mac80211: fix broken use of VHT/20Mhz with some APs

commit "mac80211: disable 40MHz support in case of 20MHz AP"
broke working VHT in 20Mhz with APs like Netgear R6300v2 which
do not publish support for 40Mhz but allow use of VHT in 20Mhz.
The break is because VHT is disabled once no HT cap doesn't indicate
support for 40Mhz. This causes the assoc request to be sent without
any VHT IE and the association is only HT due to this.

For more details check out commit 4a817aa7
"mac80211: allow VHT with peers not capable of 40MHz"

Fixes: 53b954ee4a71 ("mac80211: disable 40MHz support in case of 20MHz AP")
Signed-off-by: Eyal Shapira <eyalx.shapira@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index 27231ac2dbdd7e2e85ead1eca1b7ffdbc82db6b8..f09bef7ac21d2fbeb555a412c3c55848a9e35f11 100644 (file)
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -173,7 +173,7 @@ ieee80211_determine_chantype(struct ieee80211_sub_if_data *sdata,
 
        if (!(ht_cap->cap_info &
              cpu_to_le16(IEEE80211_HT_CAP_SUP_WIDTH_20_40))) {
 
        if (!(ht_cap->cap_info &
              cpu_to_le16(IEEE80211_HT_CAP_SUP_WIDTH_20_40))) {

-               ret = IEEE80211_STA_DISABLE_40MHZ | IEEE80211_STA_DISABLE_VHT;
+               ret = IEEE80211_STA_DISABLE_40MHZ;

                goto out;
        }
 
                goto out;
        }