Merge tag 'mac80211-for-davem-2017-06-13' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211

Johannes Berg says:

====================
Some fixes:
 * Avi fixes some fallout from my mac80211 RX flags changes
 * Emmanuel fixes an issue with adhering to the spec, and
   an oversight in the SMPS management code
 * Jason's patch makes mac80211 use constant-time memory
   comparisons for message authentication, to avoid having
   potentially observable timing differences
 * my fix makes mac80211 set the basic rates bitmap before
   the channel so the next update to the driver has more
   consistent data - this required another rework patch to
   remove some useless 5/10 MHz code that can never be hit
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

net/mac80211/cfg.c

@@ -902,6 +902,8 @@ static int ieee80211_start_ap(struct wiphy *wiphy, struct net_device *dev,
 	default:
 		return -EINVAL;
 	}
+	sdata->u.ap.req_smps = sdata->smps_mode;
+
 	sdata->needed_rx_chains = sdata->local->rx_chains;
 
 	sdata->vif.bss_conf.beacon_int = params->beacon_interval;

net/mac80211/ieee80211_i.h

@@ -1531,7 +1531,7 @@ ieee80211_have_rx_timestamp(struct ieee80211_rx_status *status)
 		return true;
 	/* can't handle non-legacy preamble yet */
 	if (status->flag & RX_FLAG_MACTIME_PLCP_START &&
-	    status->encoding != RX_ENC_LEGACY)
+	    status->encoding == RX_ENC_LEGACY)
 		return true;
 	return false;
 }

net/mac80211/mlme.c

@@ -601,7 +601,7 @@ static void ieee80211_send_assoc(struct ieee80211_sub_if_data *sdata)
 	struct ieee80211_supported_band *sband;
 	struct ieee80211_chanctx_conf *chanctx_conf;
 	struct ieee80211_channel *chan;
-	u32 rate_flags, rates = 0;
+	u32 rates = 0;
 
 	sdata_assert_lock(sdata);
 
@@ -612,7 +612,6 @@ static void ieee80211_send_assoc(struct ieee80211_sub_if_data *sdata)
 		return;
 	}
 	chan = chanctx_conf->def.chan;
-	rate_flags = ieee80211_chandef_rate_flags(&chanctx_conf->def);
 	rcu_read_unlock();
 	sband = local->hw.wiphy->bands[chan->band];
 	shift = ieee80211_vif_get_shift(&sdata->vif);
@@ -636,9 +635,6 @@ static void ieee80211_send_assoc(struct ieee80211_sub_if_data *sdata)
 		 */
 		rates_len = 0;
 		for (i = 0; i < sband->n_bitrates; i++) {
-			if ((rate_flags & sband->bitrates[i].flags)
-			    != rate_flags)
-				continue;
 			rates |= BIT(i);
 			rates_len++;
 		}
@@ -2818,7 +2814,7 @@ static void ieee80211_get_rates(struct ieee80211_supported_band *sband,
 				u32 *rates, u32 *basic_rates,
 				bool *have_higher_than_11mbit,
 				int *min_rate, int *min_rate_index,
-				int shift, u32 rate_flags)
+				int shift)
 {
 	int i, j;
 
@@ -2846,8 +2842,6 @@ static void ieee80211_get_rates(struct ieee80211_supported_band *sband,
 			int brate;
 
 			br = &sband->bitrates[j];
-			if ((rate_flags & br->flags) != rate_flags)
-				continue;
 
 			brate = DIV_ROUND_UP(br->bitrate, (1 << shift) * 5);
 			if (brate == rate) {
@@ -4398,40 +4392,32 @@ static int ieee80211_prep_connection(struct ieee80211_sub_if_data *sdata,
 			return -ENOMEM;
 	}
 
-	if (new_sta || override) {
-		err = ieee80211_prep_channel(sdata, cbss);
-		if (err) {
-			if (new_sta)
-				sta_info_free(local, new_sta);
-			return -EINVAL;
-		}
-	}
-
+	/*
+	 * Set up the information for the new channel before setting the
+	 * new channel. We can't - completely race-free - change the basic
+	 * rates bitmap and the channel (sband) that it refers to, but if
+	 * we set it up before we at least avoid calling into the driver's
+	 * bss_info_changed() method with invalid information (since we do
+	 * call that from changing the channel - only for IDLE and perhaps
+	 * some others, but ...).
+	 *
+	 * So to avoid that, just set up all the new information before the
+	 * channel, but tell the driver to apply it only afterwards, since
+	 * it might need the new channel for that.
+	 */
 	if (new_sta) {
 		u32 rates = 0, basic_rates = 0;
 		bool have_higher_than_11mbit;
 		int min_rate = INT_MAX, min_rate_index = -1;
-		struct ieee80211_chanctx_conf *chanctx_conf;
 		const struct cfg80211_bss_ies *ies;
 		int shift = ieee80211_vif_get_shift(&sdata->vif);
-		u32 rate_flags;
-
-		rcu_read_lock();
-		chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
-		if (WARN_ON(!chanctx_conf)) {
-			rcu_read_unlock();
-			sta_info_free(local, new_sta);
-			return -EINVAL;
-		}
-		rate_flags = ieee80211_chandef_rate_flags(&chanctx_conf->def);
-		rcu_read_unlock();
 
 		ieee80211_get_rates(sband, bss->supp_rates,
 				    bss->supp_rates_len,
 				    &rates, &basic_rates,
 				    &have_higher_than_11mbit,
 				    &min_rate, &min_rate_index,
-				    shift, rate_flags);
+				    shift);
 
 		/*
 		 * This used to be a workaround for basic rates missing
@@ -4489,8 +4475,22 @@ static int ieee80211_prep_connection(struct ieee80211_sub_if_data *sdata,
 			sdata->vif.bss_conf.sync_dtim_count = 0;
 		}
 		rcu_read_unlock();
+	}
 
-		/* tell driver about BSSID, basic rates and timing */
+	if (new_sta || override) {
+		err = ieee80211_prep_channel(sdata, cbss);
+		if (err) {
+			if (new_sta)
+				sta_info_free(local, new_sta);
+			return -EINVAL;
+		}
+	}
+
+	if (new_sta) {
+		/*
+		 * tell driver about BSSID, basic rates and timing
+		 * this was set up above, before setting the channel
+		 */
 		ieee80211_bss_info_change_notify(sdata,
 			BSS_CHANGED_BSSID | BSS_CHANGED_BASIC_RATES |
 			BSS_CHANGED_BEACON_INT);

net/mac80211/rx.c

@@ -1613,12 +1613,16 @@ ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx)
 	 */
 	if (!ieee80211_hw_check(&sta->local->hw, AP_LINK_PS) &&
 	    !ieee80211_has_morefrags(hdr->frame_control) &&
+	    !ieee80211_is_back_req(hdr->frame_control) &&
 	    !(status->rx_flags & IEEE80211_RX_DEFERRED_RELEASE) &&
 	    (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
 	     rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN) &&
-	    /* PM bit is only checked in frames where it isn't reserved,
+	    /*
+	     * PM bit is only checked in frames where it isn't reserved,
 	     * in AP mode it's reserved in non-bufferable management frames
 	     * (cf. IEEE 802.11-2012 8.2.4.1.7 Power Management field)
+	     * BAR frames should be ignored as specified in
+	     * IEEE 802.11-2012 10.2.1.2.
 	     */
 	    (!ieee80211_is_mgmt(hdr->frame_control) ||
 	     ieee80211_is_bufferable_mmpdu(hdr->frame_control))) {

net/mac80211/wpa.c

@@ -17,6 +17,7 @@
 #include <asm/unaligned.h>
 #include <net/mac80211.h>
 #include <crypto/aes.h>
+#include <crypto/algapi.h>
 
 #include "ieee80211_i.h"
 #include "michael.h"
@@ -153,7 +154,7 @@ ieee80211_rx_h_michael_mic_verify(struct ieee80211_rx_data *rx)
 	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 (crypto_memneq(mic, data + data_len, MICHAEL_MIC_LEN))
 		goto mic_fail;
 
 	/* remove Michael MIC from payload */
@@ -1048,7 +1049,7 @@ ieee80211_crypto_aes_cmac_decrypt(struct ieee80211_rx_data *rx)
 		bip_aad(skb, aad);
 		ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad,
 				   skb->data + 24, skb->len - 24, mic);
-		if (memcmp(mic, mmie->mic, sizeof(mmie->mic)) != 0) {
+		if (crypto_memneq(mic, mmie->mic, sizeof(mmie->mic))) {
 			key->u.aes_cmac.icverrors++;
 			return RX_DROP_UNUSABLE;
 		}
@@ -1098,7 +1099,7 @@ ieee80211_crypto_aes_cmac_256_decrypt(struct ieee80211_rx_data *rx)
 		bip_aad(skb, aad);
 		ieee80211_aes_cmac_256(key->u.aes_cmac.tfm, aad,
 				       skb->data + 24, skb->len - 24, mic);
-		if (memcmp(mic, mmie->mic, sizeof(mmie->mic)) != 0) {
+		if (crypto_memneq(mic, mmie->mic, sizeof(mmie->mic))) {
 			key->u.aes_cmac.icverrors++;
 			return RX_DROP_UNUSABLE;
 		}
@@ -1202,7 +1203,7 @@ ieee80211_crypto_aes_gmac_decrypt(struct ieee80211_rx_data *rx)
 		if (ieee80211_aes_gmac(key->u.aes_gmac.tfm, aad, nonce,
 				       skb->data + 24, skb->len - 24,
 				       mic) < 0 ||
-		    memcmp(mic, mmie->mic, sizeof(mmie->mic)) != 0) {
+		    crypto_memneq(mic, mmie->mic, sizeof(mmie->mic))) {
 			key->u.aes_gmac.icverrors++;
 			return RX_DROP_UNUSABLE;
 		}