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mac80211: fix ibss scanning
[~shefty/rdma-dev.git] / 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         skb = ifibss->skb;
62         RCU_INIT_POINTER(ifibss->presp, NULL);
63         synchronize_rcu();
64         skb->data = skb->head;
65         skb->len = 0;
66         skb_reset_tail_pointer(skb);
67         skb_reserve(skb, sdata->local->hw.extra_tx_headroom);
68
69         if (!ether_addr_equal(ifibss->bssid, bssid))
70                 sta_info_flush(sdata->local, sdata);
71
72         /* if merging, indicate to driver that we leave the old IBSS */
73         if (sdata->vif.bss_conf.ibss_joined) {
74                 sdata->vif.bss_conf.ibss_joined = false;
75                 sdata->vif.bss_conf.ibss_creator = false;
76                 netif_carrier_off(sdata->dev);
77                 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_IBSS);
78         }
79
80         sdata->drop_unencrypted = capability & WLAN_CAPABILITY_PRIVACY ? 1 : 0;
81
82         cfg80211_chandef_create(&chandef, chan, ifibss->channel_type);
83         if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef)) {
84                 chandef.width = NL80211_CHAN_WIDTH_20;
85                 chandef.center_freq1 = chan->center_freq;
86         }
87
88         ieee80211_vif_release_channel(sdata);
89         if (ieee80211_vif_use_channel(sdata, &chandef,
90                                       ifibss->fixed_channel ?
91                                         IEEE80211_CHANCTX_SHARED :
92                                         IEEE80211_CHANCTX_EXCLUSIVE)) {
93                 sdata_info(sdata, "Failed to join IBSS, no channel context\n");
94                 return;
95         }
96
97         memcpy(ifibss->bssid, bssid, ETH_ALEN);
98
99         sband = local->hw.wiphy->bands[chan->band];
100
101         /* build supported rates array */
102         pos = supp_rates;
103         for (i = 0; i < sband->n_bitrates; i++) {
104                 int rate = sband->bitrates[i].bitrate;
105                 u8 basic = 0;
106                 if (basic_rates & BIT(i))
107                         basic = 0x80;
108                 *pos++ = basic | (u8) (rate / 5);
109         }
110
111         /* Build IBSS probe response */
112         mgmt = (void *) skb_put(skb, 24 + sizeof(mgmt->u.beacon));
113         memset(mgmt, 0, 24 + sizeof(mgmt->u.beacon));
114         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
115                                           IEEE80211_STYPE_PROBE_RESP);
116         eth_broadcast_addr(mgmt->da);
117         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
118         memcpy(mgmt->bssid, ifibss->bssid, ETH_ALEN);
119         mgmt->u.beacon.beacon_int = cpu_to_le16(beacon_int);
120         mgmt->u.beacon.timestamp = cpu_to_le64(tsf);
121         mgmt->u.beacon.capab_info = cpu_to_le16(capability);
122
123         pos = skb_put(skb, 2 + ifibss->ssid_len);
124         *pos++ = WLAN_EID_SSID;
125         *pos++ = ifibss->ssid_len;
126         memcpy(pos, ifibss->ssid, ifibss->ssid_len);
127
128         rates = sband->n_bitrates;
129         if (rates > 8)
130                 rates = 8;
131         pos = skb_put(skb, 2 + rates);
132         *pos++ = WLAN_EID_SUPP_RATES;
133         *pos++ = rates;
134         memcpy(pos, supp_rates, rates);
135
136         if (sband->band == IEEE80211_BAND_2GHZ) {
137                 pos = skb_put(skb, 2 + 1);
138                 *pos++ = WLAN_EID_DS_PARAMS;
139                 *pos++ = 1;
140                 *pos++ = ieee80211_frequency_to_channel(chan->center_freq);
141         }
142
143         pos = skb_put(skb, 2 + 2);
144         *pos++ = WLAN_EID_IBSS_PARAMS;
145         *pos++ = 2;
146         /* FIX: set ATIM window based on scan results */
147         *pos++ = 0;
148         *pos++ = 0;
149
150         if (sband->n_bitrates > 8) {
151                 rates = sband->n_bitrates - 8;
152                 pos = skb_put(skb, 2 + rates);
153                 *pos++ = WLAN_EID_EXT_SUPP_RATES;
154                 *pos++ = rates;
155                 memcpy(pos, &supp_rates[8], rates);
156         }
157
158         if (ifibss->ie_len)
159                 memcpy(skb_put(skb, ifibss->ie_len),
160                        ifibss->ie, ifibss->ie_len);
161
162         /* add HT capability and information IEs */
163         if (chandef.width != NL80211_CHAN_WIDTH_20_NOHT &&
164             sband->ht_cap.ht_supported) {
165                 pos = skb_put(skb, 4 +
166                                    sizeof(struct ieee80211_ht_cap) +
167                                    sizeof(struct ieee80211_ht_operation));
168                 pos = ieee80211_ie_build_ht_cap(pos, &sband->ht_cap,
169                                                 sband->ht_cap.cap);
170                 /*
171                  * Note: According to 802.11n-2009 9.13.3.1, HT Protection
172                  * field and RIFS Mode are reserved in IBSS mode, therefore
173                  * keep them at 0
174                  */
175                 pos = ieee80211_ie_build_ht_oper(pos, &sband->ht_cap,
176                                                  &chandef, 0);
177         }
178
179         if (local->hw.queues >= IEEE80211_NUM_ACS) {
180                 pos = skb_put(skb, 9);
181                 *pos++ = WLAN_EID_VENDOR_SPECIFIC;
182                 *pos++ = 7; /* len */
183                 *pos++ = 0x00; /* Microsoft OUI 00:50:F2 */
184                 *pos++ = 0x50;
185                 *pos++ = 0xf2;
186                 *pos++ = 2; /* WME */
187                 *pos++ = 0; /* WME info */
188                 *pos++ = 1; /* WME ver */
189                 *pos++ = 0; /* U-APSD no in use */
190         }
191
192         rcu_assign_pointer(ifibss->presp, skb);
193
194         sdata->vif.bss_conf.beacon_int = beacon_int;
195         sdata->vif.bss_conf.basic_rates = basic_rates;
196         bss_change = BSS_CHANGED_BEACON_INT;
197         bss_change |= ieee80211_reset_erp_info(sdata);
198         bss_change |= BSS_CHANGED_BSSID;
199         bss_change |= BSS_CHANGED_BEACON;
200         bss_change |= BSS_CHANGED_BEACON_ENABLED;
201         bss_change |= BSS_CHANGED_BASIC_RATES;
202         bss_change |= BSS_CHANGED_HT;
203         bss_change |= BSS_CHANGED_IBSS;
204
205         /*
206          * In 5 GHz/802.11a, we can always use short slot time.
207          * (IEEE 802.11-2012 18.3.8.7)
208          *
209          * In 2.4GHz, we must always use long slots in IBSS for compatibility
210          * reasons.
211          * (IEEE 802.11-2012 19.4.5)
212          *
213          * HT follows these specifications (IEEE 802.11-2012 20.3.18)
214          */
215         sdata->vif.bss_conf.use_short_slot = chan->band == IEEE80211_BAND_5GHZ;
216         bss_change |= BSS_CHANGED_ERP_SLOT;
217
218         sdata->vif.bss_conf.ibss_joined = true;
219         sdata->vif.bss_conf.ibss_creator = creator;
220         ieee80211_bss_info_change_notify(sdata, bss_change);
221
222         ieee80211_sta_def_wmm_params(sdata, sband->n_bitrates, supp_rates);
223
224         ifibss->state = IEEE80211_IBSS_MLME_JOINED;
225         mod_timer(&ifibss->timer,
226                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
227
228         bss = cfg80211_inform_bss_frame(local->hw.wiphy, chan,
229                                         mgmt, skb->len, 0, GFP_KERNEL);
230         cfg80211_put_bss(bss);
231         netif_carrier_on(sdata->dev);
232         cfg80211_ibss_joined(sdata->dev, ifibss->bssid, GFP_KERNEL);
233 }
234
235 static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
236                                     struct ieee80211_bss *bss)
237 {
238         struct cfg80211_bss *cbss =
239                 container_of((void *)bss, struct cfg80211_bss, priv);
240         struct ieee80211_supported_band *sband;
241         u32 basic_rates;
242         int i, j;
243         u16 beacon_int = cbss->beacon_interval;
244
245         lockdep_assert_held(&sdata->u.ibss.mtx);
246
247         if (beacon_int < 10)
248                 beacon_int = 10;
249
250         sband = sdata->local->hw.wiphy->bands[cbss->channel->band];
251
252         basic_rates = 0;
253
254         for (i = 0; i < bss->supp_rates_len; i++) {
255                 int rate = (bss->supp_rates[i] & 0x7f) * 5;
256                 bool is_basic = !!(bss->supp_rates[i] & 0x80);
257
258                 for (j = 0; j < sband->n_bitrates; j++) {
259                         if (sband->bitrates[j].bitrate == rate) {
260                                 if (is_basic)
261                                         basic_rates |= BIT(j);
262                                 break;
263                         }
264                 }
265         }
266
267         __ieee80211_sta_join_ibss(sdata, cbss->bssid,
268                                   beacon_int,
269                                   cbss->channel,
270                                   basic_rates,
271                                   cbss->capability,
272                                   cbss->tsf,
273                                   false);
274 }
275
276 static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta,
277                                                   bool auth)
278         __acquires(RCU)
279 {
280         struct ieee80211_sub_if_data *sdata = sta->sdata;
281         u8 addr[ETH_ALEN];
282
283         memcpy(addr, sta->sta.addr, ETH_ALEN);
284
285         ibss_dbg(sdata, "Adding new IBSS station %pM\n", addr);
286
287         sta_info_pre_move_state(sta, IEEE80211_STA_AUTH);
288         sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC);
289         /* authorize the station only if the network is not RSN protected. If
290          * not wait for the userspace to authorize it */
291         if (!sta->sdata->u.ibss.control_port)
292                 sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED);
293
294         rate_control_rate_init(sta);
295
296         /* If it fails, maybe we raced another insertion? */
297         if (sta_info_insert_rcu(sta))
298                 return sta_info_get(sdata, addr);
299         if (auth && !sdata->u.ibss.auth_frame_registrations) {
300                 ibss_dbg(sdata,
301                          "TX Auth SA=%pM DA=%pM BSSID=%pM (auth_transaction=1)\n",
302                          sdata->vif.addr, addr, sdata->u.ibss.bssid);
303                 ieee80211_send_auth(sdata, 1, WLAN_AUTH_OPEN, 0, NULL, 0,
304                                     addr, sdata->u.ibss.bssid, NULL, 0, 0);
305         }
306         return sta;
307 }
308
309 static struct sta_info *
310 ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata,
311                        const u8 *bssid, const u8 *addr,
312                        u32 supp_rates, bool auth)
313         __acquires(RCU)
314 {
315         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
316         struct ieee80211_local *local = sdata->local;
317         struct sta_info *sta;
318         struct ieee80211_chanctx_conf *chanctx_conf;
319         int band;
320
321         /*
322          * XXX: Consider removing the least recently used entry and
323          *      allow new one to be added.
324          */
325         if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
326                 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
327                                     sdata->name, addr);
328                 rcu_read_lock();
329                 return NULL;
330         }
331
332         if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) {
333                 rcu_read_lock();
334                 return NULL;
335         }
336
337         if (!ether_addr_equal(bssid, sdata->u.ibss.bssid)) {
338                 rcu_read_lock();
339                 return NULL;
340         }
341
342         rcu_read_lock();
343         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
344         if (WARN_ON_ONCE(!chanctx_conf))
345                 return NULL;
346         band = chanctx_conf->def.chan->band;
347         rcu_read_unlock();
348
349         sta = sta_info_alloc(sdata, addr, GFP_KERNEL);
350         if (!sta) {
351                 rcu_read_lock();
352                 return NULL;
353         }
354
355         sta->last_rx = jiffies;
356
357         /* make sure mandatory rates are always added */
358         sta->sta.supp_rates[band] = supp_rates |
359                         ieee80211_mandatory_rates(local, band);
360
361         return ieee80211_ibss_finish_sta(sta, auth);
362 }
363
364 static void ieee80211_rx_mgmt_deauth_ibss(struct ieee80211_sub_if_data *sdata,
365                                           struct ieee80211_mgmt *mgmt,
366                                           size_t len)
367 {
368         u16 reason = le16_to_cpu(mgmt->u.deauth.reason_code);
369
370         if (len < IEEE80211_DEAUTH_FRAME_LEN)
371                 return;
372
373         ibss_dbg(sdata, "RX DeAuth SA=%pM DA=%pM BSSID=%pM (reason: %d)\n",
374                  mgmt->sa, mgmt->da, mgmt->bssid, reason);
375         sta_info_destroy_addr(sdata, mgmt->sa);
376 }
377
378 static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata,
379                                         struct ieee80211_mgmt *mgmt,
380                                         size_t len)
381 {
382         u16 auth_alg, auth_transaction;
383         struct sta_info *sta;
384         u8 deauth_frame_buf[IEEE80211_DEAUTH_FRAME_LEN];
385
386         lockdep_assert_held(&sdata->u.ibss.mtx);
387
388         if (len < 24 + 6)
389                 return;
390
391         auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg);
392         auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction);
393
394         ibss_dbg(sdata,
395                  "RX Auth SA=%pM DA=%pM BSSID=%pM (auth_transaction=%d)\n",
396                  mgmt->sa, mgmt->da, mgmt->bssid, auth_transaction);
397
398         if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1)
399                 return;
400
401         sta_info_destroy_addr(sdata, mgmt->sa);
402         sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa, 0, false);
403         rcu_read_unlock();
404
405         /*
406          * if we have any problem in allocating the new station, we reply with a
407          * DEAUTH frame to tell the other end that we had a problem
408          */
409         if (!sta) {
410                 ieee80211_send_deauth_disassoc(sdata, sdata->u.ibss.bssid,
411                                                IEEE80211_STYPE_DEAUTH,
412                                                WLAN_REASON_UNSPECIFIED, true,
413                                                deauth_frame_buf);
414                 return;
415         }
416
417         /*
418          * IEEE 802.11 standard does not require authentication in IBSS
419          * networks and most implementations do not seem to use it.
420          * However, try to reply to authentication attempts if someone
421          * has actually implemented this.
422          */
423         ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, 0, NULL, 0,
424                             mgmt->sa, sdata->u.ibss.bssid, NULL, 0, 0);
425 }
426
427 static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
428                                   struct ieee80211_mgmt *mgmt,
429                                   size_t len,
430                                   struct ieee80211_rx_status *rx_status,
431                                   struct ieee802_11_elems *elems,
432                                   bool beacon)
433 {
434         struct ieee80211_local *local = sdata->local;
435         int freq;
436         struct cfg80211_bss *cbss;
437         struct ieee80211_bss *bss;
438         struct sta_info *sta;
439         struct ieee80211_channel *channel;
440         u64 beacon_timestamp, rx_timestamp;
441         u32 supp_rates = 0;
442         enum ieee80211_band band = rx_status->band;
443         struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band];
444         bool rates_updated = false;
445
446         if (elems->ds_params && elems->ds_params_len == 1)
447                 freq = ieee80211_channel_to_frequency(elems->ds_params[0],
448                                                       band);
449         else
450                 freq = rx_status->freq;
451
452         channel = ieee80211_get_channel(local->hw.wiphy, freq);
453
454         if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
455                 return;
456
457         if (sdata->vif.type == NL80211_IFTYPE_ADHOC &&
458             ether_addr_equal(mgmt->bssid, sdata->u.ibss.bssid)) {
459
460                 rcu_read_lock();
461                 sta = sta_info_get(sdata, mgmt->sa);
462
463                 if (elems->supp_rates) {
464                         supp_rates = ieee80211_sta_get_rates(local, elems,
465                                                              band, NULL);
466                         if (sta) {
467                                 u32 prev_rates;
468
469                                 prev_rates = sta->sta.supp_rates[band];
470                                 /* make sure mandatory rates are always added */
471                                 sta->sta.supp_rates[band] = supp_rates |
472                                         ieee80211_mandatory_rates(local, band);
473
474                                 if (sta->sta.supp_rates[band] != prev_rates) {
475                                         ibss_dbg(sdata,
476                                                  "updated supp_rates set for %pM based on beacon/probe_resp (0x%x -> 0x%x)\n",
477                                                  sta->sta.addr, prev_rates,
478                                                  sta->sta.supp_rates[band]);
479                                         rates_updated = true;
480                                 }
481                         } else {
482                                 rcu_read_unlock();
483                                 sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid,
484                                                 mgmt->sa, supp_rates, true);
485                         }
486                 }
487
488                 if (sta && elems->wmm_info)
489                         set_sta_flag(sta, WLAN_STA_WME);
490
491                 if (sta && elems->ht_operation && elems->ht_cap_elem &&
492                     sdata->u.ibss.channel_type != NL80211_CHAN_NO_HT) {
493                         /* we both use HT */
494                         struct ieee80211_sta_ht_cap sta_ht_cap_new;
495                         struct cfg80211_chan_def chandef;
496
497                         ieee80211_ht_oper_to_chandef(channel,
498                                                      elems->ht_operation,
499                                                      &chandef);
500
501                         ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband,
502                                                           elems->ht_cap_elem,
503                                                           &sta_ht_cap_new);
504
505                         /*
506                          * fall back to HT20 if we don't use or use
507                          * the other extension channel
508                          */
509                         if (chandef.width != NL80211_CHAN_WIDTH_40 ||
510                             cfg80211_get_chandef_type(&chandef) !=
511                                                 sdata->u.ibss.channel_type)
512                                 sta_ht_cap_new.cap &=
513                                         ~IEEE80211_HT_CAP_SUP_WIDTH_20_40;
514
515                         if (memcmp(&sta->sta.ht_cap, &sta_ht_cap_new,
516                                    sizeof(sta_ht_cap_new))) {
517                                 memcpy(&sta->sta.ht_cap, &sta_ht_cap_new,
518                                        sizeof(sta_ht_cap_new));
519                                 rates_updated = true;
520                         }
521                 }
522
523                 if (sta && rates_updated) {
524                         drv_sta_rc_update(local, sdata, &sta->sta,
525                                           IEEE80211_RC_SUPP_RATES_CHANGED);
526                         rate_control_rate_init(sta);
527                 }
528
529                 rcu_read_unlock();
530         }
531
532         bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems,
533                                         channel, beacon);
534         if (!bss)
535                 return;
536
537         cbss = container_of((void *)bss, struct cfg80211_bss, priv);
538
539         /* was just updated in ieee80211_bss_info_update */
540         beacon_timestamp = cbss->tsf;
541
542         /* check if we need to merge IBSS */
543
544         /* we use a fixed BSSID */
545         if (sdata->u.ibss.fixed_bssid)
546                 goto put_bss;
547
548         /* not an IBSS */
549         if (!(cbss->capability & WLAN_CAPABILITY_IBSS))
550                 goto put_bss;
551
552         /* different channel */
553         if (sdata->u.ibss.fixed_channel &&
554             sdata->u.ibss.channel != cbss->channel)
555                 goto put_bss;
556
557         /* different SSID */
558         if (elems->ssid_len != sdata->u.ibss.ssid_len ||
559             memcmp(elems->ssid, sdata->u.ibss.ssid,
560                                 sdata->u.ibss.ssid_len))
561                 goto put_bss;
562
563         /* same BSSID */
564         if (ether_addr_equal(cbss->bssid, sdata->u.ibss.bssid))
565                 goto put_bss;
566
567         if (ieee80211_have_rx_timestamp(rx_status)) {
568                 /* time when timestamp field was received */
569                 rx_timestamp =
570                         ieee80211_calculate_rx_timestamp(local, rx_status,
571                                                          len + FCS_LEN, 24);
572         } else {
573                 /*
574                  * second best option: get current TSF
575                  * (will return -1 if not supported)
576                  */
577                 rx_timestamp = drv_get_tsf(local, sdata);
578         }
579
580         ibss_dbg(sdata,
581                  "RX beacon SA=%pM BSSID=%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n",
582                  mgmt->sa, mgmt->bssid,
583                  (unsigned long long)rx_timestamp,
584                  (unsigned long long)beacon_timestamp,
585                  (unsigned long long)(rx_timestamp - beacon_timestamp),
586                  jiffies);
587
588         if (beacon_timestamp > rx_timestamp) {
589                 ibss_dbg(sdata,
590                          "beacon TSF higher than local TSF - IBSS merge with BSSID %pM\n",
591                          mgmt->bssid);
592                 ieee80211_sta_join_ibss(sdata, bss);
593                 supp_rates = ieee80211_sta_get_rates(local, elems, band, NULL);
594                 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
595                                        supp_rates, true);
596                 rcu_read_unlock();
597         }
598
599  put_bss:
600         ieee80211_rx_bss_put(local, bss);
601 }
602
603 void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata,
604                               const u8 *bssid, const u8 *addr,
605                               u32 supp_rates)
606 {
607         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
608         struct ieee80211_local *local = sdata->local;
609         struct sta_info *sta;
610         struct ieee80211_chanctx_conf *chanctx_conf;
611         int band;
612
613         /*
614          * XXX: Consider removing the least recently used entry and
615          *      allow new one to be added.
616          */
617         if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
618                 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
619                                     sdata->name, addr);
620                 return;
621         }
622
623         if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH)
624                 return;
625
626         if (!ether_addr_equal(bssid, sdata->u.ibss.bssid))
627                 return;
628
629         rcu_read_lock();
630         chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
631         if (WARN_ON_ONCE(!chanctx_conf)) {
632                 rcu_read_unlock();
633                 return;
634         }
635         band = chanctx_conf->def.chan->band;
636         rcu_read_unlock();
637
638         sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
639         if (!sta)
640                 return;
641
642         sta->last_rx = jiffies;
643
644         /* make sure mandatory rates are always added */
645         sta->sta.supp_rates[band] = supp_rates |
646                         ieee80211_mandatory_rates(local, band);
647
648         spin_lock(&ifibss->incomplete_lock);
649         list_add(&sta->list, &ifibss->incomplete_stations);
650         spin_unlock(&ifibss->incomplete_lock);
651         ieee80211_queue_work(&local->hw, &sdata->work);
652 }
653
654 static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata)
655 {
656         struct ieee80211_local *local = sdata->local;
657         int active = 0;
658         struct sta_info *sta;
659
660         lockdep_assert_held(&sdata->u.ibss.mtx);
661
662         rcu_read_lock();
663
664         list_for_each_entry_rcu(sta, &local->sta_list, list) {
665                 if (sta->sdata == sdata &&
666                     time_after(sta->last_rx + IEEE80211_IBSS_MERGE_INTERVAL,
667                                jiffies)) {
668                         active++;
669                         break;
670                 }
671         }
672
673         rcu_read_unlock();
674
675         return active;
676 }
677
678 /*
679  * This function is called with state == IEEE80211_IBSS_MLME_JOINED
680  */
681
682 static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata)
683 {
684         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
685
686         lockdep_assert_held(&ifibss->mtx);
687
688         mod_timer(&ifibss->timer,
689                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
690
691         ieee80211_sta_expire(sdata, IEEE80211_IBSS_INACTIVITY_LIMIT);
692
693         if (time_before(jiffies, ifibss->last_scan_completed +
694                        IEEE80211_IBSS_MERGE_INTERVAL))
695                 return;
696
697         if (ieee80211_sta_active_ibss(sdata))
698                 return;
699
700         if (ifibss->fixed_channel)
701                 return;
702
703         sdata_info(sdata,
704                    "No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge)\n");
705
706         ieee80211_request_ibss_scan(sdata, ifibss->ssid, ifibss->ssid_len,
707                                     NULL);
708 }
709
710 static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata)
711 {
712         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
713         u8 bssid[ETH_ALEN];
714         u16 capability;
715         int i;
716
717         lockdep_assert_held(&ifibss->mtx);
718
719         if (ifibss->fixed_bssid) {
720                 memcpy(bssid, ifibss->bssid, ETH_ALEN);
721         } else {
722                 /* Generate random, not broadcast, locally administered BSSID. Mix in
723                  * own MAC address to make sure that devices that do not have proper
724                  * random number generator get different BSSID. */
725                 get_random_bytes(bssid, ETH_ALEN);
726                 for (i = 0; i < ETH_ALEN; i++)
727                         bssid[i] ^= sdata->vif.addr[i];
728                 bssid[0] &= ~0x01;
729                 bssid[0] |= 0x02;
730         }
731
732         sdata_info(sdata, "Creating new IBSS network, BSSID %pM\n", bssid);
733
734         capability = WLAN_CAPABILITY_IBSS;
735
736         if (ifibss->privacy)
737                 capability |= WLAN_CAPABILITY_PRIVACY;
738         else
739                 sdata->drop_unencrypted = 0;
740
741         __ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int,
742                                   ifibss->channel, ifibss->basic_rates,
743                                   capability, 0, true);
744 }
745
746 /*
747  * This function is called with state == IEEE80211_IBSS_MLME_SEARCH
748  */
749
750 static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata)
751 {
752         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
753         struct ieee80211_local *local = sdata->local;
754         struct cfg80211_bss *cbss;
755         struct ieee80211_channel *chan = NULL;
756         const u8 *bssid = NULL;
757         int active_ibss;
758         u16 capability;
759
760         lockdep_assert_held(&ifibss->mtx);
761
762         active_ibss = ieee80211_sta_active_ibss(sdata);
763         ibss_dbg(sdata, "sta_find_ibss (active_ibss=%d)\n", active_ibss);
764
765         if (active_ibss)
766                 return;
767
768         capability = WLAN_CAPABILITY_IBSS;
769         if (ifibss->privacy)
770                 capability |= WLAN_CAPABILITY_PRIVACY;
771         if (ifibss->fixed_bssid)
772                 bssid = ifibss->bssid;
773         if (ifibss->fixed_channel)
774                 chan = ifibss->channel;
775         if (!is_zero_ether_addr(ifibss->bssid))
776                 bssid = ifibss->bssid;
777         cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid,
778                                 ifibss->ssid, ifibss->ssid_len,
779                                 WLAN_CAPABILITY_IBSS | WLAN_CAPABILITY_PRIVACY,
780                                 capability);
781
782         if (cbss) {
783                 struct ieee80211_bss *bss;
784
785                 bss = (void *)cbss->priv;
786                 ibss_dbg(sdata,
787                          "sta_find_ibss: selected %pM current %pM\n",
788                          cbss->bssid, ifibss->bssid);
789                 sdata_info(sdata,
790                            "Selected IBSS BSSID %pM based on configured SSID\n",
791                            cbss->bssid);
792
793                 ieee80211_sta_join_ibss(sdata, bss);
794                 ieee80211_rx_bss_put(local, bss);
795                 return;
796         }
797
798         ibss_dbg(sdata, "sta_find_ibss: did not try to join ibss\n");
799
800         /* Selected IBSS not found in current scan results - try to scan */
801         if (time_after(jiffies, ifibss->last_scan_completed +
802                                         IEEE80211_SCAN_INTERVAL)) {
803                 sdata_info(sdata, "Trigger new scan to find an IBSS to join\n");
804
805                 ieee80211_request_ibss_scan(sdata, ifibss->ssid,
806                                             ifibss->ssid_len, chan);
807         } else {
808                 int interval = IEEE80211_SCAN_INTERVAL;
809
810                 if (time_after(jiffies, ifibss->ibss_join_req +
811                                IEEE80211_IBSS_JOIN_TIMEOUT))
812                         ieee80211_sta_create_ibss(sdata);
813
814                 mod_timer(&ifibss->timer,
815                           round_jiffies(jiffies + interval));
816         }
817 }
818
819 static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata,
820                                         struct sk_buff *req)
821 {
822         struct ieee80211_mgmt *mgmt = (void *)req->data;
823         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
824         struct ieee80211_local *local = sdata->local;
825         int tx_last_beacon, len = req->len;
826         struct sk_buff *skb;
827         struct ieee80211_mgmt *resp;
828         struct sk_buff *presp;
829         u8 *pos, *end;
830
831         lockdep_assert_held(&ifibss->mtx);
832
833         presp = rcu_dereference_protected(ifibss->presp,
834                                           lockdep_is_held(&ifibss->mtx));
835
836         if (ifibss->state != IEEE80211_IBSS_MLME_JOINED ||
837             len < 24 + 2 || !presp)
838                 return;
839
840         tx_last_beacon = drv_tx_last_beacon(local);
841
842         ibss_dbg(sdata,
843                  "RX ProbeReq SA=%pM DA=%pM BSSID=%pM (tx_last_beacon=%d)\n",
844                  mgmt->sa, mgmt->da, mgmt->bssid, tx_last_beacon);
845
846         if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da))
847                 return;
848
849         if (!ether_addr_equal(mgmt->bssid, ifibss->bssid) &&
850             !is_broadcast_ether_addr(mgmt->bssid))
851                 return;
852
853         end = ((u8 *) mgmt) + len;
854         pos = mgmt->u.probe_req.variable;
855         if (pos[0] != WLAN_EID_SSID ||
856             pos + 2 + pos[1] > end) {
857                 ibss_dbg(sdata, "Invalid SSID IE in ProbeReq from %pM\n",
858                          mgmt->sa);
859                 return;
860         }
861         if (pos[1] != 0 &&
862             (pos[1] != ifibss->ssid_len ||
863              memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) {
864                 /* Ignore ProbeReq for foreign SSID */
865                 return;
866         }
867
868         /* Reply with ProbeResp */
869         skb = skb_copy(presp, GFP_KERNEL);
870         if (!skb)
871                 return;
872
873         resp = (struct ieee80211_mgmt *) skb->data;
874         memcpy(resp->da, mgmt->sa, ETH_ALEN);
875         ibss_dbg(sdata, "Sending ProbeResp to %pM\n", resp->da);
876         IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
877         ieee80211_tx_skb(sdata, skb);
878 }
879
880 static void ieee80211_rx_mgmt_probe_resp(struct ieee80211_sub_if_data *sdata,
881                                          struct ieee80211_mgmt *mgmt,
882                                          size_t len,
883                                          struct ieee80211_rx_status *rx_status)
884 {
885         size_t baselen;
886         struct ieee802_11_elems elems;
887
888         baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
889         if (baselen > len)
890                 return;
891
892         ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
893                                 &elems);
894
895         ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, false);
896 }
897
898 static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata,
899                                      struct ieee80211_mgmt *mgmt,
900                                      size_t len,
901                                      struct ieee80211_rx_status *rx_status)
902 {
903         size_t baselen;
904         struct ieee802_11_elems elems;
905
906         /* Process beacon from the current BSS */
907         baselen = (u8 *) mgmt->u.beacon.variable - (u8 *) mgmt;
908         if (baselen > len)
909                 return;
910
911         ieee802_11_parse_elems(mgmt->u.beacon.variable, len - baselen, &elems);
912
913         ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, true);
914 }
915
916 void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
917                                    struct sk_buff *skb)
918 {
919         struct ieee80211_rx_status *rx_status;
920         struct ieee80211_mgmt *mgmt;
921         u16 fc;
922
923         rx_status = IEEE80211_SKB_RXCB(skb);
924         mgmt = (struct ieee80211_mgmt *) skb->data;
925         fc = le16_to_cpu(mgmt->frame_control);
926
927         mutex_lock(&sdata->u.ibss.mtx);
928
929         if (!sdata->u.ibss.ssid_len)
930                 goto mgmt_out; /* not ready to merge yet */
931
932         switch (fc & IEEE80211_FCTL_STYPE) {
933         case IEEE80211_STYPE_PROBE_REQ:
934                 ieee80211_rx_mgmt_probe_req(sdata, skb);
935                 break;
936         case IEEE80211_STYPE_PROBE_RESP:
937                 ieee80211_rx_mgmt_probe_resp(sdata, mgmt, skb->len,
938                                              rx_status);
939                 break;
940         case IEEE80211_STYPE_BEACON:
941                 ieee80211_rx_mgmt_beacon(sdata, mgmt, skb->len,
942                                          rx_status);
943                 break;
944         case IEEE80211_STYPE_AUTH:
945                 ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len);
946                 break;
947         case IEEE80211_STYPE_DEAUTH:
948                 ieee80211_rx_mgmt_deauth_ibss(sdata, mgmt, skb->len);
949                 break;
950         }
951
952  mgmt_out:
953         mutex_unlock(&sdata->u.ibss.mtx);
954 }
955
956 void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata)
957 {
958         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
959         struct sta_info *sta;
960
961         mutex_lock(&ifibss->mtx);
962
963         /*
964          * Work could be scheduled after scan or similar
965          * when we aren't even joined (or trying) with a
966          * network.
967          */
968         if (!ifibss->ssid_len)
969                 goto out;
970
971         spin_lock_bh(&ifibss->incomplete_lock);
972         while (!list_empty(&ifibss->incomplete_stations)) {
973                 sta = list_first_entry(&ifibss->incomplete_stations,
974                                        struct sta_info, list);
975                 list_del(&sta->list);
976                 spin_unlock_bh(&ifibss->incomplete_lock);
977
978                 ieee80211_ibss_finish_sta(sta, true);
979                 rcu_read_unlock();
980                 spin_lock_bh(&ifibss->incomplete_lock);
981         }
982         spin_unlock_bh(&ifibss->incomplete_lock);
983
984         switch (ifibss->state) {
985         case IEEE80211_IBSS_MLME_SEARCH:
986                 ieee80211_sta_find_ibss(sdata);
987                 break;
988         case IEEE80211_IBSS_MLME_JOINED:
989                 ieee80211_sta_merge_ibss(sdata);
990                 break;
991         default:
992                 WARN_ON(1);
993                 break;
994         }
995
996  out:
997         mutex_unlock(&ifibss->mtx);
998 }
999
1000 static void ieee80211_ibss_timer(unsigned long data)
1001 {
1002         struct ieee80211_sub_if_data *sdata =
1003                 (struct ieee80211_sub_if_data *) data;
1004         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1005         struct ieee80211_local *local = sdata->local;
1006
1007         if (local->quiescing) {
1008                 ifibss->timer_running = true;
1009                 return;
1010         }
1011
1012         ieee80211_queue_work(&local->hw, &sdata->work);
1013 }
1014
1015 #ifdef CONFIG_PM
1016 void ieee80211_ibss_quiesce(struct ieee80211_sub_if_data *sdata)
1017 {
1018         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1019
1020         if (del_timer_sync(&ifibss->timer))
1021                 ifibss->timer_running = true;
1022 }
1023
1024 void ieee80211_ibss_restart(struct ieee80211_sub_if_data *sdata)
1025 {
1026         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1027
1028         if (ifibss->timer_running) {
1029                 add_timer(&ifibss->timer);
1030                 ifibss->timer_running = false;
1031         }
1032 }
1033 #endif
1034
1035 void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata)
1036 {
1037         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1038
1039         setup_timer(&ifibss->timer, ieee80211_ibss_timer,
1040                     (unsigned long) sdata);
1041         mutex_init(&ifibss->mtx);
1042         INIT_LIST_HEAD(&ifibss->incomplete_stations);
1043         spin_lock_init(&ifibss->incomplete_lock);
1044 }
1045
1046 /* scan finished notification */
1047 void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local)
1048 {
1049         struct ieee80211_sub_if_data *sdata;
1050
1051         mutex_lock(&local->iflist_mtx);
1052         list_for_each_entry(sdata, &local->interfaces, list) {
1053                 if (!ieee80211_sdata_running(sdata))
1054                         continue;
1055                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1056                         continue;
1057                 sdata->u.ibss.last_scan_completed = jiffies;
1058                 ieee80211_queue_work(&local->hw, &sdata->work);
1059         }
1060         mutex_unlock(&local->iflist_mtx);
1061 }
1062
1063 int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
1064                         struct cfg80211_ibss_params *params)
1065 {
1066         struct sk_buff *skb;
1067         u32 changed = 0;
1068
1069         skb = dev_alloc_skb(sdata->local->hw.extra_tx_headroom +
1070                             sizeof(struct ieee80211_hdr_3addr) +
1071                             12 /* struct ieee80211_mgmt.u.beacon */ +
1072                             2 + IEEE80211_MAX_SSID_LEN /* max SSID */ +
1073                             2 + 8 /* max Supported Rates */ +
1074                             3 /* max DS params */ +
1075                             4 /* IBSS params */ +
1076                             2 + (IEEE80211_MAX_SUPP_RATES - 8) +
1077                             2 + sizeof(struct ieee80211_ht_cap) +
1078                             2 + sizeof(struct ieee80211_ht_operation) +
1079                             params->ie_len);
1080         if (!skb)
1081                 return -ENOMEM;
1082
1083         mutex_lock(&sdata->u.ibss.mtx);
1084
1085         if (params->bssid) {
1086                 memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN);
1087                 sdata->u.ibss.fixed_bssid = true;
1088         } else
1089                 sdata->u.ibss.fixed_bssid = false;
1090
1091         sdata->u.ibss.privacy = params->privacy;
1092         sdata->u.ibss.control_port = params->control_port;
1093         sdata->u.ibss.basic_rates = params->basic_rates;
1094         memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate,
1095                sizeof(params->mcast_rate));
1096
1097         sdata->vif.bss_conf.beacon_int = params->beacon_interval;
1098
1099         sdata->u.ibss.channel = params->chandef.chan;
1100         sdata->u.ibss.channel_type =
1101                 cfg80211_get_chandef_type(&params->chandef);
1102         sdata->u.ibss.fixed_channel = params->channel_fixed;
1103
1104         if (params->ie) {
1105                 sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len,
1106                                            GFP_KERNEL);
1107                 if (sdata->u.ibss.ie)
1108                         sdata->u.ibss.ie_len = params->ie_len;
1109         }
1110
1111         sdata->u.ibss.skb = skb;
1112         sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
1113         sdata->u.ibss.ibss_join_req = jiffies;
1114
1115         memcpy(sdata->u.ibss.ssid, params->ssid, params->ssid_len);
1116         sdata->u.ibss.ssid_len = params->ssid_len;
1117
1118         mutex_unlock(&sdata->u.ibss.mtx);
1119
1120         mutex_lock(&sdata->local->mtx);
1121         ieee80211_recalc_idle(sdata->local);
1122         mutex_unlock(&sdata->local->mtx);
1123
1124         /*
1125          * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is
1126          * reserved, but an HT STA shall protect HT transmissions as though
1127          * the HT Protection field were set to non-HT mixed mode.
1128          *
1129          * In an IBSS, the RIFS Mode field of the HT Operation element is
1130          * also reserved, but an HT STA shall operate as though this field
1131          * were set to 1.
1132          */
1133
1134         sdata->vif.bss_conf.ht_operation_mode |=
1135                   IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED
1136                 | IEEE80211_HT_PARAM_RIFS_MODE;
1137
1138         changed |= BSS_CHANGED_HT;
1139         ieee80211_bss_info_change_notify(sdata, changed);
1140
1141         sdata->smps_mode = IEEE80211_SMPS_OFF;
1142         sdata->needed_rx_chains = sdata->local->rx_chains;
1143
1144         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1145
1146         return 0;
1147 }
1148
1149 int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata)
1150 {
1151         struct sk_buff *skb;
1152         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1153         struct ieee80211_local *local = sdata->local;
1154         struct cfg80211_bss *cbss;
1155         u16 capability;
1156         int active_ibss;
1157         struct sta_info *sta;
1158
1159         mutex_lock(&sdata->u.ibss.mtx);
1160
1161         active_ibss = ieee80211_sta_active_ibss(sdata);
1162
1163         if (!active_ibss && !is_zero_ether_addr(ifibss->bssid)) {
1164                 capability = WLAN_CAPABILITY_IBSS;
1165
1166                 if (ifibss->privacy)
1167                         capability |= WLAN_CAPABILITY_PRIVACY;
1168
1169                 cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->channel,
1170                                         ifibss->bssid, ifibss->ssid,
1171                                         ifibss->ssid_len, WLAN_CAPABILITY_IBSS |
1172                                         WLAN_CAPABILITY_PRIVACY,
1173                                         capability);
1174
1175                 if (cbss) {
1176                         cfg80211_unlink_bss(local->hw.wiphy, cbss);
1177                         cfg80211_put_bss(cbss);
1178                 }
1179         }
1180
1181         ifibss->state = IEEE80211_IBSS_MLME_SEARCH;
1182         memset(ifibss->bssid, 0, ETH_ALEN);
1183         ifibss->ssid_len = 0;
1184
1185         sta_info_flush(sdata->local, sdata);
1186
1187         spin_lock_bh(&ifibss->incomplete_lock);
1188         while (!list_empty(&ifibss->incomplete_stations)) {
1189                 sta = list_first_entry(&ifibss->incomplete_stations,
1190                                        struct sta_info, list);
1191                 list_del(&sta->list);
1192                 spin_unlock_bh(&ifibss->incomplete_lock);
1193
1194                 sta_info_free(local, sta);
1195                 spin_lock_bh(&ifibss->incomplete_lock);
1196         }
1197         spin_unlock_bh(&ifibss->incomplete_lock);
1198
1199         netif_carrier_off(sdata->dev);
1200
1201         /* remove beacon */
1202         kfree(sdata->u.ibss.ie);
1203         skb = rcu_dereference_protected(sdata->u.ibss.presp,
1204                                         lockdep_is_held(&sdata->u.ibss.mtx));
1205         RCU_INIT_POINTER(sdata->u.ibss.presp, NULL);
1206         sdata->vif.bss_conf.ibss_joined = false;
1207         sdata->vif.bss_conf.ibss_creator = false;
1208         ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED |
1209                                                 BSS_CHANGED_IBSS);
1210         synchronize_rcu();
1211         kfree_skb(skb);
1212
1213         skb_queue_purge(&sdata->skb_queue);
1214
1215         del_timer_sync(&sdata->u.ibss.timer);
1216
1217         mutex_unlock(&sdata->u.ibss.mtx);
1218
1219         mutex_lock(&local->mtx);
1220         ieee80211_recalc_idle(sdata->local);
1221         mutex_unlock(&local->mtx);
1222
1223         return 0;
1224 }