1 files changed, 529 insertions, 108 deletions

diff --git a/net/mac80211/ibss.c b/net/mac80211/ibss.c
index a12afe77bb2..18ee0a256b1 100644
--- a/net/mac80211/ibss.c
+++ b/net/mac80211/ibss.c
@@ -39,7 +39,8 @@ ieee80211_ibss_build_presp(struct ieee80211_sub_if_data *sdata,
 			   const int beacon_int, const u32 basic_rates,
 			   const u16 capability, u64 tsf,
 			   struct cfg80211_chan_def *chandef,
-			   bool *have_higher_than_11mbit)
+			   bool *have_higher_than_11mbit,
+			   struct cfg80211_csa_settings *csa_settings)
 {
 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 	struct ieee80211_local *local = sdata->local;
@@ -59,6 +60,7 @@ ieee80211_ibss_build_presp(struct ieee80211_sub_if_data *sdata,
 		    2 + 8 /* max Supported Rates */ +
 		    3 /* max DS params */ +
 		    4 /* IBSS params */ +
+		    5 /* Channel Switch Announcement */ +
 		    2 + (IEEE80211_MAX_SUPP_RATES - 8) +
 		    2 + sizeof(struct ieee80211_ht_cap) +
 		    2 + sizeof(struct ieee80211_ht_operation) +
@@ -135,6 +137,16 @@ ieee80211_ibss_build_presp(struct ieee80211_sub_if_data *sdata,
 	*pos++ = 0;
 	*pos++ = 0;
 
+	if (csa_settings) {
+		*pos++ = WLAN_EID_CHANNEL_SWITCH;
+		*pos++ = 3;
+		*pos++ = csa_settings->block_tx ? 1 : 0;
+		*pos++ = ieee80211_frequency_to_channel(
+				csa_settings->chandef.chan->center_freq);
+		sdata->csa_counter_offset_beacon[0] = (pos - presp->head);
+		*pos++ = csa_settings->count;
+	}
+
 	/* put the remaining rates in WLAN_EID_EXT_SUPP_RATES */
 	if (rates_n > 8) {
 		*pos++ = WLAN_EID_EXT_SUPP_RATES;
@@ -208,7 +220,6 @@ static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
 {
 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 	struct ieee80211_local *local = sdata->local;
-	struct ieee80211_supported_band *sband;
 	struct ieee80211_mgmt *mgmt;
 	struct cfg80211_bss *bss;
 	u32 bss_change;
@@ -217,6 +228,8 @@ static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
 	struct beacon_data *presp;
 	enum nl80211_bss_scan_width scan_width;
 	bool have_higher_than_11mbit;
+	bool radar_required;
+	int err;
 
 	sdata_assert_lock(sdata);
 
@@ -235,11 +248,12 @@ static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
 		ieee80211_bss_info_change_notify(sdata,
 						 BSS_CHANGED_IBSS |
 						 BSS_CHANGED_BEACON_ENABLED);
+		drv_leave_ibss(local, sdata);
 	}
 
 	presp = rcu_dereference_protected(ifibss->presp,
 					  lockdep_is_held(&sdata->wdev.mtx));
-	rcu_assign_pointer(ifibss->presp, NULL);
+	RCU_INIT_POINTER(ifibss->presp, NULL);
 	if (presp)
 		kfree_rcu(presp, rcu_head);
 
@@ -248,7 +262,8 @@ static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
 	/* make a copy of the chandef, it could be modified below. */
 	chandef = *req_chandef;
 	chan = chandef.chan;
-	if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef)) {
+	if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef,
+				     NL80211_IFTYPE_ADHOC)) {
 		if (chandef.width == NL80211_CHAN_WIDTH_5 ||
 		    chandef.width == NL80211_CHAN_WIDTH_10 ||
 		    chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
@@ -259,24 +274,47 @@ static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
 		}
 		chandef.width = NL80211_CHAN_WIDTH_20;
 		chandef.center_freq1 = chan->center_freq;
+		/* check again for downgraded chandef */
+		if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef,
+					     NL80211_IFTYPE_ADHOC)) {
+			sdata_info(sdata,
+				   "Failed to join IBSS, beacons forbidden\n");
+			return;
+		}
 	}
 
-	ieee80211_vif_release_channel(sdata);
+	err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
+					    &chandef, NL80211_IFTYPE_ADHOC);
+	if (err < 0) {
+		sdata_info(sdata,
+			   "Failed to join IBSS, invalid chandef\n");
+		return;
+	}
+	if (err > 0 && !ifibss->userspace_handles_dfs) {
+		sdata_info(sdata,
+			   "Failed to join IBSS, DFS channel without control program\n");
+		return;
+	}
+
+	radar_required = err;
+
+	mutex_lock(&local->mtx);
 	if (ieee80211_vif_use_channel(sdata, &chandef,
 				      ifibss->fixed_channel ?
 					IEEE80211_CHANCTX_SHARED :
 					IEEE80211_CHANCTX_EXCLUSIVE)) {
 		sdata_info(sdata, "Failed to join IBSS, no channel context\n");
+		mutex_unlock(&local->mtx);
 		return;
 	}
+	sdata->radar_required = radar_required;
+	mutex_unlock(&local->mtx);
 
 	memcpy(ifibss->bssid, bssid, ETH_ALEN);
 
-	sband = local->hw.wiphy->bands[chan->band];
-
 	presp = ieee80211_ibss_build_presp(sdata, beacon_int, basic_rates,
 					   capability, tsf, &chandef,
-					   &have_higher_than_11mbit);
+					   &have_higher_than_11mbit, NULL);
 	if (!presp)
 		return;
 
@@ -317,11 +355,28 @@ static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
 	else
 		sdata->flags &= ~IEEE80211_SDATA_OPERATING_GMODE;
 
+	ieee80211_set_wmm_default(sdata, true);
+
 	sdata->vif.bss_conf.ibss_joined = true;
 	sdata->vif.bss_conf.ibss_creator = creator;
-	ieee80211_bss_info_change_notify(sdata, bss_change);
 
-	ieee80211_set_wmm_default(sdata, true);
+	err = drv_join_ibss(local, sdata);
+	if (err) {
+		sdata->vif.bss_conf.ibss_joined = false;
+		sdata->vif.bss_conf.ibss_creator = false;
+		sdata->vif.bss_conf.enable_beacon = false;
+		sdata->vif.bss_conf.ssid_len = 0;
+		RCU_INIT_POINTER(ifibss->presp, NULL);
+		kfree_rcu(presp, rcu_head);
+		mutex_lock(&local->mtx);
+		ieee80211_vif_release_channel(sdata);
+		mutex_unlock(&local->mtx);
+		sdata_info(sdata, "Failed to join IBSS, driver failure: %d\n",
+			   err);
+		return;
+	}
+
+	ieee80211_bss_info_change_notify(sdata, bss_change);
 
 	ifibss->state = IEEE80211_IBSS_MLME_JOINED;
 	mod_timer(&ifibss->timer,
@@ -333,7 +388,7 @@ static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
 					      presp->head_len, 0, GFP_KERNEL);
 	cfg80211_put_bss(local->hw.wiphy, bss);
 	netif_carrier_on(sdata->dev);
-	cfg80211_ibss_joined(sdata->dev, ifibss->bssid, GFP_KERNEL);
+	cfg80211_ibss_joined(sdata->dev, ifibss->bssid, chan, GFP_KERNEL);
 }
 
 static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
@@ -416,6 +471,111 @@ static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
 				  tsf, false);
 }
 
+int ieee80211_ibss_csa_beacon(struct ieee80211_sub_if_data *sdata,
+			      struct cfg80211_csa_settings *csa_settings)
+{
+	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
+	struct beacon_data *presp, *old_presp;
+	struct cfg80211_bss *cbss;
+	const struct cfg80211_bss_ies *ies;
+	u16 capability;
+	u64 tsf;
+	int ret = 0;
+
+	sdata_assert_lock(sdata);
+
+	capability = WLAN_CAPABILITY_IBSS;
+
+	if (ifibss->privacy)
+		capability |= WLAN_CAPABILITY_PRIVACY;
+
+	cbss = cfg80211_get_bss(sdata->local->hw.wiphy, ifibss->chandef.chan,
+				ifibss->bssid, ifibss->ssid,
+				ifibss->ssid_len, WLAN_CAPABILITY_IBSS |
+				WLAN_CAPABILITY_PRIVACY,
+				capability);
+
+	if (WARN_ON(!cbss)) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	rcu_read_lock();
+	ies = rcu_dereference(cbss->ies);
+	tsf = ies->tsf;
+	rcu_read_unlock();
+	cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
+
+	old_presp = rcu_dereference_protected(ifibss->presp,
+					  lockdep_is_held(&sdata->wdev.mtx));
+
+	presp = ieee80211_ibss_build_presp(sdata,
+					   sdata->vif.bss_conf.beacon_int,
+					   sdata->vif.bss_conf.basic_rates,
+					   capability, tsf, &ifibss->chandef,
+					   NULL, csa_settings);
+	if (!presp) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	rcu_assign_pointer(ifibss->presp, presp);
+	if (old_presp)
+		kfree_rcu(old_presp, rcu_head);
+
+	return BSS_CHANGED_BEACON;
+ out:
+	return ret;
+}
+
+int ieee80211_ibss_finish_csa(struct ieee80211_sub_if_data *sdata)
+{
+	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
+	struct cfg80211_bss *cbss;
+	int err, changed = 0;
+	u16 capability;
+
+	sdata_assert_lock(sdata);
+
+	/* update cfg80211 bss information with the new channel */
+	if (!is_zero_ether_addr(ifibss->bssid)) {
+		capability = WLAN_CAPABILITY_IBSS;
+
+		if (ifibss->privacy)
+			capability |= WLAN_CAPABILITY_PRIVACY;
+
+		cbss = cfg80211_get_bss(sdata->local->hw.wiphy,
+					ifibss->chandef.chan,
+					ifibss->bssid, ifibss->ssid,
+					ifibss->ssid_len, WLAN_CAPABILITY_IBSS |
+					WLAN_CAPABILITY_PRIVACY,
+					capability);
+		/* XXX: should not really modify cfg80211 data */
+		if (cbss) {
+			cbss->channel = sdata->csa_chandef.chan;
+			cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
+		}
+	}
+
+	ifibss->chandef = sdata->csa_chandef;
+
+	/* generate the beacon */
+	err = ieee80211_ibss_csa_beacon(sdata, NULL);
+	if (err < 0)
+		return err;
+
+	changed |= err;
+
+	return changed;
+}
+
+void ieee80211_ibss_stop(struct ieee80211_sub_if_data *sdata)
+{
+	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
+
+	cancel_work_sync(&ifibss->csa_connection_drop_work);
+}
+
 static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta)
 	__acquires(RCU)
 {
@@ -499,6 +659,290 @@ ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata, const u8 *bssid,
 	return ieee80211_ibss_finish_sta(sta);
 }
 
+static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata)
+{
+	struct ieee80211_local *local = sdata->local;
+	int active = 0;
+	struct sta_info *sta;
+
+	sdata_assert_lock(sdata);
+
+	rcu_read_lock();
+
+	list_for_each_entry_rcu(sta, &local->sta_list, list) {
+		if (sta->sdata == sdata &&
+		    time_after(sta->last_rx + IEEE80211_IBSS_MERGE_INTERVAL,
+			       jiffies)) {
+			active++;
+			break;
+		}
+	}
+
+	rcu_read_unlock();
+
+	return active;
+}
+
+static void ieee80211_ibss_disconnect(struct ieee80211_sub_if_data *sdata)
+{
+	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
+	struct ieee80211_local *local = sdata->local;
+	struct cfg80211_bss *cbss;
+	struct beacon_data *presp;
+	struct sta_info *sta;
+	u16 capability;
+
+	if (!is_zero_ether_addr(ifibss->bssid)) {
+		capability = WLAN_CAPABILITY_IBSS;
+
+		if (ifibss->privacy)
+			capability |= WLAN_CAPABILITY_PRIVACY;
+
+		cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->chandef.chan,
+					ifibss->bssid, ifibss->ssid,
+					ifibss->ssid_len, WLAN_CAPABILITY_IBSS |
+					WLAN_CAPABILITY_PRIVACY,
+					capability);
+
+		if (cbss) {
+			cfg80211_unlink_bss(local->hw.wiphy, cbss);
+			cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
+		}
+	}
+
+	ifibss->state = IEEE80211_IBSS_MLME_SEARCH;
+
+	sta_info_flush(sdata);
+
+	spin_lock_bh(&ifibss->incomplete_lock);
+	while (!list_empty(&ifibss->incomplete_stations)) {
+		sta = list_first_entry(&ifibss->incomplete_stations,
+				       struct sta_info, list);
+		list_del(&sta->list);
+		spin_unlock_bh(&ifibss->incomplete_lock);
+
+		sta_info_free(local, sta);
+		spin_lock_bh(&ifibss->incomplete_lock);
+	}
+	spin_unlock_bh(&ifibss->incomplete_lock);
+
+	netif_carrier_off(sdata->dev);
+
+	sdata->vif.bss_conf.ibss_joined = false;
+	sdata->vif.bss_conf.ibss_creator = false;
+	sdata->vif.bss_conf.enable_beacon = false;
+	sdata->vif.bss_conf.ssid_len = 0;
+
+	/* remove beacon */
+	presp = rcu_dereference_protected(ifibss->presp,
+					  lockdep_is_held(&sdata->wdev.mtx));
+	RCU_INIT_POINTER(sdata->u.ibss.presp, NULL);
+	if (presp)
+		kfree_rcu(presp, rcu_head);
+
+	clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state);
+	ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED |
+						BSS_CHANGED_IBSS);
+	drv_leave_ibss(local, sdata);
+	mutex_lock(&local->mtx);
+	ieee80211_vif_release_channel(sdata);
+	mutex_unlock(&local->mtx);
+}
+
+static void ieee80211_csa_connection_drop_work(struct work_struct *work)
+{
+	struct ieee80211_sub_if_data *sdata =
+		container_of(work, struct ieee80211_sub_if_data,
+			     u.ibss.csa_connection_drop_work);
+
+	sdata_lock(sdata);
+
+	ieee80211_ibss_disconnect(sdata);
+	synchronize_rcu();
+	skb_queue_purge(&sdata->skb_queue);
+
+	/* trigger a scan to find another IBSS network to join */
+	ieee80211_queue_work(&sdata->local->hw, &sdata->work);
+
+	sdata_unlock(sdata);
+}
+
+static void ieee80211_ibss_csa_mark_radar(struct ieee80211_sub_if_data *sdata)
+{
+	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
+	int err;
+
+	/* if the current channel is a DFS channel, mark the channel as
+	 * unavailable.
+	 */
+	err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
+					    &ifibss->chandef,
+					    NL80211_IFTYPE_ADHOC);
+	if (err > 0)
+		cfg80211_radar_event(sdata->local->hw.wiphy, &ifibss->chandef,
+				     GFP_ATOMIC);
+}
+
+static bool
+ieee80211_ibss_process_chanswitch(struct ieee80211_sub_if_data *sdata,
+				  struct ieee802_11_elems *elems,
+				  bool beacon)
+{
+	struct cfg80211_csa_settings params;
+	struct ieee80211_csa_ie csa_ie;
+	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
+	enum nl80211_channel_type ch_type;
+	int err;
+	u32 sta_flags;
+
+	sdata_assert_lock(sdata);
+
+	sta_flags = IEEE80211_STA_DISABLE_VHT;
+	switch (ifibss->chandef.width) {
+	case NL80211_CHAN_WIDTH_5:
+	case NL80211_CHAN_WIDTH_10:
+	case NL80211_CHAN_WIDTH_20_NOHT:
+		sta_flags |= IEEE80211_STA_DISABLE_HT;
+		/* fall through */
+	case NL80211_CHAN_WIDTH_20:
+		sta_flags |= IEEE80211_STA_DISABLE_40MHZ;
+		break;
+	default:
+		break;
+	}
+
+	memset(&params, 0, sizeof(params));
+	memset(&csa_ie, 0, sizeof(csa_ie));
+	err = ieee80211_parse_ch_switch_ie(sdata, elems, beacon,
+					   ifibss->chandef.chan->band,
+					   sta_flags, ifibss->bssid, &csa_ie);
+	/* can't switch to destination channel, fail */
+	if (err < 0)
+		goto disconnect;
+
+	/* did not contain a CSA */
+	if (err)
+		return false;
+
+	/* channel switch is not supported, disconnect */
+	if (!(sdata->local->hw.wiphy->flags & WIPHY_FLAG_HAS_CHANNEL_SWITCH))
+		goto disconnect;
+
+	params.count = csa_ie.count;
+	params.chandef = csa_ie.chandef;
+
+	switch (ifibss->chandef.width) {
+	case NL80211_CHAN_WIDTH_20_NOHT:
+	case NL80211_CHAN_WIDTH_20:
+	case NL80211_CHAN_WIDTH_40:
+		/* keep our current HT mode (HT20/HT40+/HT40-), even if
+		 * another mode  has been announced. The mode is not adopted
+		 * within the beacon while doing CSA and we should therefore
+		 * keep the mode which we announce.
+		 */
+		ch_type = cfg80211_get_chandef_type(&ifibss->chandef);
+		cfg80211_chandef_create(&params.chandef, params.chandef.chan,
+					ch_type);
+		break;
+	case NL80211_CHAN_WIDTH_5:
+	case NL80211_CHAN_WIDTH_10:
+		if (params.chandef.width != ifibss->chandef.width) {
+			sdata_info(sdata,
+				   "IBSS %pM received channel switch from incompatible channel width (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n",
+				   ifibss->bssid,
+				   params.chandef.chan->center_freq,
+				   params.chandef.width,
+				   params.chandef.center_freq1,
+				   params.chandef.center_freq2);
+			goto disconnect;
+		}
+		break;
+	default:
+		/* should not happen, sta_flags should prevent VHT modes. */
+		WARN_ON(1);
+		goto disconnect;
+	}
+
+	if (!cfg80211_reg_can_beacon(sdata->local->hw.wiphy, &params.chandef,
+				     NL80211_IFTYPE_ADHOC)) {
+		sdata_info(sdata,
+			   "IBSS %pM switches to unsupported channel (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n",
+			   ifibss->bssid,
+			   params.chandef.chan->center_freq,
+			   params.chandef.width,
+			   params.chandef.center_freq1,
+			   params.chandef.center_freq2);
+		goto disconnect;
+	}
+
+	err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
+					    &params.chandef,
+					    NL80211_IFTYPE_ADHOC);
+	if (err < 0)
+		goto disconnect;
+	if (err > 0 && !ifibss->userspace_handles_dfs) {
+		/* IBSS-DFS only allowed with a control program */
+		goto disconnect;
+	}
+
+	params.radar_required = err;
+
+	if (cfg80211_chandef_identical(&params.chandef,
+				       &sdata->vif.bss_conf.chandef)) {
+		ibss_dbg(sdata,
+			 "received csa with an identical chandef, ignoring\n");
+		return true;
+	}
+
+	/* all checks done, now perform the channel switch. */
+	ibss_dbg(sdata,
+		 "received channel switch announcement to go to channel %d MHz\n",
+		 params.chandef.chan->center_freq);
+
+	params.block_tx = !!csa_ie.mode;
+
+	if (ieee80211_channel_switch(sdata->local->hw.wiphy, sdata->dev,
+				     &params))
+		goto disconnect;
+
+	ieee80211_ibss_csa_mark_radar(sdata);
+
+	return true;
+disconnect:
+	ibss_dbg(sdata, "Can't handle channel switch, disconnect\n");
+	ieee80211_queue_work(&sdata->local->hw,
+			     &ifibss->csa_connection_drop_work);
+
+	ieee80211_ibss_csa_mark_radar(sdata);
+
+	return true;
+}
+
+static void
+ieee80211_rx_mgmt_spectrum_mgmt(struct ieee80211_sub_if_data *sdata,
+				struct ieee80211_mgmt *mgmt, size_t len,
+				struct ieee80211_rx_status *rx_status,
+				struct ieee802_11_elems *elems)
+{
+	int required_len;
+
+	if (len < IEEE80211_MIN_ACTION_SIZE + 1)
+		return;
+
+	/* CSA is the only action we handle for now */
+	if (mgmt->u.action.u.measurement.action_code !=
+	    WLAN_ACTION_SPCT_CHL_SWITCH)
+		return;
+
+	required_len = IEEE80211_MIN_ACTION_SIZE +
+		       sizeof(mgmt->u.action.u.chan_switch);
+	if (len < required_len)
+		return;
+
+	if (!sdata->vif.csa_active)
+		ieee80211_ibss_process_chanswitch(sdata, elems, false);
+}
+
 static void ieee80211_rx_mgmt_deauth_ibss(struct ieee80211_sub_if_data *sdata,
 					  struct ieee80211_mgmt *mgmt,
 					  size_t len)
@@ -550,7 +994,6 @@ static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
 				  struct ieee802_11_elems *elems)
 {
 	struct ieee80211_local *local = sdata->local;
-	int freq;
 	struct cfg80211_bss *cbss;
 	struct ieee80211_bss *bss;
 	struct sta_info *sta;
@@ -562,15 +1005,8 @@ static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
 	struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band];
 	bool rates_updated = false;
 
-	if (elems->ds_params)
-		freq = ieee80211_channel_to_frequency(elems->ds_params[0],
-						      band);
-	else
-		freq = rx_status->freq;
-
-	channel = ieee80211_get_channel(local->hw.wiphy, freq);
-
-	if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
+	channel = ieee80211_get_channel(local->hw.wiphy, rx_status->freq);
+	if (!channel)
 		return;
 
 	if (sdata->vif.type == NL80211_IFTYPE_ADHOC &&
@@ -661,10 +1097,6 @@ static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
 
 	/* check if we need to merge IBSS */
 
-	/* we use a fixed BSSID */
-	if (sdata->u.ibss.fixed_bssid)
-		goto put_bss;
-
 	/* not an IBSS */
 	if (!(cbss->capability & WLAN_CAPABILITY_IBSS))
 		goto put_bss;
@@ -680,10 +1112,19 @@ static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
 				sdata->u.ibss.ssid_len))
 		goto put_bss;
 
+	/* process channel switch */
+	if (sdata->vif.csa_active ||
+	    ieee80211_ibss_process_chanswitch(sdata, elems, true))
+		goto put_bss;
+
 	/* same BSSID */
 	if (ether_addr_equal(cbss->bssid, sdata->u.ibss.bssid))
 		goto put_bss;
 
+	/* we use a fixed BSSID */
+	if (sdata->u.ibss.fixed_bssid)
+		goto put_bss;
+
 	if (ieee80211_have_rx_timestamp(rx_status)) {
 		/* time when timestamp field was received */
 		rx_timestamp =
@@ -775,30 +1216,6 @@ void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata,
 	ieee80211_queue_work(&local->hw, &sdata->work);
 }
 
-static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata)
-{
-	struct ieee80211_local *local = sdata->local;
-	int active = 0;
-	struct sta_info *sta;
-
-	sdata_assert_lock(sdata);
-
-	rcu_read_lock();
-
-	list_for_each_entry_rcu(sta, &local->sta_list, list) {
-		if (sta->sdata == sdata &&
-		    time_after(sta->last_rx + IEEE80211_IBSS_MERGE_INTERVAL,
-			       jiffies)) {
-			active++;
-			break;
-		}
-	}
-
-	rcu_read_unlock();
-
-	return active;
-}
-
 static void ieee80211_ibss_sta_expire(struct ieee80211_sub_if_data *sdata)
 {
 	struct ieee80211_local *local = sdata->local;
@@ -1042,6 +1459,11 @@ static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata,
 	memcpy(((struct ieee80211_mgmt *) skb->data)->da, mgmt->sa, ETH_ALEN);
 	ibss_dbg(sdata, "Sending ProbeResp to %pM\n", mgmt->sa);
 	IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
+
+	/* avoid excessive retries for probe request to wildcard SSIDs */
+	if (pos[1] == 0)
+		IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_CTL_NO_ACK;
+
 	ieee80211_tx_skb(sdata, skb);
 }
 
@@ -1076,6 +1498,8 @@ void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
 	struct ieee80211_rx_status *rx_status;
 	struct ieee80211_mgmt *mgmt;
 	u16 fc;
+	struct ieee802_11_elems elems;
+	int ies_len;
 
 	rx_status = IEEE80211_SKB_RXCB(skb);
 	mgmt = (struct ieee80211_mgmt *) skb->data;
@@ -1101,6 +1525,27 @@ void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
 	case IEEE80211_STYPE_DEAUTH:
 		ieee80211_rx_mgmt_deauth_ibss(sdata, mgmt, skb->len);
 		break;
+	case IEEE80211_STYPE_ACTION:
+		switch (mgmt->u.action.category) {
+		case WLAN_CATEGORY_SPECTRUM_MGMT:
+			ies_len = skb->len -
+				  offsetof(struct ieee80211_mgmt,
+					   u.action.u.chan_switch.variable);
+
+			if (ies_len < 0)
+				break;
+
+			ieee802_11_parse_elems(
+				mgmt->u.action.u.chan_switch.variable,
+				ies_len, true, &elems);
+
+			if (elems.parse_error)
+				break;
+
+			ieee80211_rx_mgmt_spectrum_mgmt(sdata, mgmt, skb->len,
+							rx_status, &elems);
+			break;
+		}
 	}
 
  mgmt_out:
@@ -1167,6 +1612,8 @@ void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata)
 		    (unsigned long) sdata);
 	INIT_LIST_HEAD(&ifibss->incomplete_stations);
 	spin_lock_init(&ifibss->incomplete_lock);
+	INIT_WORK(&ifibss->csa_connection_drop_work,
+		  ieee80211_csa_connection_drop_work);
 }
 
 /* scan finished notification */
@@ -1192,7 +1639,33 @@ int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
 	u32 changed = 0;
 	u32 rate_flags;
 	struct ieee80211_supported_band *sband;
+	enum ieee80211_chanctx_mode chanmode;
+	struct ieee80211_local *local = sdata->local;
+	int radar_detect_width = 0;
 	int i;
+	int ret;
+
+	ret = cfg80211_chandef_dfs_required(local->hw.wiphy,
+					    &params->chandef,
+					    sdata->wdev.iftype);
+	if (ret < 0)
+		return ret;
+
+	if (ret > 0) {
+		if (!params->userspace_handles_dfs)
+			return -EINVAL;
+		radar_detect_width = BIT(params->chandef.width);
+	}
+
+	chanmode = (params->channel_fixed && !ret) ?
+		IEEE80211_CHANCTX_SHARED : IEEE80211_CHANCTX_EXCLUSIVE;
+
+	mutex_lock(&local->chanctx_mtx);
+	ret = ieee80211_check_combinations(sdata, &params->chandef, chanmode,
+					   radar_detect_width);
+	mutex_unlock(&local->chanctx_mtx);
+	if (ret < 0)
+		return ret;
 
 	if (params->bssid) {
 		memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN);
@@ -1202,11 +1675,13 @@ int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
 
 	sdata->u.ibss.privacy = params->privacy;
 	sdata->u.ibss.control_port = params->control_port;
+	sdata->u.ibss.userspace_handles_dfs = params->userspace_handles_dfs;
 	sdata->u.ibss.basic_rates = params->basic_rates;
+	sdata->u.ibss.last_scan_completed = jiffies;
 
 	/* fix basic_rates if channel does not support these rates */
 	rate_flags = ieee80211_chandef_rate_flags(&params->chandef);
-	sband = sdata->local->hw.wiphy->bands[params->chandef.chan->band];
+	sband = local->hw.wiphy->bands[params->chandef.chan->band];
 	for (i = 0; i < sband->n_bitrates; i++) {
 		if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
 			sdata->u.ibss.basic_rates &= ~BIT(i);
@@ -1255,9 +1730,9 @@ int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
 	ieee80211_bss_info_change_notify(sdata, changed);
 
 	sdata->smps_mode = IEEE80211_SMPS_OFF;
-	sdata->needed_rx_chains = sdata->local->rx_chains;
+	sdata->needed_rx_chains = local->rx_chains;
 
-	ieee80211_queue_work(&sdata->local->hw, &sdata->work);
+	ieee80211_queue_work(&local->hw, &sdata->work);
 
 	return 0;
 }
@@ -1265,73 +1740,19 @@ int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
 int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata)
 {
 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
-	struct ieee80211_local *local = sdata->local;
-	struct cfg80211_bss *cbss;
-	u16 capability;
-	int active_ibss;
-	struct sta_info *sta;
-	struct beacon_data *presp;
-
-	active_ibss = ieee80211_sta_active_ibss(sdata);
-
-	if (!active_ibss && !is_zero_ether_addr(ifibss->bssid)) {
-		capability = WLAN_CAPABILITY_IBSS;
 
-		if (ifibss->privacy)
-			capability |= WLAN_CAPABILITY_PRIVACY;
-
-		cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->chandef.chan,
-					ifibss->bssid, ifibss->ssid,
-					ifibss->ssid_len, WLAN_CAPABILITY_IBSS |
-					WLAN_CAPABILITY_PRIVACY,
-					capability);
-
-		if (cbss) {
-			cfg80211_unlink_bss(local->hw.wiphy, cbss);
-			cfg80211_put_bss(local->hw.wiphy, cbss);
-		}
-	}
-
-	ifibss->state = IEEE80211_IBSS_MLME_SEARCH;
-	memset(ifibss->bssid, 0, ETH_ALEN);
+	ieee80211_ibss_disconnect(sdata);
 	ifibss->ssid_len = 0;
-
-	sta_info_flush(sdata);
-
-	spin_lock_bh(&ifibss->incomplete_lock);
-	while (!list_empty(&ifibss->incomplete_stations)) {
-		sta = list_first_entry(&ifibss->incomplete_stations,
-				       struct sta_info, list);
-		list_del(&sta->list);
-		spin_unlock_bh(&ifibss->incomplete_lock);
-
-		sta_info_free(local, sta);
-		spin_lock_bh(&ifibss->incomplete_lock);
-	}
-	spin_unlock_bh(&ifibss->incomplete_lock);
-
-	netif_carrier_off(sdata->dev);
+	memset(ifibss->bssid, 0, ETH_ALEN);
 
 	/* remove beacon */
 	kfree(sdata->u.ibss.ie);
-	presp = rcu_dereference_protected(ifibss->presp,
-					  lockdep_is_held(&sdata->wdev.mtx));
-	RCU_INIT_POINTER(sdata->u.ibss.presp, NULL);
 
 	/* on the next join, re-program HT parameters */
 	memset(&ifibss->ht_capa, 0, sizeof(ifibss->ht_capa));
 	memset(&ifibss->ht_capa_mask, 0, sizeof(ifibss->ht_capa_mask));
 
-	sdata->vif.bss_conf.ibss_joined = false;
-	sdata->vif.bss_conf.ibss_creator = false;
-	sdata->vif.bss_conf.enable_beacon = false;
-	sdata->vif.bss_conf.ssid_len = 0;
-	clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state);
-	ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED |
-						BSS_CHANGED_IBSS);
-	ieee80211_vif_release_channel(sdata);
 	synchronize_rcu();
-	kfree(presp);
 
 	skb_queue_purge(&sdata->skb_queue);