From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932922Ab0LHBGo (ORCPT ); Tue, 7 Dec 2010 20:06:44 -0500 Received: from kroah.org ([198.145.64.141]:33919 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932917Ab0LHBEL (ORCPT ); Tue, 7 Dec 2010 20:04:11 -0500 X-Mailbox-Line: From gregkh@clark.site Tue Dec 7 16:57:49 2010 Message-Id: <20101208005749.342168693@clark.site> User-Agent: quilt/0.48-11.2 Date: Tue, 07 Dec 2010 17:00:56 -0800 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: stable-review@kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, "Luis R. Rodriguez" , "John W. Linville" Subject: [279/289] cfg80211: fix extension channel checks to initiate communication In-Reply-To: <20101208005821.GA2922@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.36-stable review patch. If anyone has any objections, please let us know. ------------------ From: Luis R. Rodriguez commit 9236d838c920e90708570d9bbd7bb82d30a38130 upstream. When operating in a mode that initiates communication and using HT40 we should fail if we cannot use both primary and secondary channels to initiate communication. Our current ht40 allowmap only covers STA mode of operation, for beaconing modes we need a check on the fly as the mode of operation is dynamic and there other flags other than disable which we should read to check if we can initiate communication. Do not allow for initiating communication if our secondary HT40 channel has is either disabled, has a passive scan flag, a no-ibss flag or is a radar channel. Userspace now has similar checks but this is also needed in-kernel. Reported-by: Jouni Malinen Signed-off-by: Luis R. Rodriguez Signed-off-by: John W. Linville Signed-off-by: Greg Kroah-Hartman --- net/wireless/chan.c | 51 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 51 insertions(+) --- a/net/wireless/chan.c +++ b/net/wireless/chan.c @@ -44,6 +44,36 @@ rdev_freq_to_chan(struct cfg80211_regist return chan; } +static bool can_beacon_sec_chan(struct wiphy *wiphy, + struct ieee80211_channel *chan, + enum nl80211_channel_type channel_type) +{ + struct ieee80211_channel *sec_chan; + int diff; + + switch (channel_type) { + case NL80211_CHAN_HT40PLUS: + diff = 20; + case NL80211_CHAN_HT40MINUS: + diff = -20; + default: + return false; + } + + sec_chan = ieee80211_get_channel(wiphy, chan->center_freq + diff); + if (!sec_chan) + return false; + + /* we'll need a DFS capability later */ + if (sec_chan->flags & (IEEE80211_CHAN_DISABLED | + IEEE80211_CHAN_PASSIVE_SCAN | + IEEE80211_CHAN_NO_IBSS | + IEEE80211_CHAN_RADAR)) + return false; + + return true; +} + int cfg80211_set_freq(struct cfg80211_registered_device *rdev, struct wireless_dev *wdev, int freq, enum nl80211_channel_type channel_type) @@ -68,6 +98,27 @@ int cfg80211_set_freq(struct cfg80211_re if (!chan) return -EINVAL; + /* Both channels should be able to initiate communication */ + if (wdev && (wdev->iftype == NL80211_IFTYPE_ADHOC || + wdev->iftype == NL80211_IFTYPE_AP || + wdev->iftype == NL80211_IFTYPE_AP_VLAN || + wdev->iftype == NL80211_IFTYPE_MESH_POINT)) { + switch (channel_type) { + case NL80211_CHAN_HT40PLUS: + case NL80211_CHAN_HT40MINUS: + if (!can_beacon_sec_chan(&rdev->wiphy, chan, + channel_type)) { + printk(KERN_DEBUG + "cfg80211: Secondary channel not " + "allowed to initiate communication\n"); + return -EINVAL; + } + break; + default: + break; + } + } + result = rdev->ops->set_channel(&rdev->wiphy, wdev ? wdev->netdev : NULL, chan, channel_type);