From 34373d12f3cbb74960a73431138ef619d857996f Mon Sep 17 00:00:00 2001 From: Vasanthakumar Thiagarajan Date: Mon, 27 Feb 2017 17:04:34 +0530 Subject: cfg80211: Disallow moving out of operating DFS channel in non-ETSI For non-ETSI regulatory domain, CAC result on DFS channel may not be valid once moving out of that channel (as done during remain-on-channel, scannning and off-channel tx). Running CAC on an operating DFS channel after every off-channel operation will only add complexity and disturb the current link. Better do not allow any off-channel switch from a DFS operating channel in non-ETSI domain. Signed-off-by: Vasanthakumar Thiagarajan Signed-off-by: Johannes Berg --- net/wireless/nl80211.c | 52 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 52 insertions(+) (limited to 'net') diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c index d516527..b15903b 100644 --- a/net/wireless/nl80211.c +++ b/net/wireless/nl80211.c @@ -6556,6 +6556,19 @@ static int nl80211_parse_random_mac(struct nlattr **attrs, return 0; } +static bool cfg80211_off_channel_oper_allowed(struct wireless_dev *wdev) +{ + ASSERT_WDEV_LOCK(wdev); + + if (!cfg80211_beaconing_iface_active(wdev)) + return true; + + if (!(wdev->chandef.chan->flags & IEEE80211_CHAN_RADAR)) + return true; + + return regulatory_pre_cac_allowed(wdev->wiphy); +} + static int nl80211_trigger_scan(struct sk_buff *skb, struct genl_info *info) { struct cfg80211_registered_device *rdev = info->user_ptr[0]; @@ -6681,6 +6694,25 @@ static int nl80211_trigger_scan(struct sk_buff *skb, struct genl_info *info) request->n_channels = i; + wdev_lock(wdev); + if (!cfg80211_off_channel_oper_allowed(wdev)) { + struct ieee80211_channel *chan; + + if (request->n_channels != 1) { + wdev_unlock(wdev); + err = -EBUSY; + goto out_free; + } + + chan = request->channels[0]; + if (chan->center_freq != wdev->chandef.chan->center_freq) { + wdev_unlock(wdev); + err = -EBUSY; + goto out_free; + } + } + wdev_unlock(wdev); + i = 0; if (n_ssids) { nla_for_each_nested(attr, info->attrs[NL80211_ATTR_SCAN_SSIDS], tmp) { @@ -9103,6 +9135,7 @@ static int nl80211_remain_on_channel(struct sk_buff *skb, struct cfg80211_registered_device *rdev = info->user_ptr[0]; struct wireless_dev *wdev = info->user_ptr[1]; struct cfg80211_chan_def chandef; + const struct cfg80211_chan_def *compat_chandef; struct sk_buff *msg; void *hdr; u64 cookie; @@ -9131,6 +9164,18 @@ static int nl80211_remain_on_channel(struct sk_buff *skb, if (err) return err; + wdev_lock(wdev); + if (!cfg80211_off_channel_oper_allowed(wdev) && + !cfg80211_chandef_identical(&wdev->chandef, &chandef)) { + compat_chandef = cfg80211_chandef_compatible(&wdev->chandef, + &chandef); + if (compat_chandef != &chandef) { + wdev_unlock(wdev); + return -EBUSY; + } + } + wdev_unlock(wdev); + msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); if (!msg) return -ENOMEM; @@ -9306,6 +9351,13 @@ static int nl80211_tx_mgmt(struct sk_buff *skb, struct genl_info *info) if (!chandef.chan && params.offchan) return -EINVAL; + wdev_lock(wdev); + if (params.offchan && !cfg80211_off_channel_oper_allowed(wdev)) { + wdev_unlock(wdev); + return -EBUSY; + } + wdev_unlock(wdev); + params.buf = nla_data(info->attrs[NL80211_ATTR_FRAME]); params.len = nla_len(info->attrs[NL80211_ATTR_FRAME]); -- cgit v1.1