[PATCH 3.10 13/50] cfg80211: Fix 160 MHz channels with 80+80 and 160 MHz drivers

Greg Kroah-Hartman
2015-01-25T19:32:57Z

From: Jouni Malinen <jouni@qca.qualcomm.com>

commit 08f6f147773b23b765b94633a8eaa82e7defcf4c upstream.

The VHT supported channel width field is a two bit integer, not a
bitfield. cfg80211_chandef_usable() was interpreting it incorrectly and
ended up rejecting 160 MHz channel width if the driver indicated support
for both 160 and 80+80 MHz channels.

Fixes: 3d9d1d6656a73 ("nl80211/cfg80211: support VHT channel configuration")
(however, no real drivers had 160 MHz support it until 3.16)
Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
net/wireless/chan.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)

--- a/net/wireless/chan.c
+++ b/net/wireless/chan.c
@@ -338,7 +338,7 @@ bool cfg80211_chandef_usable(struct wiph
{
struct ieee80211_sta_ht_cap *ht_cap;
struct ieee80211_sta_vht_cap *vht_cap;
- u32 width, control_freq;
+ u32 width, control_freq, cap;

if (WARN_ON(!cfg80211_chandef_valid(chandef)))
return false;
@@ -370,7 +370,8 @@ bool cfg80211_chandef_usable(struct wiph
return false;
break;
case NL80211_CHAN_WIDTH_80P80:
- if (!(vht_cap->cap & IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ))
+ cap = vht_cap->cap & IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK;
+ if (cap != IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ)
return false;
case NL80211_CHAN_WIDTH_80:
if (!vht_cap->vht_supported)
@@ -381,7 +382,9 @@ bool cfg80211_chandef_usable(struct wiph
case NL80211_CHAN_WIDTH_160:
if (!vht_cap->vht_supported)
return false;
- if (!(vht_cap->cap & IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160MHZ))
+ cap = vht_cap->cap & IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK;
+ if (cap != IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160MHZ &&
+ cap != IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ)
return false;
prohibited_flags |= IEEE80211_CHAN_NO_160MHZ;
width = 160;