Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1878 insertions, 0 deletions

diff --git a/net/mac80211/ibss.c b/net/mac80211/ibss.c
new file mode 100644
index 000000000..fa13eef25
--- /dev/null
+++ b/net/mac80211/ibss.c
@@ -0,0 +1,1878 @@
+/*
+ * IBSS mode implementation
+ * Copyright 2003-2008, Jouni Malinen <j@w1.fi>
+ * Copyright 2004, Instant802 Networks, Inc.
+ * Copyright 2005, Devicescape Software, Inc.
+ * Copyright 2006-2007	Jiri Benc <jbenc@suse.cz>
+ * Copyright 2007, Michael Wu <flamingice@sourmilk.net>
+ * Copyright 2009, Johannes Berg <johannes@sipsolutions.net>
+ * Copyright 2013-2014  Intel Mobile Communications GmbH
+ * Copyright(c) 2016 Intel Deutschland GmbH
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include <linux/if_ether.h>
+#include <linux/skbuff.h>
+#include <linux/if_arp.h>
+#include <linux/etherdevice.h>
+#include <linux/rtnetlink.h>
+#include <net/mac80211.h>
+
+#include "ieee80211_i.h"
+#include "driver-ops.h"
+#include "rate.h"
+
+#define IEEE80211_SCAN_INTERVAL (2 * HZ)
+#define IEEE80211_IBSS_JOIN_TIMEOUT (7 * HZ)
+
+#define IEEE80211_IBSS_MERGE_INTERVAL (30 * HZ)
+#define IEEE80211_IBSS_INACTIVITY_LIMIT (60 * HZ)
+#define IEEE80211_IBSS_RSN_INACTIVITY_LIMIT (10 * HZ)
+
+#define IEEE80211_IBSS_MAX_STA_ENTRIES 128
+
+static struct beacon_data *
+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,
+			   struct cfg80211_csa_settings *csa_settings)
+{
+	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
+	struct ieee80211_local *local = sdata->local;
+	int rates_n = 0, i, ri;
+	struct ieee80211_mgmt *mgmt;
+	u8 *pos;
+	struct ieee80211_supported_band *sband;
+	u32 rate_flags, rates = 0, rates_added = 0;
+	struct beacon_data *presp;
+	int frame_len;
+	int shift;
+
+	/* Build IBSS probe response */
+	frame_len = sizeof(struct ieee80211_hdr_3addr) +
+		    12 /* struct ieee80211_mgmt.u.beacon */ +
+		    2 + IEEE80211_MAX_SSID_LEN /* max SSID */ +
+		    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) +
+		    2 + sizeof(struct ieee80211_vht_cap) +
+		    2 + sizeof(struct ieee80211_vht_operation) +
+		    ifibss->ie_len;
+	presp = kzalloc(sizeof(*presp) + frame_len, GFP_KERNEL);
+	if (!presp)
+		return NULL;
+
+	presp->head = (void *)(presp + 1);
+
+	mgmt = (void *) presp->head;
+	mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
+					  IEEE80211_STYPE_PROBE_RESP);
+	eth_broadcast_addr(mgmt->da);
+	memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
+	memcpy(mgmt->bssid, ifibss->bssid, ETH_ALEN);
+	mgmt->u.beacon.beacon_int = cpu_to_le16(beacon_int);
+	mgmt->u.beacon.timestamp = cpu_to_le64(tsf);
+	mgmt->u.beacon.capab_info = cpu_to_le16(capability);
+
+	pos = (u8 *)mgmt + offsetof(struct ieee80211_mgmt, u.beacon.variable);
+
+	*pos++ = WLAN_EID_SSID;
+	*pos++ = ifibss->ssid_len;
+	memcpy(pos, ifibss->ssid, ifibss->ssid_len);
+	pos += ifibss->ssid_len;
+
+	sband = local->hw.wiphy->bands[chandef->chan->band];
+	rate_flags = ieee80211_chandef_rate_flags(chandef);
+	shift = ieee80211_chandef_get_shift(chandef);
+	rates_n = 0;
+	if (have_higher_than_11mbit)
+		*have_higher_than_11mbit = false;
+
+	for (i = 0; i < sband->n_bitrates; i++) {
+		if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
+			continue;
+		if (sband->bitrates[i].bitrate > 110 &&
+		    have_higher_than_11mbit)
+			*have_higher_than_11mbit = true;
+
+		rates |= BIT(i);
+		rates_n++;
+	}
+
+	*pos++ = WLAN_EID_SUPP_RATES;
+	*pos++ = min_t(int, 8, rates_n);
+	for (ri = 0; ri < sband->n_bitrates; ri++) {
+		int rate = DIV_ROUND_UP(sband->bitrates[ri].bitrate,
+					5 * (1 << shift));
+		u8 basic = 0;
+		if (!(rates & BIT(ri)))
+			continue;
+
+		if (basic_rates & BIT(ri))
+			basic = 0x80;
+		*pos++ = basic | (u8) rate;
+		if (++rates_added == 8) {
+			ri++; /* continue at next rate for EXT_SUPP_RATES */
+			break;
+		}
+	}
+
+	if (sband->band == NL80211_BAND_2GHZ) {
+		*pos++ = WLAN_EID_DS_PARAMS;
+		*pos++ = 1;
+		*pos++ = ieee80211_frequency_to_channel(
+				chandef->chan->center_freq);
+	}
+
+	*pos++ = WLAN_EID_IBSS_PARAMS;
+	*pos++ = 2;
+	/* FIX: set ATIM window based on scan results */
+	*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);
+		presp->csa_counter_offsets[0] = (pos - presp->head);
+		*pos++ = csa_settings->count;
+		presp->csa_current_counter = csa_settings->count;
+	}
+
+	/* put the remaining rates in WLAN_EID_EXT_SUPP_RATES */
+	if (rates_n > 8) {
+		*pos++ = WLAN_EID_EXT_SUPP_RATES;
+		*pos++ = rates_n - 8;
+		for (; ri < sband->n_bitrates; ri++) {
+			int rate = DIV_ROUND_UP(sband->bitrates[ri].bitrate,
+						5 * (1 << shift));
+			u8 basic = 0;
+			if (!(rates & BIT(ri)))
+				continue;
+
+			if (basic_rates & BIT(ri))
+				basic = 0x80;
+			*pos++ = basic | (u8) rate;
+		}
+	}
+
+	if (ifibss->ie_len) {
+		memcpy(pos, ifibss->ie, ifibss->ie_len);
+		pos += ifibss->ie_len;
+	}
+
+	/* add HT capability and information IEs */
+	if (chandef->width != NL80211_CHAN_WIDTH_20_NOHT &&
+	    chandef->width != NL80211_CHAN_WIDTH_5 &&
+	    chandef->width != NL80211_CHAN_WIDTH_10 &&
+	    sband->ht_cap.ht_supported) {
+		struct ieee80211_sta_ht_cap ht_cap;
+
+		memcpy(&ht_cap, &sband->ht_cap, sizeof(ht_cap));
+		ieee80211_apply_htcap_overrides(sdata, &ht_cap);
+
+		pos = ieee80211_ie_build_ht_cap(pos, &ht_cap, ht_cap.cap);
+		/*
+		 * Note: According to 802.11n-2009 9.13.3.1, HT Protection
+		 * field and RIFS Mode are reserved in IBSS mode, therefore
+		 * keep them at 0
+		 */
+		pos = ieee80211_ie_build_ht_oper(pos, &sband->ht_cap,
+						 chandef, 0, false);
+
+		/* add VHT capability and information IEs */
+		if (chandef->width != NL80211_CHAN_WIDTH_20 &&
+		    chandef->width != NL80211_CHAN_WIDTH_40 &&
+		    sband->vht_cap.vht_supported) {
+			pos = ieee80211_ie_build_vht_cap(pos, &sband->vht_cap,
+							 sband->vht_cap.cap);
+			pos = ieee80211_ie_build_vht_oper(pos, &sband->vht_cap,
+							  chandef);
+		}
+	}
+
+	if (local->hw.queues >= IEEE80211_NUM_ACS)
+		pos = ieee80211_add_wmm_info_ie(pos, 0); /* U-APSD not in use */
+
+	presp->head_len = pos - presp->head;
+	if (WARN_ON(presp->head_len > frame_len))
+		goto error;
+
+	return presp;
+error:
+	kfree(presp);
+	return NULL;
+}
+
+static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
+				      const u8 *bssid, const int beacon_int,
+				      struct cfg80211_chan_def *req_chandef,
+				      const u32 basic_rates,
+				      const u16 capability, u64 tsf,
+				      bool creator)
+{
+	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
+	struct ieee80211_local *local = sdata->local;
+	struct ieee80211_mgmt *mgmt;
+	struct cfg80211_bss *bss;
+	u32 bss_change;
+	struct cfg80211_chan_def chandef;
+	struct ieee80211_channel *chan;
+	struct beacon_data *presp;
+	struct cfg80211_inform_bss bss_meta = {};
+	bool have_higher_than_11mbit;
+	bool radar_required;
+	int err;
+
+	sdata_assert_lock(sdata);
+
+	/* Reset own TSF to allow time synchronization work. */
+	drv_reset_tsf(local, sdata);
+
+	if (!ether_addr_equal(ifibss->bssid, bssid))
+		sta_info_flush(sdata);
+
+	/* if merging, indicate to driver that we leave the old IBSS */
+	if (sdata->vif.bss_conf.ibss_joined) {
+		sdata->vif.bss_conf.ibss_joined = false;
+		sdata->vif.bss_conf.ibss_creator = false;
+		sdata->vif.bss_conf.enable_beacon = false;
+		netif_carrier_off(sdata->dev);
+		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_INIT_POINTER(ifibss->presp, NULL);
+	if (presp)
+		kfree_rcu(presp, rcu_head);
+
+	/* 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,
+				     NL80211_IFTYPE_ADHOC)) {
+		if (chandef.width == NL80211_CHAN_WIDTH_5 ||
+		    chandef.width == NL80211_CHAN_WIDTH_10 ||
+		    chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
+		    chandef.width == NL80211_CHAN_WIDTH_20) {
+			sdata_info(sdata,
+				   "Failed to join IBSS, beacons forbidden\n");
+			return;
+		}
+		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;
+		}
+	}
+
+	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);
+
+	presp = ieee80211_ibss_build_presp(sdata, beacon_int, basic_rates,
+					   capability, tsf, &chandef,
+					   &have_higher_than_11mbit, NULL);
+	if (!presp)
+		return;
+
+	rcu_assign_pointer(ifibss->presp, presp);
+	mgmt = (void *)presp->head;
+
+	sdata->vif.bss_conf.enable_beacon = true;
+	sdata->vif.bss_conf.beacon_int = beacon_int;
+	sdata->vif.bss_conf.basic_rates = basic_rates;
+	sdata->vif.bss_conf.ssid_len = ifibss->ssid_len;
+	memcpy(sdata->vif.bss_conf.ssid, ifibss->ssid, ifibss->ssid_len);
+	bss_change = BSS_CHANGED_BEACON_INT;
+	bss_change |= ieee80211_reset_erp_info(sdata);
+	bss_change |= BSS_CHANGED_BSSID;
+	bss_change |= BSS_CHANGED_BEACON;
+	bss_change |= BSS_CHANGED_BEACON_ENABLED;
+	bss_change |= BSS_CHANGED_BASIC_RATES;
+	bss_change |= BSS_CHANGED_HT;
+	bss_change |= BSS_CHANGED_IBSS;
+	bss_change |= BSS_CHANGED_SSID;
+
+	/*
+	 * In 5 GHz/802.11a, we can always use short slot time.
+	 * (IEEE 802.11-2012 18.3.8.7)
+	 *
+	 * In 2.4GHz, we must always use long slots in IBSS for compatibility
+	 * reasons.
+	 * (IEEE 802.11-2012 19.4.5)
+	 *
+	 * HT follows these specifications (IEEE 802.11-2012 20.3.18)
+	 */
+	sdata->vif.bss_conf.use_short_slot = chan->band == NL80211_BAND_5GHZ;
+	bss_change |= BSS_CHANGED_ERP_SLOT;
+
+	/* cf. IEEE 802.11 9.2.12 */
+	if (chan->band == NL80211_BAND_2GHZ && have_higher_than_11mbit)
+		sdata->flags |= IEEE80211_SDATA_OPERATING_GMODE;
+	else
+		sdata->flags &= ~IEEE80211_SDATA_OPERATING_GMODE;
+
+	ieee80211_set_wmm_default(sdata, true, false);
+
+	sdata->vif.bss_conf.ibss_joined = true;
+	sdata->vif.bss_conf.ibss_creator = creator;
+
+	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,
+		  round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
+
+	bss_meta.chan = chan;
+	bss_meta.scan_width = cfg80211_chandef_to_scan_width(&chandef);
+	bss = cfg80211_inform_bss_frame_data(local->hw.wiphy, &bss_meta, mgmt,
+					     presp->head_len, GFP_KERNEL);
+
+	cfg80211_put_bss(local->hw.wiphy, bss);
+	netif_carrier_on(sdata->dev);
+	cfg80211_ibss_joined(sdata->dev, ifibss->bssid, chan, GFP_KERNEL);
+}
+
+static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
+				    struct ieee80211_bss *bss)
+{
+	struct cfg80211_bss *cbss =
+		container_of((void *)bss, struct cfg80211_bss, priv);
+	struct ieee80211_supported_band *sband;
+	struct cfg80211_chan_def chandef;
+	u32 basic_rates;
+	int i, j;
+	u16 beacon_int = cbss->beacon_interval;
+	const struct cfg80211_bss_ies *ies;
+	enum nl80211_channel_type chan_type;
+	u64 tsf;
+	u32 rate_flags;
+	int shift;
+
+	sdata_assert_lock(sdata);
+
+	if (beacon_int < 10)
+		beacon_int = 10;
+
+	switch (sdata->u.ibss.chandef.width) {
+	case NL80211_CHAN_WIDTH_20_NOHT:
+	case NL80211_CHAN_WIDTH_20:
+	case NL80211_CHAN_WIDTH_40:
+		chan_type = cfg80211_get_chandef_type(&sdata->u.ibss.chandef);
+		cfg80211_chandef_create(&chandef, cbss->channel, chan_type);
+		break;
+	case NL80211_CHAN_WIDTH_5:
+	case NL80211_CHAN_WIDTH_10:
+		cfg80211_chandef_create(&chandef, cbss->channel,
+					NL80211_CHAN_NO_HT);
+		chandef.width = sdata->u.ibss.chandef.width;
+		break;
+	case NL80211_CHAN_WIDTH_80:
+	case NL80211_CHAN_WIDTH_80P80:
+	case NL80211_CHAN_WIDTH_160:
+		chandef = sdata->u.ibss.chandef;
+		chandef.chan = cbss->channel;
+		break;
+	default:
+		/* fall back to 20 MHz for unsupported modes */
+		cfg80211_chandef_create(&chandef, cbss->channel,
+					NL80211_CHAN_NO_HT);
+		break;
+	}
+
+	sband = sdata->local->hw.wiphy->bands[cbss->channel->band];
+	rate_flags = ieee80211_chandef_rate_flags(&sdata->u.ibss.chandef);
+	shift = ieee80211_vif_get_shift(&sdata->vif);
+
+	basic_rates = 0;
+
+	for (i = 0; i < bss->supp_rates_len; i++) {
+		int rate = bss->supp_rates[i] & 0x7f;
+		bool is_basic = !!(bss->supp_rates[i] & 0x80);
+
+		for (j = 0; j < sband->n_bitrates; j++) {
+			int brate;
+			if ((rate_flags & sband->bitrates[j].flags)
+			    != rate_flags)
+				continue;
+
+			brate = DIV_ROUND_UP(sband->bitrates[j].bitrate,
+					     5 * (1 << shift));
+			if (brate == rate) {
+				if (is_basic)
+					basic_rates |= BIT(j);
+				break;
+			}
+		}
+	}
+
+	rcu_read_lock();
+	ies = rcu_dereference(cbss->ies);
+	tsf = ies->tsf;
+	rcu_read_unlock();
+
+	__ieee80211_sta_join_ibss(sdata, cbss->bssid,
+				  beacon_int,
+				  &chandef,
+				  basic_rates,
+				  cbss->capability,
+				  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 = WLAN_CAPABILITY_IBSS;
+	u64 tsf;
+	int ret = 0;
+
+	sdata_assert_lock(sdata);
+
+	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, IEEE80211_BSS_TYPE_IBSS,
+				IEEE80211_PRIVACY(ifibss->privacy));
+
+	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;
+
+	sdata_assert_lock(sdata);
+
+	/* update cfg80211 bss information with the new channel */
+	if (!is_zero_ether_addr(ifibss->bssid)) {
+		cbss = cfg80211_get_bss(sdata->local->hw.wiphy,
+					ifibss->chandef.chan,
+					ifibss->bssid, ifibss->ssid,
+					ifibss->ssid_len,
+					IEEE80211_BSS_TYPE_IBSS,
+					IEEE80211_PRIVACY(ifibss->privacy));
+		/* 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)
+{
+	struct ieee80211_sub_if_data *sdata = sta->sdata;
+	u8 addr[ETH_ALEN];
+
+	memcpy(addr, sta->sta.addr, ETH_ALEN);
+
+	ibss_dbg(sdata, "Adding new IBSS station %pM\n", addr);
+
+	sta_info_pre_move_state(sta, IEEE80211_STA_AUTH);
+	sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC);
+	/* authorize the station only if the network is not RSN protected. If
+	 * not wait for the userspace to authorize it */
+	if (!sta->sdata->u.ibss.control_port)
+		sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED);
+
+	rate_control_rate_init(sta);
+
+	/* If it fails, maybe we raced another insertion? */
+	if (sta_info_insert_rcu(sta))
+		return sta_info_get(sdata, addr);
+	return sta;
+}
+
+static struct sta_info *
+ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata, const u8 *bssid,
+		       const u8 *addr, u32 supp_rates)
+	__acquires(RCU)
+{
+	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
+	struct ieee80211_local *local = sdata->local;
+	struct sta_info *sta;
+	struct ieee80211_chanctx_conf *chanctx_conf;
+	struct ieee80211_supported_band *sband;
+	enum nl80211_bss_scan_width scan_width;
+	int band;
+
+	/*
+	 * XXX: Consider removing the least recently used entry and
+	 * 	allow new one to be added.
+	 */
+	if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
+		net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
+				    sdata->name, addr);
+		rcu_read_lock();
+		return NULL;
+	}
+
+	if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) {
+		rcu_read_lock();
+		return NULL;
+	}
+
+	if (!ether_addr_equal(bssid, sdata->u.ibss.bssid)) {
+		rcu_read_lock();
+		return NULL;
+	}
+
+	rcu_read_lock();
+	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
+	if (WARN_ON_ONCE(!chanctx_conf))
+		return NULL;
+	band = chanctx_conf->def.chan->band;
+	scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def);
+	rcu_read_unlock();
+
+	sta = sta_info_alloc(sdata, addr, GFP_KERNEL);
+	if (!sta) {
+		rcu_read_lock();
+		return NULL;
+	}
+
+	/* make sure mandatory rates are always added */
+	sband = local->hw.wiphy->bands[band];
+	sta->sta.supp_rates[band] = supp_rates |
+			ieee80211_mandatory_rates(sband, scan_width);
+
+	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) {
+		unsigned long last_active = ieee80211_sta_last_active(sta);
+
+		if (sta->sdata == sdata &&
+		    time_is_after_jiffies(last_active +
+					  IEEE80211_IBSS_MERGE_INTERVAL)) {
+			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;
+
+	if (!is_zero_ether_addr(ifibss->bssid)) {
+		cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->chandef.chan,
+					ifibss->bssid, ifibss->ssid,
+					ifibss->ssid_len,
+					IEEE80211_BSS_TYPE_IBSS,
+					IEEE80211_PRIVACY(ifibss->privacy));
+
+		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));
+	err = ieee80211_parse_ch_switch_ie(sdata, elems,
+					   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)
+{
+	u16 reason = le16_to_cpu(mgmt->u.deauth.reason_code);
+
+	if (len < IEEE80211_DEAUTH_FRAME_LEN)
+		return;
+
+	ibss_dbg(sdata, "RX DeAuth SA=%pM DA=%pM\n", mgmt->sa, mgmt->da);
+	ibss_dbg(sdata, "\tBSSID=%pM (reason: %d)\n", mgmt->bssid, reason);
+	sta_info_destroy_addr(sdata, mgmt->sa);
+}
+
+static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata,
+					struct ieee80211_mgmt *mgmt,
+					size_t len)
+{
+	u16 auth_alg, auth_transaction;
+
+	sdata_assert_lock(sdata);
+
+	if (len < 24 + 6)
+		return;
+
+	auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg);
+	auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction);
+
+	ibss_dbg(sdata, "RX Auth SA=%pM DA=%pM\n", mgmt->sa, mgmt->da);
+	ibss_dbg(sdata, "\tBSSID=%pM (auth_transaction=%d)\n",
+		 mgmt->bssid, auth_transaction);
+
+	if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1)
+		return;
+
+	/*
+	 * IEEE 802.11 standard does not require authentication in IBSS
+	 * networks and most implementations do not seem to use it.
+	 * However, try to reply to authentication attempts if someone
+	 * has actually implemented this.
+	 */
+	ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, 0, NULL, 0,
+			    mgmt->sa, sdata->u.ibss.bssid, NULL, 0, 0, 0);
+}
+
+static void ieee80211_update_sta_info(struct ieee80211_sub_if_data *sdata,
+				      struct ieee80211_mgmt *mgmt, size_t len,
+				      struct ieee80211_rx_status *rx_status,
+				      struct ieee802_11_elems *elems,
+				      struct ieee80211_channel *channel)
+{
+	struct sta_info *sta;
+	enum nl80211_band band = rx_status->band;
+	enum nl80211_bss_scan_width scan_width;
+	struct ieee80211_local *local = sdata->local;
+	struct ieee80211_supported_band *sband;
+	bool rates_updated = false;
+	u32 supp_rates = 0;
+
+	if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
+		return;
+
+	if (!ether_addr_equal(mgmt->bssid, sdata->u.ibss.bssid))
+		return;
+
+	sband = local->hw.wiphy->bands[band];
+	if (WARN_ON(!sband))
+		return;
+
+	rcu_read_lock();
+	sta = sta_info_get(sdata, mgmt->sa);
+
+	if (elems->supp_rates) {
+		supp_rates = ieee80211_sta_get_rates(sdata, elems,
+						     band, NULL);
+		if (sta) {
+			u32 prev_rates;
+
+			prev_rates = sta->sta.supp_rates[band];
+			/* make sure mandatory rates are always added */
+			scan_width = NL80211_BSS_CHAN_WIDTH_20;
+			if (rx_status->bw == RATE_INFO_BW_5)
+				scan_width = NL80211_BSS_CHAN_WIDTH_5;
+			else if (rx_status->bw == RATE_INFO_BW_10)
+				scan_width = NL80211_BSS_CHAN_WIDTH_10;
+
+			sta->sta.supp_rates[band] = supp_rates |
+				ieee80211_mandatory_rates(sband, scan_width);
+			if (sta->sta.supp_rates[band] != prev_rates) {
+				ibss_dbg(sdata,
+					 "updated supp_rates set for %pM based on beacon/probe_resp (0x%x -> 0x%x)\n",
+					 sta->sta.addr, prev_rates,
+					 sta->sta.supp_rates[band]);
+				rates_updated = true;
+			}
+		} else {
+			rcu_read_unlock();
+			sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid,
+						     mgmt->sa, supp_rates);
+		}
+	}
+
+	if (sta && !sta->sta.wme &&
+	    elems->wmm_info && local->hw.queues >= IEEE80211_NUM_ACS) {
+		sta->sta.wme = true;
+		ieee80211_check_fast_xmit(sta);
+	}
+
+	if (sta && elems->ht_operation && elems->ht_cap_elem &&
+	    sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_20_NOHT &&
+	    sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_5 &&
+	    sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_10) {
+		/* we both use HT */
+		struct ieee80211_ht_cap htcap_ie;
+		struct cfg80211_chan_def chandef;
+		enum ieee80211_sta_rx_bandwidth bw = sta->sta.bandwidth;
+
+		cfg80211_chandef_create(&chandef, channel, NL80211_CHAN_NO_HT);
+		ieee80211_chandef_ht_oper(elems->ht_operation, &chandef);
+
+		memcpy(&htcap_ie, elems->ht_cap_elem, sizeof(htcap_ie));
+		rates_updated |= ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband,
+								   &htcap_ie,
+								   sta);
+
+		if (elems->vht_operation && elems->vht_cap_elem &&
+		    sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_20 &&
+		    sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_40) {
+			/* we both use VHT */
+			struct ieee80211_vht_cap cap_ie;
+			struct ieee80211_sta_vht_cap cap = sta->sta.vht_cap;
+
+			ieee80211_chandef_vht_oper(elems->vht_operation,
+						   &chandef);
+			memcpy(&cap_ie, elems->vht_cap_elem, sizeof(cap_ie));
+			ieee80211_vht_cap_ie_to_sta_vht_cap(sdata, sband,
+							    &cap_ie, sta);
+			if (memcmp(&cap, &sta->sta.vht_cap, sizeof(cap)))
+				rates_updated |= true;
+		}
+
+		if (bw != sta->sta.bandwidth)
+			rates_updated |= true;
+
+		if (!cfg80211_chandef_compatible(&sdata->u.ibss.chandef,
+						 &chandef))
+			WARN_ON_ONCE(1);
+	}
+
+	if (sta && rates_updated) {
+		u32 changed = IEEE80211_RC_SUPP_RATES_CHANGED;
+		u8 rx_nss = sta->sta.rx_nss;
+
+		/* Force rx_nss recalculation */
+		sta->sta.rx_nss = 0;
+		rate_control_rate_init(sta);
+		if (sta->sta.rx_nss != rx_nss)
+			changed |= IEEE80211_RC_NSS_CHANGED;
+
+		drv_sta_rc_update(local, sdata, &sta->sta, changed);
+	}
+
+	rcu_read_unlock();
+}
+
+static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
+				  struct ieee80211_mgmt *mgmt, size_t len,
+				  struct ieee80211_rx_status *rx_status,
+				  struct ieee802_11_elems *elems)
+{
+	struct ieee80211_local *local = sdata->local;
+	struct cfg80211_bss *cbss;
+	struct ieee80211_bss *bss;
+	struct ieee80211_channel *channel;
+	u64 beacon_timestamp, rx_timestamp;
+	u32 supp_rates = 0;
+	enum nl80211_band band = rx_status->band;
+
+	channel = ieee80211_get_channel(local->hw.wiphy, rx_status->freq);
+	if (!channel)
+		return;
+
+	ieee80211_update_sta_info(sdata, mgmt, len, rx_status, elems, channel);
+
+	bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems,
+					channel);
+	if (!bss)
+		return;
+
+	cbss = container_of((void *)bss, struct cfg80211_bss, priv);
+
+	/* same for beacon and probe response */
+	beacon_timestamp = le64_to_cpu(mgmt->u.beacon.timestamp);
+
+	/* check if we need to merge IBSS */
+
+	/* not an IBSS */
+	if (!(cbss->capability & WLAN_CAPABILITY_IBSS))
+		goto put_bss;
+
+	/* different channel */
+	if (sdata->u.ibss.fixed_channel &&
+	    sdata->u.ibss.chandef.chan != cbss->channel)
+		goto put_bss;
+
+	/* different SSID */
+	if (elems->ssid_len != sdata->u.ibss.ssid_len ||
+	    memcmp(elems->ssid, sdata->u.ibss.ssid,
+				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 =
+			ieee80211_calculate_rx_timestamp(local, rx_status,
+							 len + FCS_LEN, 24);
+	} else {
+		/*
+		 * second best option: get current TSF
+		 * (will return -1 if not supported)
+		 */
+		rx_timestamp = drv_get_tsf(local, sdata);
+	}
+
+	ibss_dbg(sdata, "RX beacon SA=%pM BSSID=%pM TSF=0x%llx\n",
+		 mgmt->sa, mgmt->bssid,
+		 (unsigned long long)rx_timestamp);
+	ibss_dbg(sdata, "\tBCN=0x%llx diff=%lld @%lu\n",
+		 (unsigned long long)beacon_timestamp,
+		 (unsigned long long)(rx_timestamp - beacon_timestamp),
+		 jiffies);
+
+	if (beacon_timestamp > rx_timestamp) {
+		ibss_dbg(sdata,
+			 "beacon TSF higher than local TSF - IBSS merge with BSSID %pM\n",
+			 mgmt->bssid);
+		ieee80211_sta_join_ibss(sdata, bss);
+		supp_rates = ieee80211_sta_get_rates(sdata, elems, band, NULL);
+		ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
+				       supp_rates);
+		rcu_read_unlock();
+	}
+
+ put_bss:
+	ieee80211_rx_bss_put(local, bss);
+}
+
+void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata,
+			      const u8 *bssid, const u8 *addr,
+			      u32 supp_rates)
+{
+	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
+	struct ieee80211_local *local = sdata->local;
+	struct sta_info *sta;
+	struct ieee80211_chanctx_conf *chanctx_conf;
+	struct ieee80211_supported_band *sband;
+	enum nl80211_bss_scan_width scan_width;
+	int band;
+
+	/*
+	 * XXX: Consider removing the least recently used entry and
+	 * 	allow new one to be added.
+	 */
+	if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
+		net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
+				    sdata->name, addr);
+		return;
+	}
+
+	if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH)
+		return;
+
+	if (!ether_addr_equal(bssid, sdata->u.ibss.bssid))
+		return;
+
+	rcu_read_lock();
+	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
+	if (WARN_ON_ONCE(!chanctx_conf)) {
+		rcu_read_unlock();
+		return;
+	}
+	band = chanctx_conf->def.chan->band;
+	scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def);
+	rcu_read_unlock();
+
+	sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
+	if (!sta)
+		return;
+
+	/* make sure mandatory rates are always added */
+	sband = local->hw.wiphy->bands[band];
+	sta->sta.supp_rates[band] = supp_rates |
+			ieee80211_mandatory_rates(sband, scan_width);
+
+	spin_lock(&ifibss->incomplete_lock);
+	list_add(&sta->list, &ifibss->incomplete_stations);
+	spin_unlock(&ifibss->incomplete_lock);
+	ieee80211_queue_work(&local->hw, &sdata->work);
+}
+
+static void ieee80211_ibss_sta_expire(struct ieee80211_sub_if_data *sdata)
+{
+	struct ieee80211_local *local = sdata->local;
+	struct sta_info *sta, *tmp;
+	unsigned long exp_time = IEEE80211_IBSS_INACTIVITY_LIMIT;
+	unsigned long exp_rsn = IEEE80211_IBSS_RSN_INACTIVITY_LIMIT;
+
+	mutex_lock(&local->sta_mtx);
+
+	list_for_each_entry_safe(sta, tmp, &local->sta_list, list) {
+		unsigned long last_active = ieee80211_sta_last_active(sta);
+
+		if (sdata != sta->sdata)
+			continue;
+
+		if (time_is_before_jiffies(last_active + exp_time) ||
+		    (time_is_before_jiffies(last_active + exp_rsn) &&
+		     sta->sta_state != IEEE80211_STA_AUTHORIZED)) {
+			sta_dbg(sta->sdata, "expiring inactive %sSTA %pM\n",
+				sta->sta_state != IEEE80211_STA_AUTHORIZED ?
+				"not authorized " : "", sta->sta.addr);
+
+			WARN_ON(__sta_info_destroy(sta));
+		}
+	}
+
+	mutex_unlock(&local->sta_mtx);
+}
+
+/*
+ * This function is called with state == IEEE80211_IBSS_MLME_JOINED
+ */
+
+static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata)
+{
+	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
+	enum nl80211_bss_scan_width scan_width;
+
+	sdata_assert_lock(sdata);
+
+	mod_timer(&ifibss->timer,
+		  round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
+
+	ieee80211_ibss_sta_expire(sdata);
+
+	if (time_before(jiffies, ifibss->last_scan_completed +
+		       IEEE80211_IBSS_MERGE_INTERVAL))
+		return;
+
+	if (ieee80211_sta_active_ibss(sdata))
+		return;
+
+	if (ifibss->fixed_channel)
+		return;
+
+	sdata_info(sdata,
+		   "No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge)\n");
+
+	scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef);
+	ieee80211_request_ibss_scan(sdata, ifibss->ssid, ifibss->ssid_len,
+				    NULL, 0, scan_width);
+}
+
+static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata)
+{
+	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
+	u8 bssid[ETH_ALEN];
+	u16 capability;
+	int i;
+
+	sdata_assert_lock(sdata);
+
+	if (ifibss->fixed_bssid) {
+		memcpy(bssid, ifibss->bssid, ETH_ALEN);
+	} else {
+		/* Generate random, not broadcast, locally administered BSSID. Mix in
+		 * own MAC address to make sure that devices that do not have proper
+		 * random number generator get different BSSID. */
+		get_random_bytes(bssid, ETH_ALEN);
+		for (i = 0; i < ETH_ALEN; i++)
+			bssid[i] ^= sdata->vif.addr[i];
+		bssid[0] &= ~0x01;
+		bssid[0] |= 0x02;
+	}
+
+	sdata_info(sdata, "Creating new IBSS network, BSSID %pM\n", bssid);
+
+	capability = WLAN_CAPABILITY_IBSS;
+
+	if (ifibss->privacy)
+		capability |= WLAN_CAPABILITY_PRIVACY;
+
+	__ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int,
+				  &ifibss->chandef, ifibss->basic_rates,
+				  capability, 0, true);
+}
+
+static unsigned ibss_setup_channels(struct wiphy *wiphy,
+				    struct ieee80211_channel **channels,
+				    unsigned int channels_max,
+				    u32 center_freq, u32 width)
+{
+	struct ieee80211_channel *chan = NULL;
+	unsigned int n_chan = 0;
+	u32 start_freq, end_freq, freq;
+
+	if (width <= 20) {
+		start_freq = center_freq;
+		end_freq = center_freq;
+	} else {
+		start_freq = center_freq - width / 2 + 10;
+		end_freq = center_freq + width / 2 - 10;
+	}
+
+	for (freq = start_freq; freq <= end_freq; freq += 20) {
+		chan = ieee80211_get_channel(wiphy, freq);
+		if (!chan)
+			continue;
+		if (n_chan >= channels_max)
+			return n_chan;
+
+		channels[n_chan] = chan;
+		n_chan++;
+	}
+
+	return n_chan;
+}
+
+static unsigned int
+ieee80211_ibss_setup_scan_channels(struct wiphy *wiphy,
+				   const struct cfg80211_chan_def *chandef,
+				   struct ieee80211_channel **channels,
+				   unsigned int channels_max)
+{
+	unsigned int n_chan = 0;
+	u32 width, cf1, cf2 = 0;
+
+	switch (chandef->width) {
+	case NL80211_CHAN_WIDTH_40:
+		width = 40;
+		break;
+	case NL80211_CHAN_WIDTH_80P80:
+		cf2 = chandef->center_freq2;
+		/* fall through */
+	case NL80211_CHAN_WIDTH_80:
+		width = 80;
+		break;
+	case NL80211_CHAN_WIDTH_160:
+		width = 160;
+		break;
+	default:
+		width = 20;
+		break;
+	}
+
+	cf1 = chandef->center_freq1;
+
+	n_chan = ibss_setup_channels(wiphy, channels, channels_max, cf1, width);
+
+	if (cf2)
+		n_chan += ibss_setup_channels(wiphy, &channels[n_chan],
+					      channels_max - n_chan, cf2,
+					      width);
+
+	return n_chan;
+}
+
+/*
+ * This function is called with state == IEEE80211_IBSS_MLME_SEARCH
+ */
+
+static void ieee80211_sta_find_ibss(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 ieee80211_channel *chan = NULL;
+	const u8 *bssid = NULL;
+	enum nl80211_bss_scan_width scan_width;
+	int active_ibss;
+
+	sdata_assert_lock(sdata);
+
+	active_ibss = ieee80211_sta_active_ibss(sdata);
+	ibss_dbg(sdata, "sta_find_ibss (active_ibss=%d)\n", active_ibss);
+
+	if (active_ibss)
+		return;
+
+	if (ifibss->fixed_bssid)
+		bssid = ifibss->bssid;
+	if (ifibss->fixed_channel)
+		chan = ifibss->chandef.chan;
+	if (!is_zero_ether_addr(ifibss->bssid))
+		bssid = ifibss->bssid;
+	cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid,
+				ifibss->ssid, ifibss->ssid_len,
+				IEEE80211_BSS_TYPE_IBSS,
+				IEEE80211_PRIVACY(ifibss->privacy));
+
+	if (cbss) {
+		struct ieee80211_bss *bss;
+
+		bss = (void *)cbss->priv;
+		ibss_dbg(sdata,
+			 "sta_find_ibss: selected %pM current %pM\n",
+			 cbss->bssid, ifibss->bssid);
+		sdata_info(sdata,
+			   "Selected IBSS BSSID %pM based on configured SSID\n",
+			   cbss->bssid);
+
+		ieee80211_sta_join_ibss(sdata, bss);
+		ieee80211_rx_bss_put(local, bss);
+		return;
+	}
+
+	/* if a fixed bssid and a fixed freq have been provided create the IBSS
+	 * directly and do not waste time scanning
+	 */
+	if (ifibss->fixed_bssid && ifibss->fixed_channel) {
+		sdata_info(sdata, "Created IBSS using preconfigured BSSID %pM\n",
+			   bssid);
+		ieee80211_sta_create_ibss(sdata);
+		return;
+	}
+
+
+	ibss_dbg(sdata, "sta_find_ibss: did not try to join ibss\n");
+
+	/* Selected IBSS not found in current scan results - try to scan */
+	if (time_after(jiffies, ifibss->last_scan_completed +
+					IEEE80211_SCAN_INTERVAL)) {
+		struct ieee80211_channel *channels[8];
+		unsigned int num;
+
+		sdata_info(sdata, "Trigger new scan to find an IBSS to join\n");
+
+		scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef);
+
+		if (ifibss->fixed_channel) {
+			num = ieee80211_ibss_setup_scan_channels(local->hw.wiphy,
+								 &ifibss->chandef,
+								 channels,
+								 ARRAY_SIZE(channels));
+			ieee80211_request_ibss_scan(sdata, ifibss->ssid,
+						    ifibss->ssid_len, channels,
+						    num, scan_width);
+		} else {
+			ieee80211_request_ibss_scan(sdata, ifibss->ssid,
+						    ifibss->ssid_len, NULL,
+						    0, scan_width);
+		}
+	} else {
+		int interval = IEEE80211_SCAN_INTERVAL;
+
+		if (time_after(jiffies, ifibss->ibss_join_req +
+			       IEEE80211_IBSS_JOIN_TIMEOUT))
+			ieee80211_sta_create_ibss(sdata);
+
+		mod_timer(&ifibss->timer,
+			  round_jiffies(jiffies + interval));
+	}
+}
+
+static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata,
+					struct sk_buff *req)
+{
+	struct ieee80211_mgmt *mgmt = (void *)req->data;
+	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
+	struct ieee80211_local *local = sdata->local;
+	int tx_last_beacon, len = req->len;
+	struct sk_buff *skb;
+	struct beacon_data *presp;
+	u8 *pos, *end;
+
+	sdata_assert_lock(sdata);
+
+	presp = rcu_dereference_protected(ifibss->presp,
+					  lockdep_is_held(&sdata->wdev.mtx));
+
+	if (ifibss->state != IEEE80211_IBSS_MLME_JOINED ||
+	    len < 24 + 2 || !presp)
+		return;
+
+	tx_last_beacon = drv_tx_last_beacon(local);
+
+	ibss_dbg(sdata, "RX ProbeReq SA=%pM DA=%pM\n", mgmt->sa, mgmt->da);
+	ibss_dbg(sdata, "\tBSSID=%pM (tx_last_beacon=%d)\n",
+		 mgmt->bssid, tx_last_beacon);
+
+	if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da))
+		return;
+
+	if (!ether_addr_equal(mgmt->bssid, ifibss->bssid) &&
+	    !is_broadcast_ether_addr(mgmt->bssid))
+		return;
+
+	end = ((u8 *) mgmt) + len;
+	pos = mgmt->u.probe_req.variable;
+	if (pos[0] != WLAN_EID_SSID ||
+	    pos + 2 + pos[1] > end) {
+		ibss_dbg(sdata, "Invalid SSID IE in ProbeReq from %pM\n",
+			 mgmt->sa);
+		return;
+	}
+	if (pos[1] != 0 &&
+	    (pos[1] != ifibss->ssid_len ||
+	     memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) {
+		/* Ignore ProbeReq for foreign SSID */
+		return;
+	}
+
+	/* Reply with ProbeResp */
+	skb = dev_alloc_skb(local->tx_headroom + presp->head_len);
+	if (!skb)
+		return;
+
+	skb_reserve(skb, local->tx_headroom);
+	skb_put_data(skb, presp->head, presp->head_len);
+
+	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);
+}
+
+static
+void ieee80211_rx_mgmt_probe_beacon(struct ieee80211_sub_if_data *sdata,
+				    struct ieee80211_mgmt *mgmt, size_t len,
+				    struct ieee80211_rx_status *rx_status)
+{
+	size_t baselen;
+	struct ieee802_11_elems elems;
+
+	BUILD_BUG_ON(offsetof(typeof(mgmt->u.probe_resp), variable) !=
+		     offsetof(typeof(mgmt->u.beacon), variable));
+
+	/*
+	 * either beacon or probe_resp but the variable field is at the
+	 * same offset
+	 */
+	baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
+	if (baselen > len)
+		return;
+
+	ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
+			       false, &elems);
+
+	ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems);
+}
+
+void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
+				   struct sk_buff *skb)
+{
+	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;
+	fc = le16_to_cpu(mgmt->frame_control);
+
+	sdata_lock(sdata);
+
+	if (!sdata->u.ibss.ssid_len)
+		goto mgmt_out; /* not ready to merge yet */
+
+	switch (fc & IEEE80211_FCTL_STYPE) {
+	case IEEE80211_STYPE_PROBE_REQ:
+		ieee80211_rx_mgmt_probe_req(sdata, skb);
+		break;
+	case IEEE80211_STYPE_PROBE_RESP:
+	case IEEE80211_STYPE_BEACON:
+		ieee80211_rx_mgmt_probe_beacon(sdata, mgmt, skb->len,
+					       rx_status);
+		break;
+	case IEEE80211_STYPE_AUTH:
+		ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len);
+		break;
+	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:
+	sdata_unlock(sdata);
+}
+
+void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata)
+{
+	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
+	struct sta_info *sta;
+
+	sdata_lock(sdata);
+
+	/*
+	 * Work could be scheduled after scan or similar
+	 * when we aren't even joined (or trying) with a
+	 * network.
+	 */
+	if (!ifibss->ssid_len)
+		goto out;
+
+	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);
+
+		ieee80211_ibss_finish_sta(sta);
+		rcu_read_unlock();
+		spin_lock_bh(&ifibss->incomplete_lock);
+	}
+	spin_unlock_bh(&ifibss->incomplete_lock);
+
+	switch (ifibss->state) {
+	case IEEE80211_IBSS_MLME_SEARCH:
+		ieee80211_sta_find_ibss(sdata);
+		break;
+	case IEEE80211_IBSS_MLME_JOINED:
+		ieee80211_sta_merge_ibss(sdata);
+		break;
+	default:
+		WARN_ON(1);
+		break;
+	}
+
+ out:
+	sdata_unlock(sdata);
+}
+
+static void ieee80211_ibss_timer(struct timer_list *t)
+{
+	struct ieee80211_sub_if_data *sdata =
+		from_timer(sdata, t, u.ibss.timer);
+
+	ieee80211_queue_work(&sdata->local->hw, &sdata->work);
+}
+
+void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata)
+{
+	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
+
+	timer_setup(&ifibss->timer, ieee80211_ibss_timer, 0);
+	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 */
+void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local)
+{
+	struct ieee80211_sub_if_data *sdata;
+
+	mutex_lock(&local->iflist_mtx);
+	list_for_each_entry(sdata, &local->interfaces, list) {
+		if (!ieee80211_sdata_running(sdata))
+			continue;
+		if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
+			continue;
+		sdata->u.ibss.last_scan_completed = jiffies;
+	}
+	mutex_unlock(&local->iflist_mtx);
+}
+
+int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
+			struct cfg80211_ibss_params *params)
+{
+	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);
+		sdata->u.ibss.fixed_bssid = true;
+	} else
+		sdata->u.ibss.fixed_bssid = false;
+
+	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 = 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);
+	}
+	memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate,
+	       sizeof(params->mcast_rate));
+
+	sdata->vif.bss_conf.beacon_int = params->beacon_interval;
+
+	sdata->u.ibss.chandef = params->chandef;
+	sdata->u.ibss.fixed_channel = params->channel_fixed;
+
+	if (params->ie) {
+		sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len,
+					   GFP_KERNEL);
+		if (sdata->u.ibss.ie)
+			sdata->u.ibss.ie_len = params->ie_len;
+	}
+
+	sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
+	sdata->u.ibss.ibss_join_req = jiffies;
+
+	memcpy(sdata->u.ibss.ssid, params->ssid, params->ssid_len);
+	sdata->u.ibss.ssid_len = params->ssid_len;
+
+	memcpy(&sdata->u.ibss.ht_capa, &params->ht_capa,
+	       sizeof(sdata->u.ibss.ht_capa));
+	memcpy(&sdata->u.ibss.ht_capa_mask, &params->ht_capa_mask,
+	       sizeof(sdata->u.ibss.ht_capa_mask));
+
+	/*
+	 * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is
+	 * reserved, but an HT STA shall protect HT transmissions as though
+	 * the HT Protection field were set to non-HT mixed mode.
+	 *
+	 * In an IBSS, the RIFS Mode field of the HT Operation element is
+	 * also reserved, but an HT STA shall operate as though this field
+	 * were set to 1.
+	 */
+
+	sdata->vif.bss_conf.ht_operation_mode |=
+		  IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED
+		| IEEE80211_HT_PARAM_RIFS_MODE;
+
+	changed |= BSS_CHANGED_HT | BSS_CHANGED_MCAST_RATE;
+	ieee80211_bss_info_change_notify(sdata, changed);
+
+	sdata->smps_mode = IEEE80211_SMPS_OFF;
+	sdata->needed_rx_chains = local->rx_chains;
+	sdata->control_port_over_nl80211 = params->control_port_over_nl80211;
+
+	ieee80211_queue_work(&local->hw, &sdata->work);
+
+	return 0;
+}
+
+int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata)
+{
+	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
+
+	ieee80211_ibss_disconnect(sdata);
+	ifibss->ssid_len = 0;
+	eth_zero_addr(ifibss->bssid);
+
+	/* remove beacon */
+	kfree(sdata->u.ibss.ie);
+	sdata->u.ibss.ie = NULL;
+	sdata->u.ibss.ie_len = 0;
+
+	/* 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));
+
+	synchronize_rcu();
+
+	skb_queue_purge(&sdata->skb_queue);
+
+	del_timer_sync(&sdata->u.ibss.timer);
+
+	return 0;
+}