Commit 34373d12 authored by Vasanthakumar Thiagarajan's avatar Vasanthakumar Thiagarajan Committed by Johannes Berg
Browse files

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: default avatarVasanthakumar Thiagarajan <vthiagar@qti.qualcomm.com>
Signed-off-by: default avatarJohannes Berg <johannes.berg@intel.com>
parent b35a51c7

net/wireless/nl80211.c

+52 −0
Original line number Diff line number Diff line
@@ -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]);

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