {
 		skb = skb_copy(skb, GFP_ATOMIC);
 		if (!skb) {
diff --git a/net/mac80211/wpa.c b/net/mac80211/wpa.c
index f1765de2f4bf..9dc3b5f26e80 100644
--- a/net/mac80211/wpa.c
+++ b/net/mac80211/wpa.c
@@ -87,42 +87,76 @@ ieee80211_rx_h_michael_mic_verify(struct ieee80211_rx_data *rx)
 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 
-	/* No way to verify the MIC if the hardware stripped it */
-	if (status->flag & RX_FLAG_MMIC_STRIPPED)
+	/*
+	 * it makes no sense to check for MIC errors on anything other
+	 * than data frames.
+	 */
+	if (!ieee80211_is_data_present(hdr->frame_control))
+		return RX_CONTINUE;
+
+	/*
+	 * No way to verify the MIC if the hardware stripped it or
+	 * the IV with the key index. In this case we have solely rely
+	 * on the driver to set RX_FLAG_MMIC_ERROR in the event of a
+	 * MIC failure report.
+	 */
+	if (status->flag & (RX_FLAG_MMIC_STRIPPED | RX_FLAG_IV_STRIPPED)) {
+		if (status->flag & RX_FLAG_MMIC_ERROR)
+			goto mic_fail;
+
+		if (!(status->flag & RX_FLAG_IV_STRIPPED))
+			goto update_iv;
+
 		return RX_CONTINUE;
+	}
 
+	/*
+	 * Some hardware seems to generate Michael MIC failure reports; even
+	 * though, the frame was not encrypted with TKIP and therefore has no
+	 * MIC. Ignore the flag them to avoid triggering countermeasures.
+	 */
 	if (!rx->key || rx->key->conf.cipher != WLAN_CIPHER_SUITE_TKIP ||
-	    !ieee80211_has_protected(hdr->frame_control) ||
-	    !ieee80211_is_data_present(hdr->frame_control))
+	    !(status->flag & RX_FLAG_DECRYPTED))
 		return RX_CONTINUE;
 
+	if (rx->sdata->vif.type == NL80211_IFTYPE_AP && rx->key->conf.keyidx) {
+		/*
+		 * APs with pairwise keys should never receive Michael MIC
+		 * errors for non-zero keyidx because these are reserved for
+		 * group keys and only the AP is sending real multicast
+		 * frames in the BSS. (
+		 */
+		return RX_DROP_UNUSABLE;
+	}
+
+	if (status->flag & RX_FLAG_MMIC_ERROR)
+		goto mic_fail;
+
 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
 	if (skb->len < hdrlen + MICHAEL_MIC_LEN)
 		return RX_DROP_UNUSABLE;
 
 	data = skb->data + hdrlen;
 	data_len = skb->len - hdrlen - MICHAEL_MIC_LEN;
-
 	key = &rx->key->conf.key[NL80211_TKIP_DATA_OFFSET_RX_MIC_KEY];
 	michael_mic(key, hdr, data, data_len, mic);
-	if (memcmp(mic, data + data_len, MICHAEL_MIC_LEN) != 0) {
-		if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
-			return RX_DROP_UNUSABLE;
-
-		mac80211_ev_michael_mic_failure(rx->sdata, rx->key->conf.keyidx,
-						(void *) skb->data, NULL,
-						GFP_ATOMIC);
-		return RX_DROP_UNUSABLE;
-	}
+	if (memcmp(mic, data + data_len, MICHAEL_MIC_LEN) != 0)
+		goto mic_fail;
 
 	/* remove Michael MIC from payload */
 	skb_trim(skb, skb->len - MICHAEL_MIC_LEN);
 
+update_iv:
 	/* update IV in key information to be able to detect replays */
 	rx->key->u.tkip.rx[rx->queue].iv32 = rx->tkip_iv32;
 	rx->key->u.tkip.rx[rx->queue].iv16 = rx->tkip_iv16;
 
 	return RX_CONTINUE;
+
+mic_fail:
+	mac80211_ev_michael_mic_failure(rx->sdata, rx->key->conf.keyidx,
+					(void *) skb->data, NULL, GFP_ATOMIC);
+	return RX_DROP_UNUSABLE;
 }