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author | Filip Matusiak <filip.matusiak@tieto.com> | 2016-11-02 10:04:26 +0100 |
---|---|---|
committer | Johannes Berg <johannes.berg@intel.com> | 2016-11-15 14:18:43 +0100 |
commit | c8eaf3479e521e973eb2d4111b8ee8f5b7b564ab (patch) | |
tree | 8ec69c8c39464f3e38e53326dd8880d17c8f56b0 /net | |
parent | 269ebce4531b8edc4224259a02143181a1c1d77c (diff) | |
download | linux-c8eaf3479e521e973eb2d4111b8ee8f5b7b564ab.tar.bz2 |
mac80211: Ignore VHT IE from peer with wrong rx_mcs_map
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, an example is AR9462 in AP mode.
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.
Some devices in STA mode will get firmware assert when trying to
associate, examples are QCA9377 & QCA6174.
Packet example of broken VHT Cap IE of AR9462:
Tag: VHT Capabilities (IEEE Std 802.11ac/D3.1)
Tag Number: VHT Capabilities (IEEE Std 802.11ac/D3.1) (191)
Tag length: 12
VHT Capabilities Info: 0x00000000
VHT Supported MCS Set
Rx MCS Map: 0xffff
.... .... .... ..11 = Rx 1 SS: Not Supported (0x0003)
.... .... .... 11.. = Rx 2 SS: Not Supported (0x0003)
.... .... ..11 .... = Rx 3 SS: Not Supported (0x0003)
.... .... 11.. .... = Rx 4 SS: Not Supported (0x0003)
.... ..11 .... .... = Rx 5 SS: Not Supported (0x0003)
.... 11.. .... .... = Rx 6 SS: Not Supported (0x0003)
..11 .... .... .... = Rx 7 SS: Not Supported (0x0003)
11.. .... .... .... = Rx 8 SS: Not Supported (0x0003)
...0 0000 0000 0000 = Rx Highest Long GI Data Rate (in Mb/s, 0 = subfield not in use): 0x0000
Tx MCS Map: 0xffff
...0 0000 0000 0000 = Tx Highest Long GI Data Rate (in Mb/s, 0 = subfield not in use): 0x0000
Signed-off-by: Filip Matusiak <filip.matusiak@tieto.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Diffstat (limited to 'net')
-rw-r--r-- | net/mac80211/vht.c | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/net/mac80211/vht.c b/net/mac80211/vht.c index ee715764a828..6832bf6ab69f 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, an example is AR9462. + * + * 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: |