This is a workaround for VHT-enabled STAs which break the spec
and have the VHT-MCS Rx map filled in with value 3 for all eight
spacial streams.
As per spec, in section 22.1.1 Introduction to the VHT PHY
A VHT STA shall support at least single spactial stream VHT-MCSs
0 to 7 (transmit and receive) in all supported channel widths.
For some devices firmware asserts if such situation occurs.
Signed-off-by: Filip Matusiak <filip.matusiak@xxxxxxxxx>
---
net/mac80211/vht.c | 16 ++++++++++++++++
1 file changed, 16 insertions(+)
diff --git a/net/mac80211/vht.c b/net/mac80211/vht.c
index ee71576..ce93cff 100644
--- a/net/mac80211/vht.c
+++ b/net/mac80211/vht.c
@@ -270,6 +270,22 @@ ieee80211_vht_cap_ie_to_sta_vht_cap(struct ieee80211_sub_if_data *sdata,
vht_cap->vht_mcs.tx_mcs_map |= cpu_to_le16(peer_tx << i * 2);
}
+ /*
+ * This is a workaround for VHT-enabled STAs which break the spec
+ * and have the VHT-MCS Rx map filled in with value 3 for all eight
+ * spacial streams.
+ *
+ * As per spec, in section 22.1.1 Introduction to the VHT PHY
+ * A VHT STA shall support at least single spactial stream VHT-MCSs
+ * 0 to 7 (transmit and receive) in all supported channel widths.
+ */
+ if (vht_cap->vht_mcs.rx_mcs_map == cpu_to_le16(0xFFFF)) {
+ vht_cap->vht_supported = false;
+ sdata_info(sdata, "Ignoring VHT IE from %pM due to invalid rx_mcs_map\n",
+ sta->addr);
+ return;
+ }
+
/* finally set up the bandwidth */
switch (vht_cap->cap & IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK) {
case IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160MHZ:
--
2.7.4
