commit 496fcc294daab18799e190c0264863d653588d1f
author Johannes Berg <johannes.berg@intel.com> Thu Mar 12 08:53:27 2015 +0200
committer Johannes Berg <johannes.berg@intel.com> Mon Mar 16 09:36:11 2015 +0100
tree 0dba31906f61953699ecd419a08f432674f2ad2e
parent 70a3fd6c61c46c07c63cab935dca9a17d8de1709

nl80211: ignore HT/VHT capabilities without QoS/WMM

As HT/VHT depend heavily on QoS/WMM, it's not a good idea to
let userspace add clients that have HT/VHT but not QoS/WMM.
Since it does so in certain cases we've observed (client is
using HT IEs but not QoS/WMM) just ignore the HT/VHT info at
this point and don't pass it down to the drivers which might
unconditionally use it.

Cc: stable@vger.kernel.org
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

net/wireless/nl80211.c

diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index be25015..b6f84f6 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -4400,6 +4400,16 @@
 	if (parse_station_flags(info, dev->ieee80211_ptr->iftype, &params))
 		return -EINVAL;
 
+	/* HT/VHT requires QoS, but if we don't have that just ignore HT/VHT
+	 * as userspace might just pass through the capabilities from the IEs
+	 * directly, rather than enforcing this restriction and returning an
+	 * error in this case.
+	 */
+	if (!(params.sta_flags_set & BIT(NL80211_STA_FLAG_WME))) {
+		params.ht_capa = NULL;
+		params.vht_capa = NULL;
+	}
+
 	/* When you run into this, adjust the code below for the new flag */
 	BUILD_BUG_ON(NL80211_STA_FLAG_MAX != 7);