mac80211: avoid using ext NSS high BW if not supported

If the AP advertises inconsistent data, namely it has CCFS1 or CCFS2,
but doesn't advertise support for 160/80+80 bandwidth or "Extended NSS
BW Support", then we cannot use any MCSes in the the higher bandwidth.
Thus, avoid connecting with higher bandwidth since it's less efficient
that way.

Link: https://lore.kernel.org/r/20200528213443.0e55d40c3ccc.I6fd0b4708ebd087e5e46466c3e91f6efbcbef668@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 19 insertions, 6 deletions

diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index f6ddce646f18..1f9c48414c85 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -145,6 +145,7 @@ static u32
 ieee80211_determine_chantype(struct ieee80211_sub_if_data *sdata,
 			     struct ieee80211_supported_band *sband,
 			     struct ieee80211_channel *channel,
+			     u32 vht_cap_info,
 			     const struct ieee80211_ht_operation *ht_oper,
 			     const struct ieee80211_vht_operation *vht_oper,
 			     const struct ieee80211_he_operation *he_oper,
@@ -223,7 +224,7 @@ ieee80211_determine_chantype(struct ieee80211_sub_if_data *sdata,
 		memcpy(&he_oper_vht_cap, he_oper->optional, 3);
 		he_oper_vht_cap.basic_mcs_set = cpu_to_le16(0);
 
-		if (!ieee80211_chandef_vht_oper(&sdata->local->hw,
+		if (!ieee80211_chandef_vht_oper(&sdata->local->hw, vht_cap_info,
 						&he_oper_vht_cap, ht_oper,
 						&vht_chandef)) {
 			if (!(ifmgd->flags & IEEE80211_STA_DISABLE_HE))
@@ -232,8 +233,10 @@ ieee80211_determine_chantype(struct ieee80211_sub_if_data *sdata,
 			ret = IEEE80211_STA_DISABLE_HE;
 			goto out;
 		}
-	} else if (!ieee80211_chandef_vht_oper(&sdata->local->hw, vht_oper,
-					       ht_oper, &vht_chandef)) {
+	} else if (!ieee80211_chandef_vht_oper(&sdata->local->hw,
+					       vht_cap_info,
+					       vht_oper, ht_oper,
+					       &vht_chandef)) {
 		if (!(ifmgd->flags & IEEE80211_STA_DISABLE_VHT))
 			sdata_info(sdata,
 				   "AP VHT information is invalid, disable VHT\n");
@@ -329,6 +332,7 @@ out:
 static int ieee80211_config_bw(struct ieee80211_sub_if_data *sdata,
 			       struct sta_info *sta,
 			       const struct ieee80211_ht_cap *ht_cap,
+			       const struct ieee80211_vht_cap *vht_cap,
 			       const struct ieee80211_ht_operation *ht_oper,
 			       const struct ieee80211_vht_operation *vht_oper,
 			       const struct ieee80211_he_operation *he_oper,
@@ -343,6 +347,7 @@ static int ieee80211_config_bw(struct ieee80211_sub_if_data *sdata,
 	u16 ht_opmode;
 	u32 flags;
 	enum ieee80211_sta_rx_bandwidth new_sta_bw;
+	u32 vht_cap_info = 0;
 	int ret;
 
 	/* if HT was/is disabled, don't track any bandwidth changes */
@@ -371,8 +376,11 @@ static int ieee80211_config_bw(struct ieee80211_sub_if_data *sdata,
 		sdata->vif.bss_conf.ht_operation_mode = ht_opmode;
 	}
 
+	if (vht_cap)
+		vht_cap_info = le32_to_cpu(vht_cap->vht_cap_info);
+
 	/* calculate new channel (type) based on HT/VHT/HE operation IEs */
-	flags = ieee80211_determine_chantype(sdata, sband, chan,
+	flags = ieee80211_determine_chantype(sdata, sband, chan, vht_cap_info,
 					     ht_oper, vht_oper, he_oper,
 					     &chandef, true);
 
@@ -1327,6 +1335,7 @@ ieee80211_sta_process_chanswitch(struct ieee80211_sub_if_data *sdata,
 	enum nl80211_band current_band;
 	struct ieee80211_csa_ie csa_ie;
 	struct ieee80211_channel_switch ch_switch;
+	struct ieee80211_bss *bss;
 	int res;
 
 	sdata_assert_lock(sdata);
@@ -1338,7 +1347,9 @@ ieee80211_sta_process_chanswitch(struct ieee80211_sub_if_data *sdata,
 		return;
 
 	current_band = cbss->channel->band;
+	bss = (void *)cbss->priv;
 	res = ieee80211_parse_ch_switch_ie(sdata, elems, current_band,
+					   bss->vht_cap_info,
 					   ifmgd->flags,
 					   ifmgd->associated->bssid, &csa_ie);
 
@@ -4097,8 +4108,8 @@ static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata,
 
 	changed |= ieee80211_recalc_twt_req(sdata, sta, &elems);
 
-	if (ieee80211_config_bw(sdata, sta,
-				elems.ht_cap_elem, elems.ht_operation,
+	if (ieee80211_config_bw(sdata, sta, elems.ht_cap_elem,
+				elems.vht_cap_elem, elems.ht_operation,
 				elems.vht_operation, elems.he_operation,
 				bssid, &changed)) {
 		mutex_unlock(&local->sta_mtx);
@@ -4815,6 +4826,7 @@ static int ieee80211_prep_channel(struct ieee80211_sub_if_data *sdata,
 	const struct ieee80211_he_operation *he_oper = NULL;
 	struct ieee80211_supported_band *sband;
 	struct cfg80211_chan_def chandef;
+	struct ieee80211_bss *bss = (void *)cbss->priv;
 	int ret;
 	u32 i;
 	bool have_80mhz;
@@ -4913,6 +4925,7 @@ static int ieee80211_prep_channel(struct ieee80211_sub_if_data *sdata,
 
 	ifmgd->flags |= ieee80211_determine_chantype(sdata, sband,
 						     cbss->channel,
+						     bss->vht_cap_info,
 						     ht_oper, vht_oper, he_oper,
 						     &chandef, false);