xref: /linux/net/wireless/scan.c (revision 02680c23d7b3febe45ea3d4f9818c2b2dc89020a)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * cfg80211 scan result handling
4  *
5  * Copyright 2008 Johannes Berg <johannes@sipsolutions.net>
6  * Copyright 2013-2014  Intel Mobile Communications GmbH
7  * Copyright 2016	Intel Deutschland GmbH
8  * Copyright (C) 2018-2020 Intel Corporation
9  */
10 #include <linux/kernel.h>
11 #include <linux/slab.h>
12 #include <linux/module.h>
13 #include <linux/netdevice.h>
14 #include <linux/wireless.h>
15 #include <linux/nl80211.h>
16 #include <linux/etherdevice.h>
17 #include <linux/crc32.h>
18 #include <linux/bitfield.h>
19 #include <net/arp.h>
20 #include <net/cfg80211.h>
21 #include <net/cfg80211-wext.h>
22 #include <net/iw_handler.h>
23 #include "core.h"
24 #include "nl80211.h"
25 #include "wext-compat.h"
26 #include "rdev-ops.h"
27 
28 /**
29  * DOC: BSS tree/list structure
30  *
31  * At the top level, the BSS list is kept in both a list in each
32  * registered device (@bss_list) as well as an RB-tree for faster
33  * lookup. In the RB-tree, entries can be looked up using their
34  * channel, MESHID, MESHCONF (for MBSSes) or channel, BSSID, SSID
35  * for other BSSes.
36  *
37  * Due to the possibility of hidden SSIDs, there's a second level
38  * structure, the "hidden_list" and "hidden_beacon_bss" pointer.
39  * The hidden_list connects all BSSes belonging to a single AP
40  * that has a hidden SSID, and connects beacon and probe response
41  * entries. For a probe response entry for a hidden SSID, the
42  * hidden_beacon_bss pointer points to the BSS struct holding the
43  * beacon's information.
44  *
45  * Reference counting is done for all these references except for
46  * the hidden_list, so that a beacon BSS struct that is otherwise
47  * not referenced has one reference for being on the bss_list and
48  * one for each probe response entry that points to it using the
49  * hidden_beacon_bss pointer. When a BSS struct that has such a
50  * pointer is get/put, the refcount update is also propagated to
51  * the referenced struct, this ensure that it cannot get removed
52  * while somebody is using the probe response version.
53  *
54  * Note that the hidden_beacon_bss pointer never changes, due to
55  * the reference counting. Therefore, no locking is needed for
56  * it.
57  *
58  * Also note that the hidden_beacon_bss pointer is only relevant
59  * if the driver uses something other than the IEs, e.g. private
60  * data stored in the BSS struct, since the beacon IEs are
61  * also linked into the probe response struct.
62  */
63 
64 /*
65  * Limit the number of BSS entries stored in mac80211. Each one is
66  * a bit over 4k at most, so this limits to roughly 4-5M of memory.
67  * If somebody wants to really attack this though, they'd likely
68  * use small beacons, and only one type of frame, limiting each of
69  * the entries to a much smaller size (in order to generate more
70  * entries in total, so overhead is bigger.)
71  */
72 static int bss_entries_limit = 1000;
73 module_param(bss_entries_limit, int, 0644);
74 MODULE_PARM_DESC(bss_entries_limit,
75                  "limit to number of scan BSS entries (per wiphy, default 1000)");
76 
77 #define IEEE80211_SCAN_RESULT_EXPIRE	(30 * HZ)
78 
79 /**
80  * struct cfg80211_colocated_ap - colocated AP information
81  *
82  * @list: linked list to all colocated aPS
83  * @bssid: BSSID of the reported AP
84  * @ssid: SSID of the reported AP
85  * @ssid_len: length of the ssid
86  * @center_freq: frequency the reported AP is on
87  * @unsolicited_probe: the reported AP is part of an ESS, where all the APs
88  *	that operate in the same channel as the reported AP and that might be
89  *	detected by a STA receiving this frame, are transmitting unsolicited
90  *	Probe Response frames every 20 TUs
91  * @oct_recommended: OCT is recommended to exchange MMPDUs with the reported AP
92  * @same_ssid: the reported AP has the same SSID as the reporting AP
93  * @multi_bss: the reported AP is part of a multiple BSSID set
94  * @transmitted_bssid: the reported AP is the transmitting BSSID
95  * @colocated_ess: all the APs that share the same ESS as the reported AP are
96  *	colocated and can be discovered via legacy bands.
97  * @short_ssid_valid: short_ssid is valid and can be used
98  * @short_ssid: the short SSID for this SSID
99  */
100 struct cfg80211_colocated_ap {
101 	struct list_head list;
102 	u8 bssid[ETH_ALEN];
103 	u8 ssid[IEEE80211_MAX_SSID_LEN];
104 	size_t ssid_len;
105 	u32 short_ssid;
106 	u32 center_freq;
107 	u8 unsolicited_probe:1,
108 	   oct_recommended:1,
109 	   same_ssid:1,
110 	   multi_bss:1,
111 	   transmitted_bssid:1,
112 	   colocated_ess:1,
113 	   short_ssid_valid:1;
114 };
115 
116 static void bss_free(struct cfg80211_internal_bss *bss)
117 {
118 	struct cfg80211_bss_ies *ies;
119 
120 	if (WARN_ON(atomic_read(&bss->hold)))
121 		return;
122 
123 	ies = (void *)rcu_access_pointer(bss->pub.beacon_ies);
124 	if (ies && !bss->pub.hidden_beacon_bss)
125 		kfree_rcu(ies, rcu_head);
126 	ies = (void *)rcu_access_pointer(bss->pub.proberesp_ies);
127 	if (ies)
128 		kfree_rcu(ies, rcu_head);
129 
130 	/*
131 	 * This happens when the module is removed, it doesn't
132 	 * really matter any more save for completeness
133 	 */
134 	if (!list_empty(&bss->hidden_list))
135 		list_del(&bss->hidden_list);
136 
137 	kfree(bss);
138 }
139 
140 static inline void bss_ref_get(struct cfg80211_registered_device *rdev,
141 			       struct cfg80211_internal_bss *bss)
142 {
143 	lockdep_assert_held(&rdev->bss_lock);
144 
145 	bss->refcount++;
146 	if (bss->pub.hidden_beacon_bss) {
147 		bss = container_of(bss->pub.hidden_beacon_bss,
148 				   struct cfg80211_internal_bss,
149 				   pub);
150 		bss->refcount++;
151 	}
152 	if (bss->pub.transmitted_bss) {
153 		bss = container_of(bss->pub.transmitted_bss,
154 				   struct cfg80211_internal_bss,
155 				   pub);
156 		bss->refcount++;
157 	}
158 }
159 
160 static inline void bss_ref_put(struct cfg80211_registered_device *rdev,
161 			       struct cfg80211_internal_bss *bss)
162 {
163 	lockdep_assert_held(&rdev->bss_lock);
164 
165 	if (bss->pub.hidden_beacon_bss) {
166 		struct cfg80211_internal_bss *hbss;
167 		hbss = container_of(bss->pub.hidden_beacon_bss,
168 				    struct cfg80211_internal_bss,
169 				    pub);
170 		hbss->refcount--;
171 		if (hbss->refcount == 0)
172 			bss_free(hbss);
173 	}
174 
175 	if (bss->pub.transmitted_bss) {
176 		struct cfg80211_internal_bss *tbss;
177 
178 		tbss = container_of(bss->pub.transmitted_bss,
179 				    struct cfg80211_internal_bss,
180 				    pub);
181 		tbss->refcount--;
182 		if (tbss->refcount == 0)
183 			bss_free(tbss);
184 	}
185 
186 	bss->refcount--;
187 	if (bss->refcount == 0)
188 		bss_free(bss);
189 }
190 
191 static bool __cfg80211_unlink_bss(struct cfg80211_registered_device *rdev,
192 				  struct cfg80211_internal_bss *bss)
193 {
194 	lockdep_assert_held(&rdev->bss_lock);
195 
196 	if (!list_empty(&bss->hidden_list)) {
197 		/*
198 		 * don't remove the beacon entry if it has
199 		 * probe responses associated with it
200 		 */
201 		if (!bss->pub.hidden_beacon_bss)
202 			return false;
203 		/*
204 		 * if it's a probe response entry break its
205 		 * link to the other entries in the group
206 		 */
207 		list_del_init(&bss->hidden_list);
208 	}
209 
210 	list_del_init(&bss->list);
211 	list_del_init(&bss->pub.nontrans_list);
212 	rb_erase(&bss->rbn, &rdev->bss_tree);
213 	rdev->bss_entries--;
214 	WARN_ONCE((rdev->bss_entries == 0) ^ list_empty(&rdev->bss_list),
215 		  "rdev bss entries[%d]/list[empty:%d] corruption\n",
216 		  rdev->bss_entries, list_empty(&rdev->bss_list));
217 	bss_ref_put(rdev, bss);
218 	return true;
219 }
220 
221 bool cfg80211_is_element_inherited(const struct element *elem,
222 				   const struct element *non_inherit_elem)
223 {
224 	u8 id_len, ext_id_len, i, loop_len, id;
225 	const u8 *list;
226 
227 	if (elem->id == WLAN_EID_MULTIPLE_BSSID)
228 		return false;
229 
230 	if (!non_inherit_elem || non_inherit_elem->datalen < 2)
231 		return true;
232 
233 	/*
234 	 * non inheritance element format is:
235 	 * ext ID (56) | IDs list len | list | extension IDs list len | list
236 	 * Both lists are optional. Both lengths are mandatory.
237 	 * This means valid length is:
238 	 * elem_len = 1 (extension ID) + 2 (list len fields) + list lengths
239 	 */
240 	id_len = non_inherit_elem->data[1];
241 	if (non_inherit_elem->datalen < 3 + id_len)
242 		return true;
243 
244 	ext_id_len = non_inherit_elem->data[2 + id_len];
245 	if (non_inherit_elem->datalen < 3 + id_len + ext_id_len)
246 		return true;
247 
248 	if (elem->id == WLAN_EID_EXTENSION) {
249 		if (!ext_id_len)
250 			return true;
251 		loop_len = ext_id_len;
252 		list = &non_inherit_elem->data[3 + id_len];
253 		id = elem->data[0];
254 	} else {
255 		if (!id_len)
256 			return true;
257 		loop_len = id_len;
258 		list = &non_inherit_elem->data[2];
259 		id = elem->id;
260 	}
261 
262 	for (i = 0; i < loop_len; i++) {
263 		if (list[i] == id)
264 			return false;
265 	}
266 
267 	return true;
268 }
269 EXPORT_SYMBOL(cfg80211_is_element_inherited);
270 
271 static size_t cfg80211_gen_new_ie(const u8 *ie, size_t ielen,
272 				  const u8 *subelement, size_t subie_len,
273 				  u8 *new_ie, gfp_t gfp)
274 {
275 	u8 *pos, *tmp;
276 	const u8 *tmp_old, *tmp_new;
277 	const struct element *non_inherit_elem;
278 	u8 *sub_copy;
279 
280 	/* copy subelement as we need to change its content to
281 	 * mark an ie after it is processed.
282 	 */
283 	sub_copy = kmemdup(subelement, subie_len, gfp);
284 	if (!sub_copy)
285 		return 0;
286 
287 	pos = &new_ie[0];
288 
289 	/* set new ssid */
290 	tmp_new = cfg80211_find_ie(WLAN_EID_SSID, sub_copy, subie_len);
291 	if (tmp_new) {
292 		memcpy(pos, tmp_new, tmp_new[1] + 2);
293 		pos += (tmp_new[1] + 2);
294 	}
295 
296 	/* get non inheritance list if exists */
297 	non_inherit_elem =
298 		cfg80211_find_ext_elem(WLAN_EID_EXT_NON_INHERITANCE,
299 				       sub_copy, subie_len);
300 
301 	/* go through IEs in ie (skip SSID) and subelement,
302 	 * merge them into new_ie
303 	 */
304 	tmp_old = cfg80211_find_ie(WLAN_EID_SSID, ie, ielen);
305 	tmp_old = (tmp_old) ? tmp_old + tmp_old[1] + 2 : ie;
306 
307 	while (tmp_old + tmp_old[1] + 2 - ie <= ielen) {
308 		if (tmp_old[0] == 0) {
309 			tmp_old++;
310 			continue;
311 		}
312 
313 		if (tmp_old[0] == WLAN_EID_EXTENSION)
314 			tmp = (u8 *)cfg80211_find_ext_ie(tmp_old[2], sub_copy,
315 							 subie_len);
316 		else
317 			tmp = (u8 *)cfg80211_find_ie(tmp_old[0], sub_copy,
318 						     subie_len);
319 
320 		if (!tmp) {
321 			const struct element *old_elem = (void *)tmp_old;
322 
323 			/* ie in old ie but not in subelement */
324 			if (cfg80211_is_element_inherited(old_elem,
325 							  non_inherit_elem)) {
326 				memcpy(pos, tmp_old, tmp_old[1] + 2);
327 				pos += tmp_old[1] + 2;
328 			}
329 		} else {
330 			/* ie in transmitting ie also in subelement,
331 			 * copy from subelement and flag the ie in subelement
332 			 * as copied (by setting eid field to WLAN_EID_SSID,
333 			 * which is skipped anyway).
334 			 * For vendor ie, compare OUI + type + subType to
335 			 * determine if they are the same ie.
336 			 */
337 			if (tmp_old[0] == WLAN_EID_VENDOR_SPECIFIC) {
338 				if (!memcmp(tmp_old + 2, tmp + 2, 5)) {
339 					/* same vendor ie, copy from
340 					 * subelement
341 					 */
342 					memcpy(pos, tmp, tmp[1] + 2);
343 					pos += tmp[1] + 2;
344 					tmp[0] = WLAN_EID_SSID;
345 				} else {
346 					memcpy(pos, tmp_old, tmp_old[1] + 2);
347 					pos += tmp_old[1] + 2;
348 				}
349 			} else {
350 				/* copy ie from subelement into new ie */
351 				memcpy(pos, tmp, tmp[1] + 2);
352 				pos += tmp[1] + 2;
353 				tmp[0] = WLAN_EID_SSID;
354 			}
355 		}
356 
357 		if (tmp_old + tmp_old[1] + 2 - ie == ielen)
358 			break;
359 
360 		tmp_old += tmp_old[1] + 2;
361 	}
362 
363 	/* go through subelement again to check if there is any ie not
364 	 * copied to new ie, skip ssid, capability, bssid-index ie
365 	 */
366 	tmp_new = sub_copy;
367 	while (tmp_new + tmp_new[1] + 2 - sub_copy <= subie_len) {
368 		if (!(tmp_new[0] == WLAN_EID_NON_TX_BSSID_CAP ||
369 		      tmp_new[0] == WLAN_EID_SSID)) {
370 			memcpy(pos, tmp_new, tmp_new[1] + 2);
371 			pos += tmp_new[1] + 2;
372 		}
373 		if (tmp_new + tmp_new[1] + 2 - sub_copy == subie_len)
374 			break;
375 		tmp_new += tmp_new[1] + 2;
376 	}
377 
378 	kfree(sub_copy);
379 	return pos - new_ie;
380 }
381 
382 static bool is_bss(struct cfg80211_bss *a, const u8 *bssid,
383 		   const u8 *ssid, size_t ssid_len)
384 {
385 	const struct cfg80211_bss_ies *ies;
386 	const u8 *ssidie;
387 
388 	if (bssid && !ether_addr_equal(a->bssid, bssid))
389 		return false;
390 
391 	if (!ssid)
392 		return true;
393 
394 	ies = rcu_access_pointer(a->ies);
395 	if (!ies)
396 		return false;
397 	ssidie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len);
398 	if (!ssidie)
399 		return false;
400 	if (ssidie[1] != ssid_len)
401 		return false;
402 	return memcmp(ssidie + 2, ssid, ssid_len) == 0;
403 }
404 
405 static int
406 cfg80211_add_nontrans_list(struct cfg80211_bss *trans_bss,
407 			   struct cfg80211_bss *nontrans_bss)
408 {
409 	const u8 *ssid;
410 	size_t ssid_len;
411 	struct cfg80211_bss *bss = NULL;
412 
413 	rcu_read_lock();
414 	ssid = ieee80211_bss_get_ie(nontrans_bss, WLAN_EID_SSID);
415 	if (!ssid) {
416 		rcu_read_unlock();
417 		return -EINVAL;
418 	}
419 	ssid_len = ssid[1];
420 	ssid = ssid + 2;
421 	rcu_read_unlock();
422 
423 	/* check if nontrans_bss is in the list */
424 	list_for_each_entry(bss, &trans_bss->nontrans_list, nontrans_list) {
425 		if (is_bss(bss, nontrans_bss->bssid, ssid, ssid_len))
426 			return 0;
427 	}
428 
429 	/* add to the list */
430 	list_add_tail(&nontrans_bss->nontrans_list, &trans_bss->nontrans_list);
431 	return 0;
432 }
433 
434 static void __cfg80211_bss_expire(struct cfg80211_registered_device *rdev,
435 				  unsigned long expire_time)
436 {
437 	struct cfg80211_internal_bss *bss, *tmp;
438 	bool expired = false;
439 
440 	lockdep_assert_held(&rdev->bss_lock);
441 
442 	list_for_each_entry_safe(bss, tmp, &rdev->bss_list, list) {
443 		if (atomic_read(&bss->hold))
444 			continue;
445 		if (!time_after(expire_time, bss->ts))
446 			continue;
447 
448 		if (__cfg80211_unlink_bss(rdev, bss))
449 			expired = true;
450 	}
451 
452 	if (expired)
453 		rdev->bss_generation++;
454 }
455 
456 static bool cfg80211_bss_expire_oldest(struct cfg80211_registered_device *rdev)
457 {
458 	struct cfg80211_internal_bss *bss, *oldest = NULL;
459 	bool ret;
460 
461 	lockdep_assert_held(&rdev->bss_lock);
462 
463 	list_for_each_entry(bss, &rdev->bss_list, list) {
464 		if (atomic_read(&bss->hold))
465 			continue;
466 
467 		if (!list_empty(&bss->hidden_list) &&
468 		    !bss->pub.hidden_beacon_bss)
469 			continue;
470 
471 		if (oldest && time_before(oldest->ts, bss->ts))
472 			continue;
473 		oldest = bss;
474 	}
475 
476 	if (WARN_ON(!oldest))
477 		return false;
478 
479 	/*
480 	 * The callers make sure to increase rdev->bss_generation if anything
481 	 * gets removed (and a new entry added), so there's no need to also do
482 	 * it here.
483 	 */
484 
485 	ret = __cfg80211_unlink_bss(rdev, oldest);
486 	WARN_ON(!ret);
487 	return ret;
488 }
489 
490 static u8 cfg80211_parse_bss_param(u8 data,
491 				   struct cfg80211_colocated_ap *coloc_ap)
492 {
493 	coloc_ap->oct_recommended =
494 		u8_get_bits(data, IEEE80211_RNR_TBTT_PARAMS_OCT_RECOMMENDED);
495 	coloc_ap->same_ssid =
496 		u8_get_bits(data, IEEE80211_RNR_TBTT_PARAMS_SAME_SSID);
497 	coloc_ap->multi_bss =
498 		u8_get_bits(data, IEEE80211_RNR_TBTT_PARAMS_MULTI_BSSID);
499 	coloc_ap->transmitted_bssid =
500 		u8_get_bits(data, IEEE80211_RNR_TBTT_PARAMS_TRANSMITTED_BSSID);
501 	coloc_ap->unsolicited_probe =
502 		u8_get_bits(data, IEEE80211_RNR_TBTT_PARAMS_PROBE_ACTIVE);
503 	coloc_ap->colocated_ess =
504 		u8_get_bits(data, IEEE80211_RNR_TBTT_PARAMS_COLOC_ESS);
505 
506 	return u8_get_bits(data, IEEE80211_RNR_TBTT_PARAMS_COLOC_AP);
507 }
508 
509 static int cfg80211_calc_short_ssid(const struct cfg80211_bss_ies *ies,
510 				    const struct element **elem, u32 *s_ssid)
511 {
512 
513 	*elem = cfg80211_find_elem(WLAN_EID_SSID, ies->data, ies->len);
514 	if (!*elem || (*elem)->datalen > IEEE80211_MAX_SSID_LEN)
515 		return -EINVAL;
516 
517 	*s_ssid = ~crc32_le(~0, (*elem)->data, (*elem)->datalen);
518 	return 0;
519 }
520 
521 static void cfg80211_free_coloc_ap_list(struct list_head *coloc_ap_list)
522 {
523 	struct cfg80211_colocated_ap *ap, *tmp_ap;
524 
525 	list_for_each_entry_safe(ap, tmp_ap, coloc_ap_list, list) {
526 		list_del(&ap->list);
527 		kfree(ap);
528 	}
529 }
530 
531 static int cfg80211_parse_ap_info(struct cfg80211_colocated_ap *entry,
532 				  const u8 *pos, u8 length,
533 				  const struct element *ssid_elem,
534 				  int s_ssid_tmp)
535 {
536 	/* skip the TBTT offset */
537 	pos++;
538 
539 	memcpy(entry->bssid, pos, ETH_ALEN);
540 	pos += ETH_ALEN;
541 
542 	if (length == IEEE80211_TBTT_INFO_OFFSET_BSSID_SSSID_BSS_PARAM) {
543 		memcpy(&entry->short_ssid, pos,
544 		       sizeof(entry->short_ssid));
545 		entry->short_ssid_valid = true;
546 		pos += 4;
547 	}
548 
549 	/* skip non colocated APs */
550 	if (!cfg80211_parse_bss_param(*pos, entry))
551 		return -EINVAL;
552 	pos++;
553 
554 	if (length == IEEE80211_TBTT_INFO_OFFSET_BSSID_BSS_PARAM) {
555 		/*
556 		 * no information about the short ssid. Consider the entry valid
557 		 * for now. It would later be dropped in case there are explicit
558 		 * SSIDs that need to be matched
559 		 */
560 		if (!entry->same_ssid)
561 			return 0;
562 	}
563 
564 	if (entry->same_ssid) {
565 		entry->short_ssid = s_ssid_tmp;
566 		entry->short_ssid_valid = true;
567 
568 		/*
569 		 * This is safe because we validate datalen in
570 		 * cfg80211_parse_colocated_ap(), before calling this
571 		 * function.
572 		 */
573 		memcpy(&entry->ssid, &ssid_elem->data,
574 		       ssid_elem->datalen);
575 		entry->ssid_len = ssid_elem->datalen;
576 	}
577 	return 0;
578 }
579 
580 static int cfg80211_parse_colocated_ap(const struct cfg80211_bss_ies *ies,
581 				       struct list_head *list)
582 {
583 	struct ieee80211_neighbor_ap_info *ap_info;
584 	const struct element *elem, *ssid_elem;
585 	const u8 *pos, *end;
586 	u32 s_ssid_tmp;
587 	int n_coloc = 0, ret;
588 	LIST_HEAD(ap_list);
589 
590 	elem = cfg80211_find_elem(WLAN_EID_REDUCED_NEIGHBOR_REPORT, ies->data,
591 				  ies->len);
592 	if (!elem)
593 		return 0;
594 
595 	pos = elem->data;
596 	end = pos + elem->datalen;
597 
598 	ret = cfg80211_calc_short_ssid(ies, &ssid_elem, &s_ssid_tmp);
599 	if (ret)
600 		return ret;
601 
602 	/* RNR IE may contain more than one NEIGHBOR_AP_INFO */
603 	while (pos + sizeof(*ap_info) <= end) {
604 		enum nl80211_band band;
605 		int freq;
606 		u8 length, i, count;
607 
608 		ap_info = (void *)pos;
609 		count = u8_get_bits(ap_info->tbtt_info_hdr,
610 				    IEEE80211_AP_INFO_TBTT_HDR_COUNT) + 1;
611 		length = ap_info->tbtt_info_len;
612 
613 		pos += sizeof(*ap_info);
614 
615 		if (!ieee80211_operating_class_to_band(ap_info->op_class,
616 						       &band))
617 			break;
618 
619 		freq = ieee80211_channel_to_frequency(ap_info->channel, band);
620 
621 		if (end - pos < count * ap_info->tbtt_info_len)
622 			break;
623 
624 		/*
625 		 * TBTT info must include bss param + BSSID +
626 		 * (short SSID or same_ssid bit to be set).
627 		 * ignore other options, and move to the
628 		 * next AP info
629 		 */
630 		if (band != NL80211_BAND_6GHZ ||
631 		    (length != IEEE80211_TBTT_INFO_OFFSET_BSSID_BSS_PARAM &&
632 		     length < IEEE80211_TBTT_INFO_OFFSET_BSSID_SSSID_BSS_PARAM)) {
633 			pos += count * ap_info->tbtt_info_len;
634 			continue;
635 		}
636 
637 		for (i = 0; i < count; i++) {
638 			struct cfg80211_colocated_ap *entry;
639 
640 			entry = kzalloc(sizeof(*entry) + IEEE80211_MAX_SSID_LEN,
641 					GFP_ATOMIC);
642 
643 			if (!entry)
644 				break;
645 
646 			entry->center_freq = freq;
647 
648 			if (!cfg80211_parse_ap_info(entry, pos, length,
649 						    ssid_elem, s_ssid_tmp)) {
650 				n_coloc++;
651 				list_add_tail(&entry->list, &ap_list);
652 			} else {
653 				kfree(entry);
654 			}
655 
656 			pos += ap_info->tbtt_info_len;
657 		}
658 	}
659 
660 	if (pos != end) {
661 		cfg80211_free_coloc_ap_list(&ap_list);
662 		return 0;
663 	}
664 
665 	list_splice_tail(&ap_list, list);
666 	return n_coloc;
667 }
668 
669 static  void cfg80211_scan_req_add_chan(struct cfg80211_scan_request *request,
670 					struct ieee80211_channel *chan,
671 					bool add_to_6ghz)
672 {
673 	int i;
674 	u32 n_channels = request->n_channels;
675 	struct cfg80211_scan_6ghz_params *params =
676 		&request->scan_6ghz_params[request->n_6ghz_params];
677 
678 	for (i = 0; i < n_channels; i++) {
679 		if (request->channels[i] == chan) {
680 			if (add_to_6ghz)
681 				params->channel_idx = i;
682 			return;
683 		}
684 	}
685 
686 	request->channels[n_channels] = chan;
687 	if (add_to_6ghz)
688 		request->scan_6ghz_params[request->n_6ghz_params].channel_idx =
689 			n_channels;
690 
691 	request->n_channels++;
692 }
693 
694 static bool cfg80211_find_ssid_match(struct cfg80211_colocated_ap *ap,
695 				     struct cfg80211_scan_request *request)
696 {
697 	int i;
698 	u32 s_ssid;
699 
700 	for (i = 0; i < request->n_ssids; i++) {
701 		/* wildcard ssid in the scan request */
702 		if (!request->ssids[i].ssid_len)
703 			return true;
704 
705 		if (ap->ssid_len &&
706 		    ap->ssid_len == request->ssids[i].ssid_len) {
707 			if (!memcmp(request->ssids[i].ssid, ap->ssid,
708 				    ap->ssid_len))
709 				return true;
710 		} else if (ap->short_ssid_valid) {
711 			s_ssid = ~crc32_le(~0, request->ssids[i].ssid,
712 					   request->ssids[i].ssid_len);
713 
714 			if (ap->short_ssid == s_ssid)
715 				return true;
716 		}
717 	}
718 
719 	return false;
720 }
721 
722 static int cfg80211_scan_6ghz(struct cfg80211_registered_device *rdev)
723 {
724 	u8 i;
725 	struct cfg80211_colocated_ap *ap;
726 	int n_channels, count = 0, err;
727 	struct cfg80211_scan_request *request, *rdev_req = rdev->scan_req;
728 	LIST_HEAD(coloc_ap_list);
729 	bool need_scan_psc = true;
730 	const struct ieee80211_sband_iftype_data *iftd;
731 
732 	rdev_req->scan_6ghz = true;
733 
734 	if (!rdev->wiphy.bands[NL80211_BAND_6GHZ])
735 		return -EOPNOTSUPP;
736 
737 	iftd = ieee80211_get_sband_iftype_data(rdev->wiphy.bands[NL80211_BAND_6GHZ],
738 					       rdev_req->wdev->iftype);
739 	if (!iftd || !iftd->he_cap.has_he)
740 		return -EOPNOTSUPP;
741 
742 	n_channels = rdev->wiphy.bands[NL80211_BAND_6GHZ]->n_channels;
743 
744 	if (rdev_req->flags & NL80211_SCAN_FLAG_COLOCATED_6GHZ) {
745 		struct cfg80211_internal_bss *intbss;
746 
747 		spin_lock_bh(&rdev->bss_lock);
748 		list_for_each_entry(intbss, &rdev->bss_list, list) {
749 			struct cfg80211_bss *res = &intbss->pub;
750 			const struct cfg80211_bss_ies *ies;
751 
752 			ies = rcu_access_pointer(res->ies);
753 			count += cfg80211_parse_colocated_ap(ies,
754 							     &coloc_ap_list);
755 		}
756 		spin_unlock_bh(&rdev->bss_lock);
757 	}
758 
759 	request = kzalloc(struct_size(request, channels, n_channels) +
760 			  sizeof(*request->scan_6ghz_params) * count,
761 			  GFP_KERNEL);
762 	if (!request) {
763 		cfg80211_free_coloc_ap_list(&coloc_ap_list);
764 		return -ENOMEM;
765 	}
766 
767 	*request = *rdev_req;
768 	request->n_channels = 0;
769 	request->scan_6ghz_params =
770 		(void *)&request->channels[n_channels];
771 
772 	/*
773 	 * PSC channels should not be scanned in case of direct scan with 1 SSID
774 	 * and at least one of the reported co-located APs with same SSID
775 	 * indicating that all APs in the same ESS are co-located
776 	 */
777 	if (count && request->n_ssids == 1 && request->ssids[0].ssid_len) {
778 		list_for_each_entry(ap, &coloc_ap_list, list) {
779 			if (ap->colocated_ess &&
780 			    cfg80211_find_ssid_match(ap, request)) {
781 				need_scan_psc = false;
782 				break;
783 			}
784 		}
785 	}
786 
787 	/*
788 	 * add to the scan request the channels that need to be scanned
789 	 * regardless of the collocated APs (PSC channels or all channels
790 	 * in case that NL80211_SCAN_FLAG_COLOCATED_6GHZ is not set)
791 	 */
792 	for (i = 0; i < rdev_req->n_channels; i++) {
793 		if (rdev_req->channels[i]->band == NL80211_BAND_6GHZ &&
794 		    ((need_scan_psc &&
795 		      cfg80211_channel_is_psc(rdev_req->channels[i])) ||
796 		     !(rdev_req->flags & NL80211_SCAN_FLAG_COLOCATED_6GHZ))) {
797 			cfg80211_scan_req_add_chan(request,
798 						   rdev_req->channels[i],
799 						   false);
800 		}
801 	}
802 
803 	if (!(rdev_req->flags & NL80211_SCAN_FLAG_COLOCATED_6GHZ))
804 		goto skip;
805 
806 	list_for_each_entry(ap, &coloc_ap_list, list) {
807 		bool found = false;
808 		struct cfg80211_scan_6ghz_params *scan_6ghz_params =
809 			&request->scan_6ghz_params[request->n_6ghz_params];
810 		struct ieee80211_channel *chan =
811 			ieee80211_get_channel(&rdev->wiphy, ap->center_freq);
812 
813 		if (!chan || chan->flags & IEEE80211_CHAN_DISABLED)
814 			continue;
815 
816 		for (i = 0; i < rdev_req->n_channels; i++) {
817 			if (rdev_req->channels[i] == chan)
818 				found = true;
819 		}
820 
821 		if (!found)
822 			continue;
823 
824 		if (request->n_ssids > 0 &&
825 		    !cfg80211_find_ssid_match(ap, request))
826 			continue;
827 
828 		cfg80211_scan_req_add_chan(request, chan, true);
829 		memcpy(scan_6ghz_params->bssid, ap->bssid, ETH_ALEN);
830 		scan_6ghz_params->short_ssid = ap->short_ssid;
831 		scan_6ghz_params->short_ssid_valid = ap->short_ssid_valid;
832 		scan_6ghz_params->unsolicited_probe = ap->unsolicited_probe;
833 
834 		/*
835 		 * If a PSC channel is added to the scan and 'need_scan_psc' is
836 		 * set to false, then all the APs that the scan logic is
837 		 * interested with on the channel are collocated and thus there
838 		 * is no need to perform the initial PSC channel listen.
839 		 */
840 		if (cfg80211_channel_is_psc(chan) && !need_scan_psc)
841 			scan_6ghz_params->psc_no_listen = true;
842 
843 		request->n_6ghz_params++;
844 	}
845 
846 skip:
847 	cfg80211_free_coloc_ap_list(&coloc_ap_list);
848 
849 	if (request->n_channels) {
850 		struct cfg80211_scan_request *old = rdev->int_scan_req;
851 
852 		rdev->int_scan_req = request;
853 
854 		/*
855 		 * If this scan follows a previous scan, save the scan start
856 		 * info from the first part of the scan
857 		 */
858 		if (old)
859 			rdev->int_scan_req->info = old->info;
860 
861 		err = rdev_scan(rdev, request);
862 		if (err) {
863 			rdev->int_scan_req = old;
864 			kfree(request);
865 		} else {
866 			kfree(old);
867 		}
868 
869 		return err;
870 	}
871 
872 	kfree(request);
873 	return -EINVAL;
874 }
875 
876 int cfg80211_scan(struct cfg80211_registered_device *rdev)
877 {
878 	struct cfg80211_scan_request *request;
879 	struct cfg80211_scan_request *rdev_req = rdev->scan_req;
880 	u32 n_channels = 0, idx, i;
881 
882 	if (!(rdev->wiphy.flags & WIPHY_FLAG_SPLIT_SCAN_6GHZ))
883 		return rdev_scan(rdev, rdev_req);
884 
885 	for (i = 0; i < rdev_req->n_channels; i++) {
886 		if (rdev_req->channels[i]->band != NL80211_BAND_6GHZ)
887 			n_channels++;
888 	}
889 
890 	if (!n_channels)
891 		return cfg80211_scan_6ghz(rdev);
892 
893 	request = kzalloc(struct_size(request, channels, n_channels),
894 			  GFP_KERNEL);
895 	if (!request)
896 		return -ENOMEM;
897 
898 	*request = *rdev_req;
899 	request->n_channels = n_channels;
900 
901 	for (i = idx = 0; i < rdev_req->n_channels; i++) {
902 		if (rdev_req->channels[i]->band != NL80211_BAND_6GHZ)
903 			request->channels[idx++] = rdev_req->channels[i];
904 	}
905 
906 	rdev_req->scan_6ghz = false;
907 	rdev->int_scan_req = request;
908 	return rdev_scan(rdev, request);
909 }
910 
911 void ___cfg80211_scan_done(struct cfg80211_registered_device *rdev,
912 			   bool send_message)
913 {
914 	struct cfg80211_scan_request *request, *rdev_req;
915 	struct wireless_dev *wdev;
916 	struct sk_buff *msg;
917 #ifdef CONFIG_CFG80211_WEXT
918 	union iwreq_data wrqu;
919 #endif
920 
921 	lockdep_assert_held(&rdev->wiphy.mtx);
922 
923 	if (rdev->scan_msg) {
924 		nl80211_send_scan_msg(rdev, rdev->scan_msg);
925 		rdev->scan_msg = NULL;
926 		return;
927 	}
928 
929 	rdev_req = rdev->scan_req;
930 	if (!rdev_req)
931 		return;
932 
933 	wdev = rdev_req->wdev;
934 	request = rdev->int_scan_req ? rdev->int_scan_req : rdev_req;
935 
936 	if (wdev_running(wdev) &&
937 	    (rdev->wiphy.flags & WIPHY_FLAG_SPLIT_SCAN_6GHZ) &&
938 	    !rdev_req->scan_6ghz && !request->info.aborted &&
939 	    !cfg80211_scan_6ghz(rdev))
940 		return;
941 
942 	/*
943 	 * This must be before sending the other events!
944 	 * Otherwise, wpa_supplicant gets completely confused with
945 	 * wext events.
946 	 */
947 	if (wdev->netdev)
948 		cfg80211_sme_scan_done(wdev->netdev);
949 
950 	if (!request->info.aborted &&
951 	    request->flags & NL80211_SCAN_FLAG_FLUSH) {
952 		/* flush entries from previous scans */
953 		spin_lock_bh(&rdev->bss_lock);
954 		__cfg80211_bss_expire(rdev, request->scan_start);
955 		spin_unlock_bh(&rdev->bss_lock);
956 	}
957 
958 	msg = nl80211_build_scan_msg(rdev, wdev, request->info.aborted);
959 
960 #ifdef CONFIG_CFG80211_WEXT
961 	if (wdev->netdev && !request->info.aborted) {
962 		memset(&wrqu, 0, sizeof(wrqu));
963 
964 		wireless_send_event(wdev->netdev, SIOCGIWSCAN, &wrqu, NULL);
965 	}
966 #endif
967 
968 	if (wdev->netdev)
969 		dev_put(wdev->netdev);
970 
971 	kfree(rdev->int_scan_req);
972 	rdev->int_scan_req = NULL;
973 
974 	kfree(rdev->scan_req);
975 	rdev->scan_req = NULL;
976 
977 	if (!send_message)
978 		rdev->scan_msg = msg;
979 	else
980 		nl80211_send_scan_msg(rdev, msg);
981 }
982 
983 void __cfg80211_scan_done(struct work_struct *wk)
984 {
985 	struct cfg80211_registered_device *rdev;
986 
987 	rdev = container_of(wk, struct cfg80211_registered_device,
988 			    scan_done_wk);
989 
990 	wiphy_lock(&rdev->wiphy);
991 	___cfg80211_scan_done(rdev, true);
992 	wiphy_unlock(&rdev->wiphy);
993 }
994 
995 void cfg80211_scan_done(struct cfg80211_scan_request *request,
996 			struct cfg80211_scan_info *info)
997 {
998 	struct cfg80211_scan_info old_info = request->info;
999 
1000 	trace_cfg80211_scan_done(request, info);
1001 	WARN_ON(request != wiphy_to_rdev(request->wiphy)->scan_req &&
1002 		request != wiphy_to_rdev(request->wiphy)->int_scan_req);
1003 
1004 	request->info = *info;
1005 
1006 	/*
1007 	 * In case the scan is split, the scan_start_tsf and tsf_bssid should
1008 	 * be of the first part. In such a case old_info.scan_start_tsf should
1009 	 * be non zero.
1010 	 */
1011 	if (request->scan_6ghz && old_info.scan_start_tsf) {
1012 		request->info.scan_start_tsf = old_info.scan_start_tsf;
1013 		memcpy(request->info.tsf_bssid, old_info.tsf_bssid,
1014 		       sizeof(request->info.tsf_bssid));
1015 	}
1016 
1017 	request->notified = true;
1018 	queue_work(cfg80211_wq, &wiphy_to_rdev(request->wiphy)->scan_done_wk);
1019 }
1020 EXPORT_SYMBOL(cfg80211_scan_done);
1021 
1022 void cfg80211_add_sched_scan_req(struct cfg80211_registered_device *rdev,
1023 				 struct cfg80211_sched_scan_request *req)
1024 {
1025 	lockdep_assert_held(&rdev->wiphy.mtx);
1026 
1027 	list_add_rcu(&req->list, &rdev->sched_scan_req_list);
1028 }
1029 
1030 static void cfg80211_del_sched_scan_req(struct cfg80211_registered_device *rdev,
1031 					struct cfg80211_sched_scan_request *req)
1032 {
1033 	lockdep_assert_held(&rdev->wiphy.mtx);
1034 
1035 	list_del_rcu(&req->list);
1036 	kfree_rcu(req, rcu_head);
1037 }
1038 
1039 static struct cfg80211_sched_scan_request *
1040 cfg80211_find_sched_scan_req(struct cfg80211_registered_device *rdev, u64 reqid)
1041 {
1042 	struct cfg80211_sched_scan_request *pos;
1043 
1044 	list_for_each_entry_rcu(pos, &rdev->sched_scan_req_list, list,
1045 				lockdep_is_held(&rdev->wiphy.mtx)) {
1046 		if (pos->reqid == reqid)
1047 			return pos;
1048 	}
1049 	return NULL;
1050 }
1051 
1052 /*
1053  * Determines if a scheduled scan request can be handled. When a legacy
1054  * scheduled scan is running no other scheduled scan is allowed regardless
1055  * whether the request is for legacy or multi-support scan. When a multi-support
1056  * scheduled scan is running a request for legacy scan is not allowed. In this
1057  * case a request for multi-support scan can be handled if resources are
1058  * available, ie. struct wiphy::max_sched_scan_reqs limit is not yet reached.
1059  */
1060 int cfg80211_sched_scan_req_possible(struct cfg80211_registered_device *rdev,
1061 				     bool want_multi)
1062 {
1063 	struct cfg80211_sched_scan_request *pos;
1064 	int i = 0;
1065 
1066 	list_for_each_entry(pos, &rdev->sched_scan_req_list, list) {
1067 		/* request id zero means legacy in progress */
1068 		if (!i && !pos->reqid)
1069 			return -EINPROGRESS;
1070 		i++;
1071 	}
1072 
1073 	if (i) {
1074 		/* no legacy allowed when multi request(s) are active */
1075 		if (!want_multi)
1076 			return -EINPROGRESS;
1077 
1078 		/* resource limit reached */
1079 		if (i == rdev->wiphy.max_sched_scan_reqs)
1080 			return -ENOSPC;
1081 	}
1082 	return 0;
1083 }
1084 
1085 void cfg80211_sched_scan_results_wk(struct work_struct *work)
1086 {
1087 	struct cfg80211_registered_device *rdev;
1088 	struct cfg80211_sched_scan_request *req, *tmp;
1089 
1090 	rdev = container_of(work, struct cfg80211_registered_device,
1091 			   sched_scan_res_wk);
1092 
1093 	wiphy_lock(&rdev->wiphy);
1094 	list_for_each_entry_safe(req, tmp, &rdev->sched_scan_req_list, list) {
1095 		if (req->report_results) {
1096 			req->report_results = false;
1097 			if (req->flags & NL80211_SCAN_FLAG_FLUSH) {
1098 				/* flush entries from previous scans */
1099 				spin_lock_bh(&rdev->bss_lock);
1100 				__cfg80211_bss_expire(rdev, req->scan_start);
1101 				spin_unlock_bh(&rdev->bss_lock);
1102 				req->scan_start = jiffies;
1103 			}
1104 			nl80211_send_sched_scan(req,
1105 						NL80211_CMD_SCHED_SCAN_RESULTS);
1106 		}
1107 	}
1108 	wiphy_unlock(&rdev->wiphy);
1109 }
1110 
1111 void cfg80211_sched_scan_results(struct wiphy *wiphy, u64 reqid)
1112 {
1113 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1114 	struct cfg80211_sched_scan_request *request;
1115 
1116 	trace_cfg80211_sched_scan_results(wiphy, reqid);
1117 	/* ignore if we're not scanning */
1118 
1119 	rcu_read_lock();
1120 	request = cfg80211_find_sched_scan_req(rdev, reqid);
1121 	if (request) {
1122 		request->report_results = true;
1123 		queue_work(cfg80211_wq, &rdev->sched_scan_res_wk);
1124 	}
1125 	rcu_read_unlock();
1126 }
1127 EXPORT_SYMBOL(cfg80211_sched_scan_results);
1128 
1129 void cfg80211_sched_scan_stopped_locked(struct wiphy *wiphy, u64 reqid)
1130 {
1131 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1132 
1133 	lockdep_assert_held(&wiphy->mtx);
1134 
1135 	trace_cfg80211_sched_scan_stopped(wiphy, reqid);
1136 
1137 	__cfg80211_stop_sched_scan(rdev, reqid, true);
1138 }
1139 EXPORT_SYMBOL(cfg80211_sched_scan_stopped_locked);
1140 
1141 void cfg80211_sched_scan_stopped(struct wiphy *wiphy, u64 reqid)
1142 {
1143 	wiphy_lock(wiphy);
1144 	cfg80211_sched_scan_stopped_locked(wiphy, reqid);
1145 	wiphy_unlock(wiphy);
1146 }
1147 EXPORT_SYMBOL(cfg80211_sched_scan_stopped);
1148 
1149 int cfg80211_stop_sched_scan_req(struct cfg80211_registered_device *rdev,
1150 				 struct cfg80211_sched_scan_request *req,
1151 				 bool driver_initiated)
1152 {
1153 	lockdep_assert_held(&rdev->wiphy.mtx);
1154 
1155 	if (!driver_initiated) {
1156 		int err = rdev_sched_scan_stop(rdev, req->dev, req->reqid);
1157 		if (err)
1158 			return err;
1159 	}
1160 
1161 	nl80211_send_sched_scan(req, NL80211_CMD_SCHED_SCAN_STOPPED);
1162 
1163 	cfg80211_del_sched_scan_req(rdev, req);
1164 
1165 	return 0;
1166 }
1167 
1168 int __cfg80211_stop_sched_scan(struct cfg80211_registered_device *rdev,
1169 			       u64 reqid, bool driver_initiated)
1170 {
1171 	struct cfg80211_sched_scan_request *sched_scan_req;
1172 
1173 	lockdep_assert_held(&rdev->wiphy.mtx);
1174 
1175 	sched_scan_req = cfg80211_find_sched_scan_req(rdev, reqid);
1176 	if (!sched_scan_req)
1177 		return -ENOENT;
1178 
1179 	return cfg80211_stop_sched_scan_req(rdev, sched_scan_req,
1180 					    driver_initiated);
1181 }
1182 
1183 void cfg80211_bss_age(struct cfg80211_registered_device *rdev,
1184                       unsigned long age_secs)
1185 {
1186 	struct cfg80211_internal_bss *bss;
1187 	unsigned long age_jiffies = msecs_to_jiffies(age_secs * MSEC_PER_SEC);
1188 
1189 	spin_lock_bh(&rdev->bss_lock);
1190 	list_for_each_entry(bss, &rdev->bss_list, list)
1191 		bss->ts -= age_jiffies;
1192 	spin_unlock_bh(&rdev->bss_lock);
1193 }
1194 
1195 void cfg80211_bss_expire(struct cfg80211_registered_device *rdev)
1196 {
1197 	__cfg80211_bss_expire(rdev, jiffies - IEEE80211_SCAN_RESULT_EXPIRE);
1198 }
1199 
1200 void cfg80211_bss_flush(struct wiphy *wiphy)
1201 {
1202 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1203 
1204 	spin_lock_bh(&rdev->bss_lock);
1205 	__cfg80211_bss_expire(rdev, jiffies);
1206 	spin_unlock_bh(&rdev->bss_lock);
1207 }
1208 EXPORT_SYMBOL(cfg80211_bss_flush);
1209 
1210 const struct element *
1211 cfg80211_find_elem_match(u8 eid, const u8 *ies, unsigned int len,
1212 			 const u8 *match, unsigned int match_len,
1213 			 unsigned int match_offset)
1214 {
1215 	const struct element *elem;
1216 
1217 	for_each_element_id(elem, eid, ies, len) {
1218 		if (elem->datalen >= match_offset + match_len &&
1219 		    !memcmp(elem->data + match_offset, match, match_len))
1220 			return elem;
1221 	}
1222 
1223 	return NULL;
1224 }
1225 EXPORT_SYMBOL(cfg80211_find_elem_match);
1226 
1227 const struct element *cfg80211_find_vendor_elem(unsigned int oui, int oui_type,
1228 						const u8 *ies,
1229 						unsigned int len)
1230 {
1231 	const struct element *elem;
1232 	u8 match[] = { oui >> 16, oui >> 8, oui, oui_type };
1233 	int match_len = (oui_type < 0) ? 3 : sizeof(match);
1234 
1235 	if (WARN_ON(oui_type > 0xff))
1236 		return NULL;
1237 
1238 	elem = cfg80211_find_elem_match(WLAN_EID_VENDOR_SPECIFIC, ies, len,
1239 					match, match_len, 0);
1240 
1241 	if (!elem || elem->datalen < 4)
1242 		return NULL;
1243 
1244 	return elem;
1245 }
1246 EXPORT_SYMBOL(cfg80211_find_vendor_elem);
1247 
1248 /**
1249  * enum bss_compare_mode - BSS compare mode
1250  * @BSS_CMP_REGULAR: regular compare mode (for insertion and normal find)
1251  * @BSS_CMP_HIDE_ZLEN: find hidden SSID with zero-length mode
1252  * @BSS_CMP_HIDE_NUL: find hidden SSID with NUL-ed out mode
1253  */
1254 enum bss_compare_mode {
1255 	BSS_CMP_REGULAR,
1256 	BSS_CMP_HIDE_ZLEN,
1257 	BSS_CMP_HIDE_NUL,
1258 };
1259 
1260 static int cmp_bss(struct cfg80211_bss *a,
1261 		   struct cfg80211_bss *b,
1262 		   enum bss_compare_mode mode)
1263 {
1264 	const struct cfg80211_bss_ies *a_ies, *b_ies;
1265 	const u8 *ie1 = NULL;
1266 	const u8 *ie2 = NULL;
1267 	int i, r;
1268 
1269 	if (a->channel != b->channel)
1270 		return b->channel->center_freq - a->channel->center_freq;
1271 
1272 	a_ies = rcu_access_pointer(a->ies);
1273 	if (!a_ies)
1274 		return -1;
1275 	b_ies = rcu_access_pointer(b->ies);
1276 	if (!b_ies)
1277 		return 1;
1278 
1279 	if (WLAN_CAPABILITY_IS_STA_BSS(a->capability))
1280 		ie1 = cfg80211_find_ie(WLAN_EID_MESH_ID,
1281 				       a_ies->data, a_ies->len);
1282 	if (WLAN_CAPABILITY_IS_STA_BSS(b->capability))
1283 		ie2 = cfg80211_find_ie(WLAN_EID_MESH_ID,
1284 				       b_ies->data, b_ies->len);
1285 	if (ie1 && ie2) {
1286 		int mesh_id_cmp;
1287 
1288 		if (ie1[1] == ie2[1])
1289 			mesh_id_cmp = memcmp(ie1 + 2, ie2 + 2, ie1[1]);
1290 		else
1291 			mesh_id_cmp = ie2[1] - ie1[1];
1292 
1293 		ie1 = cfg80211_find_ie(WLAN_EID_MESH_CONFIG,
1294 				       a_ies->data, a_ies->len);
1295 		ie2 = cfg80211_find_ie(WLAN_EID_MESH_CONFIG,
1296 				       b_ies->data, b_ies->len);
1297 		if (ie1 && ie2) {
1298 			if (mesh_id_cmp)
1299 				return mesh_id_cmp;
1300 			if (ie1[1] != ie2[1])
1301 				return ie2[1] - ie1[1];
1302 			return memcmp(ie1 + 2, ie2 + 2, ie1[1]);
1303 		}
1304 	}
1305 
1306 	r = memcmp(a->bssid, b->bssid, sizeof(a->bssid));
1307 	if (r)
1308 		return r;
1309 
1310 	ie1 = cfg80211_find_ie(WLAN_EID_SSID, a_ies->data, a_ies->len);
1311 	ie2 = cfg80211_find_ie(WLAN_EID_SSID, b_ies->data, b_ies->len);
1312 
1313 	if (!ie1 && !ie2)
1314 		return 0;
1315 
1316 	/*
1317 	 * Note that with "hide_ssid", the function returns a match if
1318 	 * the already-present BSS ("b") is a hidden SSID beacon for
1319 	 * the new BSS ("a").
1320 	 */
1321 
1322 	/* sort missing IE before (left of) present IE */
1323 	if (!ie1)
1324 		return -1;
1325 	if (!ie2)
1326 		return 1;
1327 
1328 	switch (mode) {
1329 	case BSS_CMP_HIDE_ZLEN:
1330 		/*
1331 		 * In ZLEN mode we assume the BSS entry we're
1332 		 * looking for has a zero-length SSID. So if
1333 		 * the one we're looking at right now has that,
1334 		 * return 0. Otherwise, return the difference
1335 		 * in length, but since we're looking for the
1336 		 * 0-length it's really equivalent to returning
1337 		 * the length of the one we're looking at.
1338 		 *
1339 		 * No content comparison is needed as we assume
1340 		 * the content length is zero.
1341 		 */
1342 		return ie2[1];
1343 	case BSS_CMP_REGULAR:
1344 	default:
1345 		/* sort by length first, then by contents */
1346 		if (ie1[1] != ie2[1])
1347 			return ie2[1] - ie1[1];
1348 		return memcmp(ie1 + 2, ie2 + 2, ie1[1]);
1349 	case BSS_CMP_HIDE_NUL:
1350 		if (ie1[1] != ie2[1])
1351 			return ie2[1] - ie1[1];
1352 		/* this is equivalent to memcmp(zeroes, ie2 + 2, len) */
1353 		for (i = 0; i < ie2[1]; i++)
1354 			if (ie2[i + 2])
1355 				return -1;
1356 		return 0;
1357 	}
1358 }
1359 
1360 static bool cfg80211_bss_type_match(u16 capability,
1361 				    enum nl80211_band band,
1362 				    enum ieee80211_bss_type bss_type)
1363 {
1364 	bool ret = true;
1365 	u16 mask, val;
1366 
1367 	if (bss_type == IEEE80211_BSS_TYPE_ANY)
1368 		return ret;
1369 
1370 	if (band == NL80211_BAND_60GHZ) {
1371 		mask = WLAN_CAPABILITY_DMG_TYPE_MASK;
1372 		switch (bss_type) {
1373 		case IEEE80211_BSS_TYPE_ESS:
1374 			val = WLAN_CAPABILITY_DMG_TYPE_AP;
1375 			break;
1376 		case IEEE80211_BSS_TYPE_PBSS:
1377 			val = WLAN_CAPABILITY_DMG_TYPE_PBSS;
1378 			break;
1379 		case IEEE80211_BSS_TYPE_IBSS:
1380 			val = WLAN_CAPABILITY_DMG_TYPE_IBSS;
1381 			break;
1382 		default:
1383 			return false;
1384 		}
1385 	} else {
1386 		mask = WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS;
1387 		switch (bss_type) {
1388 		case IEEE80211_BSS_TYPE_ESS:
1389 			val = WLAN_CAPABILITY_ESS;
1390 			break;
1391 		case IEEE80211_BSS_TYPE_IBSS:
1392 			val = WLAN_CAPABILITY_IBSS;
1393 			break;
1394 		case IEEE80211_BSS_TYPE_MBSS:
1395 			val = 0;
1396 			break;
1397 		default:
1398 			return false;
1399 		}
1400 	}
1401 
1402 	ret = ((capability & mask) == val);
1403 	return ret;
1404 }
1405 
1406 /* Returned bss is reference counted and must be cleaned up appropriately. */
1407 struct cfg80211_bss *cfg80211_get_bss(struct wiphy *wiphy,
1408 				      struct ieee80211_channel *channel,
1409 				      const u8 *bssid,
1410 				      const u8 *ssid, size_t ssid_len,
1411 				      enum ieee80211_bss_type bss_type,
1412 				      enum ieee80211_privacy privacy)
1413 {
1414 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1415 	struct cfg80211_internal_bss *bss, *res = NULL;
1416 	unsigned long now = jiffies;
1417 	int bss_privacy;
1418 
1419 	trace_cfg80211_get_bss(wiphy, channel, bssid, ssid, ssid_len, bss_type,
1420 			       privacy);
1421 
1422 	spin_lock_bh(&rdev->bss_lock);
1423 
1424 	list_for_each_entry(bss, &rdev->bss_list, list) {
1425 		if (!cfg80211_bss_type_match(bss->pub.capability,
1426 					     bss->pub.channel->band, bss_type))
1427 			continue;
1428 
1429 		bss_privacy = (bss->pub.capability & WLAN_CAPABILITY_PRIVACY);
1430 		if ((privacy == IEEE80211_PRIVACY_ON && !bss_privacy) ||
1431 		    (privacy == IEEE80211_PRIVACY_OFF && bss_privacy))
1432 			continue;
1433 		if (channel && bss->pub.channel != channel)
1434 			continue;
1435 		if (!is_valid_ether_addr(bss->pub.bssid))
1436 			continue;
1437 		/* Don't get expired BSS structs */
1438 		if (time_after(now, bss->ts + IEEE80211_SCAN_RESULT_EXPIRE) &&
1439 		    !atomic_read(&bss->hold))
1440 			continue;
1441 		if (is_bss(&bss->pub, bssid, ssid, ssid_len)) {
1442 			res = bss;
1443 			bss_ref_get(rdev, res);
1444 			break;
1445 		}
1446 	}
1447 
1448 	spin_unlock_bh(&rdev->bss_lock);
1449 	if (!res)
1450 		return NULL;
1451 	trace_cfg80211_return_bss(&res->pub);
1452 	return &res->pub;
1453 }
1454 EXPORT_SYMBOL(cfg80211_get_bss);
1455 
1456 static void rb_insert_bss(struct cfg80211_registered_device *rdev,
1457 			  struct cfg80211_internal_bss *bss)
1458 {
1459 	struct rb_node **p = &rdev->bss_tree.rb_node;
1460 	struct rb_node *parent = NULL;
1461 	struct cfg80211_internal_bss *tbss;
1462 	int cmp;
1463 
1464 	while (*p) {
1465 		parent = *p;
1466 		tbss = rb_entry(parent, struct cfg80211_internal_bss, rbn);
1467 
1468 		cmp = cmp_bss(&bss->pub, &tbss->pub, BSS_CMP_REGULAR);
1469 
1470 		if (WARN_ON(!cmp)) {
1471 			/* will sort of leak this BSS */
1472 			return;
1473 		}
1474 
1475 		if (cmp < 0)
1476 			p = &(*p)->rb_left;
1477 		else
1478 			p = &(*p)->rb_right;
1479 	}
1480 
1481 	rb_link_node(&bss->rbn, parent, p);
1482 	rb_insert_color(&bss->rbn, &rdev->bss_tree);
1483 }
1484 
1485 static struct cfg80211_internal_bss *
1486 rb_find_bss(struct cfg80211_registered_device *rdev,
1487 	    struct cfg80211_internal_bss *res,
1488 	    enum bss_compare_mode mode)
1489 {
1490 	struct rb_node *n = rdev->bss_tree.rb_node;
1491 	struct cfg80211_internal_bss *bss;
1492 	int r;
1493 
1494 	while (n) {
1495 		bss = rb_entry(n, struct cfg80211_internal_bss, rbn);
1496 		r = cmp_bss(&res->pub, &bss->pub, mode);
1497 
1498 		if (r == 0)
1499 			return bss;
1500 		else if (r < 0)
1501 			n = n->rb_left;
1502 		else
1503 			n = n->rb_right;
1504 	}
1505 
1506 	return NULL;
1507 }
1508 
1509 static bool cfg80211_combine_bsses(struct cfg80211_registered_device *rdev,
1510 				   struct cfg80211_internal_bss *new)
1511 {
1512 	const struct cfg80211_bss_ies *ies;
1513 	struct cfg80211_internal_bss *bss;
1514 	const u8 *ie;
1515 	int i, ssidlen;
1516 	u8 fold = 0;
1517 	u32 n_entries = 0;
1518 
1519 	ies = rcu_access_pointer(new->pub.beacon_ies);
1520 	if (WARN_ON(!ies))
1521 		return false;
1522 
1523 	ie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len);
1524 	if (!ie) {
1525 		/* nothing to do */
1526 		return true;
1527 	}
1528 
1529 	ssidlen = ie[1];
1530 	for (i = 0; i < ssidlen; i++)
1531 		fold |= ie[2 + i];
1532 
1533 	if (fold) {
1534 		/* not a hidden SSID */
1535 		return true;
1536 	}
1537 
1538 	/* This is the bad part ... */
1539 
1540 	list_for_each_entry(bss, &rdev->bss_list, list) {
1541 		/*
1542 		 * we're iterating all the entries anyway, so take the
1543 		 * opportunity to validate the list length accounting
1544 		 */
1545 		n_entries++;
1546 
1547 		if (!ether_addr_equal(bss->pub.bssid, new->pub.bssid))
1548 			continue;
1549 		if (bss->pub.channel != new->pub.channel)
1550 			continue;
1551 		if (bss->pub.scan_width != new->pub.scan_width)
1552 			continue;
1553 		if (rcu_access_pointer(bss->pub.beacon_ies))
1554 			continue;
1555 		ies = rcu_access_pointer(bss->pub.ies);
1556 		if (!ies)
1557 			continue;
1558 		ie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len);
1559 		if (!ie)
1560 			continue;
1561 		if (ssidlen && ie[1] != ssidlen)
1562 			continue;
1563 		if (WARN_ON_ONCE(bss->pub.hidden_beacon_bss))
1564 			continue;
1565 		if (WARN_ON_ONCE(!list_empty(&bss->hidden_list)))
1566 			list_del(&bss->hidden_list);
1567 		/* combine them */
1568 		list_add(&bss->hidden_list, &new->hidden_list);
1569 		bss->pub.hidden_beacon_bss = &new->pub;
1570 		new->refcount += bss->refcount;
1571 		rcu_assign_pointer(bss->pub.beacon_ies,
1572 				   new->pub.beacon_ies);
1573 	}
1574 
1575 	WARN_ONCE(n_entries != rdev->bss_entries,
1576 		  "rdev bss entries[%d]/list[len:%d] corruption\n",
1577 		  rdev->bss_entries, n_entries);
1578 
1579 	return true;
1580 }
1581 
1582 struct cfg80211_non_tx_bss {
1583 	struct cfg80211_bss *tx_bss;
1584 	u8 max_bssid_indicator;
1585 	u8 bssid_index;
1586 };
1587 
1588 static bool
1589 cfg80211_update_known_bss(struct cfg80211_registered_device *rdev,
1590 			  struct cfg80211_internal_bss *known,
1591 			  struct cfg80211_internal_bss *new,
1592 			  bool signal_valid)
1593 {
1594 	lockdep_assert_held(&rdev->bss_lock);
1595 
1596 	/* Update IEs */
1597 	if (rcu_access_pointer(new->pub.proberesp_ies)) {
1598 		const struct cfg80211_bss_ies *old;
1599 
1600 		old = rcu_access_pointer(known->pub.proberesp_ies);
1601 
1602 		rcu_assign_pointer(known->pub.proberesp_ies,
1603 				   new->pub.proberesp_ies);
1604 		/* Override possible earlier Beacon frame IEs */
1605 		rcu_assign_pointer(known->pub.ies,
1606 				   new->pub.proberesp_ies);
1607 		if (old)
1608 			kfree_rcu((struct cfg80211_bss_ies *)old, rcu_head);
1609 	} else if (rcu_access_pointer(new->pub.beacon_ies)) {
1610 		const struct cfg80211_bss_ies *old;
1611 		struct cfg80211_internal_bss *bss;
1612 
1613 		if (known->pub.hidden_beacon_bss &&
1614 		    !list_empty(&known->hidden_list)) {
1615 			const struct cfg80211_bss_ies *f;
1616 
1617 			/* The known BSS struct is one of the probe
1618 			 * response members of a group, but we're
1619 			 * receiving a beacon (beacon_ies in the new
1620 			 * bss is used). This can only mean that the
1621 			 * AP changed its beacon from not having an
1622 			 * SSID to showing it, which is confusing so
1623 			 * drop this information.
1624 			 */
1625 
1626 			f = rcu_access_pointer(new->pub.beacon_ies);
1627 			kfree_rcu((struct cfg80211_bss_ies *)f, rcu_head);
1628 			return false;
1629 		}
1630 
1631 		old = rcu_access_pointer(known->pub.beacon_ies);
1632 
1633 		rcu_assign_pointer(known->pub.beacon_ies, new->pub.beacon_ies);
1634 
1635 		/* Override IEs if they were from a beacon before */
1636 		if (old == rcu_access_pointer(known->pub.ies))
1637 			rcu_assign_pointer(known->pub.ies, new->pub.beacon_ies);
1638 
1639 		/* Assign beacon IEs to all sub entries */
1640 		list_for_each_entry(bss, &known->hidden_list, hidden_list) {
1641 			const struct cfg80211_bss_ies *ies;
1642 
1643 			ies = rcu_access_pointer(bss->pub.beacon_ies);
1644 			WARN_ON(ies != old);
1645 
1646 			rcu_assign_pointer(bss->pub.beacon_ies,
1647 					   new->pub.beacon_ies);
1648 		}
1649 
1650 		if (old)
1651 			kfree_rcu((struct cfg80211_bss_ies *)old, rcu_head);
1652 	}
1653 
1654 	known->pub.beacon_interval = new->pub.beacon_interval;
1655 
1656 	/* don't update the signal if beacon was heard on
1657 	 * adjacent channel.
1658 	 */
1659 	if (signal_valid)
1660 		known->pub.signal = new->pub.signal;
1661 	known->pub.capability = new->pub.capability;
1662 	known->ts = new->ts;
1663 	known->ts_boottime = new->ts_boottime;
1664 	known->parent_tsf = new->parent_tsf;
1665 	known->pub.chains = new->pub.chains;
1666 	memcpy(known->pub.chain_signal, new->pub.chain_signal,
1667 	       IEEE80211_MAX_CHAINS);
1668 	ether_addr_copy(known->parent_bssid, new->parent_bssid);
1669 	known->pub.max_bssid_indicator = new->pub.max_bssid_indicator;
1670 	known->pub.bssid_index = new->pub.bssid_index;
1671 
1672 	return true;
1673 }
1674 
1675 /* Returned bss is reference counted and must be cleaned up appropriately. */
1676 struct cfg80211_internal_bss *
1677 cfg80211_bss_update(struct cfg80211_registered_device *rdev,
1678 		    struct cfg80211_internal_bss *tmp,
1679 		    bool signal_valid, unsigned long ts)
1680 {
1681 	struct cfg80211_internal_bss *found = NULL;
1682 
1683 	if (WARN_ON(!tmp->pub.channel))
1684 		return NULL;
1685 
1686 	tmp->ts = ts;
1687 
1688 	spin_lock_bh(&rdev->bss_lock);
1689 
1690 	if (WARN_ON(!rcu_access_pointer(tmp->pub.ies))) {
1691 		spin_unlock_bh(&rdev->bss_lock);
1692 		return NULL;
1693 	}
1694 
1695 	found = rb_find_bss(rdev, tmp, BSS_CMP_REGULAR);
1696 
1697 	if (found) {
1698 		if (!cfg80211_update_known_bss(rdev, found, tmp, signal_valid))
1699 			goto drop;
1700 	} else {
1701 		struct cfg80211_internal_bss *new;
1702 		struct cfg80211_internal_bss *hidden;
1703 		struct cfg80211_bss_ies *ies;
1704 
1705 		/*
1706 		 * create a copy -- the "res" variable that is passed in
1707 		 * is allocated on the stack since it's not needed in the
1708 		 * more common case of an update
1709 		 */
1710 		new = kzalloc(sizeof(*new) + rdev->wiphy.bss_priv_size,
1711 			      GFP_ATOMIC);
1712 		if (!new) {
1713 			ies = (void *)rcu_dereference(tmp->pub.beacon_ies);
1714 			if (ies)
1715 				kfree_rcu(ies, rcu_head);
1716 			ies = (void *)rcu_dereference(tmp->pub.proberesp_ies);
1717 			if (ies)
1718 				kfree_rcu(ies, rcu_head);
1719 			goto drop;
1720 		}
1721 		memcpy(new, tmp, sizeof(*new));
1722 		new->refcount = 1;
1723 		INIT_LIST_HEAD(&new->hidden_list);
1724 		INIT_LIST_HEAD(&new->pub.nontrans_list);
1725 
1726 		if (rcu_access_pointer(tmp->pub.proberesp_ies)) {
1727 			hidden = rb_find_bss(rdev, tmp, BSS_CMP_HIDE_ZLEN);
1728 			if (!hidden)
1729 				hidden = rb_find_bss(rdev, tmp,
1730 						     BSS_CMP_HIDE_NUL);
1731 			if (hidden) {
1732 				new->pub.hidden_beacon_bss = &hidden->pub;
1733 				list_add(&new->hidden_list,
1734 					 &hidden->hidden_list);
1735 				hidden->refcount++;
1736 				rcu_assign_pointer(new->pub.beacon_ies,
1737 						   hidden->pub.beacon_ies);
1738 			}
1739 		} else {
1740 			/*
1741 			 * Ok so we found a beacon, and don't have an entry. If
1742 			 * it's a beacon with hidden SSID, we might be in for an
1743 			 * expensive search for any probe responses that should
1744 			 * be grouped with this beacon for updates ...
1745 			 */
1746 			if (!cfg80211_combine_bsses(rdev, new)) {
1747 				kfree(new);
1748 				goto drop;
1749 			}
1750 		}
1751 
1752 		if (rdev->bss_entries >= bss_entries_limit &&
1753 		    !cfg80211_bss_expire_oldest(rdev)) {
1754 			if (!list_empty(&new->hidden_list))
1755 				list_del(&new->hidden_list);
1756 			kfree(new);
1757 			goto drop;
1758 		}
1759 
1760 		/* This must be before the call to bss_ref_get */
1761 		if (tmp->pub.transmitted_bss) {
1762 			struct cfg80211_internal_bss *pbss =
1763 				container_of(tmp->pub.transmitted_bss,
1764 					     struct cfg80211_internal_bss,
1765 					     pub);
1766 
1767 			new->pub.transmitted_bss = tmp->pub.transmitted_bss;
1768 			bss_ref_get(rdev, pbss);
1769 		}
1770 
1771 		list_add_tail(&new->list, &rdev->bss_list);
1772 		rdev->bss_entries++;
1773 		rb_insert_bss(rdev, new);
1774 		found = new;
1775 	}
1776 
1777 	rdev->bss_generation++;
1778 	bss_ref_get(rdev, found);
1779 	spin_unlock_bh(&rdev->bss_lock);
1780 
1781 	return found;
1782  drop:
1783 	spin_unlock_bh(&rdev->bss_lock);
1784 	return NULL;
1785 }
1786 
1787 /*
1788  * Update RX channel information based on the available frame payload
1789  * information. This is mainly for the 2.4 GHz band where frames can be received
1790  * from neighboring channels and the Beacon frames use the DSSS Parameter Set
1791  * element to indicate the current (transmitting) channel, but this might also
1792  * be needed on other bands if RX frequency does not match with the actual
1793  * operating channel of a BSS.
1794  */
1795 static struct ieee80211_channel *
1796 cfg80211_get_bss_channel(struct wiphy *wiphy, const u8 *ie, size_t ielen,
1797 			 struct ieee80211_channel *channel,
1798 			 enum nl80211_bss_scan_width scan_width)
1799 {
1800 	const u8 *tmp;
1801 	u32 freq;
1802 	int channel_number = -1;
1803 	struct ieee80211_channel *alt_channel;
1804 
1805 	if (channel->band == NL80211_BAND_S1GHZ) {
1806 		tmp = cfg80211_find_ie(WLAN_EID_S1G_OPERATION, ie, ielen);
1807 		if (tmp && tmp[1] >= sizeof(struct ieee80211_s1g_oper_ie)) {
1808 			struct ieee80211_s1g_oper_ie *s1gop = (void *)(tmp + 2);
1809 
1810 			channel_number = s1gop->primary_ch;
1811 		}
1812 	} else {
1813 		tmp = cfg80211_find_ie(WLAN_EID_DS_PARAMS, ie, ielen);
1814 		if (tmp && tmp[1] == 1) {
1815 			channel_number = tmp[2];
1816 		} else {
1817 			tmp = cfg80211_find_ie(WLAN_EID_HT_OPERATION, ie, ielen);
1818 			if (tmp && tmp[1] >= sizeof(struct ieee80211_ht_operation)) {
1819 				struct ieee80211_ht_operation *htop = (void *)(tmp + 2);
1820 
1821 				channel_number = htop->primary_chan;
1822 			}
1823 		}
1824 	}
1825 
1826 	if (channel_number < 0) {
1827 		/* No channel information in frame payload */
1828 		return channel;
1829 	}
1830 
1831 	freq = ieee80211_channel_to_freq_khz(channel_number, channel->band);
1832 	alt_channel = ieee80211_get_channel_khz(wiphy, freq);
1833 	if (!alt_channel) {
1834 		if (channel->band == NL80211_BAND_2GHZ) {
1835 			/*
1836 			 * Better not allow unexpected channels when that could
1837 			 * be going beyond the 1-11 range (e.g., discovering
1838 			 * BSS on channel 12 when radio is configured for
1839 			 * channel 11.
1840 			 */
1841 			return NULL;
1842 		}
1843 
1844 		/* No match for the payload channel number - ignore it */
1845 		return channel;
1846 	}
1847 
1848 	if (scan_width == NL80211_BSS_CHAN_WIDTH_10 ||
1849 	    scan_width == NL80211_BSS_CHAN_WIDTH_5) {
1850 		/*
1851 		 * Ignore channel number in 5 and 10 MHz channels where there
1852 		 * may not be an n:1 or 1:n mapping between frequencies and
1853 		 * channel numbers.
1854 		 */
1855 		return channel;
1856 	}
1857 
1858 	/*
1859 	 * Use the channel determined through the payload channel number
1860 	 * instead of the RX channel reported by the driver.
1861 	 */
1862 	if (alt_channel->flags & IEEE80211_CHAN_DISABLED)
1863 		return NULL;
1864 	return alt_channel;
1865 }
1866 
1867 /* Returned bss is reference counted and must be cleaned up appropriately. */
1868 static struct cfg80211_bss *
1869 cfg80211_inform_single_bss_data(struct wiphy *wiphy,
1870 				struct cfg80211_inform_bss *data,
1871 				enum cfg80211_bss_frame_type ftype,
1872 				const u8 *bssid, u64 tsf, u16 capability,
1873 				u16 beacon_interval, const u8 *ie, size_t ielen,
1874 				struct cfg80211_non_tx_bss *non_tx_data,
1875 				gfp_t gfp)
1876 {
1877 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1878 	struct cfg80211_bss_ies *ies;
1879 	struct ieee80211_channel *channel;
1880 	struct cfg80211_internal_bss tmp = {}, *res;
1881 	int bss_type;
1882 	bool signal_valid;
1883 	unsigned long ts;
1884 
1885 	if (WARN_ON(!wiphy))
1886 		return NULL;
1887 
1888 	if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC &&
1889 		    (data->signal < 0 || data->signal > 100)))
1890 		return NULL;
1891 
1892 	channel = cfg80211_get_bss_channel(wiphy, ie, ielen, data->chan,
1893 					   data->scan_width);
1894 	if (!channel)
1895 		return NULL;
1896 
1897 	memcpy(tmp.pub.bssid, bssid, ETH_ALEN);
1898 	tmp.pub.channel = channel;
1899 	tmp.pub.scan_width = data->scan_width;
1900 	tmp.pub.signal = data->signal;
1901 	tmp.pub.beacon_interval = beacon_interval;
1902 	tmp.pub.capability = capability;
1903 	tmp.ts_boottime = data->boottime_ns;
1904 	tmp.parent_tsf = data->parent_tsf;
1905 	ether_addr_copy(tmp.parent_bssid, data->parent_bssid);
1906 
1907 	if (non_tx_data) {
1908 		tmp.pub.transmitted_bss = non_tx_data->tx_bss;
1909 		ts = bss_from_pub(non_tx_data->tx_bss)->ts;
1910 		tmp.pub.bssid_index = non_tx_data->bssid_index;
1911 		tmp.pub.max_bssid_indicator = non_tx_data->max_bssid_indicator;
1912 	} else {
1913 		ts = jiffies;
1914 	}
1915 
1916 	/*
1917 	 * If we do not know here whether the IEs are from a Beacon or Probe
1918 	 * Response frame, we need to pick one of the options and only use it
1919 	 * with the driver that does not provide the full Beacon/Probe Response
1920 	 * frame. Use Beacon frame pointer to avoid indicating that this should
1921 	 * override the IEs pointer should we have received an earlier
1922 	 * indication of Probe Response data.
1923 	 */
1924 	ies = kzalloc(sizeof(*ies) + ielen, gfp);
1925 	if (!ies)
1926 		return NULL;
1927 	ies->len = ielen;
1928 	ies->tsf = tsf;
1929 	ies->from_beacon = false;
1930 	memcpy(ies->data, ie, ielen);
1931 
1932 	switch (ftype) {
1933 	case CFG80211_BSS_FTYPE_BEACON:
1934 		ies->from_beacon = true;
1935 		fallthrough;
1936 	case CFG80211_BSS_FTYPE_UNKNOWN:
1937 		rcu_assign_pointer(tmp.pub.beacon_ies, ies);
1938 		break;
1939 	case CFG80211_BSS_FTYPE_PRESP:
1940 		rcu_assign_pointer(tmp.pub.proberesp_ies, ies);
1941 		break;
1942 	}
1943 	rcu_assign_pointer(tmp.pub.ies, ies);
1944 
1945 	signal_valid = data->chan == channel;
1946 	res = cfg80211_bss_update(wiphy_to_rdev(wiphy), &tmp, signal_valid, ts);
1947 	if (!res)
1948 		return NULL;
1949 
1950 	if (channel->band == NL80211_BAND_60GHZ) {
1951 		bss_type = res->pub.capability & WLAN_CAPABILITY_DMG_TYPE_MASK;
1952 		if (bss_type == WLAN_CAPABILITY_DMG_TYPE_AP ||
1953 		    bss_type == WLAN_CAPABILITY_DMG_TYPE_PBSS)
1954 			regulatory_hint_found_beacon(wiphy, channel, gfp);
1955 	} else {
1956 		if (res->pub.capability & WLAN_CAPABILITY_ESS)
1957 			regulatory_hint_found_beacon(wiphy, channel, gfp);
1958 	}
1959 
1960 	if (non_tx_data) {
1961 		/* this is a nontransmitting bss, we need to add it to
1962 		 * transmitting bss' list if it is not there
1963 		 */
1964 		if (cfg80211_add_nontrans_list(non_tx_data->tx_bss,
1965 					       &res->pub)) {
1966 			if (__cfg80211_unlink_bss(rdev, res))
1967 				rdev->bss_generation++;
1968 		}
1969 	}
1970 
1971 	trace_cfg80211_return_bss(&res->pub);
1972 	/* cfg80211_bss_update gives us a referenced result */
1973 	return &res->pub;
1974 }
1975 
1976 static const struct element
1977 *cfg80211_get_profile_continuation(const u8 *ie, size_t ielen,
1978 				   const struct element *mbssid_elem,
1979 				   const struct element *sub_elem)
1980 {
1981 	const u8 *mbssid_end = mbssid_elem->data + mbssid_elem->datalen;
1982 	const struct element *next_mbssid;
1983 	const struct element *next_sub;
1984 
1985 	next_mbssid = cfg80211_find_elem(WLAN_EID_MULTIPLE_BSSID,
1986 					 mbssid_end,
1987 					 ielen - (mbssid_end - ie));
1988 
1989 	/*
1990 	 * If it is not the last subelement in current MBSSID IE or there isn't
1991 	 * a next MBSSID IE - profile is complete.
1992 	*/
1993 	if ((sub_elem->data + sub_elem->datalen < mbssid_end - 1) ||
1994 	    !next_mbssid)
1995 		return NULL;
1996 
1997 	/* For any length error, just return NULL */
1998 
1999 	if (next_mbssid->datalen < 4)
2000 		return NULL;
2001 
2002 	next_sub = (void *)&next_mbssid->data[1];
2003 
2004 	if (next_mbssid->data + next_mbssid->datalen <
2005 	    next_sub->data + next_sub->datalen)
2006 		return NULL;
2007 
2008 	if (next_sub->id != 0 || next_sub->datalen < 2)
2009 		return NULL;
2010 
2011 	/*
2012 	 * Check if the first element in the next sub element is a start
2013 	 * of a new profile
2014 	 */
2015 	return next_sub->data[0] == WLAN_EID_NON_TX_BSSID_CAP ?
2016 	       NULL : next_mbssid;
2017 }
2018 
2019 size_t cfg80211_merge_profile(const u8 *ie, size_t ielen,
2020 			      const struct element *mbssid_elem,
2021 			      const struct element *sub_elem,
2022 			      u8 *merged_ie, size_t max_copy_len)
2023 {
2024 	size_t copied_len = sub_elem->datalen;
2025 	const struct element *next_mbssid;
2026 
2027 	if (sub_elem->datalen > max_copy_len)
2028 		return 0;
2029 
2030 	memcpy(merged_ie, sub_elem->data, sub_elem->datalen);
2031 
2032 	while ((next_mbssid = cfg80211_get_profile_continuation(ie, ielen,
2033 								mbssid_elem,
2034 								sub_elem))) {
2035 		const struct element *next_sub = (void *)&next_mbssid->data[1];
2036 
2037 		if (copied_len + next_sub->datalen > max_copy_len)
2038 			break;
2039 		memcpy(merged_ie + copied_len, next_sub->data,
2040 		       next_sub->datalen);
2041 		copied_len += next_sub->datalen;
2042 	}
2043 
2044 	return copied_len;
2045 }
2046 EXPORT_SYMBOL(cfg80211_merge_profile);
2047 
2048 static void cfg80211_parse_mbssid_data(struct wiphy *wiphy,
2049 				       struct cfg80211_inform_bss *data,
2050 				       enum cfg80211_bss_frame_type ftype,
2051 				       const u8 *bssid, u64 tsf,
2052 				       u16 beacon_interval, const u8 *ie,
2053 				       size_t ielen,
2054 				       struct cfg80211_non_tx_bss *non_tx_data,
2055 				       gfp_t gfp)
2056 {
2057 	const u8 *mbssid_index_ie;
2058 	const struct element *elem, *sub;
2059 	size_t new_ie_len;
2060 	u8 new_bssid[ETH_ALEN];
2061 	u8 *new_ie, *profile;
2062 	u64 seen_indices = 0;
2063 	u16 capability;
2064 	struct cfg80211_bss *bss;
2065 
2066 	if (!non_tx_data)
2067 		return;
2068 	if (!cfg80211_find_ie(WLAN_EID_MULTIPLE_BSSID, ie, ielen))
2069 		return;
2070 	if (!wiphy->support_mbssid)
2071 		return;
2072 	if (wiphy->support_only_he_mbssid &&
2073 	    !cfg80211_find_ext_ie(WLAN_EID_EXT_HE_CAPABILITY, ie, ielen))
2074 		return;
2075 
2076 	new_ie = kmalloc(IEEE80211_MAX_DATA_LEN, gfp);
2077 	if (!new_ie)
2078 		return;
2079 
2080 	profile = kmalloc(ielen, gfp);
2081 	if (!profile)
2082 		goto out;
2083 
2084 	for_each_element_id(elem, WLAN_EID_MULTIPLE_BSSID, ie, ielen) {
2085 		if (elem->datalen < 4)
2086 			continue;
2087 		for_each_element(sub, elem->data + 1, elem->datalen - 1) {
2088 			u8 profile_len;
2089 
2090 			if (sub->id != 0 || sub->datalen < 4) {
2091 				/* not a valid BSS profile */
2092 				continue;
2093 			}
2094 
2095 			if (sub->data[0] != WLAN_EID_NON_TX_BSSID_CAP ||
2096 			    sub->data[1] != 2) {
2097 				/* The first element within the Nontransmitted
2098 				 * BSSID Profile is not the Nontransmitted
2099 				 * BSSID Capability element.
2100 				 */
2101 				continue;
2102 			}
2103 
2104 			memset(profile, 0, ielen);
2105 			profile_len = cfg80211_merge_profile(ie, ielen,
2106 							     elem,
2107 							     sub,
2108 							     profile,
2109 							     ielen);
2110 
2111 			/* found a Nontransmitted BSSID Profile */
2112 			mbssid_index_ie = cfg80211_find_ie
2113 				(WLAN_EID_MULTI_BSSID_IDX,
2114 				 profile, profile_len);
2115 			if (!mbssid_index_ie || mbssid_index_ie[1] < 1 ||
2116 			    mbssid_index_ie[2] == 0 ||
2117 			    mbssid_index_ie[2] > 46) {
2118 				/* No valid Multiple BSSID-Index element */
2119 				continue;
2120 			}
2121 
2122 			if (seen_indices & BIT_ULL(mbssid_index_ie[2]))
2123 				/* We don't support legacy split of a profile */
2124 				net_dbg_ratelimited("Partial info for BSSID index %d\n",
2125 						    mbssid_index_ie[2]);
2126 
2127 			seen_indices |= BIT_ULL(mbssid_index_ie[2]);
2128 
2129 			non_tx_data->bssid_index = mbssid_index_ie[2];
2130 			non_tx_data->max_bssid_indicator = elem->data[0];
2131 
2132 			cfg80211_gen_new_bssid(bssid,
2133 					       non_tx_data->max_bssid_indicator,
2134 					       non_tx_data->bssid_index,
2135 					       new_bssid);
2136 			memset(new_ie, 0, IEEE80211_MAX_DATA_LEN);
2137 			new_ie_len = cfg80211_gen_new_ie(ie, ielen,
2138 							 profile,
2139 							 profile_len, new_ie,
2140 							 gfp);
2141 			if (!new_ie_len)
2142 				continue;
2143 
2144 			capability = get_unaligned_le16(profile + 2);
2145 			bss = cfg80211_inform_single_bss_data(wiphy, data,
2146 							      ftype,
2147 							      new_bssid, tsf,
2148 							      capability,
2149 							      beacon_interval,
2150 							      new_ie,
2151 							      new_ie_len,
2152 							      non_tx_data,
2153 							      gfp);
2154 			if (!bss)
2155 				break;
2156 			cfg80211_put_bss(wiphy, bss);
2157 		}
2158 	}
2159 
2160 out:
2161 	kfree(new_ie);
2162 	kfree(profile);
2163 }
2164 
2165 struct cfg80211_bss *
2166 cfg80211_inform_bss_data(struct wiphy *wiphy,
2167 			 struct cfg80211_inform_bss *data,
2168 			 enum cfg80211_bss_frame_type ftype,
2169 			 const u8 *bssid, u64 tsf, u16 capability,
2170 			 u16 beacon_interval, const u8 *ie, size_t ielen,
2171 			 gfp_t gfp)
2172 {
2173 	struct cfg80211_bss *res;
2174 	struct cfg80211_non_tx_bss non_tx_data;
2175 
2176 	res = cfg80211_inform_single_bss_data(wiphy, data, ftype, bssid, tsf,
2177 					      capability, beacon_interval, ie,
2178 					      ielen, NULL, gfp);
2179 	if (!res)
2180 		return NULL;
2181 	non_tx_data.tx_bss = res;
2182 	cfg80211_parse_mbssid_data(wiphy, data, ftype, bssid, tsf,
2183 				   beacon_interval, ie, ielen, &non_tx_data,
2184 				   gfp);
2185 	return res;
2186 }
2187 EXPORT_SYMBOL(cfg80211_inform_bss_data);
2188 
2189 static void
2190 cfg80211_parse_mbssid_frame_data(struct wiphy *wiphy,
2191 				 struct cfg80211_inform_bss *data,
2192 				 struct ieee80211_mgmt *mgmt, size_t len,
2193 				 struct cfg80211_non_tx_bss *non_tx_data,
2194 				 gfp_t gfp)
2195 {
2196 	enum cfg80211_bss_frame_type ftype;
2197 	const u8 *ie = mgmt->u.probe_resp.variable;
2198 	size_t ielen = len - offsetof(struct ieee80211_mgmt,
2199 				      u.probe_resp.variable);
2200 
2201 	ftype = ieee80211_is_beacon(mgmt->frame_control) ?
2202 		CFG80211_BSS_FTYPE_BEACON : CFG80211_BSS_FTYPE_PRESP;
2203 
2204 	cfg80211_parse_mbssid_data(wiphy, data, ftype, mgmt->bssid,
2205 				   le64_to_cpu(mgmt->u.probe_resp.timestamp),
2206 				   le16_to_cpu(mgmt->u.probe_resp.beacon_int),
2207 				   ie, ielen, non_tx_data, gfp);
2208 }
2209 
2210 static void
2211 cfg80211_update_notlisted_nontrans(struct wiphy *wiphy,
2212 				   struct cfg80211_bss *nontrans_bss,
2213 				   struct ieee80211_mgmt *mgmt, size_t len)
2214 {
2215 	u8 *ie, *new_ie, *pos;
2216 	const u8 *nontrans_ssid, *trans_ssid, *mbssid;
2217 	size_t ielen = len - offsetof(struct ieee80211_mgmt,
2218 				      u.probe_resp.variable);
2219 	size_t new_ie_len;
2220 	struct cfg80211_bss_ies *new_ies;
2221 	const struct cfg80211_bss_ies *old;
2222 	u8 cpy_len;
2223 
2224 	lockdep_assert_held(&wiphy_to_rdev(wiphy)->bss_lock);
2225 
2226 	ie = mgmt->u.probe_resp.variable;
2227 
2228 	new_ie_len = ielen;
2229 	trans_ssid = cfg80211_find_ie(WLAN_EID_SSID, ie, ielen);
2230 	if (!trans_ssid)
2231 		return;
2232 	new_ie_len -= trans_ssid[1];
2233 	mbssid = cfg80211_find_ie(WLAN_EID_MULTIPLE_BSSID, ie, ielen);
2234 	/*
2235 	 * It's not valid to have the MBSSID element before SSID
2236 	 * ignore if that happens - the code below assumes it is
2237 	 * after (while copying things inbetween).
2238 	 */
2239 	if (!mbssid || mbssid < trans_ssid)
2240 		return;
2241 	new_ie_len -= mbssid[1];
2242 
2243 	nontrans_ssid = ieee80211_bss_get_ie(nontrans_bss, WLAN_EID_SSID);
2244 	if (!nontrans_ssid)
2245 		return;
2246 
2247 	new_ie_len += nontrans_ssid[1];
2248 
2249 	/* generate new ie for nontrans BSS
2250 	 * 1. replace SSID with nontrans BSS' SSID
2251 	 * 2. skip MBSSID IE
2252 	 */
2253 	new_ie = kzalloc(new_ie_len, GFP_ATOMIC);
2254 	if (!new_ie)
2255 		return;
2256 
2257 	new_ies = kzalloc(sizeof(*new_ies) + new_ie_len, GFP_ATOMIC);
2258 	if (!new_ies)
2259 		goto out_free;
2260 
2261 	pos = new_ie;
2262 
2263 	/* copy the nontransmitted SSID */
2264 	cpy_len = nontrans_ssid[1] + 2;
2265 	memcpy(pos, nontrans_ssid, cpy_len);
2266 	pos += cpy_len;
2267 	/* copy the IEs between SSID and MBSSID */
2268 	cpy_len = trans_ssid[1] + 2;
2269 	memcpy(pos, (trans_ssid + cpy_len), (mbssid - (trans_ssid + cpy_len)));
2270 	pos += (mbssid - (trans_ssid + cpy_len));
2271 	/* copy the IEs after MBSSID */
2272 	cpy_len = mbssid[1] + 2;
2273 	memcpy(pos, mbssid + cpy_len, ((ie + ielen) - (mbssid + cpy_len)));
2274 
2275 	/* update ie */
2276 	new_ies->len = new_ie_len;
2277 	new_ies->tsf = le64_to_cpu(mgmt->u.probe_resp.timestamp);
2278 	new_ies->from_beacon = ieee80211_is_beacon(mgmt->frame_control);
2279 	memcpy(new_ies->data, new_ie, new_ie_len);
2280 	if (ieee80211_is_probe_resp(mgmt->frame_control)) {
2281 		old = rcu_access_pointer(nontrans_bss->proberesp_ies);
2282 		rcu_assign_pointer(nontrans_bss->proberesp_ies, new_ies);
2283 		rcu_assign_pointer(nontrans_bss->ies, new_ies);
2284 		if (old)
2285 			kfree_rcu((struct cfg80211_bss_ies *)old, rcu_head);
2286 	} else {
2287 		old = rcu_access_pointer(nontrans_bss->beacon_ies);
2288 		rcu_assign_pointer(nontrans_bss->beacon_ies, new_ies);
2289 		rcu_assign_pointer(nontrans_bss->ies, new_ies);
2290 		if (old)
2291 			kfree_rcu((struct cfg80211_bss_ies *)old, rcu_head);
2292 	}
2293 
2294 out_free:
2295 	kfree(new_ie);
2296 }
2297 
2298 /* cfg80211_inform_bss_width_frame helper */
2299 static struct cfg80211_bss *
2300 cfg80211_inform_single_bss_frame_data(struct wiphy *wiphy,
2301 				      struct cfg80211_inform_bss *data,
2302 				      struct ieee80211_mgmt *mgmt, size_t len,
2303 				      gfp_t gfp)
2304 {
2305 	struct cfg80211_internal_bss tmp = {}, *res;
2306 	struct cfg80211_bss_ies *ies;
2307 	struct ieee80211_channel *channel;
2308 	bool signal_valid;
2309 	struct ieee80211_ext *ext = NULL;
2310 	u8 *bssid, *variable;
2311 	u16 capability, beacon_int;
2312 	size_t ielen, min_hdr_len = offsetof(struct ieee80211_mgmt,
2313 					     u.probe_resp.variable);
2314 	int bss_type;
2315 
2316 	BUILD_BUG_ON(offsetof(struct ieee80211_mgmt, u.probe_resp.variable) !=
2317 			offsetof(struct ieee80211_mgmt, u.beacon.variable));
2318 
2319 	trace_cfg80211_inform_bss_frame(wiphy, data, mgmt, len);
2320 
2321 	if (WARN_ON(!mgmt))
2322 		return NULL;
2323 
2324 	if (WARN_ON(!wiphy))
2325 		return NULL;
2326 
2327 	if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC &&
2328 		    (data->signal < 0 || data->signal > 100)))
2329 		return NULL;
2330 
2331 	if (ieee80211_is_s1g_beacon(mgmt->frame_control)) {
2332 		ext = (void *) mgmt;
2333 		min_hdr_len = offsetof(struct ieee80211_ext, u.s1g_beacon);
2334 		if (ieee80211_is_s1g_short_beacon(mgmt->frame_control))
2335 			min_hdr_len = offsetof(struct ieee80211_ext,
2336 					       u.s1g_short_beacon.variable);
2337 	}
2338 
2339 	if (WARN_ON(len < min_hdr_len))
2340 		return NULL;
2341 
2342 	ielen = len - min_hdr_len;
2343 	variable = mgmt->u.probe_resp.variable;
2344 	if (ext) {
2345 		if (ieee80211_is_s1g_short_beacon(mgmt->frame_control))
2346 			variable = ext->u.s1g_short_beacon.variable;
2347 		else
2348 			variable = ext->u.s1g_beacon.variable;
2349 	}
2350 
2351 	channel = cfg80211_get_bss_channel(wiphy, variable,
2352 					   ielen, data->chan, data->scan_width);
2353 	if (!channel)
2354 		return NULL;
2355 
2356 	if (ext) {
2357 		const struct ieee80211_s1g_bcn_compat_ie *compat;
2358 		const struct element *elem;
2359 
2360 		elem = cfg80211_find_elem(WLAN_EID_S1G_BCN_COMPAT,
2361 					  variable, ielen);
2362 		if (!elem)
2363 			return NULL;
2364 		if (elem->datalen < sizeof(*compat))
2365 			return NULL;
2366 		compat = (void *)elem->data;
2367 		bssid = ext->u.s1g_beacon.sa;
2368 		capability = le16_to_cpu(compat->compat_info);
2369 		beacon_int = le16_to_cpu(compat->beacon_int);
2370 	} else {
2371 		bssid = mgmt->bssid;
2372 		beacon_int = le16_to_cpu(mgmt->u.probe_resp.beacon_int);
2373 		capability = le16_to_cpu(mgmt->u.probe_resp.capab_info);
2374 	}
2375 
2376 	ies = kzalloc(sizeof(*ies) + ielen, gfp);
2377 	if (!ies)
2378 		return NULL;
2379 	ies->len = ielen;
2380 	ies->tsf = le64_to_cpu(mgmt->u.probe_resp.timestamp);
2381 	ies->from_beacon = ieee80211_is_beacon(mgmt->frame_control) ||
2382 			   ieee80211_is_s1g_beacon(mgmt->frame_control);
2383 	memcpy(ies->data, variable, ielen);
2384 
2385 	if (ieee80211_is_probe_resp(mgmt->frame_control))
2386 		rcu_assign_pointer(tmp.pub.proberesp_ies, ies);
2387 	else
2388 		rcu_assign_pointer(tmp.pub.beacon_ies, ies);
2389 	rcu_assign_pointer(tmp.pub.ies, ies);
2390 
2391 	memcpy(tmp.pub.bssid, bssid, ETH_ALEN);
2392 	tmp.pub.beacon_interval = beacon_int;
2393 	tmp.pub.capability = capability;
2394 	tmp.pub.channel = channel;
2395 	tmp.pub.scan_width = data->scan_width;
2396 	tmp.pub.signal = data->signal;
2397 	tmp.ts_boottime = data->boottime_ns;
2398 	tmp.parent_tsf = data->parent_tsf;
2399 	tmp.pub.chains = data->chains;
2400 	memcpy(tmp.pub.chain_signal, data->chain_signal, IEEE80211_MAX_CHAINS);
2401 	ether_addr_copy(tmp.parent_bssid, data->parent_bssid);
2402 
2403 	signal_valid = data->chan == channel;
2404 	res = cfg80211_bss_update(wiphy_to_rdev(wiphy), &tmp, signal_valid,
2405 				  jiffies);
2406 	if (!res)
2407 		return NULL;
2408 
2409 	if (channel->band == NL80211_BAND_60GHZ) {
2410 		bss_type = res->pub.capability & WLAN_CAPABILITY_DMG_TYPE_MASK;
2411 		if (bss_type == WLAN_CAPABILITY_DMG_TYPE_AP ||
2412 		    bss_type == WLAN_CAPABILITY_DMG_TYPE_PBSS)
2413 			regulatory_hint_found_beacon(wiphy, channel, gfp);
2414 	} else {
2415 		if (res->pub.capability & WLAN_CAPABILITY_ESS)
2416 			regulatory_hint_found_beacon(wiphy, channel, gfp);
2417 	}
2418 
2419 	trace_cfg80211_return_bss(&res->pub);
2420 	/* cfg80211_bss_update gives us a referenced result */
2421 	return &res->pub;
2422 }
2423 
2424 struct cfg80211_bss *
2425 cfg80211_inform_bss_frame_data(struct wiphy *wiphy,
2426 			       struct cfg80211_inform_bss *data,
2427 			       struct ieee80211_mgmt *mgmt, size_t len,
2428 			       gfp_t gfp)
2429 {
2430 	struct cfg80211_bss *res, *tmp_bss;
2431 	const u8 *ie = mgmt->u.probe_resp.variable;
2432 	const struct cfg80211_bss_ies *ies1, *ies2;
2433 	size_t ielen = len - offsetof(struct ieee80211_mgmt,
2434 				      u.probe_resp.variable);
2435 	struct cfg80211_non_tx_bss non_tx_data;
2436 
2437 	res = cfg80211_inform_single_bss_frame_data(wiphy, data, mgmt,
2438 						    len, gfp);
2439 	if (!res || !wiphy->support_mbssid ||
2440 	    !cfg80211_find_ie(WLAN_EID_MULTIPLE_BSSID, ie, ielen))
2441 		return res;
2442 	if (wiphy->support_only_he_mbssid &&
2443 	    !cfg80211_find_ext_ie(WLAN_EID_EXT_HE_CAPABILITY, ie, ielen))
2444 		return res;
2445 
2446 	non_tx_data.tx_bss = res;
2447 	/* process each non-transmitting bss */
2448 	cfg80211_parse_mbssid_frame_data(wiphy, data, mgmt, len,
2449 					 &non_tx_data, gfp);
2450 
2451 	spin_lock_bh(&wiphy_to_rdev(wiphy)->bss_lock);
2452 
2453 	/* check if the res has other nontransmitting bss which is not
2454 	 * in MBSSID IE
2455 	 */
2456 	ies1 = rcu_access_pointer(res->ies);
2457 
2458 	/* go through nontrans_list, if the timestamp of the BSS is
2459 	 * earlier than the timestamp of the transmitting BSS then
2460 	 * update it
2461 	 */
2462 	list_for_each_entry(tmp_bss, &res->nontrans_list,
2463 			    nontrans_list) {
2464 		ies2 = rcu_access_pointer(tmp_bss->ies);
2465 		if (ies2->tsf < ies1->tsf)
2466 			cfg80211_update_notlisted_nontrans(wiphy, tmp_bss,
2467 							   mgmt, len);
2468 	}
2469 	spin_unlock_bh(&wiphy_to_rdev(wiphy)->bss_lock);
2470 
2471 	return res;
2472 }
2473 EXPORT_SYMBOL(cfg80211_inform_bss_frame_data);
2474 
2475 void cfg80211_ref_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
2476 {
2477 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
2478 	struct cfg80211_internal_bss *bss;
2479 
2480 	if (!pub)
2481 		return;
2482 
2483 	bss = container_of(pub, struct cfg80211_internal_bss, pub);
2484 
2485 	spin_lock_bh(&rdev->bss_lock);
2486 	bss_ref_get(rdev, bss);
2487 	spin_unlock_bh(&rdev->bss_lock);
2488 }
2489 EXPORT_SYMBOL(cfg80211_ref_bss);
2490 
2491 void cfg80211_put_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
2492 {
2493 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
2494 	struct cfg80211_internal_bss *bss;
2495 
2496 	if (!pub)
2497 		return;
2498 
2499 	bss = container_of(pub, struct cfg80211_internal_bss, pub);
2500 
2501 	spin_lock_bh(&rdev->bss_lock);
2502 	bss_ref_put(rdev, bss);
2503 	spin_unlock_bh(&rdev->bss_lock);
2504 }
2505 EXPORT_SYMBOL(cfg80211_put_bss);
2506 
2507 void cfg80211_unlink_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
2508 {
2509 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
2510 	struct cfg80211_internal_bss *bss, *tmp1;
2511 	struct cfg80211_bss *nontrans_bss, *tmp;
2512 
2513 	if (WARN_ON(!pub))
2514 		return;
2515 
2516 	bss = container_of(pub, struct cfg80211_internal_bss, pub);
2517 
2518 	spin_lock_bh(&rdev->bss_lock);
2519 	if (list_empty(&bss->list))
2520 		goto out;
2521 
2522 	list_for_each_entry_safe(nontrans_bss, tmp,
2523 				 &pub->nontrans_list,
2524 				 nontrans_list) {
2525 		tmp1 = container_of(nontrans_bss,
2526 				    struct cfg80211_internal_bss, pub);
2527 		if (__cfg80211_unlink_bss(rdev, tmp1))
2528 			rdev->bss_generation++;
2529 	}
2530 
2531 	if (__cfg80211_unlink_bss(rdev, bss))
2532 		rdev->bss_generation++;
2533 out:
2534 	spin_unlock_bh(&rdev->bss_lock);
2535 }
2536 EXPORT_SYMBOL(cfg80211_unlink_bss);
2537 
2538 void cfg80211_bss_iter(struct wiphy *wiphy,
2539 		       struct cfg80211_chan_def *chandef,
2540 		       void (*iter)(struct wiphy *wiphy,
2541 				    struct cfg80211_bss *bss,
2542 				    void *data),
2543 		       void *iter_data)
2544 {
2545 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
2546 	struct cfg80211_internal_bss *bss;
2547 
2548 	spin_lock_bh(&rdev->bss_lock);
2549 
2550 	list_for_each_entry(bss, &rdev->bss_list, list) {
2551 		if (!chandef || cfg80211_is_sub_chan(chandef, bss->pub.channel))
2552 			iter(wiphy, &bss->pub, iter_data);
2553 	}
2554 
2555 	spin_unlock_bh(&rdev->bss_lock);
2556 }
2557 EXPORT_SYMBOL(cfg80211_bss_iter);
2558 
2559 void cfg80211_update_assoc_bss_entry(struct wireless_dev *wdev,
2560 				     struct ieee80211_channel *chan)
2561 {
2562 	struct wiphy *wiphy = wdev->wiphy;
2563 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
2564 	struct cfg80211_internal_bss *cbss = wdev->current_bss;
2565 	struct cfg80211_internal_bss *new = NULL;
2566 	struct cfg80211_internal_bss *bss;
2567 	struct cfg80211_bss *nontrans_bss;
2568 	struct cfg80211_bss *tmp;
2569 
2570 	spin_lock_bh(&rdev->bss_lock);
2571 
2572 	/*
2573 	 * Some APs use CSA also for bandwidth changes, i.e., without actually
2574 	 * changing the control channel, so no need to update in such a case.
2575 	 */
2576 	if (cbss->pub.channel == chan)
2577 		goto done;
2578 
2579 	/* use transmitting bss */
2580 	if (cbss->pub.transmitted_bss)
2581 		cbss = container_of(cbss->pub.transmitted_bss,
2582 				    struct cfg80211_internal_bss,
2583 				    pub);
2584 
2585 	cbss->pub.channel = chan;
2586 
2587 	list_for_each_entry(bss, &rdev->bss_list, list) {
2588 		if (!cfg80211_bss_type_match(bss->pub.capability,
2589 					     bss->pub.channel->band,
2590 					     wdev->conn_bss_type))
2591 			continue;
2592 
2593 		if (bss == cbss)
2594 			continue;
2595 
2596 		if (!cmp_bss(&bss->pub, &cbss->pub, BSS_CMP_REGULAR)) {
2597 			new = bss;
2598 			break;
2599 		}
2600 	}
2601 
2602 	if (new) {
2603 		/* to save time, update IEs for transmitting bss only */
2604 		if (cfg80211_update_known_bss(rdev, cbss, new, false)) {
2605 			new->pub.proberesp_ies = NULL;
2606 			new->pub.beacon_ies = NULL;
2607 		}
2608 
2609 		list_for_each_entry_safe(nontrans_bss, tmp,
2610 					 &new->pub.nontrans_list,
2611 					 nontrans_list) {
2612 			bss = container_of(nontrans_bss,
2613 					   struct cfg80211_internal_bss, pub);
2614 			if (__cfg80211_unlink_bss(rdev, bss))
2615 				rdev->bss_generation++;
2616 		}
2617 
2618 		WARN_ON(atomic_read(&new->hold));
2619 		if (!WARN_ON(!__cfg80211_unlink_bss(rdev, new)))
2620 			rdev->bss_generation++;
2621 	}
2622 
2623 	rb_erase(&cbss->rbn, &rdev->bss_tree);
2624 	rb_insert_bss(rdev, cbss);
2625 	rdev->bss_generation++;
2626 
2627 	list_for_each_entry_safe(nontrans_bss, tmp,
2628 				 &cbss->pub.nontrans_list,
2629 				 nontrans_list) {
2630 		bss = container_of(nontrans_bss,
2631 				   struct cfg80211_internal_bss, pub);
2632 		bss->pub.channel = chan;
2633 		rb_erase(&bss->rbn, &rdev->bss_tree);
2634 		rb_insert_bss(rdev, bss);
2635 		rdev->bss_generation++;
2636 	}
2637 
2638 done:
2639 	spin_unlock_bh(&rdev->bss_lock);
2640 }
2641 
2642 #ifdef CONFIG_CFG80211_WEXT
2643 static struct cfg80211_registered_device *
2644 cfg80211_get_dev_from_ifindex(struct net *net, int ifindex)
2645 {
2646 	struct cfg80211_registered_device *rdev;
2647 	struct net_device *dev;
2648 
2649 	ASSERT_RTNL();
2650 
2651 	dev = dev_get_by_index(net, ifindex);
2652 	if (!dev)
2653 		return ERR_PTR(-ENODEV);
2654 	if (dev->ieee80211_ptr)
2655 		rdev = wiphy_to_rdev(dev->ieee80211_ptr->wiphy);
2656 	else
2657 		rdev = ERR_PTR(-ENODEV);
2658 	dev_put(dev);
2659 	return rdev;
2660 }
2661 
2662 int cfg80211_wext_siwscan(struct net_device *dev,
2663 			  struct iw_request_info *info,
2664 			  union iwreq_data *wrqu, char *extra)
2665 {
2666 	struct cfg80211_registered_device *rdev;
2667 	struct wiphy *wiphy;
2668 	struct iw_scan_req *wreq = NULL;
2669 	struct cfg80211_scan_request *creq = NULL;
2670 	int i, err, n_channels = 0;
2671 	enum nl80211_band band;
2672 
2673 	if (!netif_running(dev))
2674 		return -ENETDOWN;
2675 
2676 	if (wrqu->data.length == sizeof(struct iw_scan_req))
2677 		wreq = (struct iw_scan_req *)extra;
2678 
2679 	rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
2680 
2681 	if (IS_ERR(rdev))
2682 		return PTR_ERR(rdev);
2683 
2684 	if (rdev->scan_req || rdev->scan_msg) {
2685 		err = -EBUSY;
2686 		goto out;
2687 	}
2688 
2689 	wiphy = &rdev->wiphy;
2690 
2691 	/* Determine number of channels, needed to allocate creq */
2692 	if (wreq && wreq->num_channels)
2693 		n_channels = wreq->num_channels;
2694 	else
2695 		n_channels = ieee80211_get_num_supported_channels(wiphy);
2696 
2697 	creq = kzalloc(sizeof(*creq) + sizeof(struct cfg80211_ssid) +
2698 		       n_channels * sizeof(void *),
2699 		       GFP_ATOMIC);
2700 	if (!creq) {
2701 		err = -ENOMEM;
2702 		goto out;
2703 	}
2704 
2705 	creq->wiphy = wiphy;
2706 	creq->wdev = dev->ieee80211_ptr;
2707 	/* SSIDs come after channels */
2708 	creq->ssids = (void *)&creq->channels[n_channels];
2709 	creq->n_channels = n_channels;
2710 	creq->n_ssids = 1;
2711 	creq->scan_start = jiffies;
2712 
2713 	/* translate "Scan on frequencies" request */
2714 	i = 0;
2715 	for (band = 0; band < NUM_NL80211_BANDS; band++) {
2716 		int j;
2717 
2718 		if (!wiphy->bands[band])
2719 			continue;
2720 
2721 		for (j = 0; j < wiphy->bands[band]->n_channels; j++) {
2722 			/* ignore disabled channels */
2723 			if (wiphy->bands[band]->channels[j].flags &
2724 						IEEE80211_CHAN_DISABLED)
2725 				continue;
2726 
2727 			/* If we have a wireless request structure and the
2728 			 * wireless request specifies frequencies, then search
2729 			 * for the matching hardware channel.
2730 			 */
2731 			if (wreq && wreq->num_channels) {
2732 				int k;
2733 				int wiphy_freq = wiphy->bands[band]->channels[j].center_freq;
2734 				for (k = 0; k < wreq->num_channels; k++) {
2735 					struct iw_freq *freq =
2736 						&wreq->channel_list[k];
2737 					int wext_freq =
2738 						cfg80211_wext_freq(freq);
2739 
2740 					if (wext_freq == wiphy_freq)
2741 						goto wext_freq_found;
2742 				}
2743 				goto wext_freq_not_found;
2744 			}
2745 
2746 		wext_freq_found:
2747 			creq->channels[i] = &wiphy->bands[band]->channels[j];
2748 			i++;
2749 		wext_freq_not_found: ;
2750 		}
2751 	}
2752 	/* No channels found? */
2753 	if (!i) {
2754 		err = -EINVAL;
2755 		goto out;
2756 	}
2757 
2758 	/* Set real number of channels specified in creq->channels[] */
2759 	creq->n_channels = i;
2760 
2761 	/* translate "Scan for SSID" request */
2762 	if (wreq) {
2763 		if (wrqu->data.flags & IW_SCAN_THIS_ESSID) {
2764 			if (wreq->essid_len > IEEE80211_MAX_SSID_LEN) {
2765 				err = -EINVAL;
2766 				goto out;
2767 			}
2768 			memcpy(creq->ssids[0].ssid, wreq->essid, wreq->essid_len);
2769 			creq->ssids[0].ssid_len = wreq->essid_len;
2770 		}
2771 		if (wreq->scan_type == IW_SCAN_TYPE_PASSIVE)
2772 			creq->n_ssids = 0;
2773 	}
2774 
2775 	for (i = 0; i < NUM_NL80211_BANDS; i++)
2776 		if (wiphy->bands[i])
2777 			creq->rates[i] = (1 << wiphy->bands[i]->n_bitrates) - 1;
2778 
2779 	eth_broadcast_addr(creq->bssid);
2780 
2781 	wiphy_lock(&rdev->wiphy);
2782 
2783 	rdev->scan_req = creq;
2784 	err = rdev_scan(rdev, creq);
2785 	if (err) {
2786 		rdev->scan_req = NULL;
2787 		/* creq will be freed below */
2788 	} else {
2789 		nl80211_send_scan_start(rdev, dev->ieee80211_ptr);
2790 		/* creq now owned by driver */
2791 		creq = NULL;
2792 		dev_hold(dev);
2793 	}
2794 	wiphy_unlock(&rdev->wiphy);
2795  out:
2796 	kfree(creq);
2797 	return err;
2798 }
2799 EXPORT_WEXT_HANDLER(cfg80211_wext_siwscan);
2800 
2801 static char *ieee80211_scan_add_ies(struct iw_request_info *info,
2802 				    const struct cfg80211_bss_ies *ies,
2803 				    char *current_ev, char *end_buf)
2804 {
2805 	const u8 *pos, *end, *next;
2806 	struct iw_event iwe;
2807 
2808 	if (!ies)
2809 		return current_ev;
2810 
2811 	/*
2812 	 * If needed, fragment the IEs buffer (at IE boundaries) into short
2813 	 * enough fragments to fit into IW_GENERIC_IE_MAX octet messages.
2814 	 */
2815 	pos = ies->data;
2816 	end = pos + ies->len;
2817 
2818 	while (end - pos > IW_GENERIC_IE_MAX) {
2819 		next = pos + 2 + pos[1];
2820 		while (next + 2 + next[1] - pos < IW_GENERIC_IE_MAX)
2821 			next = next + 2 + next[1];
2822 
2823 		memset(&iwe, 0, sizeof(iwe));
2824 		iwe.cmd = IWEVGENIE;
2825 		iwe.u.data.length = next - pos;
2826 		current_ev = iwe_stream_add_point_check(info, current_ev,
2827 							end_buf, &iwe,
2828 							(void *)pos);
2829 		if (IS_ERR(current_ev))
2830 			return current_ev;
2831 		pos = next;
2832 	}
2833 
2834 	if (end > pos) {
2835 		memset(&iwe, 0, sizeof(iwe));
2836 		iwe.cmd = IWEVGENIE;
2837 		iwe.u.data.length = end - pos;
2838 		current_ev = iwe_stream_add_point_check(info, current_ev,
2839 							end_buf, &iwe,
2840 							(void *)pos);
2841 		if (IS_ERR(current_ev))
2842 			return current_ev;
2843 	}
2844 
2845 	return current_ev;
2846 }
2847 
2848 static char *
2849 ieee80211_bss(struct wiphy *wiphy, struct iw_request_info *info,
2850 	      struct cfg80211_internal_bss *bss, char *current_ev,
2851 	      char *end_buf)
2852 {
2853 	const struct cfg80211_bss_ies *ies;
2854 	struct iw_event iwe;
2855 	const u8 *ie;
2856 	u8 buf[50];
2857 	u8 *cfg, *p, *tmp;
2858 	int rem, i, sig;
2859 	bool ismesh = false;
2860 
2861 	memset(&iwe, 0, sizeof(iwe));
2862 	iwe.cmd = SIOCGIWAP;
2863 	iwe.u.ap_addr.sa_family = ARPHRD_ETHER;
2864 	memcpy(iwe.u.ap_addr.sa_data, bss->pub.bssid, ETH_ALEN);
2865 	current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe,
2866 						IW_EV_ADDR_LEN);
2867 	if (IS_ERR(current_ev))
2868 		return current_ev;
2869 
2870 	memset(&iwe, 0, sizeof(iwe));
2871 	iwe.cmd = SIOCGIWFREQ;
2872 	iwe.u.freq.m = ieee80211_frequency_to_channel(bss->pub.channel->center_freq);
2873 	iwe.u.freq.e = 0;
2874 	current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe,
2875 						IW_EV_FREQ_LEN);
2876 	if (IS_ERR(current_ev))
2877 		return current_ev;
2878 
2879 	memset(&iwe, 0, sizeof(iwe));
2880 	iwe.cmd = SIOCGIWFREQ;
2881 	iwe.u.freq.m = bss->pub.channel->center_freq;
2882 	iwe.u.freq.e = 6;
2883 	current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe,
2884 						IW_EV_FREQ_LEN);
2885 	if (IS_ERR(current_ev))
2886 		return current_ev;
2887 
2888 	if (wiphy->signal_type != CFG80211_SIGNAL_TYPE_NONE) {
2889 		memset(&iwe, 0, sizeof(iwe));
2890 		iwe.cmd = IWEVQUAL;
2891 		iwe.u.qual.updated = IW_QUAL_LEVEL_UPDATED |
2892 				     IW_QUAL_NOISE_INVALID |
2893 				     IW_QUAL_QUAL_UPDATED;
2894 		switch (wiphy->signal_type) {
2895 		case CFG80211_SIGNAL_TYPE_MBM:
2896 			sig = bss->pub.signal / 100;
2897 			iwe.u.qual.level = sig;
2898 			iwe.u.qual.updated |= IW_QUAL_DBM;
2899 			if (sig < -110)		/* rather bad */
2900 				sig = -110;
2901 			else if (sig > -40)	/* perfect */
2902 				sig = -40;
2903 			/* will give a range of 0 .. 70 */
2904 			iwe.u.qual.qual = sig + 110;
2905 			break;
2906 		case CFG80211_SIGNAL_TYPE_UNSPEC:
2907 			iwe.u.qual.level = bss->pub.signal;
2908 			/* will give range 0 .. 100 */
2909 			iwe.u.qual.qual = bss->pub.signal;
2910 			break;
2911 		default:
2912 			/* not reached */
2913 			break;
2914 		}
2915 		current_ev = iwe_stream_add_event_check(info, current_ev,
2916 							end_buf, &iwe,
2917 							IW_EV_QUAL_LEN);
2918 		if (IS_ERR(current_ev))
2919 			return current_ev;
2920 	}
2921 
2922 	memset(&iwe, 0, sizeof(iwe));
2923 	iwe.cmd = SIOCGIWENCODE;
2924 	if (bss->pub.capability & WLAN_CAPABILITY_PRIVACY)
2925 		iwe.u.data.flags = IW_ENCODE_ENABLED | IW_ENCODE_NOKEY;
2926 	else
2927 		iwe.u.data.flags = IW_ENCODE_DISABLED;
2928 	iwe.u.data.length = 0;
2929 	current_ev = iwe_stream_add_point_check(info, current_ev, end_buf,
2930 						&iwe, "");
2931 	if (IS_ERR(current_ev))
2932 		return current_ev;
2933 
2934 	rcu_read_lock();
2935 	ies = rcu_dereference(bss->pub.ies);
2936 	rem = ies->len;
2937 	ie = ies->data;
2938 
2939 	while (rem >= 2) {
2940 		/* invalid data */
2941 		if (ie[1] > rem - 2)
2942 			break;
2943 
2944 		switch (ie[0]) {
2945 		case WLAN_EID_SSID:
2946 			memset(&iwe, 0, sizeof(iwe));
2947 			iwe.cmd = SIOCGIWESSID;
2948 			iwe.u.data.length = ie[1];
2949 			iwe.u.data.flags = 1;
2950 			current_ev = iwe_stream_add_point_check(info,
2951 								current_ev,
2952 								end_buf, &iwe,
2953 								(u8 *)ie + 2);
2954 			if (IS_ERR(current_ev))
2955 				goto unlock;
2956 			break;
2957 		case WLAN_EID_MESH_ID:
2958 			memset(&iwe, 0, sizeof(iwe));
2959 			iwe.cmd = SIOCGIWESSID;
2960 			iwe.u.data.length = ie[1];
2961 			iwe.u.data.flags = 1;
2962 			current_ev = iwe_stream_add_point_check(info,
2963 								current_ev,
2964 								end_buf, &iwe,
2965 								(u8 *)ie + 2);
2966 			if (IS_ERR(current_ev))
2967 				goto unlock;
2968 			break;
2969 		case WLAN_EID_MESH_CONFIG:
2970 			ismesh = true;
2971 			if (ie[1] != sizeof(struct ieee80211_meshconf_ie))
2972 				break;
2973 			cfg = (u8 *)ie + 2;
2974 			memset(&iwe, 0, sizeof(iwe));
2975 			iwe.cmd = IWEVCUSTOM;
2976 			sprintf(buf, "Mesh Network Path Selection Protocol ID: "
2977 				"0x%02X", cfg[0]);
2978 			iwe.u.data.length = strlen(buf);
2979 			current_ev = iwe_stream_add_point_check(info,
2980 								current_ev,
2981 								end_buf,
2982 								&iwe, buf);
2983 			if (IS_ERR(current_ev))
2984 				goto unlock;
2985 			sprintf(buf, "Path Selection Metric ID: 0x%02X",
2986 				cfg[1]);
2987 			iwe.u.data.length = strlen(buf);
2988 			current_ev = iwe_stream_add_point_check(info,
2989 								current_ev,
2990 								end_buf,
2991 								&iwe, buf);
2992 			if (IS_ERR(current_ev))
2993 				goto unlock;
2994 			sprintf(buf, "Congestion Control Mode ID: 0x%02X",
2995 				cfg[2]);
2996 			iwe.u.data.length = strlen(buf);
2997 			current_ev = iwe_stream_add_point_check(info,
2998 								current_ev,
2999 								end_buf,
3000 								&iwe, buf);
3001 			if (IS_ERR(current_ev))
3002 				goto unlock;
3003 			sprintf(buf, "Synchronization ID: 0x%02X", cfg[3]);
3004 			iwe.u.data.length = strlen(buf);
3005 			current_ev = iwe_stream_add_point_check(info,
3006 								current_ev,
3007 								end_buf,
3008 								&iwe, buf);
3009 			if (IS_ERR(current_ev))
3010 				goto unlock;
3011 			sprintf(buf, "Authentication ID: 0x%02X", cfg[4]);
3012 			iwe.u.data.length = strlen(buf);
3013 			current_ev = iwe_stream_add_point_check(info,
3014 								current_ev,
3015 								end_buf,
3016 								&iwe, buf);
3017 			if (IS_ERR(current_ev))
3018 				goto unlock;
3019 			sprintf(buf, "Formation Info: 0x%02X", cfg[5]);
3020 			iwe.u.data.length = strlen(buf);
3021 			current_ev = iwe_stream_add_point_check(info,
3022 								current_ev,
3023 								end_buf,
3024 								&iwe, buf);
3025 			if (IS_ERR(current_ev))
3026 				goto unlock;
3027 			sprintf(buf, "Capabilities: 0x%02X", cfg[6]);
3028 			iwe.u.data.length = strlen(buf);
3029 			current_ev = iwe_stream_add_point_check(info,
3030 								current_ev,
3031 								end_buf,
3032 								&iwe, buf);
3033 			if (IS_ERR(current_ev))
3034 				goto unlock;
3035 			break;
3036 		case WLAN_EID_SUPP_RATES:
3037 		case WLAN_EID_EXT_SUPP_RATES:
3038 			/* display all supported rates in readable format */
3039 			p = current_ev + iwe_stream_lcp_len(info);
3040 
3041 			memset(&iwe, 0, sizeof(iwe));
3042 			iwe.cmd = SIOCGIWRATE;
3043 			/* Those two flags are ignored... */
3044 			iwe.u.bitrate.fixed = iwe.u.bitrate.disabled = 0;
3045 
3046 			for (i = 0; i < ie[1]; i++) {
3047 				iwe.u.bitrate.value =
3048 					((ie[i + 2] & 0x7f) * 500000);
3049 				tmp = p;
3050 				p = iwe_stream_add_value(info, current_ev, p,
3051 							 end_buf, &iwe,
3052 							 IW_EV_PARAM_LEN);
3053 				if (p == tmp) {
3054 					current_ev = ERR_PTR(-E2BIG);
3055 					goto unlock;
3056 				}
3057 			}
3058 			current_ev = p;
3059 			break;
3060 		}
3061 		rem -= ie[1] + 2;
3062 		ie += ie[1] + 2;
3063 	}
3064 
3065 	if (bss->pub.capability & (WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS) ||
3066 	    ismesh) {
3067 		memset(&iwe, 0, sizeof(iwe));
3068 		iwe.cmd = SIOCGIWMODE;
3069 		if (ismesh)
3070 			iwe.u.mode = IW_MODE_MESH;
3071 		else if (bss->pub.capability & WLAN_CAPABILITY_ESS)
3072 			iwe.u.mode = IW_MODE_MASTER;
3073 		else
3074 			iwe.u.mode = IW_MODE_ADHOC;
3075 		current_ev = iwe_stream_add_event_check(info, current_ev,
3076 							end_buf, &iwe,
3077 							IW_EV_UINT_LEN);
3078 		if (IS_ERR(current_ev))
3079 			goto unlock;
3080 	}
3081 
3082 	memset(&iwe, 0, sizeof(iwe));
3083 	iwe.cmd = IWEVCUSTOM;
3084 	sprintf(buf, "tsf=%016llx", (unsigned long long)(ies->tsf));
3085 	iwe.u.data.length = strlen(buf);
3086 	current_ev = iwe_stream_add_point_check(info, current_ev, end_buf,
3087 						&iwe, buf);
3088 	if (IS_ERR(current_ev))
3089 		goto unlock;
3090 	memset(&iwe, 0, sizeof(iwe));
3091 	iwe.cmd = IWEVCUSTOM;
3092 	sprintf(buf, " Last beacon: %ums ago",
3093 		elapsed_jiffies_msecs(bss->ts));
3094 	iwe.u.data.length = strlen(buf);
3095 	current_ev = iwe_stream_add_point_check(info, current_ev,
3096 						end_buf, &iwe, buf);
3097 	if (IS_ERR(current_ev))
3098 		goto unlock;
3099 
3100 	current_ev = ieee80211_scan_add_ies(info, ies, current_ev, end_buf);
3101 
3102  unlock:
3103 	rcu_read_unlock();
3104 	return current_ev;
3105 }
3106 
3107 
3108 static int ieee80211_scan_results(struct cfg80211_registered_device *rdev,
3109 				  struct iw_request_info *info,
3110 				  char *buf, size_t len)
3111 {
3112 	char *current_ev = buf;
3113 	char *end_buf = buf + len;
3114 	struct cfg80211_internal_bss *bss;
3115 	int err = 0;
3116 
3117 	spin_lock_bh(&rdev->bss_lock);
3118 	cfg80211_bss_expire(rdev);
3119 
3120 	list_for_each_entry(bss, &rdev->bss_list, list) {
3121 		if (buf + len - current_ev <= IW_EV_ADDR_LEN) {
3122 			err = -E2BIG;
3123 			break;
3124 		}
3125 		current_ev = ieee80211_bss(&rdev->wiphy, info, bss,
3126 					   current_ev, end_buf);
3127 		if (IS_ERR(current_ev)) {
3128 			err = PTR_ERR(current_ev);
3129 			break;
3130 		}
3131 	}
3132 	spin_unlock_bh(&rdev->bss_lock);
3133 
3134 	if (err)
3135 		return err;
3136 	return current_ev - buf;
3137 }
3138 
3139 
3140 int cfg80211_wext_giwscan(struct net_device *dev,
3141 			  struct iw_request_info *info,
3142 			  struct iw_point *data, char *extra)
3143 {
3144 	struct cfg80211_registered_device *rdev;
3145 	int res;
3146 
3147 	if (!netif_running(dev))
3148 		return -ENETDOWN;
3149 
3150 	rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
3151 
3152 	if (IS_ERR(rdev))
3153 		return PTR_ERR(rdev);
3154 
3155 	if (rdev->scan_req || rdev->scan_msg)
3156 		return -EAGAIN;
3157 
3158 	res = ieee80211_scan_results(rdev, info, extra, data->length);
3159 	data->length = 0;
3160 	if (res >= 0) {
3161 		data->length = res;
3162 		res = 0;
3163 	}
3164 
3165 	return res;
3166 }
3167 EXPORT_WEXT_HANDLER(cfg80211_wext_giwscan);
3168 #endif
3169