xref: /openbmc/linux/net/wireless/scan.c (revision aa311596)
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) 2018-2023 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  * @psd_20: The 20MHz PSD EIRP of the primary 20MHz channel for the reported AP
100  */
101 struct cfg80211_colocated_ap {
102 	struct list_head list;
103 	u8 bssid[ETH_ALEN];
104 	u8 ssid[IEEE80211_MAX_SSID_LEN];
105 	size_t ssid_len;
106 	u32 short_ssid;
107 	u32 center_freq;
108 	u8 unsolicited_probe:1,
109 	   oct_recommended:1,
110 	   same_ssid:1,
111 	   multi_bss:1,
112 	   transmitted_bssid:1,
113 	   colocated_ess:1,
114 	   short_ssid_valid:1;
115 	s8 psd_20;
116 };
117 
118 static void bss_free(struct cfg80211_internal_bss *bss)
119 {
120 	struct cfg80211_bss_ies *ies;
121 
122 	if (WARN_ON(atomic_read(&bss->hold)))
123 		return;
124 
125 	ies = (void *)rcu_access_pointer(bss->pub.beacon_ies);
126 	if (ies && !bss->pub.hidden_beacon_bss)
127 		kfree_rcu(ies, rcu_head);
128 	ies = (void *)rcu_access_pointer(bss->pub.proberesp_ies);
129 	if (ies)
130 		kfree_rcu(ies, rcu_head);
131 
132 	/*
133 	 * This happens when the module is removed, it doesn't
134 	 * really matter any more save for completeness
135 	 */
136 	if (!list_empty(&bss->hidden_list))
137 		list_del(&bss->hidden_list);
138 
139 	kfree(bss);
140 }
141 
142 static inline void bss_ref_get(struct cfg80211_registered_device *rdev,
143 			       struct cfg80211_internal_bss *bss)
144 {
145 	lockdep_assert_held(&rdev->bss_lock);
146 
147 	bss->refcount++;
148 
149 	if (bss->pub.hidden_beacon_bss)
150 		bss_from_pub(bss->pub.hidden_beacon_bss)->refcount++;
151 
152 	if (bss->pub.transmitted_bss)
153 		bss_from_pub(bss->pub.transmitted_bss)->refcount++;
154 }
155 
156 static inline void bss_ref_put(struct cfg80211_registered_device *rdev,
157 			       struct cfg80211_internal_bss *bss)
158 {
159 	lockdep_assert_held(&rdev->bss_lock);
160 
161 	if (bss->pub.hidden_beacon_bss) {
162 		struct cfg80211_internal_bss *hbss;
163 
164 		hbss = bss_from_pub(bss->pub.hidden_beacon_bss);
165 		hbss->refcount--;
166 		if (hbss->refcount == 0)
167 			bss_free(hbss);
168 	}
169 
170 	if (bss->pub.transmitted_bss) {
171 		struct cfg80211_internal_bss *tbss;
172 
173 		tbss = bss_from_pub(bss->pub.transmitted_bss);
174 		tbss->refcount--;
175 		if (tbss->refcount == 0)
176 			bss_free(tbss);
177 	}
178 
179 	bss->refcount--;
180 	if (bss->refcount == 0)
181 		bss_free(bss);
182 }
183 
184 static bool __cfg80211_unlink_bss(struct cfg80211_registered_device *rdev,
185 				  struct cfg80211_internal_bss *bss)
186 {
187 	lockdep_assert_held(&rdev->bss_lock);
188 
189 	if (!list_empty(&bss->hidden_list)) {
190 		/*
191 		 * don't remove the beacon entry if it has
192 		 * probe responses associated with it
193 		 */
194 		if (!bss->pub.hidden_beacon_bss)
195 			return false;
196 		/*
197 		 * if it's a probe response entry break its
198 		 * link to the other entries in the group
199 		 */
200 		list_del_init(&bss->hidden_list);
201 	}
202 
203 	list_del_init(&bss->list);
204 	list_del_init(&bss->pub.nontrans_list);
205 	rb_erase(&bss->rbn, &rdev->bss_tree);
206 	rdev->bss_entries--;
207 	WARN_ONCE((rdev->bss_entries == 0) ^ list_empty(&rdev->bss_list),
208 		  "rdev bss entries[%d]/list[empty:%d] corruption\n",
209 		  rdev->bss_entries, list_empty(&rdev->bss_list));
210 	bss_ref_put(rdev, bss);
211 	return true;
212 }
213 
214 bool cfg80211_is_element_inherited(const struct element *elem,
215 				   const struct element *non_inherit_elem)
216 {
217 	u8 id_len, ext_id_len, i, loop_len, id;
218 	const u8 *list;
219 
220 	if (elem->id == WLAN_EID_MULTIPLE_BSSID)
221 		return false;
222 
223 	if (elem->id == WLAN_EID_EXTENSION && elem->datalen > 1 &&
224 	    elem->data[0] == WLAN_EID_EXT_EHT_MULTI_LINK)
225 		return false;
226 
227 	if (!non_inherit_elem || non_inherit_elem->datalen < 2)
228 		return true;
229 
230 	/*
231 	 * non inheritance element format is:
232 	 * ext ID (56) | IDs list len | list | extension IDs list len | list
233 	 * Both lists are optional. Both lengths are mandatory.
234 	 * This means valid length is:
235 	 * elem_len = 1 (extension ID) + 2 (list len fields) + list lengths
236 	 */
237 	id_len = non_inherit_elem->data[1];
238 	if (non_inherit_elem->datalen < 3 + id_len)
239 		return true;
240 
241 	ext_id_len = non_inherit_elem->data[2 + id_len];
242 	if (non_inherit_elem->datalen < 3 + id_len + ext_id_len)
243 		return true;
244 
245 	if (elem->id == WLAN_EID_EXTENSION) {
246 		if (!ext_id_len)
247 			return true;
248 		loop_len = ext_id_len;
249 		list = &non_inherit_elem->data[3 + id_len];
250 		id = elem->data[0];
251 	} else {
252 		if (!id_len)
253 			return true;
254 		loop_len = id_len;
255 		list = &non_inherit_elem->data[2];
256 		id = elem->id;
257 	}
258 
259 	for (i = 0; i < loop_len; i++) {
260 		if (list[i] == id)
261 			return false;
262 	}
263 
264 	return true;
265 }
266 EXPORT_SYMBOL(cfg80211_is_element_inherited);
267 
268 static size_t cfg80211_copy_elem_with_frags(const struct element *elem,
269 					    const u8 *ie, size_t ie_len,
270 					    u8 **pos, u8 *buf, size_t buf_len)
271 {
272 	if (WARN_ON((u8 *)elem < ie || elem->data > ie + ie_len ||
273 		    elem->data + elem->datalen > ie + ie_len))
274 		return 0;
275 
276 	if (elem->datalen + 2 > buf + buf_len - *pos)
277 		return 0;
278 
279 	memcpy(*pos, elem, elem->datalen + 2);
280 	*pos += elem->datalen + 2;
281 
282 	/* Finish if it is not fragmented  */
283 	if (elem->datalen != 255)
284 		return *pos - buf;
285 
286 	ie_len = ie + ie_len - elem->data - elem->datalen;
287 	ie = (const u8 *)elem->data + elem->datalen;
288 
289 	for_each_element(elem, ie, ie_len) {
290 		if (elem->id != WLAN_EID_FRAGMENT)
291 			break;
292 
293 		if (elem->datalen + 2 > buf + buf_len - *pos)
294 			return 0;
295 
296 		memcpy(*pos, elem, elem->datalen + 2);
297 		*pos += elem->datalen + 2;
298 
299 		if (elem->datalen != 255)
300 			break;
301 	}
302 
303 	return *pos - buf;
304 }
305 
306 static size_t cfg80211_gen_new_ie(const u8 *ie, size_t ielen,
307 				  const u8 *subie, size_t subie_len,
308 				  u8 *new_ie, size_t new_ie_len)
309 {
310 	const struct element *non_inherit_elem, *parent, *sub;
311 	u8 *pos = new_ie;
312 	u8 id, ext_id;
313 	unsigned int match_len;
314 
315 	non_inherit_elem = cfg80211_find_ext_elem(WLAN_EID_EXT_NON_INHERITANCE,
316 						  subie, subie_len);
317 
318 	/* We copy the elements one by one from the parent to the generated
319 	 * elements.
320 	 * If they are not inherited (included in subie or in the non
321 	 * inheritance element), then we copy all occurrences the first time
322 	 * we see this element type.
323 	 */
324 	for_each_element(parent, ie, ielen) {
325 		if (parent->id == WLAN_EID_FRAGMENT)
326 			continue;
327 
328 		if (parent->id == WLAN_EID_EXTENSION) {
329 			if (parent->datalen < 1)
330 				continue;
331 
332 			id = WLAN_EID_EXTENSION;
333 			ext_id = parent->data[0];
334 			match_len = 1;
335 		} else {
336 			id = parent->id;
337 			match_len = 0;
338 		}
339 
340 		/* Find first occurrence in subie */
341 		sub = cfg80211_find_elem_match(id, subie, subie_len,
342 					       &ext_id, match_len, 0);
343 
344 		/* Copy from parent if not in subie and inherited */
345 		if (!sub &&
346 		    cfg80211_is_element_inherited(parent, non_inherit_elem)) {
347 			if (!cfg80211_copy_elem_with_frags(parent,
348 							   ie, ielen,
349 							   &pos, new_ie,
350 							   new_ie_len))
351 				return 0;
352 
353 			continue;
354 		}
355 
356 		/* Already copied if an earlier element had the same type */
357 		if (cfg80211_find_elem_match(id, ie, (u8 *)parent - ie,
358 					     &ext_id, match_len, 0))
359 			continue;
360 
361 		/* Not inheriting, copy all similar elements from subie */
362 		while (sub) {
363 			if (!cfg80211_copy_elem_with_frags(sub,
364 							   subie, subie_len,
365 							   &pos, new_ie,
366 							   new_ie_len))
367 				return 0;
368 
369 			sub = cfg80211_find_elem_match(id,
370 						       sub->data + sub->datalen,
371 						       subie_len + subie -
372 						       (sub->data +
373 							sub->datalen),
374 						       &ext_id, match_len, 0);
375 		}
376 	}
377 
378 	/* The above misses elements that are included in subie but not in the
379 	 * parent, so do a pass over subie and append those.
380 	 * Skip the non-tx BSSID caps and non-inheritance element.
381 	 */
382 	for_each_element(sub, subie, subie_len) {
383 		if (sub->id == WLAN_EID_NON_TX_BSSID_CAP)
384 			continue;
385 
386 		if (sub->id == WLAN_EID_FRAGMENT)
387 			continue;
388 
389 		if (sub->id == WLAN_EID_EXTENSION) {
390 			if (sub->datalen < 1)
391 				continue;
392 
393 			id = WLAN_EID_EXTENSION;
394 			ext_id = sub->data[0];
395 			match_len = 1;
396 
397 			if (ext_id == WLAN_EID_EXT_NON_INHERITANCE)
398 				continue;
399 		} else {
400 			id = sub->id;
401 			match_len = 0;
402 		}
403 
404 		/* Processed if one was included in the parent */
405 		if (cfg80211_find_elem_match(id, ie, ielen,
406 					     &ext_id, match_len, 0))
407 			continue;
408 
409 		if (!cfg80211_copy_elem_with_frags(sub, subie, subie_len,
410 						   &pos, new_ie, new_ie_len))
411 			return 0;
412 	}
413 
414 	return pos - new_ie;
415 }
416 
417 static bool is_bss(struct cfg80211_bss *a, const u8 *bssid,
418 		   const u8 *ssid, size_t ssid_len)
419 {
420 	const struct cfg80211_bss_ies *ies;
421 	const struct element *ssid_elem;
422 
423 	if (bssid && !ether_addr_equal(a->bssid, bssid))
424 		return false;
425 
426 	if (!ssid)
427 		return true;
428 
429 	ies = rcu_access_pointer(a->ies);
430 	if (!ies)
431 		return false;
432 	ssid_elem = cfg80211_find_elem(WLAN_EID_SSID, ies->data, ies->len);
433 	if (!ssid_elem)
434 		return false;
435 	if (ssid_elem->datalen != ssid_len)
436 		return false;
437 	return memcmp(ssid_elem->data, ssid, ssid_len) == 0;
438 }
439 
440 static int
441 cfg80211_add_nontrans_list(struct cfg80211_bss *trans_bss,
442 			   struct cfg80211_bss *nontrans_bss)
443 {
444 	const struct element *ssid_elem;
445 	struct cfg80211_bss *bss = NULL;
446 
447 	rcu_read_lock();
448 	ssid_elem = ieee80211_bss_get_elem(nontrans_bss, WLAN_EID_SSID);
449 	if (!ssid_elem) {
450 		rcu_read_unlock();
451 		return -EINVAL;
452 	}
453 
454 	/* check if nontrans_bss is in the list */
455 	list_for_each_entry(bss, &trans_bss->nontrans_list, nontrans_list) {
456 		if (is_bss(bss, nontrans_bss->bssid, ssid_elem->data,
457 			   ssid_elem->datalen)) {
458 			rcu_read_unlock();
459 			return 0;
460 		}
461 	}
462 
463 	rcu_read_unlock();
464 
465 	/*
466 	 * This is a bit weird - it's not on the list, but already on another
467 	 * one! The only way that could happen is if there's some BSSID/SSID
468 	 * shared by multiple APs in their multi-BSSID profiles, potentially
469 	 * with hidden SSID mixed in ... ignore it.
470 	 */
471 	if (!list_empty(&nontrans_bss->nontrans_list))
472 		return -EINVAL;
473 
474 	/* add to the list */
475 	list_add_tail(&nontrans_bss->nontrans_list, &trans_bss->nontrans_list);
476 	return 0;
477 }
478 
479 static void __cfg80211_bss_expire(struct cfg80211_registered_device *rdev,
480 				  unsigned long expire_time)
481 {
482 	struct cfg80211_internal_bss *bss, *tmp;
483 	bool expired = false;
484 
485 	lockdep_assert_held(&rdev->bss_lock);
486 
487 	list_for_each_entry_safe(bss, tmp, &rdev->bss_list, list) {
488 		if (atomic_read(&bss->hold))
489 			continue;
490 		if (!time_after(expire_time, bss->ts))
491 			continue;
492 
493 		if (__cfg80211_unlink_bss(rdev, bss))
494 			expired = true;
495 	}
496 
497 	if (expired)
498 		rdev->bss_generation++;
499 }
500 
501 static bool cfg80211_bss_expire_oldest(struct cfg80211_registered_device *rdev)
502 {
503 	struct cfg80211_internal_bss *bss, *oldest = NULL;
504 	bool ret;
505 
506 	lockdep_assert_held(&rdev->bss_lock);
507 
508 	list_for_each_entry(bss, &rdev->bss_list, list) {
509 		if (atomic_read(&bss->hold))
510 			continue;
511 
512 		if (!list_empty(&bss->hidden_list) &&
513 		    !bss->pub.hidden_beacon_bss)
514 			continue;
515 
516 		if (oldest && time_before(oldest->ts, bss->ts))
517 			continue;
518 		oldest = bss;
519 	}
520 
521 	if (WARN_ON(!oldest))
522 		return false;
523 
524 	/*
525 	 * The callers make sure to increase rdev->bss_generation if anything
526 	 * gets removed (and a new entry added), so there's no need to also do
527 	 * it here.
528 	 */
529 
530 	ret = __cfg80211_unlink_bss(rdev, oldest);
531 	WARN_ON(!ret);
532 	return ret;
533 }
534 
535 static u8 cfg80211_parse_bss_param(u8 data,
536 				   struct cfg80211_colocated_ap *coloc_ap)
537 {
538 	coloc_ap->oct_recommended =
539 		u8_get_bits(data, IEEE80211_RNR_TBTT_PARAMS_OCT_RECOMMENDED);
540 	coloc_ap->same_ssid =
541 		u8_get_bits(data, IEEE80211_RNR_TBTT_PARAMS_SAME_SSID);
542 	coloc_ap->multi_bss =
543 		u8_get_bits(data, IEEE80211_RNR_TBTT_PARAMS_MULTI_BSSID);
544 	coloc_ap->transmitted_bssid =
545 		u8_get_bits(data, IEEE80211_RNR_TBTT_PARAMS_TRANSMITTED_BSSID);
546 	coloc_ap->unsolicited_probe =
547 		u8_get_bits(data, IEEE80211_RNR_TBTT_PARAMS_PROBE_ACTIVE);
548 	coloc_ap->colocated_ess =
549 		u8_get_bits(data, IEEE80211_RNR_TBTT_PARAMS_COLOC_ESS);
550 
551 	return u8_get_bits(data, IEEE80211_RNR_TBTT_PARAMS_COLOC_AP);
552 }
553 
554 static int cfg80211_calc_short_ssid(const struct cfg80211_bss_ies *ies,
555 				    const struct element **elem, u32 *s_ssid)
556 {
557 
558 	*elem = cfg80211_find_elem(WLAN_EID_SSID, ies->data, ies->len);
559 	if (!*elem || (*elem)->datalen > IEEE80211_MAX_SSID_LEN)
560 		return -EINVAL;
561 
562 	*s_ssid = ~crc32_le(~0, (*elem)->data, (*elem)->datalen);
563 	return 0;
564 }
565 
566 static void cfg80211_free_coloc_ap_list(struct list_head *coloc_ap_list)
567 {
568 	struct cfg80211_colocated_ap *ap, *tmp_ap;
569 
570 	list_for_each_entry_safe(ap, tmp_ap, coloc_ap_list, list) {
571 		list_del(&ap->list);
572 		kfree(ap);
573 	}
574 }
575 
576 static int cfg80211_parse_ap_info(struct cfg80211_colocated_ap *entry,
577 				  const u8 *pos, u8 length,
578 				  const struct element *ssid_elem,
579 				  u32 s_ssid_tmp)
580 {
581 	u8 bss_params;
582 
583 	entry->psd_20 = IEEE80211_RNR_TBTT_PARAMS_PSD_RESERVED;
584 
585 	/* The length is already verified by the caller to contain bss_params */
586 	if (length > sizeof(struct ieee80211_tbtt_info_7_8_9)) {
587 		struct ieee80211_tbtt_info_ge_11 *tbtt_info = (void *)pos;
588 
589 		memcpy(entry->bssid, tbtt_info->bssid, ETH_ALEN);
590 		entry->short_ssid = le32_to_cpu(tbtt_info->short_ssid);
591 		entry->short_ssid_valid = true;
592 
593 		bss_params = tbtt_info->bss_params;
594 
595 		/* Ignore disabled links */
596 		if (length >= offsetofend(typeof(*tbtt_info), mld_params)) {
597 			if (le16_get_bits(tbtt_info->mld_params.params,
598 					  IEEE80211_RNR_MLD_PARAMS_DISABLED_LINK))
599 				return -EINVAL;
600 		}
601 
602 		if (length >= offsetofend(struct ieee80211_tbtt_info_ge_11,
603 					  psd_20))
604 			entry->psd_20 = tbtt_info->psd_20;
605 	} else {
606 		struct ieee80211_tbtt_info_7_8_9 *tbtt_info = (void *)pos;
607 
608 		memcpy(entry->bssid, tbtt_info->bssid, ETH_ALEN);
609 
610 		bss_params = tbtt_info->bss_params;
611 
612 		if (length == offsetofend(struct ieee80211_tbtt_info_7_8_9,
613 					  psd_20))
614 			entry->psd_20 = tbtt_info->psd_20;
615 	}
616 
617 	/* ignore entries with invalid BSSID */
618 	if (!is_valid_ether_addr(entry->bssid))
619 		return -EINVAL;
620 
621 	/* skip non colocated APs */
622 	if (!cfg80211_parse_bss_param(bss_params, entry))
623 		return -EINVAL;
624 
625 	/* no information about the short ssid. Consider the entry valid
626 	 * for now. It would later be dropped in case there are explicit
627 	 * SSIDs that need to be matched
628 	 */
629 	if (!entry->same_ssid && !entry->short_ssid_valid)
630 		return 0;
631 
632 	if (entry->same_ssid) {
633 		entry->short_ssid = s_ssid_tmp;
634 		entry->short_ssid_valid = true;
635 
636 		/*
637 		 * This is safe because we validate datalen in
638 		 * cfg80211_parse_colocated_ap(), before calling this
639 		 * function.
640 		 */
641 		memcpy(&entry->ssid, &ssid_elem->data, ssid_elem->datalen);
642 		entry->ssid_len = ssid_elem->datalen;
643 	}
644 
645 	return 0;
646 }
647 
648 static int cfg80211_parse_colocated_ap(const struct cfg80211_bss_ies *ies,
649 				       struct list_head *list)
650 {
651 	struct ieee80211_neighbor_ap_info *ap_info;
652 	const struct element *elem, *ssid_elem;
653 	const u8 *pos, *end;
654 	u32 s_ssid_tmp;
655 	int n_coloc = 0, ret;
656 	LIST_HEAD(ap_list);
657 
658 	ret = cfg80211_calc_short_ssid(ies, &ssid_elem, &s_ssid_tmp);
659 	if (ret)
660 		return 0;
661 
662 	for_each_element_id(elem, WLAN_EID_REDUCED_NEIGHBOR_REPORT,
663 			    ies->data, ies->len) {
664 		pos = elem->data;
665 		end = elem->data + elem->datalen;
666 
667 		/* RNR IE may contain more than one NEIGHBOR_AP_INFO */
668 		while (pos + sizeof(*ap_info) <= end) {
669 			enum nl80211_band band;
670 			int freq;
671 			u8 length, i, count;
672 
673 			ap_info = (void *)pos;
674 			count = u8_get_bits(ap_info->tbtt_info_hdr,
675 					    IEEE80211_AP_INFO_TBTT_HDR_COUNT) + 1;
676 			length = ap_info->tbtt_info_len;
677 
678 			pos += sizeof(*ap_info);
679 
680 			if (!ieee80211_operating_class_to_band(ap_info->op_class,
681 							       &band))
682 				break;
683 
684 			freq = ieee80211_channel_to_frequency(ap_info->channel,
685 							      band);
686 
687 			if (end - pos < count * length)
688 				break;
689 
690 			if (u8_get_bits(ap_info->tbtt_info_hdr,
691 					IEEE80211_AP_INFO_TBTT_HDR_TYPE) !=
692 			    IEEE80211_TBTT_INFO_TYPE_TBTT) {
693 				pos += count * length;
694 				continue;
695 			}
696 
697 			/* TBTT info must include bss param + BSSID +
698 			 * (short SSID or same_ssid bit to be set).
699 			 * ignore other options, and move to the
700 			 * next AP info
701 			 */
702 			if (band != NL80211_BAND_6GHZ ||
703 			    !(length == offsetofend(struct ieee80211_tbtt_info_7_8_9,
704 						    bss_params) ||
705 			      length == sizeof(struct ieee80211_tbtt_info_7_8_9) ||
706 			      length >= offsetofend(struct ieee80211_tbtt_info_ge_11,
707 						    bss_params))) {
708 				pos += count * length;
709 				continue;
710 			}
711 
712 			for (i = 0; i < count; i++) {
713 				struct cfg80211_colocated_ap *entry;
714 
715 				entry = kzalloc(sizeof(*entry) + IEEE80211_MAX_SSID_LEN,
716 						GFP_ATOMIC);
717 
718 				if (!entry)
719 					goto error;
720 
721 				entry->center_freq = freq;
722 
723 				if (!cfg80211_parse_ap_info(entry, pos, length,
724 							    ssid_elem,
725 							    s_ssid_tmp)) {
726 					n_coloc++;
727 					list_add_tail(&entry->list, &ap_list);
728 				} else {
729 					kfree(entry);
730 				}
731 
732 				pos += length;
733 			}
734 		}
735 
736 error:
737 		if (pos != end) {
738 			cfg80211_free_coloc_ap_list(&ap_list);
739 			return 0;
740 		}
741 	}
742 
743 	list_splice_tail(&ap_list, list);
744 	return n_coloc;
745 }
746 
747 static  void cfg80211_scan_req_add_chan(struct cfg80211_scan_request *request,
748 					struct ieee80211_channel *chan,
749 					bool add_to_6ghz)
750 {
751 	int i;
752 	u32 n_channels = request->n_channels;
753 	struct cfg80211_scan_6ghz_params *params =
754 		&request->scan_6ghz_params[request->n_6ghz_params];
755 
756 	for (i = 0; i < n_channels; i++) {
757 		if (request->channels[i] == chan) {
758 			if (add_to_6ghz)
759 				params->channel_idx = i;
760 			return;
761 		}
762 	}
763 
764 	request->channels[n_channels] = chan;
765 	if (add_to_6ghz)
766 		request->scan_6ghz_params[request->n_6ghz_params].channel_idx =
767 			n_channels;
768 
769 	request->n_channels++;
770 }
771 
772 static bool cfg80211_find_ssid_match(struct cfg80211_colocated_ap *ap,
773 				     struct cfg80211_scan_request *request)
774 {
775 	int i;
776 	u32 s_ssid;
777 
778 	for (i = 0; i < request->n_ssids; i++) {
779 		/* wildcard ssid in the scan request */
780 		if (!request->ssids[i].ssid_len) {
781 			if (ap->multi_bss && !ap->transmitted_bssid)
782 				continue;
783 
784 			return true;
785 		}
786 
787 		if (ap->ssid_len &&
788 		    ap->ssid_len == request->ssids[i].ssid_len) {
789 			if (!memcmp(request->ssids[i].ssid, ap->ssid,
790 				    ap->ssid_len))
791 				return true;
792 		} else if (ap->short_ssid_valid) {
793 			s_ssid = ~crc32_le(~0, request->ssids[i].ssid,
794 					   request->ssids[i].ssid_len);
795 
796 			if (ap->short_ssid == s_ssid)
797 				return true;
798 		}
799 	}
800 
801 	return false;
802 }
803 
804 static int cfg80211_scan_6ghz(struct cfg80211_registered_device *rdev)
805 {
806 	u8 i;
807 	struct cfg80211_colocated_ap *ap;
808 	int n_channels, count = 0, err;
809 	struct cfg80211_scan_request *request, *rdev_req = rdev->scan_req;
810 	LIST_HEAD(coloc_ap_list);
811 	bool need_scan_psc = true;
812 	const struct ieee80211_sband_iftype_data *iftd;
813 
814 	rdev_req->scan_6ghz = true;
815 
816 	if (!rdev->wiphy.bands[NL80211_BAND_6GHZ])
817 		return -EOPNOTSUPP;
818 
819 	iftd = ieee80211_get_sband_iftype_data(rdev->wiphy.bands[NL80211_BAND_6GHZ],
820 					       rdev_req->wdev->iftype);
821 	if (!iftd || !iftd->he_cap.has_he)
822 		return -EOPNOTSUPP;
823 
824 	n_channels = rdev->wiphy.bands[NL80211_BAND_6GHZ]->n_channels;
825 
826 	if (rdev_req->flags & NL80211_SCAN_FLAG_COLOCATED_6GHZ) {
827 		struct cfg80211_internal_bss *intbss;
828 
829 		spin_lock_bh(&rdev->bss_lock);
830 		list_for_each_entry(intbss, &rdev->bss_list, list) {
831 			struct cfg80211_bss *res = &intbss->pub;
832 			const struct cfg80211_bss_ies *ies;
833 
834 			ies = rcu_access_pointer(res->ies);
835 			count += cfg80211_parse_colocated_ap(ies,
836 							     &coloc_ap_list);
837 		}
838 		spin_unlock_bh(&rdev->bss_lock);
839 	}
840 
841 	request = kzalloc(struct_size(request, channels, n_channels) +
842 			  sizeof(*request->scan_6ghz_params) * count +
843 			  sizeof(*request->ssids) * rdev_req->n_ssids,
844 			  GFP_KERNEL);
845 	if (!request) {
846 		cfg80211_free_coloc_ap_list(&coloc_ap_list);
847 		return -ENOMEM;
848 	}
849 
850 	*request = *rdev_req;
851 	request->n_channels = 0;
852 	request->scan_6ghz_params =
853 		(void *)&request->channels[n_channels];
854 
855 	/*
856 	 * PSC channels should not be scanned in case of direct scan with 1 SSID
857 	 * and at least one of the reported co-located APs with same SSID
858 	 * indicating that all APs in the same ESS are co-located
859 	 */
860 	if (count && request->n_ssids == 1 && request->ssids[0].ssid_len) {
861 		list_for_each_entry(ap, &coloc_ap_list, list) {
862 			if (ap->colocated_ess &&
863 			    cfg80211_find_ssid_match(ap, request)) {
864 				need_scan_psc = false;
865 				break;
866 			}
867 		}
868 	}
869 
870 	/*
871 	 * add to the scan request the channels that need to be scanned
872 	 * regardless of the collocated APs (PSC channels or all channels
873 	 * in case that NL80211_SCAN_FLAG_COLOCATED_6GHZ is not set)
874 	 */
875 	for (i = 0; i < rdev_req->n_channels; i++) {
876 		if (rdev_req->channels[i]->band == NL80211_BAND_6GHZ &&
877 		    ((need_scan_psc &&
878 		      cfg80211_channel_is_psc(rdev_req->channels[i])) ||
879 		     !(rdev_req->flags & NL80211_SCAN_FLAG_COLOCATED_6GHZ))) {
880 			cfg80211_scan_req_add_chan(request,
881 						   rdev_req->channels[i],
882 						   false);
883 		}
884 	}
885 
886 	if (!(rdev_req->flags & NL80211_SCAN_FLAG_COLOCATED_6GHZ))
887 		goto skip;
888 
889 	list_for_each_entry(ap, &coloc_ap_list, list) {
890 		bool found = false;
891 		struct cfg80211_scan_6ghz_params *scan_6ghz_params =
892 			&request->scan_6ghz_params[request->n_6ghz_params];
893 		struct ieee80211_channel *chan =
894 			ieee80211_get_channel(&rdev->wiphy, ap->center_freq);
895 
896 		if (!chan || chan->flags & IEEE80211_CHAN_DISABLED)
897 			continue;
898 
899 		for (i = 0; i < rdev_req->n_channels; i++) {
900 			if (rdev_req->channels[i] == chan)
901 				found = true;
902 		}
903 
904 		if (!found)
905 			continue;
906 
907 		if (request->n_ssids > 0 &&
908 		    !cfg80211_find_ssid_match(ap, request))
909 			continue;
910 
911 		if (!is_broadcast_ether_addr(request->bssid) &&
912 		    !ether_addr_equal(request->bssid, ap->bssid))
913 			continue;
914 
915 		if (!request->n_ssids && ap->multi_bss && !ap->transmitted_bssid)
916 			continue;
917 
918 		cfg80211_scan_req_add_chan(request, chan, true);
919 		memcpy(scan_6ghz_params->bssid, ap->bssid, ETH_ALEN);
920 		scan_6ghz_params->short_ssid = ap->short_ssid;
921 		scan_6ghz_params->short_ssid_valid = ap->short_ssid_valid;
922 		scan_6ghz_params->unsolicited_probe = ap->unsolicited_probe;
923 		scan_6ghz_params->psd_20 = ap->psd_20;
924 
925 		/*
926 		 * If a PSC channel is added to the scan and 'need_scan_psc' is
927 		 * set to false, then all the APs that the scan logic is
928 		 * interested with on the channel are collocated and thus there
929 		 * is no need to perform the initial PSC channel listen.
930 		 */
931 		if (cfg80211_channel_is_psc(chan) && !need_scan_psc)
932 			scan_6ghz_params->psc_no_listen = true;
933 
934 		request->n_6ghz_params++;
935 	}
936 
937 skip:
938 	cfg80211_free_coloc_ap_list(&coloc_ap_list);
939 
940 	if (request->n_channels) {
941 		struct cfg80211_scan_request *old = rdev->int_scan_req;
942 		rdev->int_scan_req = request;
943 
944 		/*
945 		 * Add the ssids from the parent scan request to the new scan
946 		 * request, so the driver would be able to use them in its
947 		 * probe requests to discover hidden APs on PSC channels.
948 		 */
949 		request->ssids = (void *)&request->channels[request->n_channels];
950 		request->n_ssids = rdev_req->n_ssids;
951 		memcpy(request->ssids, rdev_req->ssids, sizeof(*request->ssids) *
952 		       request->n_ssids);
953 
954 		/*
955 		 * If this scan follows a previous scan, save the scan start
956 		 * info from the first part of the scan
957 		 */
958 		if (old)
959 			rdev->int_scan_req->info = old->info;
960 
961 		err = rdev_scan(rdev, request);
962 		if (err) {
963 			rdev->int_scan_req = old;
964 			kfree(request);
965 		} else {
966 			kfree(old);
967 		}
968 
969 		return err;
970 	}
971 
972 	kfree(request);
973 	return -EINVAL;
974 }
975 
976 int cfg80211_scan(struct cfg80211_registered_device *rdev)
977 {
978 	struct cfg80211_scan_request *request;
979 	struct cfg80211_scan_request *rdev_req = rdev->scan_req;
980 	u32 n_channels = 0, idx, i;
981 
982 	if (!(rdev->wiphy.flags & WIPHY_FLAG_SPLIT_SCAN_6GHZ))
983 		return rdev_scan(rdev, rdev_req);
984 
985 	for (i = 0; i < rdev_req->n_channels; i++) {
986 		if (rdev_req->channels[i]->band != NL80211_BAND_6GHZ)
987 			n_channels++;
988 	}
989 
990 	if (!n_channels)
991 		return cfg80211_scan_6ghz(rdev);
992 
993 	request = kzalloc(struct_size(request, channels, n_channels),
994 			  GFP_KERNEL);
995 	if (!request)
996 		return -ENOMEM;
997 
998 	*request = *rdev_req;
999 	request->n_channels = n_channels;
1000 
1001 	for (i = idx = 0; i < rdev_req->n_channels; i++) {
1002 		if (rdev_req->channels[i]->band != NL80211_BAND_6GHZ)
1003 			request->channels[idx++] = rdev_req->channels[i];
1004 	}
1005 
1006 	rdev_req->scan_6ghz = false;
1007 	rdev->int_scan_req = request;
1008 	return rdev_scan(rdev, request);
1009 }
1010 
1011 void ___cfg80211_scan_done(struct cfg80211_registered_device *rdev,
1012 			   bool send_message)
1013 {
1014 	struct cfg80211_scan_request *request, *rdev_req;
1015 	struct wireless_dev *wdev;
1016 	struct sk_buff *msg;
1017 #ifdef CONFIG_CFG80211_WEXT
1018 	union iwreq_data wrqu;
1019 #endif
1020 
1021 	lockdep_assert_held(&rdev->wiphy.mtx);
1022 
1023 	if (rdev->scan_msg) {
1024 		nl80211_send_scan_msg(rdev, rdev->scan_msg);
1025 		rdev->scan_msg = NULL;
1026 		return;
1027 	}
1028 
1029 	rdev_req = rdev->scan_req;
1030 	if (!rdev_req)
1031 		return;
1032 
1033 	wdev = rdev_req->wdev;
1034 	request = rdev->int_scan_req ? rdev->int_scan_req : rdev_req;
1035 
1036 	if (wdev_running(wdev) &&
1037 	    (rdev->wiphy.flags & WIPHY_FLAG_SPLIT_SCAN_6GHZ) &&
1038 	    !rdev_req->scan_6ghz && !request->info.aborted &&
1039 	    !cfg80211_scan_6ghz(rdev))
1040 		return;
1041 
1042 	/*
1043 	 * This must be before sending the other events!
1044 	 * Otherwise, wpa_supplicant gets completely confused with
1045 	 * wext events.
1046 	 */
1047 	if (wdev->netdev)
1048 		cfg80211_sme_scan_done(wdev->netdev);
1049 
1050 	if (!request->info.aborted &&
1051 	    request->flags & NL80211_SCAN_FLAG_FLUSH) {
1052 		/* flush entries from previous scans */
1053 		spin_lock_bh(&rdev->bss_lock);
1054 		__cfg80211_bss_expire(rdev, request->scan_start);
1055 		spin_unlock_bh(&rdev->bss_lock);
1056 	}
1057 
1058 	msg = nl80211_build_scan_msg(rdev, wdev, request->info.aborted);
1059 
1060 #ifdef CONFIG_CFG80211_WEXT
1061 	if (wdev->netdev && !request->info.aborted) {
1062 		memset(&wrqu, 0, sizeof(wrqu));
1063 
1064 		wireless_send_event(wdev->netdev, SIOCGIWSCAN, &wrqu, NULL);
1065 	}
1066 #endif
1067 
1068 	dev_put(wdev->netdev);
1069 
1070 	kfree(rdev->int_scan_req);
1071 	rdev->int_scan_req = NULL;
1072 
1073 	kfree(rdev->scan_req);
1074 	rdev->scan_req = NULL;
1075 
1076 	if (!send_message)
1077 		rdev->scan_msg = msg;
1078 	else
1079 		nl80211_send_scan_msg(rdev, msg);
1080 }
1081 
1082 void __cfg80211_scan_done(struct wiphy *wiphy, struct wiphy_work *wk)
1083 {
1084 	___cfg80211_scan_done(wiphy_to_rdev(wiphy), true);
1085 }
1086 
1087 void cfg80211_scan_done(struct cfg80211_scan_request *request,
1088 			struct cfg80211_scan_info *info)
1089 {
1090 	struct cfg80211_scan_info old_info = request->info;
1091 
1092 	trace_cfg80211_scan_done(request, info);
1093 	WARN_ON(request != wiphy_to_rdev(request->wiphy)->scan_req &&
1094 		request != wiphy_to_rdev(request->wiphy)->int_scan_req);
1095 
1096 	request->info = *info;
1097 
1098 	/*
1099 	 * In case the scan is split, the scan_start_tsf and tsf_bssid should
1100 	 * be of the first part. In such a case old_info.scan_start_tsf should
1101 	 * be non zero.
1102 	 */
1103 	if (request->scan_6ghz && old_info.scan_start_tsf) {
1104 		request->info.scan_start_tsf = old_info.scan_start_tsf;
1105 		memcpy(request->info.tsf_bssid, old_info.tsf_bssid,
1106 		       sizeof(request->info.tsf_bssid));
1107 	}
1108 
1109 	request->notified = true;
1110 	wiphy_work_queue(request->wiphy,
1111 			 &wiphy_to_rdev(request->wiphy)->scan_done_wk);
1112 }
1113 EXPORT_SYMBOL(cfg80211_scan_done);
1114 
1115 void cfg80211_add_sched_scan_req(struct cfg80211_registered_device *rdev,
1116 				 struct cfg80211_sched_scan_request *req)
1117 {
1118 	lockdep_assert_held(&rdev->wiphy.mtx);
1119 
1120 	list_add_rcu(&req->list, &rdev->sched_scan_req_list);
1121 }
1122 
1123 static void cfg80211_del_sched_scan_req(struct cfg80211_registered_device *rdev,
1124 					struct cfg80211_sched_scan_request *req)
1125 {
1126 	lockdep_assert_held(&rdev->wiphy.mtx);
1127 
1128 	list_del_rcu(&req->list);
1129 	kfree_rcu(req, rcu_head);
1130 }
1131 
1132 static struct cfg80211_sched_scan_request *
1133 cfg80211_find_sched_scan_req(struct cfg80211_registered_device *rdev, u64 reqid)
1134 {
1135 	struct cfg80211_sched_scan_request *pos;
1136 
1137 	list_for_each_entry_rcu(pos, &rdev->sched_scan_req_list, list,
1138 				lockdep_is_held(&rdev->wiphy.mtx)) {
1139 		if (pos->reqid == reqid)
1140 			return pos;
1141 	}
1142 	return NULL;
1143 }
1144 
1145 /*
1146  * Determines if a scheduled scan request can be handled. When a legacy
1147  * scheduled scan is running no other scheduled scan is allowed regardless
1148  * whether the request is for legacy or multi-support scan. When a multi-support
1149  * scheduled scan is running a request for legacy scan is not allowed. In this
1150  * case a request for multi-support scan can be handled if resources are
1151  * available, ie. struct wiphy::max_sched_scan_reqs limit is not yet reached.
1152  */
1153 int cfg80211_sched_scan_req_possible(struct cfg80211_registered_device *rdev,
1154 				     bool want_multi)
1155 {
1156 	struct cfg80211_sched_scan_request *pos;
1157 	int i = 0;
1158 
1159 	list_for_each_entry(pos, &rdev->sched_scan_req_list, list) {
1160 		/* request id zero means legacy in progress */
1161 		if (!i && !pos->reqid)
1162 			return -EINPROGRESS;
1163 		i++;
1164 	}
1165 
1166 	if (i) {
1167 		/* no legacy allowed when multi request(s) are active */
1168 		if (!want_multi)
1169 			return -EINPROGRESS;
1170 
1171 		/* resource limit reached */
1172 		if (i == rdev->wiphy.max_sched_scan_reqs)
1173 			return -ENOSPC;
1174 	}
1175 	return 0;
1176 }
1177 
1178 void cfg80211_sched_scan_results_wk(struct work_struct *work)
1179 {
1180 	struct cfg80211_registered_device *rdev;
1181 	struct cfg80211_sched_scan_request *req, *tmp;
1182 
1183 	rdev = container_of(work, struct cfg80211_registered_device,
1184 			   sched_scan_res_wk);
1185 
1186 	wiphy_lock(&rdev->wiphy);
1187 	list_for_each_entry_safe(req, tmp, &rdev->sched_scan_req_list, list) {
1188 		if (req->report_results) {
1189 			req->report_results = false;
1190 			if (req->flags & NL80211_SCAN_FLAG_FLUSH) {
1191 				/* flush entries from previous scans */
1192 				spin_lock_bh(&rdev->bss_lock);
1193 				__cfg80211_bss_expire(rdev, req->scan_start);
1194 				spin_unlock_bh(&rdev->bss_lock);
1195 				req->scan_start = jiffies;
1196 			}
1197 			nl80211_send_sched_scan(req,
1198 						NL80211_CMD_SCHED_SCAN_RESULTS);
1199 		}
1200 	}
1201 	wiphy_unlock(&rdev->wiphy);
1202 }
1203 
1204 void cfg80211_sched_scan_results(struct wiphy *wiphy, u64 reqid)
1205 {
1206 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1207 	struct cfg80211_sched_scan_request *request;
1208 
1209 	trace_cfg80211_sched_scan_results(wiphy, reqid);
1210 	/* ignore if we're not scanning */
1211 
1212 	rcu_read_lock();
1213 	request = cfg80211_find_sched_scan_req(rdev, reqid);
1214 	if (request) {
1215 		request->report_results = true;
1216 		queue_work(cfg80211_wq, &rdev->sched_scan_res_wk);
1217 	}
1218 	rcu_read_unlock();
1219 }
1220 EXPORT_SYMBOL(cfg80211_sched_scan_results);
1221 
1222 void cfg80211_sched_scan_stopped_locked(struct wiphy *wiphy, u64 reqid)
1223 {
1224 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1225 
1226 	lockdep_assert_held(&wiphy->mtx);
1227 
1228 	trace_cfg80211_sched_scan_stopped(wiphy, reqid);
1229 
1230 	__cfg80211_stop_sched_scan(rdev, reqid, true);
1231 }
1232 EXPORT_SYMBOL(cfg80211_sched_scan_stopped_locked);
1233 
1234 void cfg80211_sched_scan_stopped(struct wiphy *wiphy, u64 reqid)
1235 {
1236 	wiphy_lock(wiphy);
1237 	cfg80211_sched_scan_stopped_locked(wiphy, reqid);
1238 	wiphy_unlock(wiphy);
1239 }
1240 EXPORT_SYMBOL(cfg80211_sched_scan_stopped);
1241 
1242 int cfg80211_stop_sched_scan_req(struct cfg80211_registered_device *rdev,
1243 				 struct cfg80211_sched_scan_request *req,
1244 				 bool driver_initiated)
1245 {
1246 	lockdep_assert_held(&rdev->wiphy.mtx);
1247 
1248 	if (!driver_initiated) {
1249 		int err = rdev_sched_scan_stop(rdev, req->dev, req->reqid);
1250 		if (err)
1251 			return err;
1252 	}
1253 
1254 	nl80211_send_sched_scan(req, NL80211_CMD_SCHED_SCAN_STOPPED);
1255 
1256 	cfg80211_del_sched_scan_req(rdev, req);
1257 
1258 	return 0;
1259 }
1260 
1261 int __cfg80211_stop_sched_scan(struct cfg80211_registered_device *rdev,
1262 			       u64 reqid, bool driver_initiated)
1263 {
1264 	struct cfg80211_sched_scan_request *sched_scan_req;
1265 
1266 	lockdep_assert_held(&rdev->wiphy.mtx);
1267 
1268 	sched_scan_req = cfg80211_find_sched_scan_req(rdev, reqid);
1269 	if (!sched_scan_req)
1270 		return -ENOENT;
1271 
1272 	return cfg80211_stop_sched_scan_req(rdev, sched_scan_req,
1273 					    driver_initiated);
1274 }
1275 
1276 void cfg80211_bss_age(struct cfg80211_registered_device *rdev,
1277                       unsigned long age_secs)
1278 {
1279 	struct cfg80211_internal_bss *bss;
1280 	unsigned long age_jiffies = msecs_to_jiffies(age_secs * MSEC_PER_SEC);
1281 
1282 	spin_lock_bh(&rdev->bss_lock);
1283 	list_for_each_entry(bss, &rdev->bss_list, list)
1284 		bss->ts -= age_jiffies;
1285 	spin_unlock_bh(&rdev->bss_lock);
1286 }
1287 
1288 void cfg80211_bss_expire(struct cfg80211_registered_device *rdev)
1289 {
1290 	__cfg80211_bss_expire(rdev, jiffies - IEEE80211_SCAN_RESULT_EXPIRE);
1291 }
1292 
1293 void cfg80211_bss_flush(struct wiphy *wiphy)
1294 {
1295 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1296 
1297 	spin_lock_bh(&rdev->bss_lock);
1298 	__cfg80211_bss_expire(rdev, jiffies);
1299 	spin_unlock_bh(&rdev->bss_lock);
1300 }
1301 EXPORT_SYMBOL(cfg80211_bss_flush);
1302 
1303 const struct element *
1304 cfg80211_find_elem_match(u8 eid, const u8 *ies, unsigned int len,
1305 			 const u8 *match, unsigned int match_len,
1306 			 unsigned int match_offset)
1307 {
1308 	const struct element *elem;
1309 
1310 	for_each_element_id(elem, eid, ies, len) {
1311 		if (elem->datalen >= match_offset + match_len &&
1312 		    !memcmp(elem->data + match_offset, match, match_len))
1313 			return elem;
1314 	}
1315 
1316 	return NULL;
1317 }
1318 EXPORT_SYMBOL(cfg80211_find_elem_match);
1319 
1320 const struct element *cfg80211_find_vendor_elem(unsigned int oui, int oui_type,
1321 						const u8 *ies,
1322 						unsigned int len)
1323 {
1324 	const struct element *elem;
1325 	u8 match[] = { oui >> 16, oui >> 8, oui, oui_type };
1326 	int match_len = (oui_type < 0) ? 3 : sizeof(match);
1327 
1328 	if (WARN_ON(oui_type > 0xff))
1329 		return NULL;
1330 
1331 	elem = cfg80211_find_elem_match(WLAN_EID_VENDOR_SPECIFIC, ies, len,
1332 					match, match_len, 0);
1333 
1334 	if (!elem || elem->datalen < 4)
1335 		return NULL;
1336 
1337 	return elem;
1338 }
1339 EXPORT_SYMBOL(cfg80211_find_vendor_elem);
1340 
1341 /**
1342  * enum bss_compare_mode - BSS compare mode
1343  * @BSS_CMP_REGULAR: regular compare mode (for insertion and normal find)
1344  * @BSS_CMP_HIDE_ZLEN: find hidden SSID with zero-length mode
1345  * @BSS_CMP_HIDE_NUL: find hidden SSID with NUL-ed out mode
1346  */
1347 enum bss_compare_mode {
1348 	BSS_CMP_REGULAR,
1349 	BSS_CMP_HIDE_ZLEN,
1350 	BSS_CMP_HIDE_NUL,
1351 };
1352 
1353 static int cmp_bss(struct cfg80211_bss *a,
1354 		   struct cfg80211_bss *b,
1355 		   enum bss_compare_mode mode)
1356 {
1357 	const struct cfg80211_bss_ies *a_ies, *b_ies;
1358 	const u8 *ie1 = NULL;
1359 	const u8 *ie2 = NULL;
1360 	int i, r;
1361 
1362 	if (a->channel != b->channel)
1363 		return (b->channel->center_freq * 1000 + b->channel->freq_offset) -
1364 		       (a->channel->center_freq * 1000 + a->channel->freq_offset);
1365 
1366 	a_ies = rcu_access_pointer(a->ies);
1367 	if (!a_ies)
1368 		return -1;
1369 	b_ies = rcu_access_pointer(b->ies);
1370 	if (!b_ies)
1371 		return 1;
1372 
1373 	if (WLAN_CAPABILITY_IS_STA_BSS(a->capability))
1374 		ie1 = cfg80211_find_ie(WLAN_EID_MESH_ID,
1375 				       a_ies->data, a_ies->len);
1376 	if (WLAN_CAPABILITY_IS_STA_BSS(b->capability))
1377 		ie2 = cfg80211_find_ie(WLAN_EID_MESH_ID,
1378 				       b_ies->data, b_ies->len);
1379 	if (ie1 && ie2) {
1380 		int mesh_id_cmp;
1381 
1382 		if (ie1[1] == ie2[1])
1383 			mesh_id_cmp = memcmp(ie1 + 2, ie2 + 2, ie1[1]);
1384 		else
1385 			mesh_id_cmp = ie2[1] - ie1[1];
1386 
1387 		ie1 = cfg80211_find_ie(WLAN_EID_MESH_CONFIG,
1388 				       a_ies->data, a_ies->len);
1389 		ie2 = cfg80211_find_ie(WLAN_EID_MESH_CONFIG,
1390 				       b_ies->data, b_ies->len);
1391 		if (ie1 && ie2) {
1392 			if (mesh_id_cmp)
1393 				return mesh_id_cmp;
1394 			if (ie1[1] != ie2[1])
1395 				return ie2[1] - ie1[1];
1396 			return memcmp(ie1 + 2, ie2 + 2, ie1[1]);
1397 		}
1398 	}
1399 
1400 	r = memcmp(a->bssid, b->bssid, sizeof(a->bssid));
1401 	if (r)
1402 		return r;
1403 
1404 	ie1 = cfg80211_find_ie(WLAN_EID_SSID, a_ies->data, a_ies->len);
1405 	ie2 = cfg80211_find_ie(WLAN_EID_SSID, b_ies->data, b_ies->len);
1406 
1407 	if (!ie1 && !ie2)
1408 		return 0;
1409 
1410 	/*
1411 	 * Note that with "hide_ssid", the function returns a match if
1412 	 * the already-present BSS ("b") is a hidden SSID beacon for
1413 	 * the new BSS ("a").
1414 	 */
1415 
1416 	/* sort missing IE before (left of) present IE */
1417 	if (!ie1)
1418 		return -1;
1419 	if (!ie2)
1420 		return 1;
1421 
1422 	switch (mode) {
1423 	case BSS_CMP_HIDE_ZLEN:
1424 		/*
1425 		 * In ZLEN mode we assume the BSS entry we're
1426 		 * looking for has a zero-length SSID. So if
1427 		 * the one we're looking at right now has that,
1428 		 * return 0. Otherwise, return the difference
1429 		 * in length, but since we're looking for the
1430 		 * 0-length it's really equivalent to returning
1431 		 * the length of the one we're looking at.
1432 		 *
1433 		 * No content comparison is needed as we assume
1434 		 * the content length is zero.
1435 		 */
1436 		return ie2[1];
1437 	case BSS_CMP_REGULAR:
1438 	default:
1439 		/* sort by length first, then by contents */
1440 		if (ie1[1] != ie2[1])
1441 			return ie2[1] - ie1[1];
1442 		return memcmp(ie1 + 2, ie2 + 2, ie1[1]);
1443 	case BSS_CMP_HIDE_NUL:
1444 		if (ie1[1] != ie2[1])
1445 			return ie2[1] - ie1[1];
1446 		/* this is equivalent to memcmp(zeroes, ie2 + 2, len) */
1447 		for (i = 0; i < ie2[1]; i++)
1448 			if (ie2[i + 2])
1449 				return -1;
1450 		return 0;
1451 	}
1452 }
1453 
1454 static bool cfg80211_bss_type_match(u16 capability,
1455 				    enum nl80211_band band,
1456 				    enum ieee80211_bss_type bss_type)
1457 {
1458 	bool ret = true;
1459 	u16 mask, val;
1460 
1461 	if (bss_type == IEEE80211_BSS_TYPE_ANY)
1462 		return ret;
1463 
1464 	if (band == NL80211_BAND_60GHZ) {
1465 		mask = WLAN_CAPABILITY_DMG_TYPE_MASK;
1466 		switch (bss_type) {
1467 		case IEEE80211_BSS_TYPE_ESS:
1468 			val = WLAN_CAPABILITY_DMG_TYPE_AP;
1469 			break;
1470 		case IEEE80211_BSS_TYPE_PBSS:
1471 			val = WLAN_CAPABILITY_DMG_TYPE_PBSS;
1472 			break;
1473 		case IEEE80211_BSS_TYPE_IBSS:
1474 			val = WLAN_CAPABILITY_DMG_TYPE_IBSS;
1475 			break;
1476 		default:
1477 			return false;
1478 		}
1479 	} else {
1480 		mask = WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS;
1481 		switch (bss_type) {
1482 		case IEEE80211_BSS_TYPE_ESS:
1483 			val = WLAN_CAPABILITY_ESS;
1484 			break;
1485 		case IEEE80211_BSS_TYPE_IBSS:
1486 			val = WLAN_CAPABILITY_IBSS;
1487 			break;
1488 		case IEEE80211_BSS_TYPE_MBSS:
1489 			val = 0;
1490 			break;
1491 		default:
1492 			return false;
1493 		}
1494 	}
1495 
1496 	ret = ((capability & mask) == val);
1497 	return ret;
1498 }
1499 
1500 /* Returned bss is reference counted and must be cleaned up appropriately. */
1501 struct cfg80211_bss *cfg80211_get_bss(struct wiphy *wiphy,
1502 				      struct ieee80211_channel *channel,
1503 				      const u8 *bssid,
1504 				      const u8 *ssid, size_t ssid_len,
1505 				      enum ieee80211_bss_type bss_type,
1506 				      enum ieee80211_privacy privacy)
1507 {
1508 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1509 	struct cfg80211_internal_bss *bss, *res = NULL;
1510 	unsigned long now = jiffies;
1511 	int bss_privacy;
1512 
1513 	trace_cfg80211_get_bss(wiphy, channel, bssid, ssid, ssid_len, bss_type,
1514 			       privacy);
1515 
1516 	spin_lock_bh(&rdev->bss_lock);
1517 
1518 	list_for_each_entry(bss, &rdev->bss_list, list) {
1519 		if (!cfg80211_bss_type_match(bss->pub.capability,
1520 					     bss->pub.channel->band, bss_type))
1521 			continue;
1522 
1523 		bss_privacy = (bss->pub.capability & WLAN_CAPABILITY_PRIVACY);
1524 		if ((privacy == IEEE80211_PRIVACY_ON && !bss_privacy) ||
1525 		    (privacy == IEEE80211_PRIVACY_OFF && bss_privacy))
1526 			continue;
1527 		if (channel && bss->pub.channel != channel)
1528 			continue;
1529 		if (!is_valid_ether_addr(bss->pub.bssid))
1530 			continue;
1531 		/* Don't get expired BSS structs */
1532 		if (time_after(now, bss->ts + IEEE80211_SCAN_RESULT_EXPIRE) &&
1533 		    !atomic_read(&bss->hold))
1534 			continue;
1535 		if (is_bss(&bss->pub, bssid, ssid, ssid_len)) {
1536 			res = bss;
1537 			bss_ref_get(rdev, res);
1538 			break;
1539 		}
1540 	}
1541 
1542 	spin_unlock_bh(&rdev->bss_lock);
1543 	if (!res)
1544 		return NULL;
1545 	trace_cfg80211_return_bss(&res->pub);
1546 	return &res->pub;
1547 }
1548 EXPORT_SYMBOL(cfg80211_get_bss);
1549 
1550 static void rb_insert_bss(struct cfg80211_registered_device *rdev,
1551 			  struct cfg80211_internal_bss *bss)
1552 {
1553 	struct rb_node **p = &rdev->bss_tree.rb_node;
1554 	struct rb_node *parent = NULL;
1555 	struct cfg80211_internal_bss *tbss;
1556 	int cmp;
1557 
1558 	while (*p) {
1559 		parent = *p;
1560 		tbss = rb_entry(parent, struct cfg80211_internal_bss, rbn);
1561 
1562 		cmp = cmp_bss(&bss->pub, &tbss->pub, BSS_CMP_REGULAR);
1563 
1564 		if (WARN_ON(!cmp)) {
1565 			/* will sort of leak this BSS */
1566 			return;
1567 		}
1568 
1569 		if (cmp < 0)
1570 			p = &(*p)->rb_left;
1571 		else
1572 			p = &(*p)->rb_right;
1573 	}
1574 
1575 	rb_link_node(&bss->rbn, parent, p);
1576 	rb_insert_color(&bss->rbn, &rdev->bss_tree);
1577 }
1578 
1579 static struct cfg80211_internal_bss *
1580 rb_find_bss(struct cfg80211_registered_device *rdev,
1581 	    struct cfg80211_internal_bss *res,
1582 	    enum bss_compare_mode mode)
1583 {
1584 	struct rb_node *n = rdev->bss_tree.rb_node;
1585 	struct cfg80211_internal_bss *bss;
1586 	int r;
1587 
1588 	while (n) {
1589 		bss = rb_entry(n, struct cfg80211_internal_bss, rbn);
1590 		r = cmp_bss(&res->pub, &bss->pub, mode);
1591 
1592 		if (r == 0)
1593 			return bss;
1594 		else if (r < 0)
1595 			n = n->rb_left;
1596 		else
1597 			n = n->rb_right;
1598 	}
1599 
1600 	return NULL;
1601 }
1602 
1603 static bool cfg80211_combine_bsses(struct cfg80211_registered_device *rdev,
1604 				   struct cfg80211_internal_bss *new)
1605 {
1606 	const struct cfg80211_bss_ies *ies;
1607 	struct cfg80211_internal_bss *bss;
1608 	const u8 *ie;
1609 	int i, ssidlen;
1610 	u8 fold = 0;
1611 	u32 n_entries = 0;
1612 
1613 	ies = rcu_access_pointer(new->pub.beacon_ies);
1614 	if (WARN_ON(!ies))
1615 		return false;
1616 
1617 	ie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len);
1618 	if (!ie) {
1619 		/* nothing to do */
1620 		return true;
1621 	}
1622 
1623 	ssidlen = ie[1];
1624 	for (i = 0; i < ssidlen; i++)
1625 		fold |= ie[2 + i];
1626 
1627 	if (fold) {
1628 		/* not a hidden SSID */
1629 		return true;
1630 	}
1631 
1632 	/* This is the bad part ... */
1633 
1634 	list_for_each_entry(bss, &rdev->bss_list, list) {
1635 		/*
1636 		 * we're iterating all the entries anyway, so take the
1637 		 * opportunity to validate the list length accounting
1638 		 */
1639 		n_entries++;
1640 
1641 		if (!ether_addr_equal(bss->pub.bssid, new->pub.bssid))
1642 			continue;
1643 		if (bss->pub.channel != new->pub.channel)
1644 			continue;
1645 		if (bss->pub.scan_width != new->pub.scan_width)
1646 			continue;
1647 		if (rcu_access_pointer(bss->pub.beacon_ies))
1648 			continue;
1649 		ies = rcu_access_pointer(bss->pub.ies);
1650 		if (!ies)
1651 			continue;
1652 		ie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len);
1653 		if (!ie)
1654 			continue;
1655 		if (ssidlen && ie[1] != ssidlen)
1656 			continue;
1657 		if (WARN_ON_ONCE(bss->pub.hidden_beacon_bss))
1658 			continue;
1659 		if (WARN_ON_ONCE(!list_empty(&bss->hidden_list)))
1660 			list_del(&bss->hidden_list);
1661 		/* combine them */
1662 		list_add(&bss->hidden_list, &new->hidden_list);
1663 		bss->pub.hidden_beacon_bss = &new->pub;
1664 		new->refcount += bss->refcount;
1665 		rcu_assign_pointer(bss->pub.beacon_ies,
1666 				   new->pub.beacon_ies);
1667 	}
1668 
1669 	WARN_ONCE(n_entries != rdev->bss_entries,
1670 		  "rdev bss entries[%d]/list[len:%d] corruption\n",
1671 		  rdev->bss_entries, n_entries);
1672 
1673 	return true;
1674 }
1675 
1676 static void cfg80211_update_hidden_bsses(struct cfg80211_internal_bss *known,
1677 					 const struct cfg80211_bss_ies *new_ies,
1678 					 const struct cfg80211_bss_ies *old_ies)
1679 {
1680 	struct cfg80211_internal_bss *bss;
1681 
1682 	/* Assign beacon IEs to all sub entries */
1683 	list_for_each_entry(bss, &known->hidden_list, hidden_list) {
1684 		const struct cfg80211_bss_ies *ies;
1685 
1686 		ies = rcu_access_pointer(bss->pub.beacon_ies);
1687 		WARN_ON(ies != old_ies);
1688 
1689 		rcu_assign_pointer(bss->pub.beacon_ies, new_ies);
1690 	}
1691 }
1692 
1693 static bool
1694 cfg80211_update_known_bss(struct cfg80211_registered_device *rdev,
1695 			  struct cfg80211_internal_bss *known,
1696 			  struct cfg80211_internal_bss *new,
1697 			  bool signal_valid)
1698 {
1699 	lockdep_assert_held(&rdev->bss_lock);
1700 
1701 	/* Update IEs */
1702 	if (rcu_access_pointer(new->pub.proberesp_ies)) {
1703 		const struct cfg80211_bss_ies *old;
1704 
1705 		old = rcu_access_pointer(known->pub.proberesp_ies);
1706 
1707 		rcu_assign_pointer(known->pub.proberesp_ies,
1708 				   new->pub.proberesp_ies);
1709 		/* Override possible earlier Beacon frame IEs */
1710 		rcu_assign_pointer(known->pub.ies,
1711 				   new->pub.proberesp_ies);
1712 		if (old)
1713 			kfree_rcu((struct cfg80211_bss_ies *)old, rcu_head);
1714 	} else if (rcu_access_pointer(new->pub.beacon_ies)) {
1715 		const struct cfg80211_bss_ies *old;
1716 
1717 		if (known->pub.hidden_beacon_bss &&
1718 		    !list_empty(&known->hidden_list)) {
1719 			const struct cfg80211_bss_ies *f;
1720 
1721 			/* The known BSS struct is one of the probe
1722 			 * response members of a group, but we're
1723 			 * receiving a beacon (beacon_ies in the new
1724 			 * bss is used). This can only mean that the
1725 			 * AP changed its beacon from not having an
1726 			 * SSID to showing it, which is confusing so
1727 			 * drop this information.
1728 			 */
1729 
1730 			f = rcu_access_pointer(new->pub.beacon_ies);
1731 			kfree_rcu((struct cfg80211_bss_ies *)f, rcu_head);
1732 			return false;
1733 		}
1734 
1735 		old = rcu_access_pointer(known->pub.beacon_ies);
1736 
1737 		rcu_assign_pointer(known->pub.beacon_ies, new->pub.beacon_ies);
1738 
1739 		/* Override IEs if they were from a beacon before */
1740 		if (old == rcu_access_pointer(known->pub.ies))
1741 			rcu_assign_pointer(known->pub.ies, new->pub.beacon_ies);
1742 
1743 		cfg80211_update_hidden_bsses(known,
1744 					     rcu_access_pointer(new->pub.beacon_ies),
1745 					     old);
1746 
1747 		if (old)
1748 			kfree_rcu((struct cfg80211_bss_ies *)old, rcu_head);
1749 	}
1750 
1751 	known->pub.beacon_interval = new->pub.beacon_interval;
1752 
1753 	/* don't update the signal if beacon was heard on
1754 	 * adjacent channel.
1755 	 */
1756 	if (signal_valid)
1757 		known->pub.signal = new->pub.signal;
1758 	known->pub.capability = new->pub.capability;
1759 	known->ts = new->ts;
1760 	known->ts_boottime = new->ts_boottime;
1761 	known->parent_tsf = new->parent_tsf;
1762 	known->pub.chains = new->pub.chains;
1763 	memcpy(known->pub.chain_signal, new->pub.chain_signal,
1764 	       IEEE80211_MAX_CHAINS);
1765 	ether_addr_copy(known->parent_bssid, new->parent_bssid);
1766 	known->pub.max_bssid_indicator = new->pub.max_bssid_indicator;
1767 	known->pub.bssid_index = new->pub.bssid_index;
1768 
1769 	return true;
1770 }
1771 
1772 /* Returned bss is reference counted and must be cleaned up appropriately. */
1773 static struct cfg80211_internal_bss *
1774 __cfg80211_bss_update(struct cfg80211_registered_device *rdev,
1775 		      struct cfg80211_internal_bss *tmp,
1776 		      bool signal_valid, unsigned long ts)
1777 {
1778 	struct cfg80211_internal_bss *found = NULL;
1779 
1780 	if (WARN_ON(!tmp->pub.channel))
1781 		return NULL;
1782 
1783 	tmp->ts = ts;
1784 
1785 	if (WARN_ON(!rcu_access_pointer(tmp->pub.ies))) {
1786 		return NULL;
1787 	}
1788 
1789 	found = rb_find_bss(rdev, tmp, BSS_CMP_REGULAR);
1790 
1791 	if (found) {
1792 		if (!cfg80211_update_known_bss(rdev, found, tmp, signal_valid))
1793 			return NULL;
1794 	} else {
1795 		struct cfg80211_internal_bss *new;
1796 		struct cfg80211_internal_bss *hidden;
1797 		struct cfg80211_bss_ies *ies;
1798 
1799 		/*
1800 		 * create a copy -- the "res" variable that is passed in
1801 		 * is allocated on the stack since it's not needed in the
1802 		 * more common case of an update
1803 		 */
1804 		new = kzalloc(sizeof(*new) + rdev->wiphy.bss_priv_size,
1805 			      GFP_ATOMIC);
1806 		if (!new) {
1807 			ies = (void *)rcu_dereference(tmp->pub.beacon_ies);
1808 			if (ies)
1809 				kfree_rcu(ies, rcu_head);
1810 			ies = (void *)rcu_dereference(tmp->pub.proberesp_ies);
1811 			if (ies)
1812 				kfree_rcu(ies, rcu_head);
1813 			return NULL;
1814 		}
1815 		memcpy(new, tmp, sizeof(*new));
1816 		new->refcount = 1;
1817 		INIT_LIST_HEAD(&new->hidden_list);
1818 		INIT_LIST_HEAD(&new->pub.nontrans_list);
1819 		/* we'll set this later if it was non-NULL */
1820 		new->pub.transmitted_bss = NULL;
1821 
1822 		if (rcu_access_pointer(tmp->pub.proberesp_ies)) {
1823 			hidden = rb_find_bss(rdev, tmp, BSS_CMP_HIDE_ZLEN);
1824 			if (!hidden)
1825 				hidden = rb_find_bss(rdev, tmp,
1826 						     BSS_CMP_HIDE_NUL);
1827 			if (hidden) {
1828 				new->pub.hidden_beacon_bss = &hidden->pub;
1829 				list_add(&new->hidden_list,
1830 					 &hidden->hidden_list);
1831 				hidden->refcount++;
1832 
1833 				ies = (void *)rcu_access_pointer(new->pub.beacon_ies);
1834 				rcu_assign_pointer(new->pub.beacon_ies,
1835 						   hidden->pub.beacon_ies);
1836 				if (ies)
1837 					kfree_rcu(ies, rcu_head);
1838 			}
1839 		} else {
1840 			/*
1841 			 * Ok so we found a beacon, and don't have an entry. If
1842 			 * it's a beacon with hidden SSID, we might be in for an
1843 			 * expensive search for any probe responses that should
1844 			 * be grouped with this beacon for updates ...
1845 			 */
1846 			if (!cfg80211_combine_bsses(rdev, new)) {
1847 				bss_ref_put(rdev, new);
1848 				return NULL;
1849 			}
1850 		}
1851 
1852 		if (rdev->bss_entries >= bss_entries_limit &&
1853 		    !cfg80211_bss_expire_oldest(rdev)) {
1854 			bss_ref_put(rdev, new);
1855 			return NULL;
1856 		}
1857 
1858 		/* This must be before the call to bss_ref_get */
1859 		if (tmp->pub.transmitted_bss) {
1860 			new->pub.transmitted_bss = tmp->pub.transmitted_bss;
1861 			bss_ref_get(rdev, bss_from_pub(tmp->pub.transmitted_bss));
1862 		}
1863 
1864 		list_add_tail(&new->list, &rdev->bss_list);
1865 		rdev->bss_entries++;
1866 		rb_insert_bss(rdev, new);
1867 		found = new;
1868 	}
1869 
1870 	rdev->bss_generation++;
1871 	bss_ref_get(rdev, found);
1872 
1873 	return found;
1874 }
1875 
1876 struct cfg80211_internal_bss *
1877 cfg80211_bss_update(struct cfg80211_registered_device *rdev,
1878 		    struct cfg80211_internal_bss *tmp,
1879 		    bool signal_valid, unsigned long ts)
1880 {
1881 	struct cfg80211_internal_bss *res;
1882 
1883 	spin_lock_bh(&rdev->bss_lock);
1884 	res = __cfg80211_bss_update(rdev, tmp, signal_valid, ts);
1885 	spin_unlock_bh(&rdev->bss_lock);
1886 
1887 	return res;
1888 }
1889 
1890 int cfg80211_get_ies_channel_number(const u8 *ie, size_t ielen,
1891 				    enum nl80211_band band)
1892 {
1893 	const struct element *tmp;
1894 
1895 	if (band == NL80211_BAND_6GHZ) {
1896 		struct ieee80211_he_operation *he_oper;
1897 
1898 		tmp = cfg80211_find_ext_elem(WLAN_EID_EXT_HE_OPERATION, ie,
1899 					     ielen);
1900 		if (tmp && tmp->datalen >= sizeof(*he_oper) &&
1901 		    tmp->datalen >= ieee80211_he_oper_size(&tmp->data[1])) {
1902 			const struct ieee80211_he_6ghz_oper *he_6ghz_oper;
1903 
1904 			he_oper = (void *)&tmp->data[1];
1905 
1906 			he_6ghz_oper = ieee80211_he_6ghz_oper(he_oper);
1907 			if (!he_6ghz_oper)
1908 				return -1;
1909 
1910 			return he_6ghz_oper->primary;
1911 		}
1912 	} else if (band == NL80211_BAND_S1GHZ) {
1913 		tmp = cfg80211_find_elem(WLAN_EID_S1G_OPERATION, ie, ielen);
1914 		if (tmp && tmp->datalen >= sizeof(struct ieee80211_s1g_oper_ie)) {
1915 			struct ieee80211_s1g_oper_ie *s1gop = (void *)tmp->data;
1916 
1917 			return s1gop->oper_ch;
1918 		}
1919 	} else {
1920 		tmp = cfg80211_find_elem(WLAN_EID_DS_PARAMS, ie, ielen);
1921 		if (tmp && tmp->datalen == 1)
1922 			return tmp->data[0];
1923 
1924 		tmp = cfg80211_find_elem(WLAN_EID_HT_OPERATION, ie, ielen);
1925 		if (tmp &&
1926 		    tmp->datalen >= sizeof(struct ieee80211_ht_operation)) {
1927 			struct ieee80211_ht_operation *htop = (void *)tmp->data;
1928 
1929 			return htop->primary_chan;
1930 		}
1931 	}
1932 
1933 	return -1;
1934 }
1935 EXPORT_SYMBOL(cfg80211_get_ies_channel_number);
1936 
1937 /*
1938  * Update RX channel information based on the available frame payload
1939  * information. This is mainly for the 2.4 GHz band where frames can be received
1940  * from neighboring channels and the Beacon frames use the DSSS Parameter Set
1941  * element to indicate the current (transmitting) channel, but this might also
1942  * be needed on other bands if RX frequency does not match with the actual
1943  * operating channel of a BSS, or if the AP reports a different primary channel.
1944  */
1945 static struct ieee80211_channel *
1946 cfg80211_get_bss_channel(struct wiphy *wiphy, const u8 *ie, size_t ielen,
1947 			 struct ieee80211_channel *channel,
1948 			 enum nl80211_bss_scan_width scan_width)
1949 {
1950 	u32 freq;
1951 	int channel_number;
1952 	struct ieee80211_channel *alt_channel;
1953 
1954 	channel_number = cfg80211_get_ies_channel_number(ie, ielen,
1955 							 channel->band);
1956 
1957 	if (channel_number < 0) {
1958 		/* No channel information in frame payload */
1959 		return channel;
1960 	}
1961 
1962 	freq = ieee80211_channel_to_freq_khz(channel_number, channel->band);
1963 
1964 	/*
1965 	 * Frame info (beacon/prob res) is the same as received channel,
1966 	 * no need for further processing.
1967 	 */
1968 	if (freq == ieee80211_channel_to_khz(channel))
1969 		return channel;
1970 
1971 	alt_channel = ieee80211_get_channel_khz(wiphy, freq);
1972 	if (!alt_channel) {
1973 		if (channel->band == NL80211_BAND_2GHZ ||
1974 		    channel->band == NL80211_BAND_6GHZ) {
1975 			/*
1976 			 * Better not allow unexpected channels when that could
1977 			 * be going beyond the 1-11 range (e.g., discovering
1978 			 * BSS on channel 12 when radio is configured for
1979 			 * channel 11) or beyond the 6 GHz channel range.
1980 			 */
1981 			return NULL;
1982 		}
1983 
1984 		/* No match for the payload channel number - ignore it */
1985 		return channel;
1986 	}
1987 
1988 	if (scan_width == NL80211_BSS_CHAN_WIDTH_10 ||
1989 	    scan_width == NL80211_BSS_CHAN_WIDTH_5) {
1990 		/*
1991 		 * Ignore channel number in 5 and 10 MHz channels where there
1992 		 * may not be an n:1 or 1:n mapping between frequencies and
1993 		 * channel numbers.
1994 		 */
1995 		return channel;
1996 	}
1997 
1998 	/*
1999 	 * Use the channel determined through the payload channel number
2000 	 * instead of the RX channel reported by the driver.
2001 	 */
2002 	if (alt_channel->flags & IEEE80211_CHAN_DISABLED)
2003 		return NULL;
2004 	return alt_channel;
2005 }
2006 
2007 struct cfg80211_inform_single_bss_data {
2008 	struct cfg80211_inform_bss *drv_data;
2009 	enum cfg80211_bss_frame_type ftype;
2010 	struct ieee80211_channel *channel;
2011 	u8 bssid[ETH_ALEN];
2012 	u64 tsf;
2013 	u16 capability;
2014 	u16 beacon_interval;
2015 	const u8 *ie;
2016 	size_t ielen;
2017 
2018 	enum {
2019 		BSS_SOURCE_DIRECT = 0,
2020 		BSS_SOURCE_MBSSID,
2021 		BSS_SOURCE_STA_PROFILE,
2022 	} bss_source;
2023 	/* Set if reporting bss_source != BSS_SOURCE_DIRECT */
2024 	struct cfg80211_bss *source_bss;
2025 	u8 max_bssid_indicator;
2026 	u8 bssid_index;
2027 };
2028 
2029 /* Returned bss is reference counted and must be cleaned up appropriately. */
2030 static struct cfg80211_bss *
2031 cfg80211_inform_single_bss_data(struct wiphy *wiphy,
2032 				struct cfg80211_inform_single_bss_data *data,
2033 				gfp_t gfp)
2034 {
2035 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
2036 	struct cfg80211_inform_bss *drv_data = data->drv_data;
2037 	struct cfg80211_bss_ies *ies;
2038 	struct ieee80211_channel *channel;
2039 	struct cfg80211_internal_bss tmp = {}, *res;
2040 	int bss_type;
2041 	bool signal_valid;
2042 	unsigned long ts;
2043 
2044 	if (WARN_ON(!wiphy))
2045 		return NULL;
2046 
2047 	if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC &&
2048 		    (drv_data->signal < 0 || drv_data->signal > 100)))
2049 		return NULL;
2050 
2051 	if (WARN_ON(data->bss_source != BSS_SOURCE_DIRECT && !data->source_bss))
2052 		return NULL;
2053 
2054 	channel = data->channel;
2055 	if (!channel)
2056 		channel = cfg80211_get_bss_channel(wiphy, data->ie, data->ielen,
2057 						   drv_data->chan,
2058 						   drv_data->scan_width);
2059 	if (!channel)
2060 		return NULL;
2061 
2062 	memcpy(tmp.pub.bssid, data->bssid, ETH_ALEN);
2063 	tmp.pub.channel = channel;
2064 	tmp.pub.scan_width = drv_data->scan_width;
2065 	if (data->bss_source != BSS_SOURCE_STA_PROFILE)
2066 		tmp.pub.signal = drv_data->signal;
2067 	else
2068 		tmp.pub.signal = 0;
2069 	tmp.pub.beacon_interval = data->beacon_interval;
2070 	tmp.pub.capability = data->capability;
2071 	tmp.ts_boottime = drv_data->boottime_ns;
2072 	tmp.parent_tsf = drv_data->parent_tsf;
2073 	ether_addr_copy(tmp.parent_bssid, drv_data->parent_bssid);
2074 
2075 	if (data->bss_source != BSS_SOURCE_DIRECT) {
2076 		tmp.pub.transmitted_bss = data->source_bss;
2077 		ts = bss_from_pub(data->source_bss)->ts;
2078 		tmp.pub.bssid_index = data->bssid_index;
2079 		tmp.pub.max_bssid_indicator = data->max_bssid_indicator;
2080 	} else {
2081 		ts = jiffies;
2082 
2083 		if (channel->band == NL80211_BAND_60GHZ) {
2084 			bss_type = data->capability &
2085 				   WLAN_CAPABILITY_DMG_TYPE_MASK;
2086 			if (bss_type == WLAN_CAPABILITY_DMG_TYPE_AP ||
2087 			    bss_type == WLAN_CAPABILITY_DMG_TYPE_PBSS)
2088 				regulatory_hint_found_beacon(wiphy, channel,
2089 							     gfp);
2090 		} else {
2091 			if (data->capability & WLAN_CAPABILITY_ESS)
2092 				regulatory_hint_found_beacon(wiphy, channel,
2093 							     gfp);
2094 		}
2095 	}
2096 
2097 	/*
2098 	 * If we do not know here whether the IEs are from a Beacon or Probe
2099 	 * Response frame, we need to pick one of the options and only use it
2100 	 * with the driver that does not provide the full Beacon/Probe Response
2101 	 * frame. Use Beacon frame pointer to avoid indicating that this should
2102 	 * override the IEs pointer should we have received an earlier
2103 	 * indication of Probe Response data.
2104 	 */
2105 	ies = kzalloc(sizeof(*ies) + data->ielen, gfp);
2106 	if (!ies)
2107 		return NULL;
2108 	ies->len = data->ielen;
2109 	ies->tsf = data->tsf;
2110 	ies->from_beacon = false;
2111 	memcpy(ies->data, data->ie, data->ielen);
2112 
2113 	switch (data->ftype) {
2114 	case CFG80211_BSS_FTYPE_BEACON:
2115 		ies->from_beacon = true;
2116 		fallthrough;
2117 	case CFG80211_BSS_FTYPE_UNKNOWN:
2118 		rcu_assign_pointer(tmp.pub.beacon_ies, ies);
2119 		break;
2120 	case CFG80211_BSS_FTYPE_PRESP:
2121 		rcu_assign_pointer(tmp.pub.proberesp_ies, ies);
2122 		break;
2123 	}
2124 	rcu_assign_pointer(tmp.pub.ies, ies);
2125 
2126 	signal_valid = drv_data->chan == channel;
2127 	spin_lock_bh(&rdev->bss_lock);
2128 	res = __cfg80211_bss_update(rdev, &tmp, signal_valid, ts);
2129 	if (!res)
2130 		goto drop;
2131 
2132 	rdev_inform_bss(rdev, &res->pub, ies, drv_data->drv_data);
2133 
2134 	if (data->bss_source == BSS_SOURCE_MBSSID) {
2135 		/* this is a nontransmitting bss, we need to add it to
2136 		 * transmitting bss' list if it is not there
2137 		 */
2138 		if (cfg80211_add_nontrans_list(data->source_bss, &res->pub)) {
2139 			if (__cfg80211_unlink_bss(rdev, res)) {
2140 				rdev->bss_generation++;
2141 				res = NULL;
2142 			}
2143 		}
2144 
2145 		if (!res)
2146 			goto drop;
2147 	}
2148 	spin_unlock_bh(&rdev->bss_lock);
2149 
2150 	trace_cfg80211_return_bss(&res->pub);
2151 	/* __cfg80211_bss_update gives us a referenced result */
2152 	return &res->pub;
2153 
2154 drop:
2155 	spin_unlock_bh(&rdev->bss_lock);
2156 	return NULL;
2157 }
2158 
2159 static const struct element
2160 *cfg80211_get_profile_continuation(const u8 *ie, size_t ielen,
2161 				   const struct element *mbssid_elem,
2162 				   const struct element *sub_elem)
2163 {
2164 	const u8 *mbssid_end = mbssid_elem->data + mbssid_elem->datalen;
2165 	const struct element *next_mbssid;
2166 	const struct element *next_sub;
2167 
2168 	next_mbssid = cfg80211_find_elem(WLAN_EID_MULTIPLE_BSSID,
2169 					 mbssid_end,
2170 					 ielen - (mbssid_end - ie));
2171 
2172 	/*
2173 	 * If it is not the last subelement in current MBSSID IE or there isn't
2174 	 * a next MBSSID IE - profile is complete.
2175 	*/
2176 	if ((sub_elem->data + sub_elem->datalen < mbssid_end - 1) ||
2177 	    !next_mbssid)
2178 		return NULL;
2179 
2180 	/* For any length error, just return NULL */
2181 
2182 	if (next_mbssid->datalen < 4)
2183 		return NULL;
2184 
2185 	next_sub = (void *)&next_mbssid->data[1];
2186 
2187 	if (next_mbssid->data + next_mbssid->datalen <
2188 	    next_sub->data + next_sub->datalen)
2189 		return NULL;
2190 
2191 	if (next_sub->id != 0 || next_sub->datalen < 2)
2192 		return NULL;
2193 
2194 	/*
2195 	 * Check if the first element in the next sub element is a start
2196 	 * of a new profile
2197 	 */
2198 	return next_sub->data[0] == WLAN_EID_NON_TX_BSSID_CAP ?
2199 	       NULL : next_mbssid;
2200 }
2201 
2202 size_t cfg80211_merge_profile(const u8 *ie, size_t ielen,
2203 			      const struct element *mbssid_elem,
2204 			      const struct element *sub_elem,
2205 			      u8 *merged_ie, size_t max_copy_len)
2206 {
2207 	size_t copied_len = sub_elem->datalen;
2208 	const struct element *next_mbssid;
2209 
2210 	if (sub_elem->datalen > max_copy_len)
2211 		return 0;
2212 
2213 	memcpy(merged_ie, sub_elem->data, sub_elem->datalen);
2214 
2215 	while ((next_mbssid = cfg80211_get_profile_continuation(ie, ielen,
2216 								mbssid_elem,
2217 								sub_elem))) {
2218 		const struct element *next_sub = (void *)&next_mbssid->data[1];
2219 
2220 		if (copied_len + next_sub->datalen > max_copy_len)
2221 			break;
2222 		memcpy(merged_ie + copied_len, next_sub->data,
2223 		       next_sub->datalen);
2224 		copied_len += next_sub->datalen;
2225 	}
2226 
2227 	return copied_len;
2228 }
2229 EXPORT_SYMBOL(cfg80211_merge_profile);
2230 
2231 static void
2232 cfg80211_parse_mbssid_data(struct wiphy *wiphy,
2233 			   struct cfg80211_inform_single_bss_data *tx_data,
2234 			   struct cfg80211_bss *source_bss,
2235 			   gfp_t gfp)
2236 {
2237 	struct cfg80211_inform_single_bss_data data = {
2238 		.drv_data = tx_data->drv_data,
2239 		.ftype = tx_data->ftype,
2240 		.tsf = tx_data->tsf,
2241 		.beacon_interval = tx_data->beacon_interval,
2242 		.source_bss = source_bss,
2243 		.bss_source = BSS_SOURCE_MBSSID,
2244 	};
2245 	const u8 *mbssid_index_ie;
2246 	const struct element *elem, *sub;
2247 	u8 *new_ie, *profile;
2248 	u64 seen_indices = 0;
2249 	struct cfg80211_bss *bss;
2250 
2251 	if (!source_bss)
2252 		return;
2253 	if (!cfg80211_find_elem(WLAN_EID_MULTIPLE_BSSID,
2254 				tx_data->ie, tx_data->ielen))
2255 		return;
2256 	if (!wiphy->support_mbssid)
2257 		return;
2258 	if (wiphy->support_only_he_mbssid &&
2259 	    !cfg80211_find_ext_elem(WLAN_EID_EXT_HE_CAPABILITY,
2260 				    tx_data->ie, tx_data->ielen))
2261 		return;
2262 
2263 	new_ie = kmalloc(IEEE80211_MAX_DATA_LEN, gfp);
2264 	if (!new_ie)
2265 		return;
2266 
2267 	profile = kmalloc(tx_data->ielen, gfp);
2268 	if (!profile)
2269 		goto out;
2270 
2271 	for_each_element_id(elem, WLAN_EID_MULTIPLE_BSSID,
2272 			    tx_data->ie, tx_data->ielen) {
2273 		if (elem->datalen < 4)
2274 			continue;
2275 		if (elem->data[0] < 1 || (int)elem->data[0] > 8)
2276 			continue;
2277 		for_each_element(sub, elem->data + 1, elem->datalen - 1) {
2278 			u8 profile_len;
2279 
2280 			if (sub->id != 0 || sub->datalen < 4) {
2281 				/* not a valid BSS profile */
2282 				continue;
2283 			}
2284 
2285 			if (sub->data[0] != WLAN_EID_NON_TX_BSSID_CAP ||
2286 			    sub->data[1] != 2) {
2287 				/* The first element within the Nontransmitted
2288 				 * BSSID Profile is not the Nontransmitted
2289 				 * BSSID Capability element.
2290 				 */
2291 				continue;
2292 			}
2293 
2294 			memset(profile, 0, tx_data->ielen);
2295 			profile_len = cfg80211_merge_profile(tx_data->ie,
2296 							     tx_data->ielen,
2297 							     elem,
2298 							     sub,
2299 							     profile,
2300 							     tx_data->ielen);
2301 
2302 			/* found a Nontransmitted BSSID Profile */
2303 			mbssid_index_ie = cfg80211_find_ie
2304 				(WLAN_EID_MULTI_BSSID_IDX,
2305 				 profile, profile_len);
2306 			if (!mbssid_index_ie || mbssid_index_ie[1] < 1 ||
2307 			    mbssid_index_ie[2] == 0 ||
2308 			    mbssid_index_ie[2] > 46) {
2309 				/* No valid Multiple BSSID-Index element */
2310 				continue;
2311 			}
2312 
2313 			if (seen_indices & BIT_ULL(mbssid_index_ie[2]))
2314 				/* We don't support legacy split of a profile */
2315 				net_dbg_ratelimited("Partial info for BSSID index %d\n",
2316 						    mbssid_index_ie[2]);
2317 
2318 			seen_indices |= BIT_ULL(mbssid_index_ie[2]);
2319 
2320 			data.bssid_index = mbssid_index_ie[2];
2321 			data.max_bssid_indicator = elem->data[0];
2322 
2323 			cfg80211_gen_new_bssid(tx_data->bssid,
2324 					       data.max_bssid_indicator,
2325 					       data.bssid_index,
2326 					       data.bssid);
2327 
2328 			memset(new_ie, 0, IEEE80211_MAX_DATA_LEN);
2329 			data.ie = new_ie;
2330 			data.ielen = cfg80211_gen_new_ie(tx_data->ie,
2331 							 tx_data->ielen,
2332 							 profile,
2333 							 profile_len,
2334 							 new_ie,
2335 							 IEEE80211_MAX_DATA_LEN);
2336 			if (!data.ielen)
2337 				continue;
2338 
2339 			data.capability = get_unaligned_le16(profile + 2);
2340 			bss = cfg80211_inform_single_bss_data(wiphy, &data, gfp);
2341 			if (!bss)
2342 				break;
2343 			cfg80211_put_bss(wiphy, bss);
2344 		}
2345 	}
2346 
2347 out:
2348 	kfree(new_ie);
2349 	kfree(profile);
2350 }
2351 
2352 ssize_t cfg80211_defragment_element(const struct element *elem, const u8 *ies,
2353 				    size_t ieslen, u8 *data, size_t data_len,
2354 				    u8 frag_id)
2355 {
2356 	const struct element *next;
2357 	ssize_t copied;
2358 	u8 elem_datalen;
2359 
2360 	if (!elem)
2361 		return -EINVAL;
2362 
2363 	/* elem might be invalid after the memmove */
2364 	next = (void *)(elem->data + elem->datalen);
2365 	elem_datalen = elem->datalen;
2366 
2367 	if (elem->id == WLAN_EID_EXTENSION) {
2368 		copied = elem->datalen - 1;
2369 		if (copied > data_len)
2370 			return -ENOSPC;
2371 
2372 		memmove(data, elem->data + 1, copied);
2373 	} else {
2374 		copied = elem->datalen;
2375 		if (copied > data_len)
2376 			return -ENOSPC;
2377 
2378 		memmove(data, elem->data, copied);
2379 	}
2380 
2381 	/* Fragmented elements must have 255 bytes */
2382 	if (elem_datalen < 255)
2383 		return copied;
2384 
2385 	for (elem = next;
2386 	     elem->data < ies + ieslen &&
2387 		elem->data + elem->datalen <= ies + ieslen;
2388 	     elem = next) {
2389 		/* elem might be invalid after the memmove */
2390 		next = (void *)(elem->data + elem->datalen);
2391 
2392 		if (elem->id != frag_id)
2393 			break;
2394 
2395 		elem_datalen = elem->datalen;
2396 
2397 		if (copied + elem_datalen > data_len)
2398 			return -ENOSPC;
2399 
2400 		memmove(data + copied, elem->data, elem_datalen);
2401 		copied += elem_datalen;
2402 
2403 		/* Only the last fragment may be short */
2404 		if (elem_datalen != 255)
2405 			break;
2406 	}
2407 
2408 	return copied;
2409 }
2410 EXPORT_SYMBOL(cfg80211_defragment_element);
2411 
2412 struct cfg80211_mle {
2413 	struct ieee80211_multi_link_elem *mle;
2414 	struct ieee80211_mle_per_sta_profile
2415 		*sta_prof[IEEE80211_MLD_MAX_NUM_LINKS];
2416 	ssize_t sta_prof_len[IEEE80211_MLD_MAX_NUM_LINKS];
2417 
2418 	u8 data[];
2419 };
2420 
2421 static struct cfg80211_mle *
2422 cfg80211_defrag_mle(const struct element *mle, const u8 *ie, size_t ielen,
2423 		    gfp_t gfp)
2424 {
2425 	const struct element *elem;
2426 	struct cfg80211_mle *res;
2427 	size_t buf_len;
2428 	ssize_t mle_len;
2429 	u8 common_size, idx;
2430 
2431 	if (!mle || !ieee80211_mle_size_ok(mle->data + 1, mle->datalen - 1))
2432 		return NULL;
2433 
2434 	/* Required length for first defragmentation */
2435 	buf_len = mle->datalen - 1;
2436 	for_each_element(elem, mle->data + mle->datalen,
2437 			 ielen - sizeof(*mle) + mle->datalen) {
2438 		if (elem->id != WLAN_EID_FRAGMENT)
2439 			break;
2440 
2441 		buf_len += elem->datalen;
2442 	}
2443 
2444 	res = kzalloc(struct_size(res, data, buf_len), gfp);
2445 	if (!res)
2446 		return NULL;
2447 
2448 	mle_len = cfg80211_defragment_element(mle, ie, ielen,
2449 					      res->data, buf_len,
2450 					      WLAN_EID_FRAGMENT);
2451 	if (mle_len < 0)
2452 		goto error;
2453 
2454 	res->mle = (void *)res->data;
2455 
2456 	/* Find the sub-element area in the buffer */
2457 	common_size = ieee80211_mle_common_size((u8 *)res->mle);
2458 	ie = res->data + common_size;
2459 	ielen = mle_len - common_size;
2460 
2461 	idx = 0;
2462 	for_each_element_id(elem, IEEE80211_MLE_SUBELEM_PER_STA_PROFILE,
2463 			    ie, ielen) {
2464 		res->sta_prof[idx] = (void *)elem->data;
2465 		res->sta_prof_len[idx] = elem->datalen;
2466 
2467 		idx++;
2468 		if (idx >= IEEE80211_MLD_MAX_NUM_LINKS)
2469 			break;
2470 	}
2471 	if (!for_each_element_completed(elem, ie, ielen))
2472 		goto error;
2473 
2474 	/* Defragment sta_info in-place */
2475 	for (idx = 0; idx < IEEE80211_MLD_MAX_NUM_LINKS && res->sta_prof[idx];
2476 	     idx++) {
2477 		if (res->sta_prof_len[idx] < 255)
2478 			continue;
2479 
2480 		elem = (void *)res->sta_prof[idx] - 2;
2481 
2482 		if (idx + 1 < ARRAY_SIZE(res->sta_prof) &&
2483 		    res->sta_prof[idx + 1])
2484 			buf_len = (u8 *)res->sta_prof[idx + 1] -
2485 				  (u8 *)res->sta_prof[idx];
2486 		else
2487 			buf_len = ielen + ie - (u8 *)elem;
2488 
2489 		res->sta_prof_len[idx] =
2490 			cfg80211_defragment_element(elem,
2491 						    (u8 *)elem, buf_len,
2492 						    (u8 *)res->sta_prof[idx],
2493 						    buf_len,
2494 						    IEEE80211_MLE_SUBELEM_FRAGMENT);
2495 		if (res->sta_prof_len[idx] < 0)
2496 			goto error;
2497 	}
2498 
2499 	return res;
2500 
2501 error:
2502 	kfree(res);
2503 	return NULL;
2504 }
2505 
2506 static bool
2507 cfg80211_tbtt_info_for_mld_ap(const u8 *ie, size_t ielen, u8 mld_id, u8 link_id,
2508 			      const struct ieee80211_neighbor_ap_info **ap_info,
2509 			      const u8 **tbtt_info)
2510 {
2511 	const struct ieee80211_neighbor_ap_info *info;
2512 	const struct element *rnr;
2513 	const u8 *pos, *end;
2514 
2515 	for_each_element_id(rnr, WLAN_EID_REDUCED_NEIGHBOR_REPORT, ie, ielen) {
2516 		pos = rnr->data;
2517 		end = rnr->data + rnr->datalen;
2518 
2519 		/* RNR IE may contain more than one NEIGHBOR_AP_INFO */
2520 		while (sizeof(*info) <= end - pos) {
2521 			const struct ieee80211_rnr_mld_params *mld_params;
2522 			u16 params;
2523 			u8 length, i, count, mld_params_offset;
2524 			u8 type, lid;
2525 
2526 			info = (void *)pos;
2527 			count = u8_get_bits(info->tbtt_info_hdr,
2528 					    IEEE80211_AP_INFO_TBTT_HDR_COUNT) + 1;
2529 			length = info->tbtt_info_len;
2530 
2531 			pos += sizeof(*info);
2532 
2533 			if (count * length > end - pos)
2534 				return false;
2535 
2536 			type = u8_get_bits(info->tbtt_info_hdr,
2537 					   IEEE80211_AP_INFO_TBTT_HDR_TYPE);
2538 
2539 			/* Only accept full TBTT information. NSTR mobile APs
2540 			 * use the shortened version, but we ignore them here.
2541 			 */
2542 			if (type == IEEE80211_TBTT_INFO_TYPE_TBTT &&
2543 			    length >=
2544 			    offsetofend(struct ieee80211_tbtt_info_ge_11,
2545 					mld_params)) {
2546 				mld_params_offset =
2547 					offsetof(struct ieee80211_tbtt_info_ge_11, mld_params);
2548 			} else {
2549 				pos += count * length;
2550 				continue;
2551 			}
2552 
2553 			for (i = 0; i < count; i++) {
2554 				mld_params = (void *)pos + mld_params_offset;
2555 				params = le16_to_cpu(mld_params->params);
2556 
2557 				lid = u16_get_bits(params,
2558 						   IEEE80211_RNR_MLD_PARAMS_LINK_ID);
2559 
2560 				if (mld_id == mld_params->mld_id &&
2561 				    link_id == lid) {
2562 					*ap_info = info;
2563 					*tbtt_info = pos;
2564 
2565 					return true;
2566 				}
2567 
2568 				pos += length;
2569 			}
2570 		}
2571 	}
2572 
2573 	return false;
2574 }
2575 
2576 static void
2577 cfg80211_parse_ml_elem_sta_data(struct wiphy *wiphy,
2578 				struct cfg80211_inform_single_bss_data *tx_data,
2579 				struct cfg80211_bss *source_bss,
2580 				const struct element *elem,
2581 				gfp_t gfp)
2582 {
2583 	struct cfg80211_inform_single_bss_data data = {
2584 		.drv_data = tx_data->drv_data,
2585 		.ftype = tx_data->ftype,
2586 		.source_bss = source_bss,
2587 		.bss_source = BSS_SOURCE_STA_PROFILE,
2588 	};
2589 	struct ieee80211_multi_link_elem *ml_elem;
2590 	struct cfg80211_mle *mle;
2591 	u16 control;
2592 	u8 *new_ie;
2593 	struct cfg80211_bss *bss;
2594 	int mld_id;
2595 	u16 seen_links = 0;
2596 	const u8 *pos;
2597 	u8 i;
2598 
2599 	if (!ieee80211_mle_size_ok(elem->data + 1, elem->datalen - 1))
2600 		return;
2601 
2602 	ml_elem = (void *)elem->data + 1;
2603 	control = le16_to_cpu(ml_elem->control);
2604 	if (u16_get_bits(control, IEEE80211_ML_CONTROL_TYPE) !=
2605 	    IEEE80211_ML_CONTROL_TYPE_BASIC)
2606 		return;
2607 
2608 	/* Must be present when transmitted by an AP (in a probe response) */
2609 	if (!(control & IEEE80211_MLC_BASIC_PRES_BSS_PARAM_CH_CNT) ||
2610 	    !(control & IEEE80211_MLC_BASIC_PRES_LINK_ID) ||
2611 	    !(control & IEEE80211_MLC_BASIC_PRES_MLD_CAPA_OP))
2612 		return;
2613 
2614 	/* length + MLD MAC address + link ID info + BSS Params Change Count */
2615 	pos = ml_elem->variable + 1 + 6 + 1 + 1;
2616 
2617 	if (u16_get_bits(control, IEEE80211_MLC_BASIC_PRES_MED_SYNC_DELAY))
2618 		pos += 2;
2619 	if (u16_get_bits(control, IEEE80211_MLC_BASIC_PRES_EML_CAPA))
2620 		pos += 2;
2621 
2622 	/* MLD capabilities and operations */
2623 	pos += 2;
2624 
2625 	/*
2626 	 * The MLD ID of the reporting AP is always zero. It is set if the AP
2627 	 * is part of an MBSSID set and will be non-zero for ML Elements
2628 	 * relating to a nontransmitted BSS (matching the Multi-BSSID Index,
2629 	 * Draft P802.11be_D3.2, 35.3.4.2)
2630 	 */
2631 	if (u16_get_bits(control, IEEE80211_MLC_BASIC_PRES_MLD_ID)) {
2632 		mld_id = *pos;
2633 		pos += 1;
2634 	} else {
2635 		mld_id = 0;
2636 	}
2637 
2638 	/* Extended MLD capabilities and operations */
2639 	pos += 2;
2640 
2641 	/* Fully defrag the ML element for sta information/profile iteration */
2642 	mle = cfg80211_defrag_mle(elem, tx_data->ie, tx_data->ielen, gfp);
2643 	if (!mle)
2644 		return;
2645 
2646 	new_ie = kmalloc(IEEE80211_MAX_DATA_LEN, gfp);
2647 	if (!new_ie)
2648 		goto out;
2649 
2650 	for (i = 0; i < ARRAY_SIZE(mle->sta_prof) && mle->sta_prof[i]; i++) {
2651 		const struct ieee80211_neighbor_ap_info *ap_info;
2652 		enum nl80211_band band;
2653 		u32 freq;
2654 		const u8 *profile;
2655 		const u8 *tbtt_info;
2656 		ssize_t profile_len;
2657 		u8 link_id;
2658 
2659 		if (!ieee80211_mle_basic_sta_prof_size_ok((u8 *)mle->sta_prof[i],
2660 							  mle->sta_prof_len[i]))
2661 			continue;
2662 
2663 		control = le16_to_cpu(mle->sta_prof[i]->control);
2664 
2665 		if (!(control & IEEE80211_MLE_STA_CONTROL_COMPLETE_PROFILE))
2666 			continue;
2667 
2668 		link_id = u16_get_bits(control,
2669 				       IEEE80211_MLE_STA_CONTROL_LINK_ID);
2670 		if (seen_links & BIT(link_id))
2671 			break;
2672 		seen_links |= BIT(link_id);
2673 
2674 		if (!(control & IEEE80211_MLE_STA_CONTROL_BEACON_INT_PRESENT) ||
2675 		    !(control & IEEE80211_MLE_STA_CONTROL_TSF_OFFS_PRESENT) ||
2676 		    !(control & IEEE80211_MLE_STA_CONTROL_STA_MAC_ADDR_PRESENT))
2677 			continue;
2678 
2679 		memcpy(data.bssid, mle->sta_prof[i]->variable, ETH_ALEN);
2680 		data.beacon_interval =
2681 			get_unaligned_le16(mle->sta_prof[i]->variable + 6);
2682 		data.tsf = tx_data->tsf +
2683 			   get_unaligned_le64(mle->sta_prof[i]->variable + 8);
2684 
2685 		/* sta_info_len counts itself */
2686 		profile = mle->sta_prof[i]->variable +
2687 			  mle->sta_prof[i]->sta_info_len - 1;
2688 		profile_len = (u8 *)mle->sta_prof[i] + mle->sta_prof_len[i] -
2689 			      profile;
2690 
2691 		if (profile_len < 2)
2692 			continue;
2693 
2694 		data.capability = get_unaligned_le16(profile);
2695 		profile += 2;
2696 		profile_len -= 2;
2697 
2698 		/* Find in RNR to look up channel information */
2699 		if (!cfg80211_tbtt_info_for_mld_ap(tx_data->ie, tx_data->ielen,
2700 						   mld_id, link_id,
2701 						   &ap_info, &tbtt_info))
2702 			continue;
2703 
2704 		/* We could sanity check the BSSID is included */
2705 
2706 		if (!ieee80211_operating_class_to_band(ap_info->op_class,
2707 						       &band))
2708 			continue;
2709 
2710 		freq = ieee80211_channel_to_freq_khz(ap_info->channel, band);
2711 		data.channel = ieee80211_get_channel_khz(wiphy, freq);
2712 
2713 		/* Generate new elements */
2714 		memset(new_ie, 0, IEEE80211_MAX_DATA_LEN);
2715 		data.ie = new_ie;
2716 		data.ielen = cfg80211_gen_new_ie(tx_data->ie, tx_data->ielen,
2717 						 profile, profile_len,
2718 						 new_ie,
2719 						 IEEE80211_MAX_DATA_LEN);
2720 		if (!data.ielen)
2721 			continue;
2722 
2723 		bss = cfg80211_inform_single_bss_data(wiphy, &data, gfp);
2724 		if (!bss)
2725 			break;
2726 		cfg80211_put_bss(wiphy, bss);
2727 	}
2728 
2729 out:
2730 	kfree(new_ie);
2731 	kfree(mle);
2732 }
2733 
2734 static void cfg80211_parse_ml_sta_data(struct wiphy *wiphy,
2735 				       struct cfg80211_inform_single_bss_data *tx_data,
2736 				       struct cfg80211_bss *source_bss,
2737 				       gfp_t gfp)
2738 {
2739 	const struct element *elem;
2740 
2741 	if (!source_bss)
2742 		return;
2743 
2744 	if (tx_data->ftype != CFG80211_BSS_FTYPE_PRESP)
2745 		return;
2746 
2747 	for_each_element_extid(elem, WLAN_EID_EXT_EHT_MULTI_LINK,
2748 			       tx_data->ie, tx_data->ielen)
2749 		cfg80211_parse_ml_elem_sta_data(wiphy, tx_data, source_bss,
2750 						elem, gfp);
2751 }
2752 
2753 struct cfg80211_bss *
2754 cfg80211_inform_bss_data(struct wiphy *wiphy,
2755 			 struct cfg80211_inform_bss *data,
2756 			 enum cfg80211_bss_frame_type ftype,
2757 			 const u8 *bssid, u64 tsf, u16 capability,
2758 			 u16 beacon_interval, const u8 *ie, size_t ielen,
2759 			 gfp_t gfp)
2760 {
2761 	struct cfg80211_inform_single_bss_data inform_data = {
2762 		.drv_data = data,
2763 		.ftype = ftype,
2764 		.tsf = tsf,
2765 		.capability = capability,
2766 		.beacon_interval = beacon_interval,
2767 		.ie = ie,
2768 		.ielen = ielen,
2769 	};
2770 	struct cfg80211_bss *res;
2771 
2772 	memcpy(inform_data.bssid, bssid, ETH_ALEN);
2773 
2774 	res = cfg80211_inform_single_bss_data(wiphy, &inform_data, gfp);
2775 	if (!res)
2776 		return NULL;
2777 
2778 	cfg80211_parse_mbssid_data(wiphy, &inform_data, res, gfp);
2779 
2780 	cfg80211_parse_ml_sta_data(wiphy, &inform_data, res, gfp);
2781 
2782 	return res;
2783 }
2784 EXPORT_SYMBOL(cfg80211_inform_bss_data);
2785 
2786 /* cfg80211_inform_bss_width_frame helper */
2787 static struct cfg80211_bss *
2788 cfg80211_inform_single_bss_frame_data(struct wiphy *wiphy,
2789 				      struct cfg80211_inform_bss *data,
2790 				      struct ieee80211_mgmt *mgmt, size_t len,
2791 				      gfp_t gfp)
2792 {
2793 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
2794 	struct cfg80211_internal_bss tmp = {}, *res;
2795 	struct cfg80211_bss_ies *ies;
2796 	struct ieee80211_channel *channel;
2797 	bool signal_valid;
2798 	struct ieee80211_ext *ext = NULL;
2799 	u8 *bssid, *variable;
2800 	u16 capability, beacon_int;
2801 	size_t ielen, min_hdr_len = offsetof(struct ieee80211_mgmt,
2802 					     u.probe_resp.variable);
2803 	int bss_type;
2804 
2805 	BUILD_BUG_ON(offsetof(struct ieee80211_mgmt, u.probe_resp.variable) !=
2806 			offsetof(struct ieee80211_mgmt, u.beacon.variable));
2807 
2808 	trace_cfg80211_inform_bss_frame(wiphy, data, mgmt, len);
2809 
2810 	if (WARN_ON(!mgmt))
2811 		return NULL;
2812 
2813 	if (WARN_ON(!wiphy))
2814 		return NULL;
2815 
2816 	if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC &&
2817 		    (data->signal < 0 || data->signal > 100)))
2818 		return NULL;
2819 
2820 	if (ieee80211_is_s1g_beacon(mgmt->frame_control)) {
2821 		ext = (void *) mgmt;
2822 		min_hdr_len = offsetof(struct ieee80211_ext, u.s1g_beacon);
2823 		if (ieee80211_is_s1g_short_beacon(mgmt->frame_control))
2824 			min_hdr_len = offsetof(struct ieee80211_ext,
2825 					       u.s1g_short_beacon.variable);
2826 	}
2827 
2828 	if (WARN_ON(len < min_hdr_len))
2829 		return NULL;
2830 
2831 	ielen = len - min_hdr_len;
2832 	variable = mgmt->u.probe_resp.variable;
2833 	if (ext) {
2834 		if (ieee80211_is_s1g_short_beacon(mgmt->frame_control))
2835 			variable = ext->u.s1g_short_beacon.variable;
2836 		else
2837 			variable = ext->u.s1g_beacon.variable;
2838 	}
2839 
2840 	channel = cfg80211_get_bss_channel(wiphy, variable,
2841 					   ielen, data->chan, data->scan_width);
2842 	if (!channel)
2843 		return NULL;
2844 
2845 	if (ext) {
2846 		const struct ieee80211_s1g_bcn_compat_ie *compat;
2847 		const struct element *elem;
2848 
2849 		elem = cfg80211_find_elem(WLAN_EID_S1G_BCN_COMPAT,
2850 					  variable, ielen);
2851 		if (!elem)
2852 			return NULL;
2853 		if (elem->datalen < sizeof(*compat))
2854 			return NULL;
2855 		compat = (void *)elem->data;
2856 		bssid = ext->u.s1g_beacon.sa;
2857 		capability = le16_to_cpu(compat->compat_info);
2858 		beacon_int = le16_to_cpu(compat->beacon_int);
2859 	} else {
2860 		bssid = mgmt->bssid;
2861 		beacon_int = le16_to_cpu(mgmt->u.probe_resp.beacon_int);
2862 		capability = le16_to_cpu(mgmt->u.probe_resp.capab_info);
2863 	}
2864 
2865 	if (channel->band == NL80211_BAND_60GHZ) {
2866 		bss_type = capability & WLAN_CAPABILITY_DMG_TYPE_MASK;
2867 		if (bss_type == WLAN_CAPABILITY_DMG_TYPE_AP ||
2868 		    bss_type == WLAN_CAPABILITY_DMG_TYPE_PBSS)
2869 			regulatory_hint_found_beacon(wiphy, channel, gfp);
2870 	} else {
2871 		if (capability & WLAN_CAPABILITY_ESS)
2872 			regulatory_hint_found_beacon(wiphy, channel, gfp);
2873 	}
2874 
2875 	ies = kzalloc(sizeof(*ies) + ielen, gfp);
2876 	if (!ies)
2877 		return NULL;
2878 	ies->len = ielen;
2879 	ies->tsf = le64_to_cpu(mgmt->u.probe_resp.timestamp);
2880 	ies->from_beacon = ieee80211_is_beacon(mgmt->frame_control) ||
2881 			   ieee80211_is_s1g_beacon(mgmt->frame_control);
2882 	memcpy(ies->data, variable, ielen);
2883 
2884 	if (ieee80211_is_probe_resp(mgmt->frame_control))
2885 		rcu_assign_pointer(tmp.pub.proberesp_ies, ies);
2886 	else
2887 		rcu_assign_pointer(tmp.pub.beacon_ies, ies);
2888 	rcu_assign_pointer(tmp.pub.ies, ies);
2889 
2890 	memcpy(tmp.pub.bssid, bssid, ETH_ALEN);
2891 	tmp.pub.beacon_interval = beacon_int;
2892 	tmp.pub.capability = capability;
2893 	tmp.pub.channel = channel;
2894 	tmp.pub.scan_width = data->scan_width;
2895 	tmp.pub.signal = data->signal;
2896 	tmp.ts_boottime = data->boottime_ns;
2897 	tmp.parent_tsf = data->parent_tsf;
2898 	tmp.pub.chains = data->chains;
2899 	memcpy(tmp.pub.chain_signal, data->chain_signal, IEEE80211_MAX_CHAINS);
2900 	ether_addr_copy(tmp.parent_bssid, data->parent_bssid);
2901 
2902 	signal_valid = data->chan == channel;
2903 	spin_lock_bh(&rdev->bss_lock);
2904 	res = __cfg80211_bss_update(rdev, &tmp, signal_valid, jiffies);
2905 	if (!res)
2906 		goto drop;
2907 
2908 	rdev_inform_bss(rdev, &res->pub, ies, data->drv_data);
2909 
2910 	spin_unlock_bh(&rdev->bss_lock);
2911 
2912 	trace_cfg80211_return_bss(&res->pub);
2913 	/* __cfg80211_bss_update gives us a referenced result */
2914 	return &res->pub;
2915 
2916 drop:
2917 	spin_unlock_bh(&rdev->bss_lock);
2918 	return NULL;
2919 }
2920 
2921 struct cfg80211_bss *
2922 cfg80211_inform_bss_frame_data(struct wiphy *wiphy,
2923 			       struct cfg80211_inform_bss *data,
2924 			       struct ieee80211_mgmt *mgmt, size_t len,
2925 			       gfp_t gfp)
2926 {
2927 	struct cfg80211_inform_single_bss_data inform_data = {
2928 		.drv_data = data,
2929 		.ie = mgmt->u.probe_resp.variable,
2930 		.ielen = len - offsetof(struct ieee80211_mgmt,
2931 					u.probe_resp.variable),
2932 	};
2933 	struct cfg80211_bss *res;
2934 
2935 	res = cfg80211_inform_single_bss_frame_data(wiphy, data, mgmt,
2936 						    len, gfp);
2937 	if (!res)
2938 		return NULL;
2939 
2940 	/* don't do any further MBSSID/ML handling for S1G */
2941 	if (ieee80211_is_s1g_beacon(mgmt->frame_control))
2942 		return res;
2943 
2944 	inform_data.ftype = ieee80211_is_beacon(mgmt->frame_control) ?
2945 		CFG80211_BSS_FTYPE_BEACON : CFG80211_BSS_FTYPE_PRESP;
2946 	memcpy(inform_data.bssid, mgmt->bssid, ETH_ALEN);
2947 	inform_data.tsf = le64_to_cpu(mgmt->u.probe_resp.timestamp);
2948 	inform_data.beacon_interval =
2949 		le16_to_cpu(mgmt->u.probe_resp.beacon_int);
2950 
2951 	/* process each non-transmitting bss */
2952 	cfg80211_parse_mbssid_data(wiphy, &inform_data, res, gfp);
2953 
2954 	cfg80211_parse_ml_sta_data(wiphy, &inform_data, res, gfp);
2955 
2956 	return res;
2957 }
2958 EXPORT_SYMBOL(cfg80211_inform_bss_frame_data);
2959 
2960 void cfg80211_ref_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
2961 {
2962 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
2963 
2964 	if (!pub)
2965 		return;
2966 
2967 	spin_lock_bh(&rdev->bss_lock);
2968 	bss_ref_get(rdev, bss_from_pub(pub));
2969 	spin_unlock_bh(&rdev->bss_lock);
2970 }
2971 EXPORT_SYMBOL(cfg80211_ref_bss);
2972 
2973 void cfg80211_put_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
2974 {
2975 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
2976 
2977 	if (!pub)
2978 		return;
2979 
2980 	spin_lock_bh(&rdev->bss_lock);
2981 	bss_ref_put(rdev, bss_from_pub(pub));
2982 	spin_unlock_bh(&rdev->bss_lock);
2983 }
2984 EXPORT_SYMBOL(cfg80211_put_bss);
2985 
2986 void cfg80211_unlink_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
2987 {
2988 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
2989 	struct cfg80211_internal_bss *bss, *tmp1;
2990 	struct cfg80211_bss *nontrans_bss, *tmp;
2991 
2992 	if (WARN_ON(!pub))
2993 		return;
2994 
2995 	bss = bss_from_pub(pub);
2996 
2997 	spin_lock_bh(&rdev->bss_lock);
2998 	if (list_empty(&bss->list))
2999 		goto out;
3000 
3001 	list_for_each_entry_safe(nontrans_bss, tmp,
3002 				 &pub->nontrans_list,
3003 				 nontrans_list) {
3004 		tmp1 = bss_from_pub(nontrans_bss);
3005 		if (__cfg80211_unlink_bss(rdev, tmp1))
3006 			rdev->bss_generation++;
3007 	}
3008 
3009 	if (__cfg80211_unlink_bss(rdev, bss))
3010 		rdev->bss_generation++;
3011 out:
3012 	spin_unlock_bh(&rdev->bss_lock);
3013 }
3014 EXPORT_SYMBOL(cfg80211_unlink_bss);
3015 
3016 void cfg80211_bss_iter(struct wiphy *wiphy,
3017 		       struct cfg80211_chan_def *chandef,
3018 		       void (*iter)(struct wiphy *wiphy,
3019 				    struct cfg80211_bss *bss,
3020 				    void *data),
3021 		       void *iter_data)
3022 {
3023 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
3024 	struct cfg80211_internal_bss *bss;
3025 
3026 	spin_lock_bh(&rdev->bss_lock);
3027 
3028 	list_for_each_entry(bss, &rdev->bss_list, list) {
3029 		if (!chandef || cfg80211_is_sub_chan(chandef, bss->pub.channel,
3030 						     false))
3031 			iter(wiphy, &bss->pub, iter_data);
3032 	}
3033 
3034 	spin_unlock_bh(&rdev->bss_lock);
3035 }
3036 EXPORT_SYMBOL(cfg80211_bss_iter);
3037 
3038 void cfg80211_update_assoc_bss_entry(struct wireless_dev *wdev,
3039 				     unsigned int link_id,
3040 				     struct ieee80211_channel *chan)
3041 {
3042 	struct wiphy *wiphy = wdev->wiphy;
3043 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
3044 	struct cfg80211_internal_bss *cbss = wdev->links[link_id].client.current_bss;
3045 	struct cfg80211_internal_bss *new = NULL;
3046 	struct cfg80211_internal_bss *bss;
3047 	struct cfg80211_bss *nontrans_bss;
3048 	struct cfg80211_bss *tmp;
3049 
3050 	spin_lock_bh(&rdev->bss_lock);
3051 
3052 	/*
3053 	 * Some APs use CSA also for bandwidth changes, i.e., without actually
3054 	 * changing the control channel, so no need to update in such a case.
3055 	 */
3056 	if (cbss->pub.channel == chan)
3057 		goto done;
3058 
3059 	/* use transmitting bss */
3060 	if (cbss->pub.transmitted_bss)
3061 		cbss = bss_from_pub(cbss->pub.transmitted_bss);
3062 
3063 	cbss->pub.channel = chan;
3064 
3065 	list_for_each_entry(bss, &rdev->bss_list, list) {
3066 		if (!cfg80211_bss_type_match(bss->pub.capability,
3067 					     bss->pub.channel->band,
3068 					     wdev->conn_bss_type))
3069 			continue;
3070 
3071 		if (bss == cbss)
3072 			continue;
3073 
3074 		if (!cmp_bss(&bss->pub, &cbss->pub, BSS_CMP_REGULAR)) {
3075 			new = bss;
3076 			break;
3077 		}
3078 	}
3079 
3080 	if (new) {
3081 		/* to save time, update IEs for transmitting bss only */
3082 		if (cfg80211_update_known_bss(rdev, cbss, new, false)) {
3083 			new->pub.proberesp_ies = NULL;
3084 			new->pub.beacon_ies = NULL;
3085 		}
3086 
3087 		list_for_each_entry_safe(nontrans_bss, tmp,
3088 					 &new->pub.nontrans_list,
3089 					 nontrans_list) {
3090 			bss = bss_from_pub(nontrans_bss);
3091 			if (__cfg80211_unlink_bss(rdev, bss))
3092 				rdev->bss_generation++;
3093 		}
3094 
3095 		WARN_ON(atomic_read(&new->hold));
3096 		if (!WARN_ON(!__cfg80211_unlink_bss(rdev, new)))
3097 			rdev->bss_generation++;
3098 	}
3099 
3100 	rb_erase(&cbss->rbn, &rdev->bss_tree);
3101 	rb_insert_bss(rdev, cbss);
3102 	rdev->bss_generation++;
3103 
3104 	list_for_each_entry_safe(nontrans_bss, tmp,
3105 				 &cbss->pub.nontrans_list,
3106 				 nontrans_list) {
3107 		bss = bss_from_pub(nontrans_bss);
3108 		bss->pub.channel = chan;
3109 		rb_erase(&bss->rbn, &rdev->bss_tree);
3110 		rb_insert_bss(rdev, bss);
3111 		rdev->bss_generation++;
3112 	}
3113 
3114 done:
3115 	spin_unlock_bh(&rdev->bss_lock);
3116 }
3117 
3118 #ifdef CONFIG_CFG80211_WEXT
3119 static struct cfg80211_registered_device *
3120 cfg80211_get_dev_from_ifindex(struct net *net, int ifindex)
3121 {
3122 	struct cfg80211_registered_device *rdev;
3123 	struct net_device *dev;
3124 
3125 	ASSERT_RTNL();
3126 
3127 	dev = dev_get_by_index(net, ifindex);
3128 	if (!dev)
3129 		return ERR_PTR(-ENODEV);
3130 	if (dev->ieee80211_ptr)
3131 		rdev = wiphy_to_rdev(dev->ieee80211_ptr->wiphy);
3132 	else
3133 		rdev = ERR_PTR(-ENODEV);
3134 	dev_put(dev);
3135 	return rdev;
3136 }
3137 
3138 int cfg80211_wext_siwscan(struct net_device *dev,
3139 			  struct iw_request_info *info,
3140 			  union iwreq_data *wrqu, char *extra)
3141 {
3142 	struct cfg80211_registered_device *rdev;
3143 	struct wiphy *wiphy;
3144 	struct iw_scan_req *wreq = NULL;
3145 	struct cfg80211_scan_request *creq;
3146 	int i, err, n_channels = 0;
3147 	enum nl80211_band band;
3148 
3149 	if (!netif_running(dev))
3150 		return -ENETDOWN;
3151 
3152 	if (wrqu->data.length == sizeof(struct iw_scan_req))
3153 		wreq = (struct iw_scan_req *)extra;
3154 
3155 	rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
3156 
3157 	if (IS_ERR(rdev))
3158 		return PTR_ERR(rdev);
3159 
3160 	if (rdev->scan_req || rdev->scan_msg)
3161 		return -EBUSY;
3162 
3163 	wiphy = &rdev->wiphy;
3164 
3165 	/* Determine number of channels, needed to allocate creq */
3166 	if (wreq && wreq->num_channels)
3167 		n_channels = wreq->num_channels;
3168 	else
3169 		n_channels = ieee80211_get_num_supported_channels(wiphy);
3170 
3171 	creq = kzalloc(sizeof(*creq) + sizeof(struct cfg80211_ssid) +
3172 		       n_channels * sizeof(void *),
3173 		       GFP_ATOMIC);
3174 	if (!creq)
3175 		return -ENOMEM;
3176 
3177 	creq->wiphy = wiphy;
3178 	creq->wdev = dev->ieee80211_ptr;
3179 	/* SSIDs come after channels */
3180 	creq->ssids = (void *)&creq->channels[n_channels];
3181 	creq->n_channels = n_channels;
3182 	creq->n_ssids = 1;
3183 	creq->scan_start = jiffies;
3184 
3185 	/* translate "Scan on frequencies" request */
3186 	i = 0;
3187 	for (band = 0; band < NUM_NL80211_BANDS; band++) {
3188 		int j;
3189 
3190 		if (!wiphy->bands[band])
3191 			continue;
3192 
3193 		for (j = 0; j < wiphy->bands[band]->n_channels; j++) {
3194 			/* ignore disabled channels */
3195 			if (wiphy->bands[band]->channels[j].flags &
3196 						IEEE80211_CHAN_DISABLED)
3197 				continue;
3198 
3199 			/* If we have a wireless request structure and the
3200 			 * wireless request specifies frequencies, then search
3201 			 * for the matching hardware channel.
3202 			 */
3203 			if (wreq && wreq->num_channels) {
3204 				int k;
3205 				int wiphy_freq = wiphy->bands[band]->channels[j].center_freq;
3206 				for (k = 0; k < wreq->num_channels; k++) {
3207 					struct iw_freq *freq =
3208 						&wreq->channel_list[k];
3209 					int wext_freq =
3210 						cfg80211_wext_freq(freq);
3211 
3212 					if (wext_freq == wiphy_freq)
3213 						goto wext_freq_found;
3214 				}
3215 				goto wext_freq_not_found;
3216 			}
3217 
3218 		wext_freq_found:
3219 			creq->channels[i] = &wiphy->bands[band]->channels[j];
3220 			i++;
3221 		wext_freq_not_found: ;
3222 		}
3223 	}
3224 	/* No channels found? */
3225 	if (!i) {
3226 		err = -EINVAL;
3227 		goto out;
3228 	}
3229 
3230 	/* Set real number of channels specified in creq->channels[] */
3231 	creq->n_channels = i;
3232 
3233 	/* translate "Scan for SSID" request */
3234 	if (wreq) {
3235 		if (wrqu->data.flags & IW_SCAN_THIS_ESSID) {
3236 			if (wreq->essid_len > IEEE80211_MAX_SSID_LEN) {
3237 				err = -EINVAL;
3238 				goto out;
3239 			}
3240 			memcpy(creq->ssids[0].ssid, wreq->essid, wreq->essid_len);
3241 			creq->ssids[0].ssid_len = wreq->essid_len;
3242 		}
3243 		if (wreq->scan_type == IW_SCAN_TYPE_PASSIVE)
3244 			creq->n_ssids = 0;
3245 	}
3246 
3247 	for (i = 0; i < NUM_NL80211_BANDS; i++)
3248 		if (wiphy->bands[i])
3249 			creq->rates[i] = (1 << wiphy->bands[i]->n_bitrates) - 1;
3250 
3251 	eth_broadcast_addr(creq->bssid);
3252 
3253 	wiphy_lock(&rdev->wiphy);
3254 
3255 	rdev->scan_req = creq;
3256 	err = rdev_scan(rdev, creq);
3257 	if (err) {
3258 		rdev->scan_req = NULL;
3259 		/* creq will be freed below */
3260 	} else {
3261 		nl80211_send_scan_start(rdev, dev->ieee80211_ptr);
3262 		/* creq now owned by driver */
3263 		creq = NULL;
3264 		dev_hold(dev);
3265 	}
3266 	wiphy_unlock(&rdev->wiphy);
3267  out:
3268 	kfree(creq);
3269 	return err;
3270 }
3271 EXPORT_WEXT_HANDLER(cfg80211_wext_siwscan);
3272 
3273 static char *ieee80211_scan_add_ies(struct iw_request_info *info,
3274 				    const struct cfg80211_bss_ies *ies,
3275 				    char *current_ev, char *end_buf)
3276 {
3277 	const u8 *pos, *end, *next;
3278 	struct iw_event iwe;
3279 
3280 	if (!ies)
3281 		return current_ev;
3282 
3283 	/*
3284 	 * If needed, fragment the IEs buffer (at IE boundaries) into short
3285 	 * enough fragments to fit into IW_GENERIC_IE_MAX octet messages.
3286 	 */
3287 	pos = ies->data;
3288 	end = pos + ies->len;
3289 
3290 	while (end - pos > IW_GENERIC_IE_MAX) {
3291 		next = pos + 2 + pos[1];
3292 		while (next + 2 + next[1] - pos < IW_GENERIC_IE_MAX)
3293 			next = next + 2 + next[1];
3294 
3295 		memset(&iwe, 0, sizeof(iwe));
3296 		iwe.cmd = IWEVGENIE;
3297 		iwe.u.data.length = next - pos;
3298 		current_ev = iwe_stream_add_point_check(info, current_ev,
3299 							end_buf, &iwe,
3300 							(void *)pos);
3301 		if (IS_ERR(current_ev))
3302 			return current_ev;
3303 		pos = next;
3304 	}
3305 
3306 	if (end > pos) {
3307 		memset(&iwe, 0, sizeof(iwe));
3308 		iwe.cmd = IWEVGENIE;
3309 		iwe.u.data.length = end - pos;
3310 		current_ev = iwe_stream_add_point_check(info, current_ev,
3311 							end_buf, &iwe,
3312 							(void *)pos);
3313 		if (IS_ERR(current_ev))
3314 			return current_ev;
3315 	}
3316 
3317 	return current_ev;
3318 }
3319 
3320 static char *
3321 ieee80211_bss(struct wiphy *wiphy, struct iw_request_info *info,
3322 	      struct cfg80211_internal_bss *bss, char *current_ev,
3323 	      char *end_buf)
3324 {
3325 	const struct cfg80211_bss_ies *ies;
3326 	struct iw_event iwe;
3327 	const u8 *ie;
3328 	u8 buf[50];
3329 	u8 *cfg, *p, *tmp;
3330 	int rem, i, sig;
3331 	bool ismesh = false;
3332 
3333 	memset(&iwe, 0, sizeof(iwe));
3334 	iwe.cmd = SIOCGIWAP;
3335 	iwe.u.ap_addr.sa_family = ARPHRD_ETHER;
3336 	memcpy(iwe.u.ap_addr.sa_data, bss->pub.bssid, ETH_ALEN);
3337 	current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe,
3338 						IW_EV_ADDR_LEN);
3339 	if (IS_ERR(current_ev))
3340 		return current_ev;
3341 
3342 	memset(&iwe, 0, sizeof(iwe));
3343 	iwe.cmd = SIOCGIWFREQ;
3344 	iwe.u.freq.m = ieee80211_frequency_to_channel(bss->pub.channel->center_freq);
3345 	iwe.u.freq.e = 0;
3346 	current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe,
3347 						IW_EV_FREQ_LEN);
3348 	if (IS_ERR(current_ev))
3349 		return current_ev;
3350 
3351 	memset(&iwe, 0, sizeof(iwe));
3352 	iwe.cmd = SIOCGIWFREQ;
3353 	iwe.u.freq.m = bss->pub.channel->center_freq;
3354 	iwe.u.freq.e = 6;
3355 	current_ev = iwe_stream_add_event_check(info, current_ev, end_buf, &iwe,
3356 						IW_EV_FREQ_LEN);
3357 	if (IS_ERR(current_ev))
3358 		return current_ev;
3359 
3360 	if (wiphy->signal_type != CFG80211_SIGNAL_TYPE_NONE) {
3361 		memset(&iwe, 0, sizeof(iwe));
3362 		iwe.cmd = IWEVQUAL;
3363 		iwe.u.qual.updated = IW_QUAL_LEVEL_UPDATED |
3364 				     IW_QUAL_NOISE_INVALID |
3365 				     IW_QUAL_QUAL_UPDATED;
3366 		switch (wiphy->signal_type) {
3367 		case CFG80211_SIGNAL_TYPE_MBM:
3368 			sig = bss->pub.signal / 100;
3369 			iwe.u.qual.level = sig;
3370 			iwe.u.qual.updated |= IW_QUAL_DBM;
3371 			if (sig < -110)		/* rather bad */
3372 				sig = -110;
3373 			else if (sig > -40)	/* perfect */
3374 				sig = -40;
3375 			/* will give a range of 0 .. 70 */
3376 			iwe.u.qual.qual = sig + 110;
3377 			break;
3378 		case CFG80211_SIGNAL_TYPE_UNSPEC:
3379 			iwe.u.qual.level = bss->pub.signal;
3380 			/* will give range 0 .. 100 */
3381 			iwe.u.qual.qual = bss->pub.signal;
3382 			break;
3383 		default:
3384 			/* not reached */
3385 			break;
3386 		}
3387 		current_ev = iwe_stream_add_event_check(info, current_ev,
3388 							end_buf, &iwe,
3389 							IW_EV_QUAL_LEN);
3390 		if (IS_ERR(current_ev))
3391 			return current_ev;
3392 	}
3393 
3394 	memset(&iwe, 0, sizeof(iwe));
3395 	iwe.cmd = SIOCGIWENCODE;
3396 	if (bss->pub.capability & WLAN_CAPABILITY_PRIVACY)
3397 		iwe.u.data.flags = IW_ENCODE_ENABLED | IW_ENCODE_NOKEY;
3398 	else
3399 		iwe.u.data.flags = IW_ENCODE_DISABLED;
3400 	iwe.u.data.length = 0;
3401 	current_ev = iwe_stream_add_point_check(info, current_ev, end_buf,
3402 						&iwe, "");
3403 	if (IS_ERR(current_ev))
3404 		return current_ev;
3405 
3406 	rcu_read_lock();
3407 	ies = rcu_dereference(bss->pub.ies);
3408 	rem = ies->len;
3409 	ie = ies->data;
3410 
3411 	while (rem >= 2) {
3412 		/* invalid data */
3413 		if (ie[1] > rem - 2)
3414 			break;
3415 
3416 		switch (ie[0]) {
3417 		case WLAN_EID_SSID:
3418 			memset(&iwe, 0, sizeof(iwe));
3419 			iwe.cmd = SIOCGIWESSID;
3420 			iwe.u.data.length = ie[1];
3421 			iwe.u.data.flags = 1;
3422 			current_ev = iwe_stream_add_point_check(info,
3423 								current_ev,
3424 								end_buf, &iwe,
3425 								(u8 *)ie + 2);
3426 			if (IS_ERR(current_ev))
3427 				goto unlock;
3428 			break;
3429 		case WLAN_EID_MESH_ID:
3430 			memset(&iwe, 0, sizeof(iwe));
3431 			iwe.cmd = SIOCGIWESSID;
3432 			iwe.u.data.length = ie[1];
3433 			iwe.u.data.flags = 1;
3434 			current_ev = iwe_stream_add_point_check(info,
3435 								current_ev,
3436 								end_buf, &iwe,
3437 								(u8 *)ie + 2);
3438 			if (IS_ERR(current_ev))
3439 				goto unlock;
3440 			break;
3441 		case WLAN_EID_MESH_CONFIG:
3442 			ismesh = true;
3443 			if (ie[1] != sizeof(struct ieee80211_meshconf_ie))
3444 				break;
3445 			cfg = (u8 *)ie + 2;
3446 			memset(&iwe, 0, sizeof(iwe));
3447 			iwe.cmd = IWEVCUSTOM;
3448 			sprintf(buf, "Mesh Network Path Selection Protocol ID: "
3449 				"0x%02X", cfg[0]);
3450 			iwe.u.data.length = strlen(buf);
3451 			current_ev = iwe_stream_add_point_check(info,
3452 								current_ev,
3453 								end_buf,
3454 								&iwe, buf);
3455 			if (IS_ERR(current_ev))
3456 				goto unlock;
3457 			sprintf(buf, "Path Selection Metric ID: 0x%02X",
3458 				cfg[1]);
3459 			iwe.u.data.length = strlen(buf);
3460 			current_ev = iwe_stream_add_point_check(info,
3461 								current_ev,
3462 								end_buf,
3463 								&iwe, buf);
3464 			if (IS_ERR(current_ev))
3465 				goto unlock;
3466 			sprintf(buf, "Congestion Control Mode ID: 0x%02X",
3467 				cfg[2]);
3468 			iwe.u.data.length = strlen(buf);
3469 			current_ev = iwe_stream_add_point_check(info,
3470 								current_ev,
3471 								end_buf,
3472 								&iwe, buf);
3473 			if (IS_ERR(current_ev))
3474 				goto unlock;
3475 			sprintf(buf, "Synchronization ID: 0x%02X", cfg[3]);
3476 			iwe.u.data.length = strlen(buf);
3477 			current_ev = iwe_stream_add_point_check(info,
3478 								current_ev,
3479 								end_buf,
3480 								&iwe, buf);
3481 			if (IS_ERR(current_ev))
3482 				goto unlock;
3483 			sprintf(buf, "Authentication ID: 0x%02X", cfg[4]);
3484 			iwe.u.data.length = strlen(buf);
3485 			current_ev = iwe_stream_add_point_check(info,
3486 								current_ev,
3487 								end_buf,
3488 								&iwe, buf);
3489 			if (IS_ERR(current_ev))
3490 				goto unlock;
3491 			sprintf(buf, "Formation Info: 0x%02X", cfg[5]);
3492 			iwe.u.data.length = strlen(buf);
3493 			current_ev = iwe_stream_add_point_check(info,
3494 								current_ev,
3495 								end_buf,
3496 								&iwe, buf);
3497 			if (IS_ERR(current_ev))
3498 				goto unlock;
3499 			sprintf(buf, "Capabilities: 0x%02X", cfg[6]);
3500 			iwe.u.data.length = strlen(buf);
3501 			current_ev = iwe_stream_add_point_check(info,
3502 								current_ev,
3503 								end_buf,
3504 								&iwe, buf);
3505 			if (IS_ERR(current_ev))
3506 				goto unlock;
3507 			break;
3508 		case WLAN_EID_SUPP_RATES:
3509 		case WLAN_EID_EXT_SUPP_RATES:
3510 			/* display all supported rates in readable format */
3511 			p = current_ev + iwe_stream_lcp_len(info);
3512 
3513 			memset(&iwe, 0, sizeof(iwe));
3514 			iwe.cmd = SIOCGIWRATE;
3515 			/* Those two flags are ignored... */
3516 			iwe.u.bitrate.fixed = iwe.u.bitrate.disabled = 0;
3517 
3518 			for (i = 0; i < ie[1]; i++) {
3519 				iwe.u.bitrate.value =
3520 					((ie[i + 2] & 0x7f) * 500000);
3521 				tmp = p;
3522 				p = iwe_stream_add_value(info, current_ev, p,
3523 							 end_buf, &iwe,
3524 							 IW_EV_PARAM_LEN);
3525 				if (p == tmp) {
3526 					current_ev = ERR_PTR(-E2BIG);
3527 					goto unlock;
3528 				}
3529 			}
3530 			current_ev = p;
3531 			break;
3532 		}
3533 		rem -= ie[1] + 2;
3534 		ie += ie[1] + 2;
3535 	}
3536 
3537 	if (bss->pub.capability & (WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS) ||
3538 	    ismesh) {
3539 		memset(&iwe, 0, sizeof(iwe));
3540 		iwe.cmd = SIOCGIWMODE;
3541 		if (ismesh)
3542 			iwe.u.mode = IW_MODE_MESH;
3543 		else if (bss->pub.capability & WLAN_CAPABILITY_ESS)
3544 			iwe.u.mode = IW_MODE_MASTER;
3545 		else
3546 			iwe.u.mode = IW_MODE_ADHOC;
3547 		current_ev = iwe_stream_add_event_check(info, current_ev,
3548 							end_buf, &iwe,
3549 							IW_EV_UINT_LEN);
3550 		if (IS_ERR(current_ev))
3551 			goto unlock;
3552 	}
3553 
3554 	memset(&iwe, 0, sizeof(iwe));
3555 	iwe.cmd = IWEVCUSTOM;
3556 	sprintf(buf, "tsf=%016llx", (unsigned long long)(ies->tsf));
3557 	iwe.u.data.length = strlen(buf);
3558 	current_ev = iwe_stream_add_point_check(info, current_ev, end_buf,
3559 						&iwe, buf);
3560 	if (IS_ERR(current_ev))
3561 		goto unlock;
3562 	memset(&iwe, 0, sizeof(iwe));
3563 	iwe.cmd = IWEVCUSTOM;
3564 	sprintf(buf, " Last beacon: %ums ago",
3565 		elapsed_jiffies_msecs(bss->ts));
3566 	iwe.u.data.length = strlen(buf);
3567 	current_ev = iwe_stream_add_point_check(info, current_ev,
3568 						end_buf, &iwe, buf);
3569 	if (IS_ERR(current_ev))
3570 		goto unlock;
3571 
3572 	current_ev = ieee80211_scan_add_ies(info, ies, current_ev, end_buf);
3573 
3574  unlock:
3575 	rcu_read_unlock();
3576 	return current_ev;
3577 }
3578 
3579 
3580 static int ieee80211_scan_results(struct cfg80211_registered_device *rdev,
3581 				  struct iw_request_info *info,
3582 				  char *buf, size_t len)
3583 {
3584 	char *current_ev = buf;
3585 	char *end_buf = buf + len;
3586 	struct cfg80211_internal_bss *bss;
3587 	int err = 0;
3588 
3589 	spin_lock_bh(&rdev->bss_lock);
3590 	cfg80211_bss_expire(rdev);
3591 
3592 	list_for_each_entry(bss, &rdev->bss_list, list) {
3593 		if (buf + len - current_ev <= IW_EV_ADDR_LEN) {
3594 			err = -E2BIG;
3595 			break;
3596 		}
3597 		current_ev = ieee80211_bss(&rdev->wiphy, info, bss,
3598 					   current_ev, end_buf);
3599 		if (IS_ERR(current_ev)) {
3600 			err = PTR_ERR(current_ev);
3601 			break;
3602 		}
3603 	}
3604 	spin_unlock_bh(&rdev->bss_lock);
3605 
3606 	if (err)
3607 		return err;
3608 	return current_ev - buf;
3609 }
3610 
3611 
3612 int cfg80211_wext_giwscan(struct net_device *dev,
3613 			  struct iw_request_info *info,
3614 			  union iwreq_data *wrqu, char *extra)
3615 {
3616 	struct iw_point *data = &wrqu->data;
3617 	struct cfg80211_registered_device *rdev;
3618 	int res;
3619 
3620 	if (!netif_running(dev))
3621 		return -ENETDOWN;
3622 
3623 	rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
3624 
3625 	if (IS_ERR(rdev))
3626 		return PTR_ERR(rdev);
3627 
3628 	if (rdev->scan_req || rdev->scan_msg)
3629 		return -EAGAIN;
3630 
3631 	res = ieee80211_scan_results(rdev, info, extra, data->length);
3632 	data->length = 0;
3633 	if (res >= 0) {
3634 		data->length = res;
3635 		res = 0;
3636 	}
3637 
3638 	return res;
3639 }
3640 EXPORT_WEXT_HANDLER(cfg80211_wext_giwscan);
3641 #endif
3642