net/mac80211/ibss.c

   1 /*
   2  * IBSS mode implementation
   3  * Copyright 2003-2008, Jouni Malinen <j@w1.fi>
   4  * Copyright 2004, Instant802 Networks, Inc.
   5  * Copyright 2005, Devicescape Software, Inc.
   6  * Copyright 2006-2007  Jiri Benc <jbenc@suse.cz>
   7  * Copyright 2007, Michael Wu <flamingice@sourmilk.net>
   8  * Copyright 2009, Johannes Berg <johannes@sipsolutions.net>
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License version 2 as
  12  * published by the Free Software Foundation.
  13  */
  14
  15 #include <linux/delay.h>
  16 #include <linux/slab.h>
  17 #include <linux/if_ether.h>
  18 #include <linux/skbuff.h>
  19 #include <linux/if_arp.h>
  20 #include <linux/etherdevice.h>
  21 #include <linux/rtnetlink.h>
  22 #include <net/mac80211.h>
  23
  24 #include "ieee80211_i.h"
  25 #include "driver-ops.h"
  26 #include "rate.h"
  27
  28 #define IEEE80211_SCAN_INTERVAL (2 * HZ)
  29 #define IEEE80211_IBSS_JOIN_TIMEOUT (7 * HZ)
  30
  31 #define IEEE80211_IBSS_MERGE_INTERVAL (30 * HZ)
  32 #define IEEE80211_IBSS_INACTIVITY_LIMIT (60 * HZ)
  33
  34 #define IEEE80211_IBSS_MAX_STA_ENTRIES 128
  35
  36
  37 static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
  38                                       const u8 *bssid, const int beacon_int,
  39                                       struct ieee80211_channel *chan,
  40                                       const u32 basic_rates,
  41                                       const u16 capability, u64 tsf,
  42                                       bool creator)
  43 {
  44         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
  45         struct ieee80211_local *local = sdata->local;
  46         int rates, i;
  47         struct sk_buff *skb;
  48         struct ieee80211_mgmt *mgmt;
  49         u8 *pos;
  50         struct ieee80211_supported_band *sband;
  51         struct cfg80211_bss *bss;
  52         u32 bss_change;
  53         u8 supp_rates[IEEE80211_MAX_SUPP_RATES];
  54         struct cfg80211_chan_def chandef;
  55
  56         lockdep_assert_held(&ifibss->mtx);
  57
  58         /* Reset own TSF to allow time synchronization work. */
  59         drv_reset_tsf(local, sdata);
  60
  61         if (!ether_addr_equal(ifibss->bssid, bssid))
  62                 sta_info_flush(sdata);
  63
  64         /* if merging, indicate to driver that we leave the old IBSS */
  65         if (sdata->vif.bss_conf.ibss_joined) {
  66                 sdata->vif.bss_conf.ibss_joined = false;
  67                 sdata->vif.bss_conf.ibss_creator = false;
  68                 sdata->vif.bss_conf.enable_beacon = false;
  69                 netif_carrier_off(sdata->dev);
  70                 ieee80211_bss_info_change_notify(sdata,
  71                                                  BSS_CHANGED_IBSS |
  72                                                  BSS_CHANGED_BEACON_ENABLED);
  73         }
  74
  75         skb = ifibss->skb;
  76         RCU_INIT_POINTER(ifibss->presp, NULL);
  77         synchronize_rcu();
  78         skb->data = skb->head;
  79         skb->len = 0;
  80         skb_reset_tail_pointer(skb);
  81         skb_reserve(skb, sdata->local->hw.extra_tx_headroom);
  82
  83         sdata->drop_unencrypted = capability & WLAN_CAPABILITY_PRIVACY ? 1 : 0;
  84
  85         cfg80211_chandef_create(&chandef, chan, ifibss->channel_type);
  86         if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef)) {
  87                 chandef.width = NL80211_CHAN_WIDTH_20;
  88                 chandef.center_freq1 = chan->center_freq;
  89         }
  90
  91         ieee80211_vif_release_channel(sdata);
  92         if (ieee80211_vif_use_channel(sdata, &chandef,
  93                                       ifibss->fixed_channel ?
  94                                         IEEE80211_CHANCTX_SHARED :
  95                                         IEEE80211_CHANCTX_EXCLUSIVE)) {
  96                 sdata_info(sdata, "Failed to join IBSS, no channel context\n");
  97                 return;
  98         }
  99
 100         memcpy(ifibss->bssid, bssid, ETH_ALEN);
 101
 102         sband = local->hw.wiphy->bands[chan->band];
 103
 104         /* build supported rates array */
 105         pos = supp_rates;
 106         for (i = 0; i < sband->n_bitrates; i++) {
 107                 int rate = sband->bitrates[i].bitrate;
 108                 u8 basic = 0;
 109                 if (basic_rates & BIT(i))
 110                         basic = 0x80;
 111                 *pos++ = basic | (u8) (rate / 5);
 112         }
 113
 114         /* Build IBSS probe response */
 115         mgmt = (void *) skb_put(skb, 24 + sizeof(mgmt->u.beacon));
 116         memset(mgmt, 0, 24 + sizeof(mgmt->u.beacon));
 117         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 118                                           IEEE80211_STYPE_PROBE_RESP);
 119         eth_broadcast_addr(mgmt->da);
 120         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
 121         memcpy(mgmt->bssid, ifibss->bssid, ETH_ALEN);
 122         mgmt->u.beacon.beacon_int = cpu_to_le16(beacon_int);
 123         mgmt->u.beacon.timestamp = cpu_to_le64(tsf);
 124         mgmt->u.beacon.capab_info = cpu_to_le16(capability);
 125
 126         pos = skb_put(skb, 2 + ifibss->ssid_len);
 127         *pos++ = WLAN_EID_SSID;
 128         *pos++ = ifibss->ssid_len;
 129         memcpy(pos, ifibss->ssid, ifibss->ssid_len);
 130
 131         rates = sband->n_bitrates;
 132         if (rates > 8)
 133                 rates = 8;
 134         pos = skb_put(skb, 2 + rates);
 135         *pos++ = WLAN_EID_SUPP_RATES;
 136         *pos++ = rates;
 137         memcpy(pos, supp_rates, rates);
 138
 139         if (sband->band == IEEE80211_BAND_2GHZ) {
 140                 pos = skb_put(skb, 2 + 1);
 141                 *pos++ = WLAN_EID_DS_PARAMS;
 142                 *pos++ = 1;
 143                 *pos++ = ieee80211_frequency_to_channel(chan->center_freq);
 144         }
 145
 146         pos = skb_put(skb, 2 + 2);
 147         *pos++ = WLAN_EID_IBSS_PARAMS;
 148         *pos++ = 2;
 149         /* FIX: set ATIM window based on scan results */
 150         *pos++ = 0;
 151         *pos++ = 0;
 152
 153         if (sband->n_bitrates > 8) {
 154                 rates = sband->n_bitrates - 8;
 155                 pos = skb_put(skb, 2 + rates);
 156                 *pos++ = WLAN_EID_EXT_SUPP_RATES;
 157                 *pos++ = rates;
 158                 memcpy(pos, &supp_rates[8], rates);
 159         }
 160
 161         if (ifibss->ie_len)
 162                 memcpy(skb_put(skb, ifibss->ie_len),
 163                        ifibss->ie, ifibss->ie_len);
 164
 165         /* add HT capability and information IEs */
 166         if (chandef.width != NL80211_CHAN_WIDTH_20_NOHT &&
 167             sband->ht_cap.ht_supported) {
 168                 pos = skb_put(skb, 4 +
 169                                    sizeof(struct ieee80211_ht_cap) +
 170                                    sizeof(struct ieee80211_ht_operation));
 171                 pos = ieee80211_ie_build_ht_cap(pos, &sband->ht_cap,
 172                                                 sband->ht_cap.cap);
 173                 /*
 174                  * Note: According to 802.11n-2009 9.13.3.1, HT Protection
 175                  * field and RIFS Mode are reserved in IBSS mode, therefore
 176                  * keep them at 0
 177                  */
 178                 pos = ieee80211_ie_build_ht_oper(pos, &sband->ht_cap,
 179                                                  &chandef, 0);
 180         }
 181
 182         if (local->hw.queues >= IEEE80211_NUM_ACS) {
 183                 pos = skb_put(skb, 9);
 184                 *pos++ = WLAN_EID_VENDOR_SPECIFIC;
 185                 *pos++ = 7; /* len */
 186                 *pos++ = 0x00; /* Microsoft OUI 00:50:F2 */
 187                 *pos++ = 0x50;
 188                 *pos++ = 0xf2;
 189                 *pos++ = 2; /* WME */
 190                 *pos++ = 0; /* WME info */
 191                 *pos++ = 1; /* WME ver */
 192                 *pos++ = 0; /* U-APSD no in use */
 193         }
 194
 195         rcu_assign_pointer(ifibss->presp, skb);
 196
 197         sdata->vif.bss_conf.enable_beacon = true;
 198         sdata->vif.bss_conf.beacon_int = beacon_int;
 199         sdata->vif.bss_conf.basic_rates = basic_rates;
 200         bss_change = BSS_CHANGED_BEACON_INT;
 201         bss_change |= ieee80211_reset_erp_info(sdata);
 202         bss_change |= BSS_CHANGED_BSSID;
 203         bss_change |= BSS_CHANGED_BEACON;
 204         bss_change |= BSS_CHANGED_BEACON_ENABLED;
 205         bss_change |= BSS_CHANGED_BASIC_RATES;
 206         bss_change |= BSS_CHANGED_HT;
 207         bss_change |= BSS_CHANGED_IBSS;
 208
 209         /*
 210          * In 5 GHz/802.11a, we can always use short slot time.
 211          * (IEEE 802.11-2012 18.3.8.7)
 212          *
 213          * In 2.4GHz, we must always use long slots in IBSS for compatibility
 214          * reasons.
 215          * (IEEE 802.11-2012 19.4.5)
 216          *
 217          * HT follows these specifications (IEEE 802.11-2012 20.3.18)
 218          */
 219         sdata->vif.bss_conf.use_short_slot = chan->band == IEEE80211_BAND_5GHZ;
 220         bss_change |= BSS_CHANGED_ERP_SLOT;
 221
 222         sdata->vif.bss_conf.ibss_joined = true;
 223         sdata->vif.bss_conf.ibss_creator = creator;
 224         ieee80211_bss_info_change_notify(sdata, bss_change);
 225
 226         ieee80211_sta_def_wmm_params(sdata, sband->n_bitrates, supp_rates);
 227
 228         ifibss->state = IEEE80211_IBSS_MLME_JOINED;
 229         mod_timer(&ifibss->timer,
 230                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
 231
 232         bss = cfg80211_inform_bss_frame(local->hw.wiphy, chan,
 233                                         mgmt, skb->len, 0, GFP_KERNEL);
 234         cfg80211_put_bss(local->hw.wiphy, bss);
 235         netif_carrier_on(sdata->dev);
 236         cfg80211_ibss_joined(sdata->dev, ifibss->bssid, GFP_KERNEL);
 237 }
 238
 239 static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
 240                                     struct ieee80211_bss *bss)
 241 {
 242         struct cfg80211_bss *cbss =
 243                 container_of((void *)bss, struct cfg80211_bss, priv);
 244         struct ieee80211_supported_band *sband;
 245         u32 basic_rates;
 246         int i, j;
 247         u16 beacon_int = cbss->beacon_interval;
 248         const struct cfg80211_bss_ies *ies;
 249         u64 tsf;
 250
 251         lockdep_assert_held(&sdata->u.ibss.mtx);
 252
 253         if (beacon_int < 10)
 254                 beacon_int = 10;
 255
 256         sband = sdata->local->hw.wiphy->bands[cbss->channel->band];
 257
 258         basic_rates = 0;
 259
 260         for (i = 0; i < bss->supp_rates_len; i++) {
 261                 int rate = (bss->supp_rates[i] & 0x7f) * 5;
 262                 bool is_basic = !!(bss->supp_rates[i] & 0x80);
 263
 264                 for (j = 0; j < sband->n_bitrates; j++) {
 265                         if (sband->bitrates[j].bitrate == rate) {
 266                                 if (is_basic)
 267                                         basic_rates |= BIT(j);
 268                                 break;
 269                         }
 270                 }
 271         }
 272
 273         rcu_read_lock();
 274         ies = rcu_dereference(cbss->ies);
 275         tsf = ies->tsf;
 276         rcu_read_unlock();
 277
 278         __ieee80211_sta_join_ibss(sdata, cbss->bssid,
 279                                   beacon_int,
 280                                   cbss->channel,
 281                                   basic_rates,
 282                                   cbss->capability,
 283                                   tsf, false);
 284 }
 285
 286 static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta,
 287                                                   bool auth)
 288         __acquires(RCU)
 289 {
 290         struct ieee80211_sub_if_data *sdata = sta->sdata;
 291         u8 addr[ETH_ALEN];
 292
 293         memcpy(addr, sta->sta.addr, ETH_ALEN);
 294
 295         ibss_dbg(sdata, "Adding new IBSS station %pM\n", addr);
 296
 297         sta_info_pre_move_state(sta, IEEE80211_STA_AUTH);
 298         sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC);
 299         /* authorize the station only if the network is not RSN protected. If
 300          * not wait for the userspace to authorize it */
 301         if (!sta->sdata->u.ibss.control_port)
 302                 sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED);
 303
 304         rate_control_rate_init(sta);
 305
 306         /* If it fails, maybe we raced another insertion? */
 307         if (sta_info_insert_rcu(sta))
 308                 return sta_info_get(sdata, addr);
 309         if (auth && !sdata->u.ibss.auth_frame_registrations) {
 310                 ibss_dbg(sdata,
 311                          "TX Auth SA=%pM DA=%pM BSSID=%pM (auth_transaction=1)\n",
 312                          sdata->vif.addr, addr, sdata->u.ibss.bssid);
 313                 ieee80211_send_auth(sdata, 1, WLAN_AUTH_OPEN, 0, NULL, 0,
 314                                     addr, sdata->u.ibss.bssid, NULL, 0, 0, 0);
 315         }
 316         return sta;
 317 }
 318
 319 static struct sta_info *
 320 ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata,
 321                        const u8 *bssid, const u8 *addr,
 322                        u32 supp_rates, bool auth)
 323         __acquires(RCU)
 324 {
 325         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 326         struct ieee80211_local *local = sdata->local;
 327         struct sta_info *sta;
 328         struct ieee80211_chanctx_conf *chanctx_conf;
 329         int band;
 330
 331         /*
 332          * XXX: Consider removing the least recently used entry and
 333          *      allow new one to be added.
 334          */
 335         if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
 336                 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
 337                                     sdata->name, addr);
 338                 rcu_read_lock();
 339                 return NULL;
 340         }
 341
 342         if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) {
 343                 rcu_read_lock();
 344                 return NULL;
 345         }
 346
 347         if (!ether_addr_equal(bssid, sdata->u.ibss.bssid)) {
 348                 rcu_read_lock();
 349                 return NULL;
 350         }
 351
 352         rcu_read_lock();
 353         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 354         if (WARN_ON_ONCE(!chanctx_conf))
 355                 return NULL;
 356         band = chanctx_conf->def.chan->band;
 357         rcu_read_unlock();
 358
 359         sta = sta_info_alloc(sdata, addr, GFP_KERNEL);
 360         if (!sta) {
 361                 rcu_read_lock();
 362                 return NULL;
 363         }
 364
 365         sta->last_rx = jiffies;
 366
 367         /* make sure mandatory rates are always added */
 368         sta->sta.supp_rates[band] = supp_rates |
 369                         ieee80211_mandatory_rates(local, band);
 370
 371         return ieee80211_ibss_finish_sta(sta, auth);
 372 }
 373
 374 static void ieee80211_rx_mgmt_deauth_ibss(struct ieee80211_sub_if_data *sdata,
 375                                           struct ieee80211_mgmt *mgmt,
 376                                           size_t len)
 377 {
 378         u16 reason = le16_to_cpu(mgmt->u.deauth.reason_code);
 379
 380         if (len < IEEE80211_DEAUTH_FRAME_LEN)
 381                 return;
 382
 383         ibss_dbg(sdata, "RX DeAuth SA=%pM DA=%pM BSSID=%pM (reason: %d)\n",
 384                  mgmt->sa, mgmt->da, mgmt->bssid, reason);
 385         sta_info_destroy_addr(sdata, mgmt->sa);
 386 }
 387
 388 static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata,
 389                                         struct ieee80211_mgmt *mgmt,
 390                                         size_t len)
 391 {
 392         u16 auth_alg, auth_transaction;
 393         struct sta_info *sta;
 394         u8 deauth_frame_buf[IEEE80211_DEAUTH_FRAME_LEN];
 395
 396         lockdep_assert_held(&sdata->u.ibss.mtx);
 397
 398         if (len < 24 + 6)
 399                 return;
 400
 401         auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg);
 402         auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction);
 403
 404         ibss_dbg(sdata,
 405                  "RX Auth SA=%pM DA=%pM BSSID=%pM (auth_transaction=%d)\n",
 406                  mgmt->sa, mgmt->da, mgmt->bssid, auth_transaction);
 407
 408         if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1)
 409                 return;
 410
 411         sta_info_destroy_addr(sdata, mgmt->sa);
 412         sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa, 0, false);
 413         rcu_read_unlock();
 414
 415         /*
 416          * if we have any problem in allocating the new station, we reply with a
 417          * DEAUTH frame to tell the other end that we had a problem
 418          */
 419         if (!sta) {
 420                 ieee80211_send_deauth_disassoc(sdata, sdata->u.ibss.bssid,
 421                                                IEEE80211_STYPE_DEAUTH,
 422                                                WLAN_REASON_UNSPECIFIED, true,
 423                                                deauth_frame_buf);
 424                 return;
 425         }
 426
 427         /*
 428          * IEEE 802.11 standard does not require authentication in IBSS
 429          * networks and most implementations do not seem to use it.
 430          * However, try to reply to authentication attempts if someone
 431          * has actually implemented this.
 432          */
 433         ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, 0, NULL, 0,
 434                             mgmt->sa, sdata->u.ibss.bssid, NULL, 0, 0, 0);
 435 }
 436
 437 static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
 438                                   struct ieee80211_mgmt *mgmt, size_t len,
 439                                   struct ieee80211_rx_status *rx_status,
 440                                   struct ieee802_11_elems *elems)
 441 {
 442         struct ieee80211_local *local = sdata->local;
 443         int freq;
 444         struct cfg80211_bss *cbss;
 445         struct ieee80211_bss *bss;
 446         struct sta_info *sta;
 447         struct ieee80211_channel *channel;
 448         u64 beacon_timestamp, rx_timestamp;
 449         u32 supp_rates = 0;
 450         enum ieee80211_band band = rx_status->band;
 451         struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band];
 452         bool rates_updated = false;
 453
 454         if (elems->ds_params && elems->ds_params_len == 1)
 455                 freq = ieee80211_channel_to_frequency(elems->ds_params[0],
 456                                                       band);
 457         else
 458                 freq = rx_status->freq;
 459
 460         channel = ieee80211_get_channel(local->hw.wiphy, freq);
 461
 462         if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
 463                 return;
 464
 465         if (sdata->vif.type == NL80211_IFTYPE_ADHOC &&
 466             ether_addr_equal(mgmt->bssid, sdata->u.ibss.bssid)) {
 467
 468                 rcu_read_lock();
 469                 sta = sta_info_get(sdata, mgmt->sa);
 470
 471                 if (elems->supp_rates) {
 472                         supp_rates = ieee80211_sta_get_rates(local, elems,
 473                                                              band, NULL);
 474                         if (sta) {
 475                                 u32 prev_rates;
 476
 477                                 prev_rates = sta->sta.supp_rates[band];
 478                                 /* make sure mandatory rates are always added */
 479                                 sta->sta.supp_rates[band] = supp_rates |
 480                                         ieee80211_mandatory_rates(local, band);
 481
 482                                 if (sta->sta.supp_rates[band] != prev_rates) {
 483                                         ibss_dbg(sdata,
 484                                                  "updated supp_rates set for %pM based on beacon/probe_resp (0x%x -> 0x%x)\n",
 485                                                  sta->sta.addr, prev_rates,
 486                                                  sta->sta.supp_rates[band]);
 487                                         rates_updated = true;
 488                                 }
 489                         } else {
 490                                 rcu_read_unlock();
 491                                 sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid,
 492                                                 mgmt->sa, supp_rates, true);
 493                         }
 494                 }
 495
 496                 if (sta && elems->wmm_info)
 497                         set_sta_flag(sta, WLAN_STA_WME);
 498
 499                 if (sta && elems->ht_operation && elems->ht_cap_elem &&
 500                     sdata->u.ibss.channel_type != NL80211_CHAN_NO_HT) {
 501                         /* we both use HT */
 502                         struct ieee80211_ht_cap htcap_ie;
 503                         struct cfg80211_chan_def chandef;
 504
 505                         ieee80211_ht_oper_to_chandef(channel,
 506                                                      elems->ht_operation,
 507                                                      &chandef);
 508
 509                         memcpy(&htcap_ie, elems->ht_cap_elem, sizeof(htcap_ie));
 510
 511                         /*
 512                          * fall back to HT20 if we don't use or use
 513                          * the other extension channel
 514                          */
 515                         if (cfg80211_get_chandef_type(&chandef) !=
 516                                                 sdata->u.ibss.channel_type)
 517                                 htcap_ie.cap_info &=
 518                                         cpu_to_le16(~IEEE80211_HT_CAP_SUP_WIDTH_20_40);
 519
 520                         rates_updated |= ieee80211_ht_cap_ie_to_sta_ht_cap(
 521                                                 sdata, sband, &htcap_ie, sta);
 522                 }
 523
 524                 if (sta && rates_updated) {
 525                         drv_sta_rc_update(local, sdata, &sta->sta,
 526                                           IEEE80211_RC_SUPP_RATES_CHANGED);
 527                         rate_control_rate_init(sta);
 528                 }
 529
 530                 rcu_read_unlock();
 531         }
 532
 533         bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems,
 534                                         channel);
 535         if (!bss)
 536                 return;
 537
 538         cbss = container_of((void *)bss, struct cfg80211_bss, priv);
 539
 540         /* same for beacon and probe response */
 541         beacon_timestamp = le64_to_cpu(mgmt->u.beacon.timestamp);
 542
 543         /* check if we need to merge IBSS */
 544
 545         /* we use a fixed BSSID */
 546         if (sdata->u.ibss.fixed_bssid)
 547                 goto put_bss;
 548
 549         /* not an IBSS */
 550         if (!(cbss->capability & WLAN_CAPABILITY_IBSS))
 551                 goto put_bss;
 552
 553         /* different channel */
 554         if (sdata->u.ibss.fixed_channel &&
 555             sdata->u.ibss.channel != cbss->channel)
 556                 goto put_bss;
 557
 558         /* different SSID */
 559         if (elems->ssid_len != sdata->u.ibss.ssid_len ||
 560             memcmp(elems->ssid, sdata->u.ibss.ssid,
 561                                 sdata->u.ibss.ssid_len))
 562                 goto put_bss;
 563
 564         /* same BSSID */
 565         if (ether_addr_equal(cbss->bssid, sdata->u.ibss.bssid))
 566                 goto put_bss;
 567
 568         if (ieee80211_have_rx_timestamp(rx_status)) {
 569                 /* time when timestamp field was received */
 570                 rx_timestamp =
 571                         ieee80211_calculate_rx_timestamp(local, rx_status,
 572                                                          len + FCS_LEN, 24);
 573         } else {
 574                 /*
 575                  * second best option: get current TSF
 576                  * (will return -1 if not supported)
 577                  */
 578                 rx_timestamp = drv_get_tsf(local, sdata);
 579         }
 580
 581         ibss_dbg(sdata,
 582                  "RX beacon SA=%pM BSSID=%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n",
 583                  mgmt->sa, mgmt->bssid,
 584                  (unsigned long long)rx_timestamp,
 585                  (unsigned long long)beacon_timestamp,
 586                  (unsigned long long)(rx_timestamp - beacon_timestamp),
 587                  jiffies);
 588
 589         if (beacon_timestamp > rx_timestamp) {
 590                 ibss_dbg(sdata,
 591                          "beacon TSF higher than local TSF - IBSS merge with BSSID %pM\n",
 592                          mgmt->bssid);
 593                 ieee80211_sta_join_ibss(sdata, bss);
 594                 supp_rates = ieee80211_sta_get_rates(local, elems, band, NULL);
 595                 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
 596                                        supp_rates, true);
 597                 rcu_read_unlock();
 598         }
 599
 600  put_bss:
 601         ieee80211_rx_bss_put(local, bss);
 602 }
 603
 604 void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata,
 605                               const u8 *bssid, const u8 *addr,
 606                               u32 supp_rates)
 607 {
 608         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 609         struct ieee80211_local *local = sdata->local;
 610         struct sta_info *sta;
 611         struct ieee80211_chanctx_conf *chanctx_conf;
 612         int band;
 613
 614         /*
 615          * XXX: Consider removing the least recently used entry and
 616          *      allow new one to be added.
 617          */
 618         if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
 619                 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
 620                                     sdata->name, addr);
 621                 return;
 622         }
 623
 624         if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH)
 625                 return;
 626
 627         if (!ether_addr_equal(bssid, sdata->u.ibss.bssid))
 628                 return;
 629
 630         rcu_read_lock();
 631         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
 632         if (WARN_ON_ONCE(!chanctx_conf)) {
 633                 rcu_read_unlock();
 634                 return;
 635         }
 636         band = chanctx_conf->def.chan->band;
 637         rcu_read_unlock();
 638
 639         sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
 640         if (!sta)
 641                 return;
 642
 643         sta->last_rx = jiffies;
 644
 645         /* make sure mandatory rates are always added */
 646         sta->sta.supp_rates[band] = supp_rates |
 647                         ieee80211_mandatory_rates(local, band);
 648
 649         spin_lock(&ifibss->incomplete_lock);
 650         list_add(&sta->list, &ifibss->incomplete_stations);
 651         spin_unlock(&ifibss->incomplete_lock);
 652         ieee80211_queue_work(&local->hw, &sdata->work);
 653 }
 654
 655 static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata)
 656 {
 657         struct ieee80211_local *local = sdata->local;
 658         int active = 0;
 659         struct sta_info *sta;
 660
 661         lockdep_assert_held(&sdata->u.ibss.mtx);
 662
 663         rcu_read_lock();
 664
 665         list_for_each_entry_rcu(sta, &local->sta_list, list) {
 666                 if (sta->sdata == sdata &&
 667                     time_after(sta->last_rx + IEEE80211_IBSS_MERGE_INTERVAL,
 668                                jiffies)) {
 669                         active++;
 670                         break;
 671                 }
 672         }
 673
 674         rcu_read_unlock();
 675
 676         return active;
 677 }
 678
 679 /*
 680  * This function is called with state == IEEE80211_IBSS_MLME_JOINED
 681  */
 682
 683 static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata)
 684 {
 685         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 686
 687         lockdep_assert_held(&ifibss->mtx);
 688
 689         mod_timer(&ifibss->timer,
 690                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
 691
 692         ieee80211_sta_expire(sdata, IEEE80211_IBSS_INACTIVITY_LIMIT);
 693
 694         if (time_before(jiffies, ifibss->last_scan_completed +
 695                        IEEE80211_IBSS_MERGE_INTERVAL))
 696                 return;
 697
 698         if (ieee80211_sta_active_ibss(sdata))
 699                 return;
 700
 701         if (ifibss->fixed_channel)
 702                 return;
 703
 704         sdata_info(sdata,
 705                    "No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge)\n");
 706
 707         ieee80211_request_ibss_scan(sdata, ifibss->ssid, ifibss->ssid_len,
 708                                     NULL);
 709 }
 710
 711 static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata)
 712 {
 713         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 714         u8 bssid[ETH_ALEN];
 715         u16 capability;
 716         int i;
 717
 718         lockdep_assert_held(&ifibss->mtx);
 719
 720         if (ifibss->fixed_bssid) {
 721                 memcpy(bssid, ifibss->bssid, ETH_ALEN);
 722         } else {
 723                 /* Generate random, not broadcast, locally administered BSSID. Mix in
 724                  * own MAC address to make sure that devices that do not have proper
 725                  * random number generator get different BSSID. */
 726                 get_random_bytes(bssid, ETH_ALEN);
 727                 for (i = 0; i < ETH_ALEN; i++)
 728                         bssid[i] ^= sdata->vif.addr[i];
 729                 bssid[0] &= ~0x01;
 730                 bssid[0] |= 0x02;
 731         }
 732
 733         sdata_info(sdata, "Creating new IBSS network, BSSID %pM\n", bssid);
 734
 735         capability = WLAN_CAPABILITY_IBSS;
 736
 737         if (ifibss->privacy)
 738                 capability |= WLAN_CAPABILITY_PRIVACY;
 739         else
 740                 sdata->drop_unencrypted = 0;
 741
 742         __ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int,
 743                                   ifibss->channel, ifibss->basic_rates,
 744                                   capability, 0, true);
 745 }
 746
 747 /*
 748  * This function is called with state == IEEE80211_IBSS_MLME_SEARCH
 749  */
 750
 751 static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata)
 752 {
 753         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 754         struct ieee80211_local *local = sdata->local;
 755         struct cfg80211_bss *cbss;
 756         struct ieee80211_channel *chan = NULL;
 757         const u8 *bssid = NULL;
 758         int active_ibss;
 759         u16 capability;
 760
 761         lockdep_assert_held(&ifibss->mtx);
 762
 763         active_ibss = ieee80211_sta_active_ibss(sdata);
 764         ibss_dbg(sdata, "sta_find_ibss (active_ibss=%d)\n", active_ibss);
 765
 766         if (active_ibss)
 767                 return;
 768
 769         capability = WLAN_CAPABILITY_IBSS;
 770         if (ifibss->privacy)
 771                 capability |= WLAN_CAPABILITY_PRIVACY;
 772         if (ifibss->fixed_bssid)
 773                 bssid = ifibss->bssid;
 774         if (ifibss->fixed_channel)
 775                 chan = ifibss->channel;
 776         if (!is_zero_ether_addr(ifibss->bssid))
 777                 bssid = ifibss->bssid;
 778         cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid,
 779                                 ifibss->ssid, ifibss->ssid_len,
 780                                 WLAN_CAPABILITY_IBSS | WLAN_CAPABILITY_PRIVACY,
 781                                 capability);
 782
 783         if (cbss) {
 784                 struct ieee80211_bss *bss;
 785
 786                 bss = (void *)cbss->priv;
 787                 ibss_dbg(sdata,
 788                          "sta_find_ibss: selected %pM current %pM\n",
 789                          cbss->bssid, ifibss->bssid);
 790                 sdata_info(sdata,
 791                            "Selected IBSS BSSID %pM based on configured SSID\n",
 792                            cbss->bssid);
 793
 794                 ieee80211_sta_join_ibss(sdata, bss);
 795                 ieee80211_rx_bss_put(local, bss);
 796                 return;
 797         }
 798
 799         ibss_dbg(sdata, "sta_find_ibss: did not try to join ibss\n");
 800
 801         /* Selected IBSS not found in current scan results - try to scan */
 802         if (time_after(jiffies, ifibss->last_scan_completed +
 803                                         IEEE80211_SCAN_INTERVAL)) {
 804                 sdata_info(sdata, "Trigger new scan to find an IBSS to join\n");
 805
 806                 ieee80211_request_ibss_scan(sdata, ifibss->ssid,
 807                                             ifibss->ssid_len, chan);
 808         } else {
 809                 int interval = IEEE80211_SCAN_INTERVAL;
 810
 811                 if (time_after(jiffies, ifibss->ibss_join_req +
 812                                IEEE80211_IBSS_JOIN_TIMEOUT))
 813                         ieee80211_sta_create_ibss(sdata);
 814
 815                 mod_timer(&ifibss->timer,
 816                           round_jiffies(jiffies + interval));
 817         }
 818 }
 819
 820 static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata,
 821                                         struct sk_buff *req)
 822 {
 823         struct ieee80211_mgmt *mgmt = (void *)req->data;
 824         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 825         struct ieee80211_local *local = sdata->local;
 826         int tx_last_beacon, len = req->len;
 827         struct sk_buff *skb;
 828         struct ieee80211_mgmt *resp;
 829         struct sk_buff *presp;
 830         u8 *pos, *end;
 831
 832         lockdep_assert_held(&ifibss->mtx);
 833
 834         presp = rcu_dereference_protected(ifibss->presp,
 835                                           lockdep_is_held(&ifibss->mtx));
 836
 837         if (ifibss->state != IEEE80211_IBSS_MLME_JOINED ||
 838             len < 24 + 2 || !presp)
 839                 return;
 840
 841         tx_last_beacon = drv_tx_last_beacon(local);
 842
 843         ibss_dbg(sdata,
 844                  "RX ProbeReq SA=%pM DA=%pM BSSID=%pM (tx_last_beacon=%d)\n",
 845                  mgmt->sa, mgmt->da, mgmt->bssid, tx_last_beacon);
 846
 847         if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da))
 848                 return;
 849
 850         if (!ether_addr_equal(mgmt->bssid, ifibss->bssid) &&
 851             !is_broadcast_ether_addr(mgmt->bssid))
 852                 return;
 853
 854         end = ((u8 *) mgmt) + len;
 855         pos = mgmt->u.probe_req.variable;
 856         if (pos[0] != WLAN_EID_SSID ||
 857             pos + 2 + pos[1] > end) {
 858                 ibss_dbg(sdata, "Invalid SSID IE in ProbeReq from %pM\n",
 859                          mgmt->sa);
 860                 return;
 861         }
 862         if (pos[1] != 0 &&
 863             (pos[1] != ifibss->ssid_len ||
 864              memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) {
 865                 /* Ignore ProbeReq for foreign SSID */
 866                 return;
 867         }
 868
 869         /* Reply with ProbeResp */
 870         skb = skb_copy(presp, GFP_KERNEL);
 871         if (!skb)
 872                 return;
 873
 874         resp = (struct ieee80211_mgmt *) skb->data;
 875         memcpy(resp->da, mgmt->sa, ETH_ALEN);
 876         ibss_dbg(sdata, "Sending ProbeResp to %pM\n", resp->da);
 877         IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
 878         ieee80211_tx_skb(sdata, skb);
 879 }
 880
 881 static
 882 void ieee80211_rx_mgmt_probe_beacon(struct ieee80211_sub_if_data *sdata,
 883                                     struct ieee80211_mgmt *mgmt, size_t len,
 884                                     struct ieee80211_rx_status *rx_status)
 885 {
 886         size_t baselen;
 887         struct ieee802_11_elems elems;
 888
 889         BUILD_BUG_ON(offsetof(typeof(mgmt->u.probe_resp), variable) !=
 890                      offsetof(typeof(mgmt->u.beacon), variable));
 891
 892         /*
 893          * either beacon or probe_resp but the variable field is at the
 894          * same offset
 895          */
 896         baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
 897         if (baselen > len)
 898                 return;
 899
 900         ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
 901                                 &elems);
 902
 903         ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems);
 904 }
 905
 906 void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
 907                                    struct sk_buff *skb)
 908 {
 909         struct ieee80211_rx_status *rx_status;
 910         struct ieee80211_mgmt *mgmt;
 911         u16 fc;
 912
 913         rx_status = IEEE80211_SKB_RXCB(skb);
 914         mgmt = (struct ieee80211_mgmt *) skb->data;
 915         fc = le16_to_cpu(mgmt->frame_control);
 916
 917         mutex_lock(&sdata->u.ibss.mtx);
 918
 919         if (!sdata->u.ibss.ssid_len)
 920                 goto mgmt_out; /* not ready to merge yet */
 921
 922         switch (fc & IEEE80211_FCTL_STYPE) {
 923         case IEEE80211_STYPE_PROBE_REQ:
 924                 ieee80211_rx_mgmt_probe_req(sdata, skb);
 925                 break;
 926         case IEEE80211_STYPE_PROBE_RESP:
 927         case IEEE80211_STYPE_BEACON:
 928                 ieee80211_rx_mgmt_probe_beacon(sdata, mgmt, skb->len,
 929                                                rx_status);
 930                 break;
 931         case IEEE80211_STYPE_AUTH:
 932                 ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len);
 933                 break;
 934         case IEEE80211_STYPE_DEAUTH:
 935                 ieee80211_rx_mgmt_deauth_ibss(sdata, mgmt, skb->len);
 936                 break;
 937         }
 938
 939  mgmt_out:
 940         mutex_unlock(&sdata->u.ibss.mtx);
 941 }
 942
 943 void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata)
 944 {
 945         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 946         struct sta_info *sta;
 947
 948         mutex_lock(&ifibss->mtx);
 949
 950         /*
 951          * Work could be scheduled after scan or similar
 952          * when we aren't even joined (or trying) with a
 953          * network.
 954          */
 955         if (!ifibss->ssid_len)
 956                 goto out;
 957
 958         spin_lock_bh(&ifibss->incomplete_lock);
 959         while (!list_empty(&ifibss->incomplete_stations)) {
 960                 sta = list_first_entry(&ifibss->incomplete_stations,
 961                                        struct sta_info, list);
 962                 list_del(&sta->list);
 963                 spin_unlock_bh(&ifibss->incomplete_lock);
 964
 965                 ieee80211_ibss_finish_sta(sta, true);
 966                 rcu_read_unlock();
 967                 spin_lock_bh(&ifibss->incomplete_lock);
 968         }
 969         spin_unlock_bh(&ifibss->incomplete_lock);
 970
 971         switch (ifibss->state) {
 972         case IEEE80211_IBSS_MLME_SEARCH:
 973                 ieee80211_sta_find_ibss(sdata);
 974                 break;
 975         case IEEE80211_IBSS_MLME_JOINED:
 976                 ieee80211_sta_merge_ibss(sdata);
 977                 break;
 978         default:
 979                 WARN_ON(1);
 980                 break;
 981         }
 982
 983  out:
 984         mutex_unlock(&ifibss->mtx);
 985 }
 986
 987 static void ieee80211_ibss_timer(unsigned long data)
 988 {
 989         struct ieee80211_sub_if_data *sdata =
 990                 (struct ieee80211_sub_if_data *) data;
 991
 992         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
 993 }
 994
 995 void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata)
 996 {
 997         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 998
 999         setup_timer(&ifibss->timer, ieee80211_ibss_timer,
1000                     (unsigned long) sdata);
1001         mutex_init(&ifibss->mtx);
1002         INIT_LIST_HEAD(&ifibss->incomplete_stations);
1003         spin_lock_init(&ifibss->incomplete_lock);
1004 }
1005
1006 /* scan finished notification */
1007 void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local)
1008 {
1009         struct ieee80211_sub_if_data *sdata;
1010
1011         mutex_lock(&local->iflist_mtx);
1012         list_for_each_entry(sdata, &local->interfaces, list) {
1013                 if (!ieee80211_sdata_running(sdata))
1014                         continue;
1015                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1016                         continue;
1017                 sdata->u.ibss.last_scan_completed = jiffies;
1018                 ieee80211_queue_work(&local->hw, &sdata->work);
1019         }
1020         mutex_unlock(&local->iflist_mtx);
1021 }
1022
1023 int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
1024                         struct cfg80211_ibss_params *params)
1025 {
1026         struct sk_buff *skb;
1027         u32 changed = 0;
1028
1029         skb = dev_alloc_skb(sdata->local->hw.extra_tx_headroom +
1030                             sizeof(struct ieee80211_hdr_3addr) +
1031                             12 /* struct ieee80211_mgmt.u.beacon */ +
1032                             2 + IEEE80211_MAX_SSID_LEN /* max SSID */ +
1033                             2 + 8 /* max Supported Rates */ +
1034                             3 /* max DS params */ +
1035                             4 /* IBSS params */ +
1036                             2 + (IEEE80211_MAX_SUPP_RATES - 8) +
1037                             2 + sizeof(struct ieee80211_ht_cap) +
1038                             2 + sizeof(struct ieee80211_ht_operation) +
1039                             params->ie_len);
1040         if (!skb)
1041                 return -ENOMEM;
1042
1043         mutex_lock(&sdata->u.ibss.mtx);
1044
1045         if (params->bssid) {
1046                 memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN);
1047                 sdata->u.ibss.fixed_bssid = true;
1048         } else
1049                 sdata->u.ibss.fixed_bssid = false;
1050
1051         sdata->u.ibss.privacy = params->privacy;
1052         sdata->u.ibss.control_port = params->control_port;
1053         sdata->u.ibss.basic_rates = params->basic_rates;
1054         memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate,
1055                sizeof(params->mcast_rate));
1056
1057         sdata->vif.bss_conf.beacon_int = params->beacon_interval;
1058
1059         sdata->u.ibss.channel = params->chandef.chan;
1060         sdata->u.ibss.channel_type =
1061                 cfg80211_get_chandef_type(&params->chandef);
1062         sdata->u.ibss.fixed_channel = params->channel_fixed;
1063
1064         if (params->ie) {
1065                 sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len,
1066                                            GFP_KERNEL);
1067                 if (sdata->u.ibss.ie)
1068                         sdata->u.ibss.ie_len = params->ie_len;
1069         }
1070
1071         sdata->u.ibss.skb = skb;
1072         sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
1073         sdata->u.ibss.ibss_join_req = jiffies;
1074
1075         memcpy(sdata->u.ibss.ssid, params->ssid, params->ssid_len);
1076         sdata->u.ibss.ssid_len = params->ssid_len;
1077
1078         mutex_unlock(&sdata->u.ibss.mtx);
1079
1080         /*
1081          * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is
1082          * reserved, but an HT STA shall protect HT transmissions as though
1083          * the HT Protection field were set to non-HT mixed mode.
1084          *
1085          * In an IBSS, the RIFS Mode field of the HT Operation element is
1086          * also reserved, but an HT STA shall operate as though this field
1087          * were set to 1.
1088          */
1089
1090         sdata->vif.bss_conf.ht_operation_mode |=
1091                   IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED
1092                 | IEEE80211_HT_PARAM_RIFS_MODE;
1093
1094         changed |= BSS_CHANGED_HT;
1095         ieee80211_bss_info_change_notify(sdata, changed);
1096
1097         sdata->smps_mode = IEEE80211_SMPS_OFF;
1098         sdata->needed_rx_chains = sdata->local->rx_chains;
1099
1100         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1101
1102         return 0;
1103 }
1104
1105 int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata)
1106 {
1107         struct sk_buff *skb;
1108         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1109         struct ieee80211_local *local = sdata->local;
1110         struct cfg80211_bss *cbss;
1111         u16 capability;
1112         int active_ibss;
1113         struct sta_info *sta;
1114
1115         mutex_lock(&sdata->u.ibss.mtx);
1116
1117         active_ibss = ieee80211_sta_active_ibss(sdata);
1118
1119         if (!active_ibss && !is_zero_ether_addr(ifibss->bssid)) {
1120                 capability = WLAN_CAPABILITY_IBSS;
1121
1122                 if (ifibss->privacy)
1123                         capability |= WLAN_CAPABILITY_PRIVACY;
1124
1125                 cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->channel,
1126                                         ifibss->bssid, ifibss->ssid,
1127                                         ifibss->ssid_len, WLAN_CAPABILITY_IBSS |
1128                                         WLAN_CAPABILITY_PRIVACY,
1129                                         capability);
1130
1131                 if (cbss) {
1132                         cfg80211_unlink_bss(local->hw.wiphy, cbss);
1133                         cfg80211_put_bss(local->hw.wiphy, cbss);
1134                 }
1135         }
1136
1137         ifibss->state = IEEE80211_IBSS_MLME_SEARCH;
1138         memset(ifibss->bssid, 0, ETH_ALEN);
1139         ifibss->ssid_len = 0;
1140
1141         sta_info_flush(sdata);
1142
1143         spin_lock_bh(&ifibss->incomplete_lock);
1144         while (!list_empty(&ifibss->incomplete_stations)) {
1145                 sta = list_first_entry(&ifibss->incomplete_stations,
1146                                        struct sta_info, list);
1147                 list_del(&sta->list);
1148                 spin_unlock_bh(&ifibss->incomplete_lock);
1149
1150                 sta_info_free(local, sta);
1151                 spin_lock_bh(&ifibss->incomplete_lock);
1152         }
1153         spin_unlock_bh(&ifibss->incomplete_lock);
1154
1155         netif_carrier_off(sdata->dev);
1156
1157         /* remove beacon */
1158         kfree(sdata->u.ibss.ie);
1159         skb = rcu_dereference_protected(sdata->u.ibss.presp,
1160                                         lockdep_is_held(&sdata->u.ibss.mtx));
1161         RCU_INIT_POINTER(sdata->u.ibss.presp, NULL);
1162         sdata->vif.bss_conf.ibss_joined = false;
1163         sdata->vif.bss_conf.ibss_creator = false;
1164         sdata->vif.bss_conf.enable_beacon = false;
1165         clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state);
1166         ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED |
1167                                                 BSS_CHANGED_IBSS);
1168         synchronize_rcu();
1169         kfree_skb(skb);
1170
1171         skb_queue_purge(&sdata->skb_queue);
1172
1173         del_timer_sync(&sdata->u.ibss.timer);
1174
1175         mutex_unlock(&sdata->u.ibss.mtx);
1176
1177         return 0;
1178 }