From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Greg Kroah-Hartman , alan@lxorguk.ukuu.org.uk, Florian Reitmeir , Johannes Berg Subject: [ 078/101] mac80211: connect with HT20 if HT40 is not permitted Date: Mon, 29 Oct 2012 14:35:31 -0700 Message-Id: <20121029213248.972848350@linuxfoundation.org> In-Reply-To: <20121029213240.128426598@linuxfoundation.org> References: <20121029213240.128426598@linuxfoundation.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Johannes Berg commit 3a40414f826a8f1096d9b94c4a53ef91b25ba28d upstream. Some changes to fix issues with HT40 APs in Korea and follow-up changes to allow using HT40 even if the local regulatory database disallows it caused issues with iwlwifi (and could cause issues with other devices); iwlwifi firmware would assert if you tried to connect to an AP that has an invalid configuration (e.g. using HT40- on channel 140.) Fix this, while avoiding the "Korean AP" issue by disabling HT40 and advertising HT20 to the AP when connecting. Reported-by: Florian Reitmeir Tested-by: Florian Reitmeir Signed-off-by: Johannes Berg Signed-off-by: Greg Kroah-Hartman --- net/mac80211/mlme.c | 30 ++++++++++++++++++++---------- 1 file changed, 20 insertions(+), 10 deletions(-) --- a/net/mac80211/mlme.c +++ b/net/mac80211/mlme.c @@ -3065,22 +3065,32 @@ static int ieee80211_prep_connection(str ht_cfreq, ht_oper->primary_chan, cbss->channel->band); ht_oper = NULL; + } else { + channel_type = NL80211_CHAN_HT20; } } - if (ht_oper) { - channel_type = NL80211_CHAN_HT20; + if (ht_oper && sband->ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40) { + /* + * cfg80211 already verified that the channel itself can + * be used, but it didn't check that we can do the right + * HT type, so do that here as well. If HT40 isn't allowed + * on this channel, disable 40 MHz operation. + */ - if (sband->ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40) { - switch (ht_oper->ht_param & - IEEE80211_HT_PARAM_CHA_SEC_OFFSET) { - case IEEE80211_HT_PARAM_CHA_SEC_ABOVE: + switch (ht_oper->ht_param & IEEE80211_HT_PARAM_CHA_SEC_OFFSET) { + case IEEE80211_HT_PARAM_CHA_SEC_ABOVE: + if (cbss->channel->flags & IEEE80211_CHAN_NO_HT40PLUS) + ifmgd->flags |= IEEE80211_STA_DISABLE_40MHZ; + else channel_type = NL80211_CHAN_HT40PLUS; - break; - case IEEE80211_HT_PARAM_CHA_SEC_BELOW: + break; + case IEEE80211_HT_PARAM_CHA_SEC_BELOW: + if (cbss->channel->flags & IEEE80211_CHAN_NO_HT40MINUS) + ifmgd->flags |= IEEE80211_STA_DISABLE_40MHZ; + else channel_type = NL80211_CHAN_HT40MINUS; - break; - } + break; } }