xref: /openbmc/linux/net/mac80211/rx.c (revision 036b9e7c)
1 /*
2  * Copyright 2002-2005, Instant802 Networks, Inc.
3  * Copyright 2005-2006, Devicescape Software, Inc.
4  * Copyright 2006-2007	Jiri Benc <jbenc@suse.cz>
5  * Copyright 2007-2010	Johannes Berg <johannes@sipsolutions.net>
6  * Copyright 2013-2014  Intel Mobile Communications GmbH
7  * Copyright(c) 2015 - 2017 Intel Deutschland GmbH
8  * Copyright (C) 2018 Intel Corporation
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License version 2 as
12  * published by the Free Software Foundation.
13  */
14 
15 #include <linux/jiffies.h>
16 #include <linux/slab.h>
17 #include <linux/kernel.h>
18 #include <linux/skbuff.h>
19 #include <linux/netdevice.h>
20 #include <linux/etherdevice.h>
21 #include <linux/rcupdate.h>
22 #include <linux/export.h>
23 #include <linux/bitops.h>
24 #include <net/mac80211.h>
25 #include <net/ieee80211_radiotap.h>
26 #include <asm/unaligned.h>
27 
28 #include "ieee80211_i.h"
29 #include "driver-ops.h"
30 #include "led.h"
31 #include "mesh.h"
32 #include "wep.h"
33 #include "wpa.h"
34 #include "tkip.h"
35 #include "wme.h"
36 #include "rate.h"
37 
38 static inline void ieee80211_rx_stats(struct net_device *dev, u32 len)
39 {
40 	struct pcpu_sw_netstats *tstats = this_cpu_ptr(dev->tstats);
41 
42 	u64_stats_update_begin(&tstats->syncp);
43 	tstats->rx_packets++;
44 	tstats->rx_bytes += len;
45 	u64_stats_update_end(&tstats->syncp);
46 }
47 
48 static u8 *ieee80211_get_bssid(struct ieee80211_hdr *hdr, size_t len,
49 			       enum nl80211_iftype type)
50 {
51 	__le16 fc = hdr->frame_control;
52 
53 	if (ieee80211_is_data(fc)) {
54 		if (len < 24) /* drop incorrect hdr len (data) */
55 			return NULL;
56 
57 		if (ieee80211_has_a4(fc))
58 			return NULL;
59 		if (ieee80211_has_tods(fc))
60 			return hdr->addr1;
61 		if (ieee80211_has_fromds(fc))
62 			return hdr->addr2;
63 
64 		return hdr->addr3;
65 	}
66 
67 	if (ieee80211_is_mgmt(fc)) {
68 		if (len < 24) /* drop incorrect hdr len (mgmt) */
69 			return NULL;
70 		return hdr->addr3;
71 	}
72 
73 	if (ieee80211_is_ctl(fc)) {
74 		if (ieee80211_is_pspoll(fc))
75 			return hdr->addr1;
76 
77 		if (ieee80211_is_back_req(fc)) {
78 			switch (type) {
79 			case NL80211_IFTYPE_STATION:
80 				return hdr->addr2;
81 			case NL80211_IFTYPE_AP:
82 			case NL80211_IFTYPE_AP_VLAN:
83 				return hdr->addr1;
84 			default:
85 				break; /* fall through to the return */
86 			}
87 		}
88 	}
89 
90 	return NULL;
91 }
92 
93 /*
94  * monitor mode reception
95  *
96  * This function cleans up the SKB, i.e. it removes all the stuff
97  * only useful for monitoring.
98  */
99 static void remove_monitor_info(struct sk_buff *skb,
100 				unsigned int present_fcs_len,
101 				unsigned int rtap_space)
102 {
103 	if (present_fcs_len)
104 		__pskb_trim(skb, skb->len - present_fcs_len);
105 	__pskb_pull(skb, rtap_space);
106 }
107 
108 static inline bool should_drop_frame(struct sk_buff *skb, int present_fcs_len,
109 				     unsigned int rtap_space)
110 {
111 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
112 	struct ieee80211_hdr *hdr;
113 
114 	hdr = (void *)(skb->data + rtap_space);
115 
116 	if (status->flag & (RX_FLAG_FAILED_FCS_CRC |
117 			    RX_FLAG_FAILED_PLCP_CRC |
118 			    RX_FLAG_ONLY_MONITOR |
119 			    RX_FLAG_NO_PSDU))
120 		return true;
121 
122 	if (unlikely(skb->len < 16 + present_fcs_len + rtap_space))
123 		return true;
124 
125 	if (ieee80211_is_ctl(hdr->frame_control) &&
126 	    !ieee80211_is_pspoll(hdr->frame_control) &&
127 	    !ieee80211_is_back_req(hdr->frame_control))
128 		return true;
129 
130 	return false;
131 }
132 
133 static int
134 ieee80211_rx_radiotap_hdrlen(struct ieee80211_local *local,
135 			     struct ieee80211_rx_status *status,
136 			     struct sk_buff *skb)
137 {
138 	int len;
139 
140 	/* always present fields */
141 	len = sizeof(struct ieee80211_radiotap_header) + 8;
142 
143 	/* allocate extra bitmaps */
144 	if (status->chains)
145 		len += 4 * hweight8(status->chains);
146 
147 	if (ieee80211_have_rx_timestamp(status)) {
148 		len = ALIGN(len, 8);
149 		len += 8;
150 	}
151 	if (ieee80211_hw_check(&local->hw, SIGNAL_DBM))
152 		len += 1;
153 
154 	/* antenna field, if we don't have per-chain info */
155 	if (!status->chains)
156 		len += 1;
157 
158 	/* padding for RX_FLAGS if necessary */
159 	len = ALIGN(len, 2);
160 
161 	if (status->encoding == RX_ENC_HT) /* HT info */
162 		len += 3;
163 
164 	if (status->flag & RX_FLAG_AMPDU_DETAILS) {
165 		len = ALIGN(len, 4);
166 		len += 8;
167 	}
168 
169 	if (status->encoding == RX_ENC_VHT) {
170 		len = ALIGN(len, 2);
171 		len += 12;
172 	}
173 
174 	if (local->hw.radiotap_timestamp.units_pos >= 0) {
175 		len = ALIGN(len, 8);
176 		len += 12;
177 	}
178 
179 	if (status->encoding == RX_ENC_HE &&
180 	    status->flag & RX_FLAG_RADIOTAP_HE) {
181 		len = ALIGN(len, 2);
182 		len += 12;
183 		BUILD_BUG_ON(sizeof(struct ieee80211_radiotap_he) != 12);
184 	}
185 
186 	if (status->encoding == RX_ENC_HE &&
187 	    status->flag & RX_FLAG_RADIOTAP_HE_MU) {
188 		len = ALIGN(len, 2);
189 		len += 12;
190 		BUILD_BUG_ON(sizeof(struct ieee80211_radiotap_he_mu) != 12);
191 	}
192 
193 	if (status->flag & RX_FLAG_NO_PSDU)
194 		len += 1;
195 
196 	if (status->flag & RX_FLAG_RADIOTAP_LSIG) {
197 		len = ALIGN(len, 2);
198 		len += 4;
199 		BUILD_BUG_ON(sizeof(struct ieee80211_radiotap_lsig) != 4);
200 	}
201 
202 	if (status->chains) {
203 		/* antenna and antenna signal fields */
204 		len += 2 * hweight8(status->chains);
205 	}
206 
207 	if (status->flag & RX_FLAG_RADIOTAP_VENDOR_DATA) {
208 		struct ieee80211_vendor_radiotap *rtap = (void *)skb->data;
209 
210 		/* vendor presence bitmap */
211 		len += 4;
212 		/* alignment for fixed 6-byte vendor data header */
213 		len = ALIGN(len, 2);
214 		/* vendor data header */
215 		len += 6;
216 		if (WARN_ON(rtap->align == 0))
217 			rtap->align = 1;
218 		len = ALIGN(len, rtap->align);
219 		len += rtap->len + rtap->pad;
220 	}
221 
222 	return len;
223 }
224 
225 static void ieee80211_handle_mu_mimo_mon(struct ieee80211_sub_if_data *sdata,
226 					 struct sk_buff *skb,
227 					 int rtap_space)
228 {
229 	struct {
230 		struct ieee80211_hdr_3addr hdr;
231 		u8 category;
232 		u8 action_code;
233 	} __packed action;
234 
235 	if (!sdata)
236 		return;
237 
238 	BUILD_BUG_ON(sizeof(action) != IEEE80211_MIN_ACTION_SIZE + 1);
239 
240 	if (skb->len < rtap_space + sizeof(action) +
241 		       VHT_MUMIMO_GROUPS_DATA_LEN)
242 		return;
243 
244 	if (!is_valid_ether_addr(sdata->u.mntr.mu_follow_addr))
245 		return;
246 
247 	skb_copy_bits(skb, rtap_space, &action, sizeof(action));
248 
249 	if (!ieee80211_is_action(action.hdr.frame_control))
250 		return;
251 
252 	if (action.category != WLAN_CATEGORY_VHT)
253 		return;
254 
255 	if (action.action_code != WLAN_VHT_ACTION_GROUPID_MGMT)
256 		return;
257 
258 	if (!ether_addr_equal(action.hdr.addr1, sdata->u.mntr.mu_follow_addr))
259 		return;
260 
261 	skb = skb_copy(skb, GFP_ATOMIC);
262 	if (!skb)
263 		return;
264 
265 	skb_queue_tail(&sdata->skb_queue, skb);
266 	ieee80211_queue_work(&sdata->local->hw, &sdata->work);
267 }
268 
269 /*
270  * ieee80211_add_rx_radiotap_header - add radiotap header
271  *
272  * add a radiotap header containing all the fields which the hardware provided.
273  */
274 static void
275 ieee80211_add_rx_radiotap_header(struct ieee80211_local *local,
276 				 struct sk_buff *skb,
277 				 struct ieee80211_rate *rate,
278 				 int rtap_len, bool has_fcs)
279 {
280 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
281 	struct ieee80211_radiotap_header *rthdr;
282 	unsigned char *pos;
283 	__le32 *it_present;
284 	u32 it_present_val;
285 	u16 rx_flags = 0;
286 	u16 channel_flags = 0;
287 	int mpdulen, chain;
288 	unsigned long chains = status->chains;
289 	struct ieee80211_vendor_radiotap rtap = {};
290 	struct ieee80211_radiotap_he he = {};
291 	struct ieee80211_radiotap_he_mu he_mu = {};
292 	struct ieee80211_radiotap_lsig lsig = {};
293 
294 	if (status->flag & RX_FLAG_RADIOTAP_HE) {
295 		he = *(struct ieee80211_radiotap_he *)skb->data;
296 		skb_pull(skb, sizeof(he));
297 		WARN_ON_ONCE(status->encoding != RX_ENC_HE);
298 	}
299 
300 	if (status->flag & RX_FLAG_RADIOTAP_HE_MU) {
301 		he_mu = *(struct ieee80211_radiotap_he_mu *)skb->data;
302 		skb_pull(skb, sizeof(he_mu));
303 	}
304 
305 	if (status->flag & RX_FLAG_RADIOTAP_LSIG) {
306 		lsig = *(struct ieee80211_radiotap_lsig *)skb->data;
307 		skb_pull(skb, sizeof(lsig));
308 	}
309 
310 	if (status->flag & RX_FLAG_RADIOTAP_VENDOR_DATA) {
311 		rtap = *(struct ieee80211_vendor_radiotap *)skb->data;
312 		/* rtap.len and rtap.pad are undone immediately */
313 		skb_pull(skb, sizeof(rtap) + rtap.len + rtap.pad);
314 	}
315 
316 	mpdulen = skb->len;
317 	if (!(has_fcs && ieee80211_hw_check(&local->hw, RX_INCLUDES_FCS)))
318 		mpdulen += FCS_LEN;
319 
320 	rthdr = skb_push(skb, rtap_len);
321 	memset(rthdr, 0, rtap_len - rtap.len - rtap.pad);
322 	it_present = &rthdr->it_present;
323 
324 	/* radiotap header, set always present flags */
325 	rthdr->it_len = cpu_to_le16(rtap_len);
326 	it_present_val = BIT(IEEE80211_RADIOTAP_FLAGS) |
327 			 BIT(IEEE80211_RADIOTAP_CHANNEL) |
328 			 BIT(IEEE80211_RADIOTAP_RX_FLAGS);
329 
330 	if (!status->chains)
331 		it_present_val |= BIT(IEEE80211_RADIOTAP_ANTENNA);
332 
333 	for_each_set_bit(chain, &chains, IEEE80211_MAX_CHAINS) {
334 		it_present_val |=
335 			BIT(IEEE80211_RADIOTAP_EXT) |
336 			BIT(IEEE80211_RADIOTAP_RADIOTAP_NAMESPACE);
337 		put_unaligned_le32(it_present_val, it_present);
338 		it_present++;
339 		it_present_val = BIT(IEEE80211_RADIOTAP_ANTENNA) |
340 				 BIT(IEEE80211_RADIOTAP_DBM_ANTSIGNAL);
341 	}
342 
343 	if (status->flag & RX_FLAG_RADIOTAP_VENDOR_DATA) {
344 		it_present_val |= BIT(IEEE80211_RADIOTAP_VENDOR_NAMESPACE) |
345 				  BIT(IEEE80211_RADIOTAP_EXT);
346 		put_unaligned_le32(it_present_val, it_present);
347 		it_present++;
348 		it_present_val = rtap.present;
349 	}
350 
351 	put_unaligned_le32(it_present_val, it_present);
352 
353 	pos = (void *)(it_present + 1);
354 
355 	/* the order of the following fields is important */
356 
357 	/* IEEE80211_RADIOTAP_TSFT */
358 	if (ieee80211_have_rx_timestamp(status)) {
359 		/* padding */
360 		while ((pos - (u8 *)rthdr) & 7)
361 			*pos++ = 0;
362 		put_unaligned_le64(
363 			ieee80211_calculate_rx_timestamp(local, status,
364 							 mpdulen, 0),
365 			pos);
366 		rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_TSFT);
367 		pos += 8;
368 	}
369 
370 	/* IEEE80211_RADIOTAP_FLAGS */
371 	if (has_fcs && ieee80211_hw_check(&local->hw, RX_INCLUDES_FCS))
372 		*pos |= IEEE80211_RADIOTAP_F_FCS;
373 	if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
374 		*pos |= IEEE80211_RADIOTAP_F_BADFCS;
375 	if (status->enc_flags & RX_ENC_FLAG_SHORTPRE)
376 		*pos |= IEEE80211_RADIOTAP_F_SHORTPRE;
377 	pos++;
378 
379 	/* IEEE80211_RADIOTAP_RATE */
380 	if (!rate || status->encoding != RX_ENC_LEGACY) {
381 		/*
382 		 * Without rate information don't add it. If we have,
383 		 * MCS information is a separate field in radiotap,
384 		 * added below. The byte here is needed as padding
385 		 * for the channel though, so initialise it to 0.
386 		 */
387 		*pos = 0;
388 	} else {
389 		int shift = 0;
390 		rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
391 		if (status->bw == RATE_INFO_BW_10)
392 			shift = 1;
393 		else if (status->bw == RATE_INFO_BW_5)
394 			shift = 2;
395 		*pos = DIV_ROUND_UP(rate->bitrate, 5 * (1 << shift));
396 	}
397 	pos++;
398 
399 	/* IEEE80211_RADIOTAP_CHANNEL */
400 	put_unaligned_le16(status->freq, pos);
401 	pos += 2;
402 	if (status->bw == RATE_INFO_BW_10)
403 		channel_flags |= IEEE80211_CHAN_HALF;
404 	else if (status->bw == RATE_INFO_BW_5)
405 		channel_flags |= IEEE80211_CHAN_QUARTER;
406 
407 	if (status->band == NL80211_BAND_5GHZ)
408 		channel_flags |= IEEE80211_CHAN_OFDM | IEEE80211_CHAN_5GHZ;
409 	else if (status->encoding != RX_ENC_LEGACY)
410 		channel_flags |= IEEE80211_CHAN_DYN | IEEE80211_CHAN_2GHZ;
411 	else if (rate && rate->flags & IEEE80211_RATE_ERP_G)
412 		channel_flags |= IEEE80211_CHAN_OFDM | IEEE80211_CHAN_2GHZ;
413 	else if (rate)
414 		channel_flags |= IEEE80211_CHAN_CCK | IEEE80211_CHAN_2GHZ;
415 	else
416 		channel_flags |= IEEE80211_CHAN_2GHZ;
417 	put_unaligned_le16(channel_flags, pos);
418 	pos += 2;
419 
420 	/* IEEE80211_RADIOTAP_DBM_ANTSIGNAL */
421 	if (ieee80211_hw_check(&local->hw, SIGNAL_DBM) &&
422 	    !(status->flag & RX_FLAG_NO_SIGNAL_VAL)) {
423 		*pos = status->signal;
424 		rthdr->it_present |=
425 			cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTSIGNAL);
426 		pos++;
427 	}
428 
429 	/* IEEE80211_RADIOTAP_LOCK_QUALITY is missing */
430 
431 	if (!status->chains) {
432 		/* IEEE80211_RADIOTAP_ANTENNA */
433 		*pos = status->antenna;
434 		pos++;
435 	}
436 
437 	/* IEEE80211_RADIOTAP_DB_ANTNOISE is not used */
438 
439 	/* IEEE80211_RADIOTAP_RX_FLAGS */
440 	/* ensure 2 byte alignment for the 2 byte field as required */
441 	if ((pos - (u8 *)rthdr) & 1)
442 		*pos++ = 0;
443 	if (status->flag & RX_FLAG_FAILED_PLCP_CRC)
444 		rx_flags |= IEEE80211_RADIOTAP_F_RX_BADPLCP;
445 	put_unaligned_le16(rx_flags, pos);
446 	pos += 2;
447 
448 	if (status->encoding == RX_ENC_HT) {
449 		unsigned int stbc;
450 
451 		rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_MCS);
452 		*pos++ = local->hw.radiotap_mcs_details;
453 		*pos = 0;
454 		if (status->enc_flags & RX_ENC_FLAG_SHORT_GI)
455 			*pos |= IEEE80211_RADIOTAP_MCS_SGI;
456 		if (status->bw == RATE_INFO_BW_40)
457 			*pos |= IEEE80211_RADIOTAP_MCS_BW_40;
458 		if (status->enc_flags & RX_ENC_FLAG_HT_GF)
459 			*pos |= IEEE80211_RADIOTAP_MCS_FMT_GF;
460 		if (status->enc_flags & RX_ENC_FLAG_LDPC)
461 			*pos |= IEEE80211_RADIOTAP_MCS_FEC_LDPC;
462 		stbc = (status->enc_flags & RX_ENC_FLAG_STBC_MASK) >> RX_ENC_FLAG_STBC_SHIFT;
463 		*pos |= stbc << IEEE80211_RADIOTAP_MCS_STBC_SHIFT;
464 		pos++;
465 		*pos++ = status->rate_idx;
466 	}
467 
468 	if (status->flag & RX_FLAG_AMPDU_DETAILS) {
469 		u16 flags = 0;
470 
471 		/* ensure 4 byte alignment */
472 		while ((pos - (u8 *)rthdr) & 3)
473 			pos++;
474 		rthdr->it_present |=
475 			cpu_to_le32(1 << IEEE80211_RADIOTAP_AMPDU_STATUS);
476 		put_unaligned_le32(status->ampdu_reference, pos);
477 		pos += 4;
478 		if (status->flag & RX_FLAG_AMPDU_LAST_KNOWN)
479 			flags |= IEEE80211_RADIOTAP_AMPDU_LAST_KNOWN;
480 		if (status->flag & RX_FLAG_AMPDU_IS_LAST)
481 			flags |= IEEE80211_RADIOTAP_AMPDU_IS_LAST;
482 		if (status->flag & RX_FLAG_AMPDU_DELIM_CRC_ERROR)
483 			flags |= IEEE80211_RADIOTAP_AMPDU_DELIM_CRC_ERR;
484 		if (status->flag & RX_FLAG_AMPDU_DELIM_CRC_KNOWN)
485 			flags |= IEEE80211_RADIOTAP_AMPDU_DELIM_CRC_KNOWN;
486 		if (status->flag & RX_FLAG_AMPDU_EOF_BIT_KNOWN)
487 			flags |= IEEE80211_RADIOTAP_AMPDU_EOF_KNOWN;
488 		if (status->flag & RX_FLAG_AMPDU_EOF_BIT)
489 			flags |= IEEE80211_RADIOTAP_AMPDU_EOF;
490 		put_unaligned_le16(flags, pos);
491 		pos += 2;
492 		if (status->flag & RX_FLAG_AMPDU_DELIM_CRC_KNOWN)
493 			*pos++ = status->ampdu_delimiter_crc;
494 		else
495 			*pos++ = 0;
496 		*pos++ = 0;
497 	}
498 
499 	if (status->encoding == RX_ENC_VHT) {
500 		u16 known = local->hw.radiotap_vht_details;
501 
502 		rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_VHT);
503 		put_unaligned_le16(known, pos);
504 		pos += 2;
505 		/* flags */
506 		if (status->enc_flags & RX_ENC_FLAG_SHORT_GI)
507 			*pos |= IEEE80211_RADIOTAP_VHT_FLAG_SGI;
508 		/* in VHT, STBC is binary */
509 		if (status->enc_flags & RX_ENC_FLAG_STBC_MASK)
510 			*pos |= IEEE80211_RADIOTAP_VHT_FLAG_STBC;
511 		if (status->enc_flags & RX_ENC_FLAG_BF)
512 			*pos |= IEEE80211_RADIOTAP_VHT_FLAG_BEAMFORMED;
513 		pos++;
514 		/* bandwidth */
515 		switch (status->bw) {
516 		case RATE_INFO_BW_80:
517 			*pos++ = 4;
518 			break;
519 		case RATE_INFO_BW_160:
520 			*pos++ = 11;
521 			break;
522 		case RATE_INFO_BW_40:
523 			*pos++ = 1;
524 			break;
525 		default:
526 			*pos++ = 0;
527 		}
528 		/* MCS/NSS */
529 		*pos = (status->rate_idx << 4) | status->nss;
530 		pos += 4;
531 		/* coding field */
532 		if (status->enc_flags & RX_ENC_FLAG_LDPC)
533 			*pos |= IEEE80211_RADIOTAP_CODING_LDPC_USER0;
534 		pos++;
535 		/* group ID */
536 		pos++;
537 		/* partial_aid */
538 		pos += 2;
539 	}
540 
541 	if (local->hw.radiotap_timestamp.units_pos >= 0) {
542 		u16 accuracy = 0;
543 		u8 flags = IEEE80211_RADIOTAP_TIMESTAMP_FLAG_32BIT;
544 
545 		rthdr->it_present |=
546 			cpu_to_le32(1 << IEEE80211_RADIOTAP_TIMESTAMP);
547 
548 		/* ensure 8 byte alignment */
549 		while ((pos - (u8 *)rthdr) & 7)
550 			pos++;
551 
552 		put_unaligned_le64(status->device_timestamp, pos);
553 		pos += sizeof(u64);
554 
555 		if (local->hw.radiotap_timestamp.accuracy >= 0) {
556 			accuracy = local->hw.radiotap_timestamp.accuracy;
557 			flags |= IEEE80211_RADIOTAP_TIMESTAMP_FLAG_ACCURACY;
558 		}
559 		put_unaligned_le16(accuracy, pos);
560 		pos += sizeof(u16);
561 
562 		*pos++ = local->hw.radiotap_timestamp.units_pos;
563 		*pos++ = flags;
564 	}
565 
566 	if (status->encoding == RX_ENC_HE &&
567 	    status->flag & RX_FLAG_RADIOTAP_HE) {
568 #define HE_PREP(f, val)	le16_encode_bits(val, IEEE80211_RADIOTAP_HE_##f)
569 
570 		if (status->enc_flags & RX_ENC_FLAG_STBC_MASK) {
571 			he.data6 |= HE_PREP(DATA6_NSTS,
572 					    FIELD_GET(RX_ENC_FLAG_STBC_MASK,
573 						      status->enc_flags));
574 			he.data3 |= HE_PREP(DATA3_STBC, 1);
575 		} else {
576 			he.data6 |= HE_PREP(DATA6_NSTS, status->nss);
577 		}
578 
579 #define CHECK_GI(s) \
580 	BUILD_BUG_ON(IEEE80211_RADIOTAP_HE_DATA5_GI_##s != \
581 		     (int)NL80211_RATE_INFO_HE_GI_##s)
582 
583 		CHECK_GI(0_8);
584 		CHECK_GI(1_6);
585 		CHECK_GI(3_2);
586 
587 		he.data3 |= HE_PREP(DATA3_DATA_MCS, status->rate_idx);
588 		he.data3 |= HE_PREP(DATA3_DATA_DCM, status->he_dcm);
589 		he.data3 |= HE_PREP(DATA3_CODING,
590 				    !!(status->enc_flags & RX_ENC_FLAG_LDPC));
591 
592 		he.data5 |= HE_PREP(DATA5_GI, status->he_gi);
593 
594 		switch (status->bw) {
595 		case RATE_INFO_BW_20:
596 			he.data5 |= HE_PREP(DATA5_DATA_BW_RU_ALLOC,
597 					    IEEE80211_RADIOTAP_HE_DATA5_DATA_BW_RU_ALLOC_20MHZ);
598 			break;
599 		case RATE_INFO_BW_40:
600 			he.data5 |= HE_PREP(DATA5_DATA_BW_RU_ALLOC,
601 					    IEEE80211_RADIOTAP_HE_DATA5_DATA_BW_RU_ALLOC_40MHZ);
602 			break;
603 		case RATE_INFO_BW_80:
604 			he.data5 |= HE_PREP(DATA5_DATA_BW_RU_ALLOC,
605 					    IEEE80211_RADIOTAP_HE_DATA5_DATA_BW_RU_ALLOC_80MHZ);
606 			break;
607 		case RATE_INFO_BW_160:
608 			he.data5 |= HE_PREP(DATA5_DATA_BW_RU_ALLOC,
609 					    IEEE80211_RADIOTAP_HE_DATA5_DATA_BW_RU_ALLOC_160MHZ);
610 			break;
611 		case RATE_INFO_BW_HE_RU:
612 #define CHECK_RU_ALLOC(s) \
613 	BUILD_BUG_ON(IEEE80211_RADIOTAP_HE_DATA5_DATA_BW_RU_ALLOC_##s##T != \
614 		     NL80211_RATE_INFO_HE_RU_ALLOC_##s + 4)
615 
616 			CHECK_RU_ALLOC(26);
617 			CHECK_RU_ALLOC(52);
618 			CHECK_RU_ALLOC(106);
619 			CHECK_RU_ALLOC(242);
620 			CHECK_RU_ALLOC(484);
621 			CHECK_RU_ALLOC(996);
622 			CHECK_RU_ALLOC(2x996);
623 
624 			he.data5 |= HE_PREP(DATA5_DATA_BW_RU_ALLOC,
625 					    status->he_ru + 4);
626 			break;
627 		default:
628 			WARN_ONCE(1, "Invalid SU BW %d\n", status->bw);
629 		}
630 
631 		/* ensure 2 byte alignment */
632 		while ((pos - (u8 *)rthdr) & 1)
633 			pos++;
634 		rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_HE);
635 		memcpy(pos, &he, sizeof(he));
636 		pos += sizeof(he);
637 	}
638 
639 	if (status->encoding == RX_ENC_HE &&
640 	    status->flag & RX_FLAG_RADIOTAP_HE_MU) {
641 		/* ensure 2 byte alignment */
642 		while ((pos - (u8 *)rthdr) & 1)
643 			pos++;
644 		rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_HE_MU);
645 		memcpy(pos, &he_mu, sizeof(he_mu));
646 		pos += sizeof(he_mu);
647 	}
648 
649 	if (status->flag & RX_FLAG_NO_PSDU) {
650 		rthdr->it_present |=
651 			cpu_to_le32(1 << IEEE80211_RADIOTAP_ZERO_LEN_PSDU);
652 		*pos++ = status->zero_length_psdu_type;
653 	}
654 
655 	if (status->flag & RX_FLAG_RADIOTAP_LSIG) {
656 		/* ensure 2 byte alignment */
657 		while ((pos - (u8 *)rthdr) & 1)
658 			pos++;
659 		rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_LSIG);
660 		memcpy(pos, &lsig, sizeof(lsig));
661 		pos += sizeof(lsig);
662 	}
663 
664 	for_each_set_bit(chain, &chains, IEEE80211_MAX_CHAINS) {
665 		*pos++ = status->chain_signal[chain];
666 		*pos++ = chain;
667 	}
668 
669 	if (status->flag & RX_FLAG_RADIOTAP_VENDOR_DATA) {
670 		/* ensure 2 byte alignment for the vendor field as required */
671 		if ((pos - (u8 *)rthdr) & 1)
672 			*pos++ = 0;
673 		*pos++ = rtap.oui[0];
674 		*pos++ = rtap.oui[1];
675 		*pos++ = rtap.oui[2];
676 		*pos++ = rtap.subns;
677 		put_unaligned_le16(rtap.len, pos);
678 		pos += 2;
679 		/* align the actual payload as requested */
680 		while ((pos - (u8 *)rthdr) & (rtap.align - 1))
681 			*pos++ = 0;
682 		/* data (and possible padding) already follows */
683 	}
684 }
685 
686 static struct sk_buff *
687 ieee80211_make_monitor_skb(struct ieee80211_local *local,
688 			   struct sk_buff **origskb,
689 			   struct ieee80211_rate *rate,
690 			   int rtap_space, bool use_origskb)
691 {
692 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(*origskb);
693 	int rt_hdrlen, needed_headroom;
694 	struct sk_buff *skb;
695 
696 	/* room for the radiotap header based on driver features */
697 	rt_hdrlen = ieee80211_rx_radiotap_hdrlen(local, status, *origskb);
698 	needed_headroom = rt_hdrlen - rtap_space;
699 
700 	if (use_origskb) {
701 		/* only need to expand headroom if necessary */
702 		skb = *origskb;
703 		*origskb = NULL;
704 
705 		/*
706 		 * This shouldn't trigger often because most devices have an
707 		 * RX header they pull before we get here, and that should
708 		 * be big enough for our radiotap information. We should
709 		 * probably export the length to drivers so that we can have
710 		 * them allocate enough headroom to start with.
711 		 */
712 		if (skb_headroom(skb) < needed_headroom &&
713 		    pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC)) {
714 			dev_kfree_skb(skb);
715 			return NULL;
716 		}
717 	} else {
718 		/*
719 		 * Need to make a copy and possibly remove radiotap header
720 		 * and FCS from the original.
721 		 */
722 		skb = skb_copy_expand(*origskb, needed_headroom, 0, GFP_ATOMIC);
723 
724 		if (!skb)
725 			return NULL;
726 	}
727 
728 	/* prepend radiotap information */
729 	ieee80211_add_rx_radiotap_header(local, skb, rate, rt_hdrlen, true);
730 
731 	skb_reset_mac_header(skb);
732 	skb->ip_summed = CHECKSUM_UNNECESSARY;
733 	skb->pkt_type = PACKET_OTHERHOST;
734 	skb->protocol = htons(ETH_P_802_2);
735 
736 	return skb;
737 }
738 
739 /*
740  * This function copies a received frame to all monitor interfaces and
741  * returns a cleaned-up SKB that no longer includes the FCS nor the
742  * radiotap header the driver might have added.
743  */
744 static struct sk_buff *
745 ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb,
746 		     struct ieee80211_rate *rate)
747 {
748 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(origskb);
749 	struct ieee80211_sub_if_data *sdata;
750 	struct sk_buff *monskb = NULL;
751 	int present_fcs_len = 0;
752 	unsigned int rtap_space = 0;
753 	struct ieee80211_sub_if_data *monitor_sdata =
754 		rcu_dereference(local->monitor_sdata);
755 	bool only_monitor = false;
756 
757 	if (status->flag & RX_FLAG_RADIOTAP_HE)
758 		rtap_space += sizeof(struct ieee80211_radiotap_he);
759 
760 	if (status->flag & RX_FLAG_RADIOTAP_HE_MU)
761 		rtap_space += sizeof(struct ieee80211_radiotap_he_mu);
762 
763 	if (unlikely(status->flag & RX_FLAG_RADIOTAP_VENDOR_DATA)) {
764 		struct ieee80211_vendor_radiotap *rtap = (void *)origskb->data;
765 
766 		rtap_space += sizeof(*rtap) + rtap->len + rtap->pad;
767 	}
768 
769 	/*
770 	 * First, we may need to make a copy of the skb because
771 	 *  (1) we need to modify it for radiotap (if not present), and
772 	 *  (2) the other RX handlers will modify the skb we got.
773 	 *
774 	 * We don't need to, of course, if we aren't going to return
775 	 * the SKB because it has a bad FCS/PLCP checksum.
776 	 */
777 
778 	if (ieee80211_hw_check(&local->hw, RX_INCLUDES_FCS)) {
779 		if (unlikely(origskb->len <= FCS_LEN)) {
780 			/* driver bug */
781 			WARN_ON(1);
782 			dev_kfree_skb(origskb);
783 			return NULL;
784 		}
785 		present_fcs_len = FCS_LEN;
786 	}
787 
788 	/* ensure hdr->frame_control and vendor radiotap data are in skb head */
789 	if (!pskb_may_pull(origskb, 2 + rtap_space)) {
790 		dev_kfree_skb(origskb);
791 		return NULL;
792 	}
793 
794 	only_monitor = should_drop_frame(origskb, present_fcs_len, rtap_space);
795 
796 	if (!local->monitors || (status->flag & RX_FLAG_SKIP_MONITOR)) {
797 		if (only_monitor) {
798 			dev_kfree_skb(origskb);
799 			return NULL;
800 		}
801 
802 		remove_monitor_info(origskb, present_fcs_len, rtap_space);
803 		return origskb;
804 	}
805 
806 	ieee80211_handle_mu_mimo_mon(monitor_sdata, origskb, rtap_space);
807 
808 	list_for_each_entry_rcu(sdata, &local->mon_list, u.mntr.list) {
809 		bool last_monitor = list_is_last(&sdata->u.mntr.list,
810 						 &local->mon_list);
811 
812 		if (!monskb)
813 			monskb = ieee80211_make_monitor_skb(local, &origskb,
814 							    rate, rtap_space,
815 							    only_monitor &&
816 							    last_monitor);
817 
818 		if (monskb) {
819 			struct sk_buff *skb;
820 
821 			if (last_monitor) {
822 				skb = monskb;
823 				monskb = NULL;
824 			} else {
825 				skb = skb_clone(monskb, GFP_ATOMIC);
826 			}
827 
828 			if (skb) {
829 				skb->dev = sdata->dev;
830 				ieee80211_rx_stats(skb->dev, skb->len);
831 				netif_receive_skb(skb);
832 			}
833 		}
834 
835 		if (last_monitor)
836 			break;
837 	}
838 
839 	/* this happens if last_monitor was erroneously false */
840 	dev_kfree_skb(monskb);
841 
842 	/* ditto */
843 	if (!origskb)
844 		return NULL;
845 
846 	remove_monitor_info(origskb, present_fcs_len, rtap_space);
847 	return origskb;
848 }
849 
850 static void ieee80211_parse_qos(struct ieee80211_rx_data *rx)
851 {
852 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
853 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
854 	int tid, seqno_idx, security_idx;
855 
856 	/* does the frame have a qos control field? */
857 	if (ieee80211_is_data_qos(hdr->frame_control)) {
858 		u8 *qc = ieee80211_get_qos_ctl(hdr);
859 		/* frame has qos control */
860 		tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
861 		if (*qc & IEEE80211_QOS_CTL_A_MSDU_PRESENT)
862 			status->rx_flags |= IEEE80211_RX_AMSDU;
863 
864 		seqno_idx = tid;
865 		security_idx = tid;
866 	} else {
867 		/*
868 		 * IEEE 802.11-2007, 7.1.3.4.1 ("Sequence Number field"):
869 		 *
870 		 *	Sequence numbers for management frames, QoS data
871 		 *	frames with a broadcast/multicast address in the
872 		 *	Address 1 field, and all non-QoS data frames sent
873 		 *	by QoS STAs are assigned using an additional single
874 		 *	modulo-4096 counter, [...]
875 		 *
876 		 * We also use that counter for non-QoS STAs.
877 		 */
878 		seqno_idx = IEEE80211_NUM_TIDS;
879 		security_idx = 0;
880 		if (ieee80211_is_mgmt(hdr->frame_control))
881 			security_idx = IEEE80211_NUM_TIDS;
882 		tid = 0;
883 	}
884 
885 	rx->seqno_idx = seqno_idx;
886 	rx->security_idx = security_idx;
887 	/* Set skb->priority to 1d tag if highest order bit of TID is not set.
888 	 * For now, set skb->priority to 0 for other cases. */
889 	rx->skb->priority = (tid > 7) ? 0 : tid;
890 }
891 
892 /**
893  * DOC: Packet alignment
894  *
895  * Drivers always need to pass packets that are aligned to two-byte boundaries
896  * to the stack.
897  *
898  * Additionally, should, if possible, align the payload data in a way that
899  * guarantees that the contained IP header is aligned to a four-byte
900  * boundary. In the case of regular frames, this simply means aligning the
901  * payload to a four-byte boundary (because either the IP header is directly
902  * contained, or IV/RFC1042 headers that have a length divisible by four are
903  * in front of it).  If the payload data is not properly aligned and the
904  * architecture doesn't support efficient unaligned operations, mac80211
905  * will align the data.
906  *
907  * With A-MSDU frames, however, the payload data address must yield two modulo
908  * four because there are 14-byte 802.3 headers within the A-MSDU frames that
909  * push the IP header further back to a multiple of four again. Thankfully, the
910  * specs were sane enough this time around to require padding each A-MSDU
911  * subframe to a length that is a multiple of four.
912  *
913  * Padding like Atheros hardware adds which is between the 802.11 header and
914  * the payload is not supported, the driver is required to move the 802.11
915  * header to be directly in front of the payload in that case.
916  */
917 static void ieee80211_verify_alignment(struct ieee80211_rx_data *rx)
918 {
919 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
920 	WARN_ON_ONCE((unsigned long)rx->skb->data & 1);
921 #endif
922 }
923 
924 
925 /* rx handlers */
926 
927 static int ieee80211_is_unicast_robust_mgmt_frame(struct sk_buff *skb)
928 {
929 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
930 
931 	if (is_multicast_ether_addr(hdr->addr1))
932 		return 0;
933 
934 	return ieee80211_is_robust_mgmt_frame(skb);
935 }
936 
937 
938 static int ieee80211_is_multicast_robust_mgmt_frame(struct sk_buff *skb)
939 {
940 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
941 
942 	if (!is_multicast_ether_addr(hdr->addr1))
943 		return 0;
944 
945 	return ieee80211_is_robust_mgmt_frame(skb);
946 }
947 
948 
949 /* Get the BIP key index from MMIE; return -1 if this is not a BIP frame */
950 static int ieee80211_get_mmie_keyidx(struct sk_buff *skb)
951 {
952 	struct ieee80211_mgmt *hdr = (struct ieee80211_mgmt *) skb->data;
953 	struct ieee80211_mmie *mmie;
954 	struct ieee80211_mmie_16 *mmie16;
955 
956 	if (skb->len < 24 + sizeof(*mmie) || !is_multicast_ether_addr(hdr->da))
957 		return -1;
958 
959 	if (!ieee80211_is_robust_mgmt_frame(skb))
960 		return -1; /* not a robust management frame */
961 
962 	mmie = (struct ieee80211_mmie *)
963 		(skb->data + skb->len - sizeof(*mmie));
964 	if (mmie->element_id == WLAN_EID_MMIE &&
965 	    mmie->length == sizeof(*mmie) - 2)
966 		return le16_to_cpu(mmie->key_id);
967 
968 	mmie16 = (struct ieee80211_mmie_16 *)
969 		(skb->data + skb->len - sizeof(*mmie16));
970 	if (skb->len >= 24 + sizeof(*mmie16) &&
971 	    mmie16->element_id == WLAN_EID_MMIE &&
972 	    mmie16->length == sizeof(*mmie16) - 2)
973 		return le16_to_cpu(mmie16->key_id);
974 
975 	return -1;
976 }
977 
978 static int ieee80211_get_cs_keyid(const struct ieee80211_cipher_scheme *cs,
979 				  struct sk_buff *skb)
980 {
981 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
982 	__le16 fc;
983 	int hdrlen;
984 	u8 keyid;
985 
986 	fc = hdr->frame_control;
987 	hdrlen = ieee80211_hdrlen(fc);
988 
989 	if (skb->len < hdrlen + cs->hdr_len)
990 		return -EINVAL;
991 
992 	skb_copy_bits(skb, hdrlen + cs->key_idx_off, &keyid, 1);
993 	keyid &= cs->key_idx_mask;
994 	keyid >>= cs->key_idx_shift;
995 
996 	return keyid;
997 }
998 
999 static ieee80211_rx_result ieee80211_rx_mesh_check(struct ieee80211_rx_data *rx)
1000 {
1001 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1002 	char *dev_addr = rx->sdata->vif.addr;
1003 
1004 	if (ieee80211_is_data(hdr->frame_control)) {
1005 		if (is_multicast_ether_addr(hdr->addr1)) {
1006 			if (ieee80211_has_tods(hdr->frame_control) ||
1007 			    !ieee80211_has_fromds(hdr->frame_control))
1008 				return RX_DROP_MONITOR;
1009 			if (ether_addr_equal(hdr->addr3, dev_addr))
1010 				return RX_DROP_MONITOR;
1011 		} else {
1012 			if (!ieee80211_has_a4(hdr->frame_control))
1013 				return RX_DROP_MONITOR;
1014 			if (ether_addr_equal(hdr->addr4, dev_addr))
1015 				return RX_DROP_MONITOR;
1016 		}
1017 	}
1018 
1019 	/* If there is not an established peer link and this is not a peer link
1020 	 * establisment frame, beacon or probe, drop the frame.
1021 	 */
1022 
1023 	if (!rx->sta || sta_plink_state(rx->sta) != NL80211_PLINK_ESTAB) {
1024 		struct ieee80211_mgmt *mgmt;
1025 
1026 		if (!ieee80211_is_mgmt(hdr->frame_control))
1027 			return RX_DROP_MONITOR;
1028 
1029 		if (ieee80211_is_action(hdr->frame_control)) {
1030 			u8 category;
1031 
1032 			/* make sure category field is present */
1033 			if (rx->skb->len < IEEE80211_MIN_ACTION_SIZE)
1034 				return RX_DROP_MONITOR;
1035 
1036 			mgmt = (struct ieee80211_mgmt *)hdr;
1037 			category = mgmt->u.action.category;
1038 			if (category != WLAN_CATEGORY_MESH_ACTION &&
1039 			    category != WLAN_CATEGORY_SELF_PROTECTED)
1040 				return RX_DROP_MONITOR;
1041 			return RX_CONTINUE;
1042 		}
1043 
1044 		if (ieee80211_is_probe_req(hdr->frame_control) ||
1045 		    ieee80211_is_probe_resp(hdr->frame_control) ||
1046 		    ieee80211_is_beacon(hdr->frame_control) ||
1047 		    ieee80211_is_auth(hdr->frame_control))
1048 			return RX_CONTINUE;
1049 
1050 		return RX_DROP_MONITOR;
1051 	}
1052 
1053 	return RX_CONTINUE;
1054 }
1055 
1056 static inline bool ieee80211_rx_reorder_ready(struct tid_ampdu_rx *tid_agg_rx,
1057 					      int index)
1058 {
1059 	struct sk_buff_head *frames = &tid_agg_rx->reorder_buf[index];
1060 	struct sk_buff *tail = skb_peek_tail(frames);
1061 	struct ieee80211_rx_status *status;
1062 
1063 	if (tid_agg_rx->reorder_buf_filtered & BIT_ULL(index))
1064 		return true;
1065 
1066 	if (!tail)
1067 		return false;
1068 
1069 	status = IEEE80211_SKB_RXCB(tail);
1070 	if (status->flag & RX_FLAG_AMSDU_MORE)
1071 		return false;
1072 
1073 	return true;
1074 }
1075 
1076 static void ieee80211_release_reorder_frame(struct ieee80211_sub_if_data *sdata,
1077 					    struct tid_ampdu_rx *tid_agg_rx,
1078 					    int index,
1079 					    struct sk_buff_head *frames)
1080 {
1081 	struct sk_buff_head *skb_list = &tid_agg_rx->reorder_buf[index];
1082 	struct sk_buff *skb;
1083 	struct ieee80211_rx_status *status;
1084 
1085 	lockdep_assert_held(&tid_agg_rx->reorder_lock);
1086 
1087 	if (skb_queue_empty(skb_list))
1088 		goto no_frame;
1089 
1090 	if (!ieee80211_rx_reorder_ready(tid_agg_rx, index)) {
1091 		__skb_queue_purge(skb_list);
1092 		goto no_frame;
1093 	}
1094 
1095 	/* release frames from the reorder ring buffer */
1096 	tid_agg_rx->stored_mpdu_num--;
1097 	while ((skb = __skb_dequeue(skb_list))) {
1098 		status = IEEE80211_SKB_RXCB(skb);
1099 		status->rx_flags |= IEEE80211_RX_DEFERRED_RELEASE;
1100 		__skb_queue_tail(frames, skb);
1101 	}
1102 
1103 no_frame:
1104 	tid_agg_rx->reorder_buf_filtered &= ~BIT_ULL(index);
1105 	tid_agg_rx->head_seq_num = ieee80211_sn_inc(tid_agg_rx->head_seq_num);
1106 }
1107 
1108 static void ieee80211_release_reorder_frames(struct ieee80211_sub_if_data *sdata,
1109 					     struct tid_ampdu_rx *tid_agg_rx,
1110 					     u16 head_seq_num,
1111 					     struct sk_buff_head *frames)
1112 {
1113 	int index;
1114 
1115 	lockdep_assert_held(&tid_agg_rx->reorder_lock);
1116 
1117 	while (ieee80211_sn_less(tid_agg_rx->head_seq_num, head_seq_num)) {
1118 		index = tid_agg_rx->head_seq_num % tid_agg_rx->buf_size;
1119 		ieee80211_release_reorder_frame(sdata, tid_agg_rx, index,
1120 						frames);
1121 	}
1122 }
1123 
1124 /*
1125  * Timeout (in jiffies) for skb's that are waiting in the RX reorder buffer. If
1126  * the skb was added to the buffer longer than this time ago, the earlier
1127  * frames that have not yet been received are assumed to be lost and the skb
1128  * can be released for processing. This may also release other skb's from the
1129  * reorder buffer if there are no additional gaps between the frames.
1130  *
1131  * Callers must hold tid_agg_rx->reorder_lock.
1132  */
1133 #define HT_RX_REORDER_BUF_TIMEOUT (HZ / 10)
1134 
1135 static void ieee80211_sta_reorder_release(struct ieee80211_sub_if_data *sdata,
1136 					  struct tid_ampdu_rx *tid_agg_rx,
1137 					  struct sk_buff_head *frames)
1138 {
1139 	int index, i, j;
1140 
1141 	lockdep_assert_held(&tid_agg_rx->reorder_lock);
1142 
1143 	/* release the buffer until next missing frame */
1144 	index = tid_agg_rx->head_seq_num % tid_agg_rx->buf_size;
1145 	if (!ieee80211_rx_reorder_ready(tid_agg_rx, index) &&
1146 	    tid_agg_rx->stored_mpdu_num) {
1147 		/*
1148 		 * No buffers ready to be released, but check whether any
1149 		 * frames in the reorder buffer have timed out.
1150 		 */
1151 		int skipped = 1;
1152 		for (j = (index + 1) % tid_agg_rx->buf_size; j != index;
1153 		     j = (j + 1) % tid_agg_rx->buf_size) {
1154 			if (!ieee80211_rx_reorder_ready(tid_agg_rx, j)) {
1155 				skipped++;
1156 				continue;
1157 			}
1158 			if (skipped &&
1159 			    !time_after(jiffies, tid_agg_rx->reorder_time[j] +
1160 					HT_RX_REORDER_BUF_TIMEOUT))
1161 				goto set_release_timer;
1162 
1163 			/* don't leave incomplete A-MSDUs around */
1164 			for (i = (index + 1) % tid_agg_rx->buf_size; i != j;
1165 			     i = (i + 1) % tid_agg_rx->buf_size)
1166 				__skb_queue_purge(&tid_agg_rx->reorder_buf[i]);
1167 
1168 			ht_dbg_ratelimited(sdata,
1169 					   "release an RX reorder frame due to timeout on earlier frames\n");
1170 			ieee80211_release_reorder_frame(sdata, tid_agg_rx, j,
1171 							frames);
1172 
1173 			/*
1174 			 * Increment the head seq# also for the skipped slots.
1175 			 */
1176 			tid_agg_rx->head_seq_num =
1177 				(tid_agg_rx->head_seq_num +
1178 				 skipped) & IEEE80211_SN_MASK;
1179 			skipped = 0;
1180 		}
1181 	} else while (ieee80211_rx_reorder_ready(tid_agg_rx, index)) {
1182 		ieee80211_release_reorder_frame(sdata, tid_agg_rx, index,
1183 						frames);
1184 		index =	tid_agg_rx->head_seq_num % tid_agg_rx->buf_size;
1185 	}
1186 
1187 	if (tid_agg_rx->stored_mpdu_num) {
1188 		j = index = tid_agg_rx->head_seq_num % tid_agg_rx->buf_size;
1189 
1190 		for (; j != (index - 1) % tid_agg_rx->buf_size;
1191 		     j = (j + 1) % tid_agg_rx->buf_size) {
1192 			if (ieee80211_rx_reorder_ready(tid_agg_rx, j))
1193 				break;
1194 		}
1195 
1196  set_release_timer:
1197 
1198 		if (!tid_agg_rx->removed)
1199 			mod_timer(&tid_agg_rx->reorder_timer,
1200 				  tid_agg_rx->reorder_time[j] + 1 +
1201 				  HT_RX_REORDER_BUF_TIMEOUT);
1202 	} else {
1203 		del_timer(&tid_agg_rx->reorder_timer);
1204 	}
1205 }
1206 
1207 /*
1208  * As this function belongs to the RX path it must be under
1209  * rcu_read_lock protection. It returns false if the frame
1210  * can be processed immediately, true if it was consumed.
1211  */
1212 static bool ieee80211_sta_manage_reorder_buf(struct ieee80211_sub_if_data *sdata,
1213 					     struct tid_ampdu_rx *tid_agg_rx,
1214 					     struct sk_buff *skb,
1215 					     struct sk_buff_head *frames)
1216 {
1217 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1218 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1219 	u16 sc = le16_to_cpu(hdr->seq_ctrl);
1220 	u16 mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4;
1221 	u16 head_seq_num, buf_size;
1222 	int index;
1223 	bool ret = true;
1224 
1225 	spin_lock(&tid_agg_rx->reorder_lock);
1226 
1227 	/*
1228 	 * Offloaded BA sessions have no known starting sequence number so pick
1229 	 * one from first Rxed frame for this tid after BA was started.
1230 	 */
1231 	if (unlikely(tid_agg_rx->auto_seq)) {
1232 		tid_agg_rx->auto_seq = false;
1233 		tid_agg_rx->ssn = mpdu_seq_num;
1234 		tid_agg_rx->head_seq_num = mpdu_seq_num;
1235 	}
1236 
1237 	buf_size = tid_agg_rx->buf_size;
1238 	head_seq_num = tid_agg_rx->head_seq_num;
1239 
1240 	/*
1241 	 * If the current MPDU's SN is smaller than the SSN, it shouldn't
1242 	 * be reordered.
1243 	 */
1244 	if (unlikely(!tid_agg_rx->started)) {
1245 		if (ieee80211_sn_less(mpdu_seq_num, head_seq_num)) {
1246 			ret = false;
1247 			goto out;
1248 		}
1249 		tid_agg_rx->started = true;
1250 	}
1251 
1252 	/* frame with out of date sequence number */
1253 	if (ieee80211_sn_less(mpdu_seq_num, head_seq_num)) {
1254 		dev_kfree_skb(skb);
1255 		goto out;
1256 	}
1257 
1258 	/*
1259 	 * If frame the sequence number exceeds our buffering window
1260 	 * size release some previous frames to make room for this one.
1261 	 */
1262 	if (!ieee80211_sn_less(mpdu_seq_num, head_seq_num + buf_size)) {
1263 		head_seq_num = ieee80211_sn_inc(
1264 				ieee80211_sn_sub(mpdu_seq_num, buf_size));
1265 		/* release stored frames up to new head to stack */
1266 		ieee80211_release_reorder_frames(sdata, tid_agg_rx,
1267 						 head_seq_num, frames);
1268 	}
1269 
1270 	/* Now the new frame is always in the range of the reordering buffer */
1271 
1272 	index = mpdu_seq_num % tid_agg_rx->buf_size;
1273 
1274 	/* check if we already stored this frame */
1275 	if (ieee80211_rx_reorder_ready(tid_agg_rx, index)) {
1276 		dev_kfree_skb(skb);
1277 		goto out;
1278 	}
1279 
1280 	/*
1281 	 * If the current MPDU is in the right order and nothing else
1282 	 * is stored we can process it directly, no need to buffer it.
1283 	 * If it is first but there's something stored, we may be able
1284 	 * to release frames after this one.
1285 	 */
1286 	if (mpdu_seq_num == tid_agg_rx->head_seq_num &&
1287 	    tid_agg_rx->stored_mpdu_num == 0) {
1288 		if (!(status->flag & RX_FLAG_AMSDU_MORE))
1289 			tid_agg_rx->head_seq_num =
1290 				ieee80211_sn_inc(tid_agg_rx->head_seq_num);
1291 		ret = false;
1292 		goto out;
1293 	}
1294 
1295 	/* put the frame in the reordering buffer */
1296 	__skb_queue_tail(&tid_agg_rx->reorder_buf[index], skb);
1297 	if (!(status->flag & RX_FLAG_AMSDU_MORE)) {
1298 		tid_agg_rx->reorder_time[index] = jiffies;
1299 		tid_agg_rx->stored_mpdu_num++;
1300 		ieee80211_sta_reorder_release(sdata, tid_agg_rx, frames);
1301 	}
1302 
1303  out:
1304 	spin_unlock(&tid_agg_rx->reorder_lock);
1305 	return ret;
1306 }
1307 
1308 /*
1309  * Reorder MPDUs from A-MPDUs, keeping them on a buffer. Returns
1310  * true if the MPDU was buffered, false if it should be processed.
1311  */
1312 static void ieee80211_rx_reorder_ampdu(struct ieee80211_rx_data *rx,
1313 				       struct sk_buff_head *frames)
1314 {
1315 	struct sk_buff *skb = rx->skb;
1316 	struct ieee80211_local *local = rx->local;
1317 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1318 	struct sta_info *sta = rx->sta;
1319 	struct tid_ampdu_rx *tid_agg_rx;
1320 	u16 sc;
1321 	u8 tid, ack_policy;
1322 
1323 	if (!ieee80211_is_data_qos(hdr->frame_control) ||
1324 	    is_multicast_ether_addr(hdr->addr1))
1325 		goto dont_reorder;
1326 
1327 	/*
1328 	 * filter the QoS data rx stream according to
1329 	 * STA/TID and check if this STA/TID is on aggregation
1330 	 */
1331 
1332 	if (!sta)
1333 		goto dont_reorder;
1334 
1335 	ack_policy = *ieee80211_get_qos_ctl(hdr) &
1336 		     IEEE80211_QOS_CTL_ACK_POLICY_MASK;
1337 	tid = ieee80211_get_tid(hdr);
1338 
1339 	tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
1340 	if (!tid_agg_rx) {
1341 		if (ack_policy == IEEE80211_QOS_CTL_ACK_POLICY_BLOCKACK &&
1342 		    !test_bit(tid, rx->sta->ampdu_mlme.agg_session_valid) &&
1343 		    !test_and_set_bit(tid, rx->sta->ampdu_mlme.unexpected_agg))
1344 			ieee80211_send_delba(rx->sdata, rx->sta->sta.addr, tid,
1345 					     WLAN_BACK_RECIPIENT,
1346 					     WLAN_REASON_QSTA_REQUIRE_SETUP);
1347 		goto dont_reorder;
1348 	}
1349 
1350 	/* qos null data frames are excluded */
1351 	if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC)))
1352 		goto dont_reorder;
1353 
1354 	/* not part of a BA session */
1355 	if (ack_policy != IEEE80211_QOS_CTL_ACK_POLICY_BLOCKACK &&
1356 	    ack_policy != IEEE80211_QOS_CTL_ACK_POLICY_NORMAL)
1357 		goto dont_reorder;
1358 
1359 	/* new, potentially un-ordered, ampdu frame - process it */
1360 
1361 	/* reset session timer */
1362 	if (tid_agg_rx->timeout)
1363 		tid_agg_rx->last_rx = jiffies;
1364 
1365 	/* if this mpdu is fragmented - terminate rx aggregation session */
1366 	sc = le16_to_cpu(hdr->seq_ctrl);
1367 	if (sc & IEEE80211_SCTL_FRAG) {
1368 		skb_queue_tail(&rx->sdata->skb_queue, skb);
1369 		ieee80211_queue_work(&local->hw, &rx->sdata->work);
1370 		return;
1371 	}
1372 
1373 	/*
1374 	 * No locking needed -- we will only ever process one
1375 	 * RX packet at a time, and thus own tid_agg_rx. All
1376 	 * other code manipulating it needs to (and does) make
1377 	 * sure that we cannot get to it any more before doing
1378 	 * anything with it.
1379 	 */
1380 	if (ieee80211_sta_manage_reorder_buf(rx->sdata, tid_agg_rx, skb,
1381 					     frames))
1382 		return;
1383 
1384  dont_reorder:
1385 	__skb_queue_tail(frames, skb);
1386 }
1387 
1388 static ieee80211_rx_result debug_noinline
1389 ieee80211_rx_h_check_dup(struct ieee80211_rx_data *rx)
1390 {
1391 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1392 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1393 
1394 	if (status->flag & RX_FLAG_DUP_VALIDATED)
1395 		return RX_CONTINUE;
1396 
1397 	/*
1398 	 * Drop duplicate 802.11 retransmissions
1399 	 * (IEEE 802.11-2012: 9.3.2.10 "Duplicate detection and recovery")
1400 	 */
1401 
1402 	if (rx->skb->len < 24)
1403 		return RX_CONTINUE;
1404 
1405 	if (ieee80211_is_ctl(hdr->frame_control) ||
1406 	    ieee80211_is_nullfunc(hdr->frame_control) ||
1407 	    ieee80211_is_qos_nullfunc(hdr->frame_control) ||
1408 	    is_multicast_ether_addr(hdr->addr1))
1409 		return RX_CONTINUE;
1410 
1411 	if (!rx->sta)
1412 		return RX_CONTINUE;
1413 
1414 	if (unlikely(ieee80211_has_retry(hdr->frame_control) &&
1415 		     rx->sta->last_seq_ctrl[rx->seqno_idx] == hdr->seq_ctrl)) {
1416 		I802_DEBUG_INC(rx->local->dot11FrameDuplicateCount);
1417 		rx->sta->rx_stats.num_duplicates++;
1418 		return RX_DROP_UNUSABLE;
1419 	} else if (!(status->flag & RX_FLAG_AMSDU_MORE)) {
1420 		rx->sta->last_seq_ctrl[rx->seqno_idx] = hdr->seq_ctrl;
1421 	}
1422 
1423 	return RX_CONTINUE;
1424 }
1425 
1426 static ieee80211_rx_result debug_noinline
1427 ieee80211_rx_h_check(struct ieee80211_rx_data *rx)
1428 {
1429 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1430 
1431 	/* Drop disallowed frame classes based on STA auth/assoc state;
1432 	 * IEEE 802.11, Chap 5.5.
1433 	 *
1434 	 * mac80211 filters only based on association state, i.e. it drops
1435 	 * Class 3 frames from not associated stations. hostapd sends
1436 	 * deauth/disassoc frames when needed. In addition, hostapd is
1437 	 * responsible for filtering on both auth and assoc states.
1438 	 */
1439 
1440 	if (ieee80211_vif_is_mesh(&rx->sdata->vif))
1441 		return ieee80211_rx_mesh_check(rx);
1442 
1443 	if (unlikely((ieee80211_is_data(hdr->frame_control) ||
1444 		      ieee80211_is_pspoll(hdr->frame_control)) &&
1445 		     rx->sdata->vif.type != NL80211_IFTYPE_ADHOC &&
1446 		     rx->sdata->vif.type != NL80211_IFTYPE_WDS &&
1447 		     rx->sdata->vif.type != NL80211_IFTYPE_OCB &&
1448 		     (!rx->sta || !test_sta_flag(rx->sta, WLAN_STA_ASSOC)))) {
1449 		/*
1450 		 * accept port control frames from the AP even when it's not
1451 		 * yet marked ASSOC to prevent a race where we don't set the
1452 		 * assoc bit quickly enough before it sends the first frame
1453 		 */
1454 		if (rx->sta && rx->sdata->vif.type == NL80211_IFTYPE_STATION &&
1455 		    ieee80211_is_data_present(hdr->frame_control)) {
1456 			unsigned int hdrlen;
1457 			__be16 ethertype;
1458 
1459 			hdrlen = ieee80211_hdrlen(hdr->frame_control);
1460 
1461 			if (rx->skb->len < hdrlen + 8)
1462 				return RX_DROP_MONITOR;
1463 
1464 			skb_copy_bits(rx->skb, hdrlen + 6, &ethertype, 2);
1465 			if (ethertype == rx->sdata->control_port_protocol)
1466 				return RX_CONTINUE;
1467 		}
1468 
1469 		if (rx->sdata->vif.type == NL80211_IFTYPE_AP &&
1470 		    cfg80211_rx_spurious_frame(rx->sdata->dev,
1471 					       hdr->addr2,
1472 					       GFP_ATOMIC))
1473 			return RX_DROP_UNUSABLE;
1474 
1475 		return RX_DROP_MONITOR;
1476 	}
1477 
1478 	return RX_CONTINUE;
1479 }
1480 
1481 
1482 static ieee80211_rx_result debug_noinline
1483 ieee80211_rx_h_check_more_data(struct ieee80211_rx_data *rx)
1484 {
1485 	struct ieee80211_local *local;
1486 	struct ieee80211_hdr *hdr;
1487 	struct sk_buff *skb;
1488 
1489 	local = rx->local;
1490 	skb = rx->skb;
1491 	hdr = (struct ieee80211_hdr *) skb->data;
1492 
1493 	if (!local->pspolling)
1494 		return RX_CONTINUE;
1495 
1496 	if (!ieee80211_has_fromds(hdr->frame_control))
1497 		/* this is not from AP */
1498 		return RX_CONTINUE;
1499 
1500 	if (!ieee80211_is_data(hdr->frame_control))
1501 		return RX_CONTINUE;
1502 
1503 	if (!ieee80211_has_moredata(hdr->frame_control)) {
1504 		/* AP has no more frames buffered for us */
1505 		local->pspolling = false;
1506 		return RX_CONTINUE;
1507 	}
1508 
1509 	/* more data bit is set, let's request a new frame from the AP */
1510 	ieee80211_send_pspoll(local, rx->sdata);
1511 
1512 	return RX_CONTINUE;
1513 }
1514 
1515 static void sta_ps_start(struct sta_info *sta)
1516 {
1517 	struct ieee80211_sub_if_data *sdata = sta->sdata;
1518 	struct ieee80211_local *local = sdata->local;
1519 	struct ps_data *ps;
1520 	int tid;
1521 
1522 	if (sta->sdata->vif.type == NL80211_IFTYPE_AP ||
1523 	    sta->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
1524 		ps = &sdata->bss->ps;
1525 	else
1526 		return;
1527 
1528 	atomic_inc(&ps->num_sta_ps);
1529 	set_sta_flag(sta, WLAN_STA_PS_STA);
1530 	if (!ieee80211_hw_check(&local->hw, AP_LINK_PS))
1531 		drv_sta_notify(local, sdata, STA_NOTIFY_SLEEP, &sta->sta);
1532 	ps_dbg(sdata, "STA %pM aid %d enters power save mode\n",
1533 	       sta->sta.addr, sta->sta.aid);
1534 
1535 	ieee80211_clear_fast_xmit(sta);
1536 
1537 	if (!sta->sta.txq[0])
1538 		return;
1539 
1540 	for (tid = 0; tid < IEEE80211_NUM_TIDS; tid++) {
1541 		if (txq_has_queue(sta->sta.txq[tid]))
1542 			set_bit(tid, &sta->txq_buffered_tids);
1543 		else
1544 			clear_bit(tid, &sta->txq_buffered_tids);
1545 	}
1546 }
1547 
1548 static void sta_ps_end(struct sta_info *sta)
1549 {
1550 	ps_dbg(sta->sdata, "STA %pM aid %d exits power save mode\n",
1551 	       sta->sta.addr, sta->sta.aid);
1552 
1553 	if (test_sta_flag(sta, WLAN_STA_PS_DRIVER)) {
1554 		/*
1555 		 * Clear the flag only if the other one is still set
1556 		 * so that the TX path won't start TX'ing new frames
1557 		 * directly ... In the case that the driver flag isn't
1558 		 * set ieee80211_sta_ps_deliver_wakeup() will clear it.
1559 		 */
1560 		clear_sta_flag(sta, WLAN_STA_PS_STA);
1561 		ps_dbg(sta->sdata, "STA %pM aid %d driver-ps-blocked\n",
1562 		       sta->sta.addr, sta->sta.aid);
1563 		return;
1564 	}
1565 
1566 	set_sta_flag(sta, WLAN_STA_PS_DELIVER);
1567 	clear_sta_flag(sta, WLAN_STA_PS_STA);
1568 	ieee80211_sta_ps_deliver_wakeup(sta);
1569 }
1570 
1571 int ieee80211_sta_ps_transition(struct ieee80211_sta *pubsta, bool start)
1572 {
1573 	struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
1574 	bool in_ps;
1575 
1576 	WARN_ON(!ieee80211_hw_check(&sta->local->hw, AP_LINK_PS));
1577 
1578 	/* Don't let the same PS state be set twice */
1579 	in_ps = test_sta_flag(sta, WLAN_STA_PS_STA);
1580 	if ((start && in_ps) || (!start && !in_ps))
1581 		return -EINVAL;
1582 
1583 	if (start)
1584 		sta_ps_start(sta);
1585 	else
1586 		sta_ps_end(sta);
1587 
1588 	return 0;
1589 }
1590 EXPORT_SYMBOL(ieee80211_sta_ps_transition);
1591 
1592 void ieee80211_sta_pspoll(struct ieee80211_sta *pubsta)
1593 {
1594 	struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
1595 
1596 	if (test_sta_flag(sta, WLAN_STA_SP))
1597 		return;
1598 
1599 	if (!test_sta_flag(sta, WLAN_STA_PS_DRIVER))
1600 		ieee80211_sta_ps_deliver_poll_response(sta);
1601 	else
1602 		set_sta_flag(sta, WLAN_STA_PSPOLL);
1603 }
1604 EXPORT_SYMBOL(ieee80211_sta_pspoll);
1605 
1606 void ieee80211_sta_uapsd_trigger(struct ieee80211_sta *pubsta, u8 tid)
1607 {
1608 	struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
1609 	int ac = ieee80211_ac_from_tid(tid);
1610 
1611 	/*
1612 	 * If this AC is not trigger-enabled do nothing unless the
1613 	 * driver is calling us after it already checked.
1614 	 *
1615 	 * NB: This could/should check a separate bitmap of trigger-
1616 	 * enabled queues, but for now we only implement uAPSD w/o
1617 	 * TSPEC changes to the ACs, so they're always the same.
1618 	 */
1619 	if (!(sta->sta.uapsd_queues & ieee80211_ac_to_qos_mask[ac]) &&
1620 	    tid != IEEE80211_NUM_TIDS)
1621 		return;
1622 
1623 	/* if we are in a service period, do nothing */
1624 	if (test_sta_flag(sta, WLAN_STA_SP))
1625 		return;
1626 
1627 	if (!test_sta_flag(sta, WLAN_STA_PS_DRIVER))
1628 		ieee80211_sta_ps_deliver_uapsd(sta);
1629 	else
1630 		set_sta_flag(sta, WLAN_STA_UAPSD);
1631 }
1632 EXPORT_SYMBOL(ieee80211_sta_uapsd_trigger);
1633 
1634 static ieee80211_rx_result debug_noinline
1635 ieee80211_rx_h_uapsd_and_pspoll(struct ieee80211_rx_data *rx)
1636 {
1637 	struct ieee80211_sub_if_data *sdata = rx->sdata;
1638 	struct ieee80211_hdr *hdr = (void *)rx->skb->data;
1639 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1640 
1641 	if (!rx->sta)
1642 		return RX_CONTINUE;
1643 
1644 	if (sdata->vif.type != NL80211_IFTYPE_AP &&
1645 	    sdata->vif.type != NL80211_IFTYPE_AP_VLAN)
1646 		return RX_CONTINUE;
1647 
1648 	/*
1649 	 * The device handles station powersave, so don't do anything about
1650 	 * uAPSD and PS-Poll frames (the latter shouldn't even come up from
1651 	 * it to mac80211 since they're handled.)
1652 	 */
1653 	if (ieee80211_hw_check(&sdata->local->hw, AP_LINK_PS))
1654 		return RX_CONTINUE;
1655 
1656 	/*
1657 	 * Don't do anything if the station isn't already asleep. In
1658 	 * the uAPSD case, the station will probably be marked asleep,
1659 	 * in the PS-Poll case the station must be confused ...
1660 	 */
1661 	if (!test_sta_flag(rx->sta, WLAN_STA_PS_STA))
1662 		return RX_CONTINUE;
1663 
1664 	if (unlikely(ieee80211_is_pspoll(hdr->frame_control))) {
1665 		ieee80211_sta_pspoll(&rx->sta->sta);
1666 
1667 		/* Free PS Poll skb here instead of returning RX_DROP that would
1668 		 * count as an dropped frame. */
1669 		dev_kfree_skb(rx->skb);
1670 
1671 		return RX_QUEUED;
1672 	} else if (!ieee80211_has_morefrags(hdr->frame_control) &&
1673 		   !(status->rx_flags & IEEE80211_RX_DEFERRED_RELEASE) &&
1674 		   ieee80211_has_pm(hdr->frame_control) &&
1675 		   (ieee80211_is_data_qos(hdr->frame_control) ||
1676 		    ieee80211_is_qos_nullfunc(hdr->frame_control))) {
1677 		u8 tid = ieee80211_get_tid(hdr);
1678 
1679 		ieee80211_sta_uapsd_trigger(&rx->sta->sta, tid);
1680 	}
1681 
1682 	return RX_CONTINUE;
1683 }
1684 
1685 static ieee80211_rx_result debug_noinline
1686 ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx)
1687 {
1688 	struct sta_info *sta = rx->sta;
1689 	struct sk_buff *skb = rx->skb;
1690 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1691 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1692 	int i;
1693 
1694 	if (!sta)
1695 		return RX_CONTINUE;
1696 
1697 	/*
1698 	 * Update last_rx only for IBSS packets which are for the current
1699 	 * BSSID and for station already AUTHORIZED to avoid keeping the
1700 	 * current IBSS network alive in cases where other STAs start
1701 	 * using different BSSID. This will also give the station another
1702 	 * chance to restart the authentication/authorization in case
1703 	 * something went wrong the first time.
1704 	 */
1705 	if (rx->sdata->vif.type == NL80211_IFTYPE_ADHOC) {
1706 		u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len,
1707 						NL80211_IFTYPE_ADHOC);
1708 		if (ether_addr_equal(bssid, rx->sdata->u.ibss.bssid) &&
1709 		    test_sta_flag(sta, WLAN_STA_AUTHORIZED)) {
1710 			sta->rx_stats.last_rx = jiffies;
1711 			if (ieee80211_is_data(hdr->frame_control) &&
1712 			    !is_multicast_ether_addr(hdr->addr1))
1713 				sta->rx_stats.last_rate =
1714 					sta_stats_encode_rate(status);
1715 		}
1716 	} else if (rx->sdata->vif.type == NL80211_IFTYPE_OCB) {
1717 		sta->rx_stats.last_rx = jiffies;
1718 	} else if (!is_multicast_ether_addr(hdr->addr1)) {
1719 		/*
1720 		 * Mesh beacons will update last_rx when if they are found to
1721 		 * match the current local configuration when processed.
1722 		 */
1723 		sta->rx_stats.last_rx = jiffies;
1724 		if (ieee80211_is_data(hdr->frame_control))
1725 			sta->rx_stats.last_rate = sta_stats_encode_rate(status);
1726 	}
1727 
1728 	if (rx->sdata->vif.type == NL80211_IFTYPE_STATION)
1729 		ieee80211_sta_rx_notify(rx->sdata, hdr);
1730 
1731 	sta->rx_stats.fragments++;
1732 
1733 	u64_stats_update_begin(&rx->sta->rx_stats.syncp);
1734 	sta->rx_stats.bytes += rx->skb->len;
1735 	u64_stats_update_end(&rx->sta->rx_stats.syncp);
1736 
1737 	if (!(status->flag & RX_FLAG_NO_SIGNAL_VAL)) {
1738 		sta->rx_stats.last_signal = status->signal;
1739 		ewma_signal_add(&sta->rx_stats_avg.signal, -status->signal);
1740 	}
1741 
1742 	if (status->chains) {
1743 		sta->rx_stats.chains = status->chains;
1744 		for (i = 0; i < ARRAY_SIZE(status->chain_signal); i++) {
1745 			int signal = status->chain_signal[i];
1746 
1747 			if (!(status->chains & BIT(i)))
1748 				continue;
1749 
1750 			sta->rx_stats.chain_signal_last[i] = signal;
1751 			ewma_signal_add(&sta->rx_stats_avg.chain_signal[i],
1752 					-signal);
1753 		}
1754 	}
1755 
1756 	/*
1757 	 * Change STA power saving mode only at the end of a frame
1758 	 * exchange sequence, and only for a data or management
1759 	 * frame as specified in IEEE 802.11-2016 11.2.3.2
1760 	 */
1761 	if (!ieee80211_hw_check(&sta->local->hw, AP_LINK_PS) &&
1762 	    !ieee80211_has_morefrags(hdr->frame_control) &&
1763 	    !is_multicast_ether_addr(hdr->addr1) &&
1764 	    (ieee80211_is_mgmt(hdr->frame_control) ||
1765 	     ieee80211_is_data(hdr->frame_control)) &&
1766 	    !(status->rx_flags & IEEE80211_RX_DEFERRED_RELEASE) &&
1767 	    (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1768 	     rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)) {
1769 		if (test_sta_flag(sta, WLAN_STA_PS_STA)) {
1770 			if (!ieee80211_has_pm(hdr->frame_control))
1771 				sta_ps_end(sta);
1772 		} else {
1773 			if (ieee80211_has_pm(hdr->frame_control))
1774 				sta_ps_start(sta);
1775 		}
1776 	}
1777 
1778 	/* mesh power save support */
1779 	if (ieee80211_vif_is_mesh(&rx->sdata->vif))
1780 		ieee80211_mps_rx_h_sta_process(sta, hdr);
1781 
1782 	/*
1783 	 * Drop (qos-)data::nullfunc frames silently, since they
1784 	 * are used only to control station power saving mode.
1785 	 */
1786 	if (ieee80211_is_nullfunc(hdr->frame_control) ||
1787 	    ieee80211_is_qos_nullfunc(hdr->frame_control)) {
1788 		I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
1789 
1790 		/*
1791 		 * If we receive a 4-addr nullfunc frame from a STA
1792 		 * that was not moved to a 4-addr STA vlan yet send
1793 		 * the event to userspace and for older hostapd drop
1794 		 * the frame to the monitor interface.
1795 		 */
1796 		if (ieee80211_has_a4(hdr->frame_control) &&
1797 		    (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1798 		     (rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1799 		      !rx->sdata->u.vlan.sta))) {
1800 			if (!test_and_set_sta_flag(sta, WLAN_STA_4ADDR_EVENT))
1801 				cfg80211_rx_unexpected_4addr_frame(
1802 					rx->sdata->dev, sta->sta.addr,
1803 					GFP_ATOMIC);
1804 			return RX_DROP_MONITOR;
1805 		}
1806 		/*
1807 		 * Update counter and free packet here to avoid
1808 		 * counting this as a dropped packed.
1809 		 */
1810 		sta->rx_stats.packets++;
1811 		dev_kfree_skb(rx->skb);
1812 		return RX_QUEUED;
1813 	}
1814 
1815 	return RX_CONTINUE;
1816 } /* ieee80211_rx_h_sta_process */
1817 
1818 static ieee80211_rx_result debug_noinline
1819 ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
1820 {
1821 	struct sk_buff *skb = rx->skb;
1822 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1823 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1824 	int keyidx;
1825 	int hdrlen;
1826 	ieee80211_rx_result result = RX_DROP_UNUSABLE;
1827 	struct ieee80211_key *sta_ptk = NULL;
1828 	int mmie_keyidx = -1;
1829 	__le16 fc;
1830 	const struct ieee80211_cipher_scheme *cs = NULL;
1831 
1832 	/*
1833 	 * Key selection 101
1834 	 *
1835 	 * There are four types of keys:
1836 	 *  - GTK (group keys)
1837 	 *  - IGTK (group keys for management frames)
1838 	 *  - PTK (pairwise keys)
1839 	 *  - STK (station-to-station pairwise keys)
1840 	 *
1841 	 * When selecting a key, we have to distinguish between multicast
1842 	 * (including broadcast) and unicast frames, the latter can only
1843 	 * use PTKs and STKs while the former always use GTKs and IGTKs.
1844 	 * Unless, of course, actual WEP keys ("pre-RSNA") are used, then
1845 	 * unicast frames can also use key indices like GTKs. Hence, if we
1846 	 * don't have a PTK/STK we check the key index for a WEP key.
1847 	 *
1848 	 * Note that in a regular BSS, multicast frames are sent by the
1849 	 * AP only, associated stations unicast the frame to the AP first
1850 	 * which then multicasts it on their behalf.
1851 	 *
1852 	 * There is also a slight problem in IBSS mode: GTKs are negotiated
1853 	 * with each station, that is something we don't currently handle.
1854 	 * The spec seems to expect that one negotiates the same key with
1855 	 * every station but there's no such requirement; VLANs could be
1856 	 * possible.
1857 	 */
1858 
1859 	/* start without a key */
1860 	rx->key = NULL;
1861 	fc = hdr->frame_control;
1862 
1863 	if (rx->sta) {
1864 		int keyid = rx->sta->ptk_idx;
1865 
1866 		if (ieee80211_has_protected(fc) && rx->sta->cipher_scheme) {
1867 			cs = rx->sta->cipher_scheme;
1868 			keyid = ieee80211_get_cs_keyid(cs, rx->skb);
1869 			if (unlikely(keyid < 0))
1870 				return RX_DROP_UNUSABLE;
1871 		}
1872 		sta_ptk = rcu_dereference(rx->sta->ptk[keyid]);
1873 	}
1874 
1875 	if (!ieee80211_has_protected(fc))
1876 		mmie_keyidx = ieee80211_get_mmie_keyidx(rx->skb);
1877 
1878 	if (!is_multicast_ether_addr(hdr->addr1) && sta_ptk) {
1879 		rx->key = sta_ptk;
1880 		if ((status->flag & RX_FLAG_DECRYPTED) &&
1881 		    (status->flag & RX_FLAG_IV_STRIPPED))
1882 			return RX_CONTINUE;
1883 		/* Skip decryption if the frame is not protected. */
1884 		if (!ieee80211_has_protected(fc))
1885 			return RX_CONTINUE;
1886 	} else if (mmie_keyidx >= 0) {
1887 		/* Broadcast/multicast robust management frame / BIP */
1888 		if ((status->flag & RX_FLAG_DECRYPTED) &&
1889 		    (status->flag & RX_FLAG_IV_STRIPPED))
1890 			return RX_CONTINUE;
1891 
1892 		if (mmie_keyidx < NUM_DEFAULT_KEYS ||
1893 		    mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
1894 			return RX_DROP_MONITOR; /* unexpected BIP keyidx */
1895 		if (rx->sta) {
1896 			if (ieee80211_is_group_privacy_action(skb) &&
1897 			    test_sta_flag(rx->sta, WLAN_STA_MFP))
1898 				return RX_DROP_MONITOR;
1899 
1900 			rx->key = rcu_dereference(rx->sta->gtk[mmie_keyidx]);
1901 		}
1902 		if (!rx->key)
1903 			rx->key = rcu_dereference(rx->sdata->keys[mmie_keyidx]);
1904 	} else if (!ieee80211_has_protected(fc)) {
1905 		/*
1906 		 * The frame was not protected, so skip decryption. However, we
1907 		 * need to set rx->key if there is a key that could have been
1908 		 * used so that the frame may be dropped if encryption would
1909 		 * have been expected.
1910 		 */
1911 		struct ieee80211_key *key = NULL;
1912 		struct ieee80211_sub_if_data *sdata = rx->sdata;
1913 		int i;
1914 
1915 		if (ieee80211_is_mgmt(fc) &&
1916 		    is_multicast_ether_addr(hdr->addr1) &&
1917 		    (key = rcu_dereference(rx->sdata->default_mgmt_key)))
1918 			rx->key = key;
1919 		else {
1920 			if (rx->sta) {
1921 				for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
1922 					key = rcu_dereference(rx->sta->gtk[i]);
1923 					if (key)
1924 						break;
1925 				}
1926 			}
1927 			if (!key) {
1928 				for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
1929 					key = rcu_dereference(sdata->keys[i]);
1930 					if (key)
1931 						break;
1932 				}
1933 			}
1934 			if (key)
1935 				rx->key = key;
1936 		}
1937 		return RX_CONTINUE;
1938 	} else {
1939 		u8 keyid;
1940 
1941 		/*
1942 		 * The device doesn't give us the IV so we won't be
1943 		 * able to look up the key. That's ok though, we
1944 		 * don't need to decrypt the frame, we just won't
1945 		 * be able to keep statistics accurate.
1946 		 * Except for key threshold notifications, should
1947 		 * we somehow allow the driver to tell us which key
1948 		 * the hardware used if this flag is set?
1949 		 */
1950 		if ((status->flag & RX_FLAG_DECRYPTED) &&
1951 		    (status->flag & RX_FLAG_IV_STRIPPED))
1952 			return RX_CONTINUE;
1953 
1954 		hdrlen = ieee80211_hdrlen(fc);
1955 
1956 		if (cs) {
1957 			keyidx = ieee80211_get_cs_keyid(cs, rx->skb);
1958 
1959 			if (unlikely(keyidx < 0))
1960 				return RX_DROP_UNUSABLE;
1961 		} else {
1962 			if (rx->skb->len < 8 + hdrlen)
1963 				return RX_DROP_UNUSABLE; /* TODO: count this? */
1964 			/*
1965 			 * no need to call ieee80211_wep_get_keyidx,
1966 			 * it verifies a bunch of things we've done already
1967 			 */
1968 			skb_copy_bits(rx->skb, hdrlen + 3, &keyid, 1);
1969 			keyidx = keyid >> 6;
1970 		}
1971 
1972 		/* check per-station GTK first, if multicast packet */
1973 		if (is_multicast_ether_addr(hdr->addr1) && rx->sta)
1974 			rx->key = rcu_dereference(rx->sta->gtk[keyidx]);
1975 
1976 		/* if not found, try default key */
1977 		if (!rx->key) {
1978 			rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
1979 
1980 			/*
1981 			 * RSNA-protected unicast frames should always be
1982 			 * sent with pairwise or station-to-station keys,
1983 			 * but for WEP we allow using a key index as well.
1984 			 */
1985 			if (rx->key &&
1986 			    rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP40 &&
1987 			    rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP104 &&
1988 			    !is_multicast_ether_addr(hdr->addr1))
1989 				rx->key = NULL;
1990 		}
1991 	}
1992 
1993 	if (rx->key) {
1994 		if (unlikely(rx->key->flags & KEY_FLAG_TAINTED))
1995 			return RX_DROP_MONITOR;
1996 
1997 		/* TODO: add threshold stuff again */
1998 	} else {
1999 		return RX_DROP_MONITOR;
2000 	}
2001 
2002 	switch (rx->key->conf.cipher) {
2003 	case WLAN_CIPHER_SUITE_WEP40:
2004 	case WLAN_CIPHER_SUITE_WEP104:
2005 		result = ieee80211_crypto_wep_decrypt(rx);
2006 		break;
2007 	case WLAN_CIPHER_SUITE_TKIP:
2008 		result = ieee80211_crypto_tkip_decrypt(rx);
2009 		break;
2010 	case WLAN_CIPHER_SUITE_CCMP:
2011 		result = ieee80211_crypto_ccmp_decrypt(
2012 			rx, IEEE80211_CCMP_MIC_LEN);
2013 		break;
2014 	case WLAN_CIPHER_SUITE_CCMP_256:
2015 		result = ieee80211_crypto_ccmp_decrypt(
2016 			rx, IEEE80211_CCMP_256_MIC_LEN);
2017 		break;
2018 	case WLAN_CIPHER_SUITE_AES_CMAC:
2019 		result = ieee80211_crypto_aes_cmac_decrypt(rx);
2020 		break;
2021 	case WLAN_CIPHER_SUITE_BIP_CMAC_256:
2022 		result = ieee80211_crypto_aes_cmac_256_decrypt(rx);
2023 		break;
2024 	case WLAN_CIPHER_SUITE_BIP_GMAC_128:
2025 	case WLAN_CIPHER_SUITE_BIP_GMAC_256:
2026 		result = ieee80211_crypto_aes_gmac_decrypt(rx);
2027 		break;
2028 	case WLAN_CIPHER_SUITE_GCMP:
2029 	case WLAN_CIPHER_SUITE_GCMP_256:
2030 		result = ieee80211_crypto_gcmp_decrypt(rx);
2031 		break;
2032 	default:
2033 		result = ieee80211_crypto_hw_decrypt(rx);
2034 	}
2035 
2036 	/* the hdr variable is invalid after the decrypt handlers */
2037 
2038 	/* either the frame has been decrypted or will be dropped */
2039 	status->flag |= RX_FLAG_DECRYPTED;
2040 
2041 	return result;
2042 }
2043 
2044 static inline struct ieee80211_fragment_entry *
2045 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
2046 			 unsigned int frag, unsigned int seq, int rx_queue,
2047 			 struct sk_buff **skb)
2048 {
2049 	struct ieee80211_fragment_entry *entry;
2050 
2051 	entry = &sdata->fragments[sdata->fragment_next++];
2052 	if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
2053 		sdata->fragment_next = 0;
2054 
2055 	if (!skb_queue_empty(&entry->skb_list))
2056 		__skb_queue_purge(&entry->skb_list);
2057 
2058 	__skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
2059 	*skb = NULL;
2060 	entry->first_frag_time = jiffies;
2061 	entry->seq = seq;
2062 	entry->rx_queue = rx_queue;
2063 	entry->last_frag = frag;
2064 	entry->check_sequential_pn = false;
2065 	entry->extra_len = 0;
2066 
2067 	return entry;
2068 }
2069 
2070 static inline struct ieee80211_fragment_entry *
2071 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
2072 			  unsigned int frag, unsigned int seq,
2073 			  int rx_queue, struct ieee80211_hdr *hdr)
2074 {
2075 	struct ieee80211_fragment_entry *entry;
2076 	int i, idx;
2077 
2078 	idx = sdata->fragment_next;
2079 	for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
2080 		struct ieee80211_hdr *f_hdr;
2081 		struct sk_buff *f_skb;
2082 
2083 		idx--;
2084 		if (idx < 0)
2085 			idx = IEEE80211_FRAGMENT_MAX - 1;
2086 
2087 		entry = &sdata->fragments[idx];
2088 		if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
2089 		    entry->rx_queue != rx_queue ||
2090 		    entry->last_frag + 1 != frag)
2091 			continue;
2092 
2093 		f_skb = __skb_peek(&entry->skb_list);
2094 		f_hdr = (struct ieee80211_hdr *) f_skb->data;
2095 
2096 		/*
2097 		 * Check ftype and addresses are equal, else check next fragment
2098 		 */
2099 		if (((hdr->frame_control ^ f_hdr->frame_control) &
2100 		     cpu_to_le16(IEEE80211_FCTL_FTYPE)) ||
2101 		    !ether_addr_equal(hdr->addr1, f_hdr->addr1) ||
2102 		    !ether_addr_equal(hdr->addr2, f_hdr->addr2))
2103 			continue;
2104 
2105 		if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) {
2106 			__skb_queue_purge(&entry->skb_list);
2107 			continue;
2108 		}
2109 		return entry;
2110 	}
2111 
2112 	return NULL;
2113 }
2114 
2115 static ieee80211_rx_result debug_noinline
2116 ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
2117 {
2118 	struct ieee80211_hdr *hdr;
2119 	u16 sc;
2120 	__le16 fc;
2121 	unsigned int frag, seq;
2122 	struct ieee80211_fragment_entry *entry;
2123 	struct sk_buff *skb;
2124 
2125 	hdr = (struct ieee80211_hdr *)rx->skb->data;
2126 	fc = hdr->frame_control;
2127 
2128 	if (ieee80211_is_ctl(fc))
2129 		return RX_CONTINUE;
2130 
2131 	sc = le16_to_cpu(hdr->seq_ctrl);
2132 	frag = sc & IEEE80211_SCTL_FRAG;
2133 
2134 	if (is_multicast_ether_addr(hdr->addr1)) {
2135 		I802_DEBUG_INC(rx->local->dot11MulticastReceivedFrameCount);
2136 		goto out_no_led;
2137 	}
2138 
2139 	if (likely(!ieee80211_has_morefrags(fc) && frag == 0))
2140 		goto out;
2141 
2142 	I802_DEBUG_INC(rx->local->rx_handlers_fragments);
2143 
2144 	if (skb_linearize(rx->skb))
2145 		return RX_DROP_UNUSABLE;
2146 
2147 	/*
2148 	 *  skb_linearize() might change the skb->data and
2149 	 *  previously cached variables (in this case, hdr) need to
2150 	 *  be refreshed with the new data.
2151 	 */
2152 	hdr = (struct ieee80211_hdr *)rx->skb->data;
2153 	seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
2154 
2155 	if (frag == 0) {
2156 		/* This is the first fragment of a new frame. */
2157 		entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
2158 						 rx->seqno_idx, &(rx->skb));
2159 		if (rx->key &&
2160 		    (rx->key->conf.cipher == WLAN_CIPHER_SUITE_CCMP ||
2161 		     rx->key->conf.cipher == WLAN_CIPHER_SUITE_CCMP_256 ||
2162 		     rx->key->conf.cipher == WLAN_CIPHER_SUITE_GCMP ||
2163 		     rx->key->conf.cipher == WLAN_CIPHER_SUITE_GCMP_256) &&
2164 		    ieee80211_has_protected(fc)) {
2165 			int queue = rx->security_idx;
2166 
2167 			/* Store CCMP/GCMP PN so that we can verify that the
2168 			 * next fragment has a sequential PN value.
2169 			 */
2170 			entry->check_sequential_pn = true;
2171 			memcpy(entry->last_pn,
2172 			       rx->key->u.ccmp.rx_pn[queue],
2173 			       IEEE80211_CCMP_PN_LEN);
2174 			BUILD_BUG_ON(offsetof(struct ieee80211_key,
2175 					      u.ccmp.rx_pn) !=
2176 				     offsetof(struct ieee80211_key,
2177 					      u.gcmp.rx_pn));
2178 			BUILD_BUG_ON(sizeof(rx->key->u.ccmp.rx_pn[queue]) !=
2179 				     sizeof(rx->key->u.gcmp.rx_pn[queue]));
2180 			BUILD_BUG_ON(IEEE80211_CCMP_PN_LEN !=
2181 				     IEEE80211_GCMP_PN_LEN);
2182 		}
2183 		return RX_QUEUED;
2184 	}
2185 
2186 	/* This is a fragment for a frame that should already be pending in
2187 	 * fragment cache. Add this fragment to the end of the pending entry.
2188 	 */
2189 	entry = ieee80211_reassemble_find(rx->sdata, frag, seq,
2190 					  rx->seqno_idx, hdr);
2191 	if (!entry) {
2192 		I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
2193 		return RX_DROP_MONITOR;
2194 	}
2195 
2196 	/* "The receiver shall discard MSDUs and MMPDUs whose constituent
2197 	 *  MPDU PN values are not incrementing in steps of 1."
2198 	 * see IEEE P802.11-REVmc/D5.0, 12.5.3.4.4, item d (for CCMP)
2199 	 * and IEEE P802.11-REVmc/D5.0, 12.5.5.4.4, item d (for GCMP)
2200 	 */
2201 	if (entry->check_sequential_pn) {
2202 		int i;
2203 		u8 pn[IEEE80211_CCMP_PN_LEN], *rpn;
2204 		int queue;
2205 
2206 		if (!rx->key ||
2207 		    (rx->key->conf.cipher != WLAN_CIPHER_SUITE_CCMP &&
2208 		     rx->key->conf.cipher != WLAN_CIPHER_SUITE_CCMP_256 &&
2209 		     rx->key->conf.cipher != WLAN_CIPHER_SUITE_GCMP &&
2210 		     rx->key->conf.cipher != WLAN_CIPHER_SUITE_GCMP_256))
2211 			return RX_DROP_UNUSABLE;
2212 		memcpy(pn, entry->last_pn, IEEE80211_CCMP_PN_LEN);
2213 		for (i = IEEE80211_CCMP_PN_LEN - 1; i >= 0; i--) {
2214 			pn[i]++;
2215 			if (pn[i])
2216 				break;
2217 		}
2218 		queue = rx->security_idx;
2219 		rpn = rx->key->u.ccmp.rx_pn[queue];
2220 		if (memcmp(pn, rpn, IEEE80211_CCMP_PN_LEN))
2221 			return RX_DROP_UNUSABLE;
2222 		memcpy(entry->last_pn, pn, IEEE80211_CCMP_PN_LEN);
2223 	}
2224 
2225 	skb_pull(rx->skb, ieee80211_hdrlen(fc));
2226 	__skb_queue_tail(&entry->skb_list, rx->skb);
2227 	entry->last_frag = frag;
2228 	entry->extra_len += rx->skb->len;
2229 	if (ieee80211_has_morefrags(fc)) {
2230 		rx->skb = NULL;
2231 		return RX_QUEUED;
2232 	}
2233 
2234 	rx->skb = __skb_dequeue(&entry->skb_list);
2235 	if (skb_tailroom(rx->skb) < entry->extra_len) {
2236 		I802_DEBUG_INC(rx->local->rx_expand_skb_head_defrag);
2237 		if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
2238 					      GFP_ATOMIC))) {
2239 			I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
2240 			__skb_queue_purge(&entry->skb_list);
2241 			return RX_DROP_UNUSABLE;
2242 		}
2243 	}
2244 	while ((skb = __skb_dequeue(&entry->skb_list))) {
2245 		skb_put_data(rx->skb, skb->data, skb->len);
2246 		dev_kfree_skb(skb);
2247 	}
2248 
2249  out:
2250 	ieee80211_led_rx(rx->local);
2251  out_no_led:
2252 	if (rx->sta)
2253 		rx->sta->rx_stats.packets++;
2254 	return RX_CONTINUE;
2255 }
2256 
2257 static int ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx)
2258 {
2259 	if (unlikely(!rx->sta || !test_sta_flag(rx->sta, WLAN_STA_AUTHORIZED)))
2260 		return -EACCES;
2261 
2262 	return 0;
2263 }
2264 
2265 static int ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx, __le16 fc)
2266 {
2267 	struct sk_buff *skb = rx->skb;
2268 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2269 
2270 	/*
2271 	 * Pass through unencrypted frames if the hardware has
2272 	 * decrypted them already.
2273 	 */
2274 	if (status->flag & RX_FLAG_DECRYPTED)
2275 		return 0;
2276 
2277 	/* Drop unencrypted frames if key is set. */
2278 	if (unlikely(!ieee80211_has_protected(fc) &&
2279 		     !ieee80211_is_nullfunc(fc) &&
2280 		     ieee80211_is_data(fc) && rx->key))
2281 		return -EACCES;
2282 
2283 	return 0;
2284 }
2285 
2286 static int ieee80211_drop_unencrypted_mgmt(struct ieee80211_rx_data *rx)
2287 {
2288 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
2289 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2290 	__le16 fc = hdr->frame_control;
2291 
2292 	/*
2293 	 * Pass through unencrypted frames if the hardware has
2294 	 * decrypted them already.
2295 	 */
2296 	if (status->flag & RX_FLAG_DECRYPTED)
2297 		return 0;
2298 
2299 	if (rx->sta && test_sta_flag(rx->sta, WLAN_STA_MFP)) {
2300 		if (unlikely(!ieee80211_has_protected(fc) &&
2301 			     ieee80211_is_unicast_robust_mgmt_frame(rx->skb) &&
2302 			     rx->key)) {
2303 			if (ieee80211_is_deauth(fc) ||
2304 			    ieee80211_is_disassoc(fc))
2305 				cfg80211_rx_unprot_mlme_mgmt(rx->sdata->dev,
2306 							     rx->skb->data,
2307 							     rx->skb->len);
2308 			return -EACCES;
2309 		}
2310 		/* BIP does not use Protected field, so need to check MMIE */
2311 		if (unlikely(ieee80211_is_multicast_robust_mgmt_frame(rx->skb) &&
2312 			     ieee80211_get_mmie_keyidx(rx->skb) < 0)) {
2313 			if (ieee80211_is_deauth(fc) ||
2314 			    ieee80211_is_disassoc(fc))
2315 				cfg80211_rx_unprot_mlme_mgmt(rx->sdata->dev,
2316 							     rx->skb->data,
2317 							     rx->skb->len);
2318 			return -EACCES;
2319 		}
2320 		/*
2321 		 * When using MFP, Action frames are not allowed prior to
2322 		 * having configured keys.
2323 		 */
2324 		if (unlikely(ieee80211_is_action(fc) && !rx->key &&
2325 			     ieee80211_is_robust_mgmt_frame(rx->skb)))
2326 			return -EACCES;
2327 	}
2328 
2329 	return 0;
2330 }
2331 
2332 static int
2333 __ieee80211_data_to_8023(struct ieee80211_rx_data *rx, bool *port_control)
2334 {
2335 	struct ieee80211_sub_if_data *sdata = rx->sdata;
2336 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
2337 	bool check_port_control = false;
2338 	struct ethhdr *ehdr;
2339 	int ret;
2340 
2341 	*port_control = false;
2342 	if (ieee80211_has_a4(hdr->frame_control) &&
2343 	    sdata->vif.type == NL80211_IFTYPE_AP_VLAN && !sdata->u.vlan.sta)
2344 		return -1;
2345 
2346 	if (sdata->vif.type == NL80211_IFTYPE_STATION &&
2347 	    !!sdata->u.mgd.use_4addr != !!ieee80211_has_a4(hdr->frame_control)) {
2348 
2349 		if (!sdata->u.mgd.use_4addr)
2350 			return -1;
2351 		else if (!ether_addr_equal(hdr->addr1, sdata->vif.addr))
2352 			check_port_control = true;
2353 	}
2354 
2355 	if (is_multicast_ether_addr(hdr->addr1) &&
2356 	    sdata->vif.type == NL80211_IFTYPE_AP_VLAN && sdata->u.vlan.sta)
2357 		return -1;
2358 
2359 	ret = ieee80211_data_to_8023(rx->skb, sdata->vif.addr, sdata->vif.type);
2360 	if (ret < 0)
2361 		return ret;
2362 
2363 	ehdr = (struct ethhdr *) rx->skb->data;
2364 	if (ehdr->h_proto == rx->sdata->control_port_protocol)
2365 		*port_control = true;
2366 	else if (check_port_control)
2367 		return -1;
2368 
2369 	return 0;
2370 }
2371 
2372 /*
2373  * requires that rx->skb is a frame with ethernet header
2374  */
2375 static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx, __le16 fc)
2376 {
2377 	static const u8 pae_group_addr[ETH_ALEN] __aligned(2)
2378 		= { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 };
2379 	struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
2380 
2381 	/*
2382 	 * Allow EAPOL frames to us/the PAE group address regardless
2383 	 * of whether the frame was encrypted or not.
2384 	 */
2385 	if (ehdr->h_proto == rx->sdata->control_port_protocol &&
2386 	    (ether_addr_equal(ehdr->h_dest, rx->sdata->vif.addr) ||
2387 	     ether_addr_equal(ehdr->h_dest, pae_group_addr)))
2388 		return true;
2389 
2390 	if (ieee80211_802_1x_port_control(rx) ||
2391 	    ieee80211_drop_unencrypted(rx, fc))
2392 		return false;
2393 
2394 	return true;
2395 }
2396 
2397 static void ieee80211_deliver_skb_to_local_stack(struct sk_buff *skb,
2398 						 struct ieee80211_rx_data *rx)
2399 {
2400 	struct ieee80211_sub_if_data *sdata = rx->sdata;
2401 	struct net_device *dev = sdata->dev;
2402 
2403 	if (unlikely((skb->protocol == sdata->control_port_protocol ||
2404 		      skb->protocol == cpu_to_be16(ETH_P_PREAUTH)) &&
2405 		     sdata->control_port_over_nl80211)) {
2406 		struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2407 		bool noencrypt = status->flag & RX_FLAG_DECRYPTED;
2408 
2409 		cfg80211_rx_control_port(dev, skb, noencrypt);
2410 		dev_kfree_skb(skb);
2411 	} else {
2412 		/* deliver to local stack */
2413 		if (rx->napi)
2414 			napi_gro_receive(rx->napi, skb);
2415 		else
2416 			netif_receive_skb(skb);
2417 	}
2418 }
2419 
2420 /*
2421  * requires that rx->skb is a frame with ethernet header
2422  */
2423 static void
2424 ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
2425 {
2426 	struct ieee80211_sub_if_data *sdata = rx->sdata;
2427 	struct net_device *dev = sdata->dev;
2428 	struct sk_buff *skb, *xmit_skb;
2429 	struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
2430 	struct sta_info *dsta;
2431 
2432 	skb = rx->skb;
2433 	xmit_skb = NULL;
2434 
2435 	ieee80211_rx_stats(dev, skb->len);
2436 
2437 	if (rx->sta) {
2438 		/* The seqno index has the same property as needed
2439 		 * for the rx_msdu field, i.e. it is IEEE80211_NUM_TIDS
2440 		 * for non-QoS-data frames. Here we know it's a data
2441 		 * frame, so count MSDUs.
2442 		 */
2443 		u64_stats_update_begin(&rx->sta->rx_stats.syncp);
2444 		rx->sta->rx_stats.msdu[rx->seqno_idx]++;
2445 		u64_stats_update_end(&rx->sta->rx_stats.syncp);
2446 	}
2447 
2448 	if ((sdata->vif.type == NL80211_IFTYPE_AP ||
2449 	     sdata->vif.type == NL80211_IFTYPE_AP_VLAN) &&
2450 	    !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) &&
2451 	    (sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->u.vlan.sta)) {
2452 		if (is_multicast_ether_addr(ehdr->h_dest) &&
2453 		    ieee80211_vif_get_num_mcast_if(sdata) != 0) {
2454 			/*
2455 			 * send multicast frames both to higher layers in
2456 			 * local net stack and back to the wireless medium
2457 			 */
2458 			xmit_skb = skb_copy(skb, GFP_ATOMIC);
2459 			if (!xmit_skb)
2460 				net_info_ratelimited("%s: failed to clone multicast frame\n",
2461 						    dev->name);
2462 		} else if (!is_multicast_ether_addr(ehdr->h_dest) &&
2463 			   !ether_addr_equal(ehdr->h_dest, ehdr->h_source)) {
2464 			dsta = sta_info_get(sdata, ehdr->h_dest);
2465 			if (dsta) {
2466 				/*
2467 				 * The destination station is associated to
2468 				 * this AP (in this VLAN), so send the frame
2469 				 * directly to it and do not pass it to local
2470 				 * net stack.
2471 				 */
2472 				xmit_skb = skb;
2473 				skb = NULL;
2474 			}
2475 		}
2476 	}
2477 
2478 #ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
2479 	if (skb) {
2480 		/* 'align' will only take the values 0 or 2 here since all
2481 		 * frames are required to be aligned to 2-byte boundaries
2482 		 * when being passed to mac80211; the code here works just
2483 		 * as well if that isn't true, but mac80211 assumes it can
2484 		 * access fields as 2-byte aligned (e.g. for ether_addr_equal)
2485 		 */
2486 		int align;
2487 
2488 		align = (unsigned long)(skb->data + sizeof(struct ethhdr)) & 3;
2489 		if (align) {
2490 			if (WARN_ON(skb_headroom(skb) < 3)) {
2491 				dev_kfree_skb(skb);
2492 				skb = NULL;
2493 			} else {
2494 				u8 *data = skb->data;
2495 				size_t len = skb_headlen(skb);
2496 				skb->data -= align;
2497 				memmove(skb->data, data, len);
2498 				skb_set_tail_pointer(skb, len);
2499 			}
2500 		}
2501 	}
2502 #endif
2503 
2504 	if (skb) {
2505 		skb->protocol = eth_type_trans(skb, dev);
2506 		memset(skb->cb, 0, sizeof(skb->cb));
2507 
2508 		ieee80211_deliver_skb_to_local_stack(skb, rx);
2509 	}
2510 
2511 	if (xmit_skb) {
2512 		/*
2513 		 * Send to wireless media and increase priority by 256 to
2514 		 * keep the received priority instead of reclassifying
2515 		 * the frame (see cfg80211_classify8021d).
2516 		 */
2517 		xmit_skb->priority += 256;
2518 		xmit_skb->protocol = htons(ETH_P_802_3);
2519 		skb_reset_network_header(xmit_skb);
2520 		skb_reset_mac_header(xmit_skb);
2521 		dev_queue_xmit(xmit_skb);
2522 	}
2523 }
2524 
2525 static ieee80211_rx_result debug_noinline
2526 __ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx, u8 data_offset)
2527 {
2528 	struct net_device *dev = rx->sdata->dev;
2529 	struct sk_buff *skb = rx->skb;
2530 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
2531 	__le16 fc = hdr->frame_control;
2532 	struct sk_buff_head frame_list;
2533 	struct ethhdr ethhdr;
2534 	const u8 *check_da = ethhdr.h_dest, *check_sa = ethhdr.h_source;
2535 
2536 	if (unlikely(ieee80211_has_a4(hdr->frame_control))) {
2537 		check_da = NULL;
2538 		check_sa = NULL;
2539 	} else switch (rx->sdata->vif.type) {
2540 		case NL80211_IFTYPE_AP:
2541 		case NL80211_IFTYPE_AP_VLAN:
2542 			check_da = NULL;
2543 			break;
2544 		case NL80211_IFTYPE_STATION:
2545 			if (!rx->sta ||
2546 			    !test_sta_flag(rx->sta, WLAN_STA_TDLS_PEER))
2547 				check_sa = NULL;
2548 			break;
2549 		case NL80211_IFTYPE_MESH_POINT:
2550 			check_sa = NULL;
2551 			break;
2552 		default:
2553 			break;
2554 	}
2555 
2556 	skb->dev = dev;
2557 	__skb_queue_head_init(&frame_list);
2558 
2559 	if (ieee80211_data_to_8023_exthdr(skb, &ethhdr,
2560 					  rx->sdata->vif.addr,
2561 					  rx->sdata->vif.type,
2562 					  data_offset))
2563 		return RX_DROP_UNUSABLE;
2564 
2565 	ieee80211_amsdu_to_8023s(skb, &frame_list, dev->dev_addr,
2566 				 rx->sdata->vif.type,
2567 				 rx->local->hw.extra_tx_headroom,
2568 				 check_da, check_sa);
2569 
2570 	while (!skb_queue_empty(&frame_list)) {
2571 		rx->skb = __skb_dequeue(&frame_list);
2572 
2573 		if (!ieee80211_frame_allowed(rx, fc)) {
2574 			dev_kfree_skb(rx->skb);
2575 			continue;
2576 		}
2577 
2578 		ieee80211_deliver_skb(rx);
2579 	}
2580 
2581 	return RX_QUEUED;
2582 }
2583 
2584 static ieee80211_rx_result debug_noinline
2585 ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx)
2586 {
2587 	struct sk_buff *skb = rx->skb;
2588 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2589 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
2590 	__le16 fc = hdr->frame_control;
2591 
2592 	if (!(status->rx_flags & IEEE80211_RX_AMSDU))
2593 		return RX_CONTINUE;
2594 
2595 	if (unlikely(!ieee80211_is_data(fc)))
2596 		return RX_CONTINUE;
2597 
2598 	if (unlikely(!ieee80211_is_data_present(fc)))
2599 		return RX_DROP_MONITOR;
2600 
2601 	if (unlikely(ieee80211_has_a4(hdr->frame_control))) {
2602 		switch (rx->sdata->vif.type) {
2603 		case NL80211_IFTYPE_AP_VLAN:
2604 			if (!rx->sdata->u.vlan.sta)
2605 				return RX_DROP_UNUSABLE;
2606 			break;
2607 		case NL80211_IFTYPE_STATION:
2608 			if (!rx->sdata->u.mgd.use_4addr)
2609 				return RX_DROP_UNUSABLE;
2610 			break;
2611 		default:
2612 			return RX_DROP_UNUSABLE;
2613 		}
2614 	}
2615 
2616 	if (is_multicast_ether_addr(hdr->addr1))
2617 		return RX_DROP_UNUSABLE;
2618 
2619 	return __ieee80211_rx_h_amsdu(rx, 0);
2620 }
2621 
2622 #ifdef CONFIG_MAC80211_MESH
2623 static ieee80211_rx_result
2624 ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx)
2625 {
2626 	struct ieee80211_hdr *fwd_hdr, *hdr;
2627 	struct ieee80211_tx_info *info;
2628 	struct ieee80211s_hdr *mesh_hdr;
2629 	struct sk_buff *skb = rx->skb, *fwd_skb;
2630 	struct ieee80211_local *local = rx->local;
2631 	struct ieee80211_sub_if_data *sdata = rx->sdata;
2632 	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
2633 	u16 ac, q, hdrlen;
2634 
2635 	hdr = (struct ieee80211_hdr *) skb->data;
2636 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
2637 
2638 	/* make sure fixed part of mesh header is there, also checks skb len */
2639 	if (!pskb_may_pull(rx->skb, hdrlen + 6))
2640 		return RX_DROP_MONITOR;
2641 
2642 	mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
2643 
2644 	/* make sure full mesh header is there, also checks skb len */
2645 	if (!pskb_may_pull(rx->skb,
2646 			   hdrlen + ieee80211_get_mesh_hdrlen(mesh_hdr)))
2647 		return RX_DROP_MONITOR;
2648 
2649 	/* reload pointers */
2650 	hdr = (struct ieee80211_hdr *) skb->data;
2651 	mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
2652 
2653 	if (ieee80211_drop_unencrypted(rx, hdr->frame_control))
2654 		return RX_DROP_MONITOR;
2655 
2656 	/* frame is in RMC, don't forward */
2657 	if (ieee80211_is_data(hdr->frame_control) &&
2658 	    is_multicast_ether_addr(hdr->addr1) &&
2659 	    mesh_rmc_check(rx->sdata, hdr->addr3, mesh_hdr))
2660 		return RX_DROP_MONITOR;
2661 
2662 	if (!ieee80211_is_data(hdr->frame_control))
2663 		return RX_CONTINUE;
2664 
2665 	if (!mesh_hdr->ttl)
2666 		return RX_DROP_MONITOR;
2667 
2668 	if (mesh_hdr->flags & MESH_FLAGS_AE) {
2669 		struct mesh_path *mppath;
2670 		char *proxied_addr;
2671 		char *mpp_addr;
2672 
2673 		if (is_multicast_ether_addr(hdr->addr1)) {
2674 			mpp_addr = hdr->addr3;
2675 			proxied_addr = mesh_hdr->eaddr1;
2676 		} else if ((mesh_hdr->flags & MESH_FLAGS_AE) ==
2677 			    MESH_FLAGS_AE_A5_A6) {
2678 			/* has_a4 already checked in ieee80211_rx_mesh_check */
2679 			mpp_addr = hdr->addr4;
2680 			proxied_addr = mesh_hdr->eaddr2;
2681 		} else {
2682 			return RX_DROP_MONITOR;
2683 		}
2684 
2685 		rcu_read_lock();
2686 		mppath = mpp_path_lookup(sdata, proxied_addr);
2687 		if (!mppath) {
2688 			mpp_path_add(sdata, proxied_addr, mpp_addr);
2689 		} else {
2690 			spin_lock_bh(&mppath->state_lock);
2691 			if (!ether_addr_equal(mppath->mpp, mpp_addr))
2692 				memcpy(mppath->mpp, mpp_addr, ETH_ALEN);
2693 			mppath->exp_time = jiffies;
2694 			spin_unlock_bh(&mppath->state_lock);
2695 		}
2696 		rcu_read_unlock();
2697 	}
2698 
2699 	/* Frame has reached destination.  Don't forward */
2700 	if (!is_multicast_ether_addr(hdr->addr1) &&
2701 	    ether_addr_equal(sdata->vif.addr, hdr->addr3))
2702 		return RX_CONTINUE;
2703 
2704 	ac = ieee80211_select_queue_80211(sdata, skb, hdr);
2705 	q = sdata->vif.hw_queue[ac];
2706 	if (ieee80211_queue_stopped(&local->hw, q)) {
2707 		IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_congestion);
2708 		return RX_DROP_MONITOR;
2709 	}
2710 	skb_set_queue_mapping(skb, q);
2711 
2712 	if (!--mesh_hdr->ttl) {
2713 		IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_ttl);
2714 		goto out;
2715 	}
2716 
2717 	if (!ifmsh->mshcfg.dot11MeshForwarding)
2718 		goto out;
2719 
2720 	fwd_skb = skb_copy_expand(skb, local->tx_headroom +
2721 				       sdata->encrypt_headroom, 0, GFP_ATOMIC);
2722 	if (!fwd_skb)
2723 		goto out;
2724 
2725 	fwd_hdr =  (struct ieee80211_hdr *) fwd_skb->data;
2726 	fwd_hdr->frame_control &= ~cpu_to_le16(IEEE80211_FCTL_RETRY);
2727 	info = IEEE80211_SKB_CB(fwd_skb);
2728 	memset(info, 0, sizeof(*info));
2729 	info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
2730 	info->control.vif = &rx->sdata->vif;
2731 	info->control.jiffies = jiffies;
2732 	if (is_multicast_ether_addr(fwd_hdr->addr1)) {
2733 		IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_mcast);
2734 		memcpy(fwd_hdr->addr2, sdata->vif.addr, ETH_ALEN);
2735 		/* update power mode indication when forwarding */
2736 		ieee80211_mps_set_frame_flags(sdata, NULL, fwd_hdr);
2737 	} else if (!mesh_nexthop_lookup(sdata, fwd_skb)) {
2738 		/* mesh power mode flags updated in mesh_nexthop_lookup */
2739 		IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_unicast);
2740 	} else {
2741 		/* unable to resolve next hop */
2742 		mesh_path_error_tx(sdata, ifmsh->mshcfg.element_ttl,
2743 				   fwd_hdr->addr3, 0,
2744 				   WLAN_REASON_MESH_PATH_NOFORWARD,
2745 				   fwd_hdr->addr2);
2746 		IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_no_route);
2747 		kfree_skb(fwd_skb);
2748 		return RX_DROP_MONITOR;
2749 	}
2750 
2751 	IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_frames);
2752 	ieee80211_add_pending_skb(local, fwd_skb);
2753  out:
2754 	if (is_multicast_ether_addr(hdr->addr1))
2755 		return RX_CONTINUE;
2756 	return RX_DROP_MONITOR;
2757 }
2758 #endif
2759 
2760 static ieee80211_rx_result debug_noinline
2761 ieee80211_rx_h_data(struct ieee80211_rx_data *rx)
2762 {
2763 	struct ieee80211_sub_if_data *sdata = rx->sdata;
2764 	struct ieee80211_local *local = rx->local;
2765 	struct net_device *dev = sdata->dev;
2766 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
2767 	__le16 fc = hdr->frame_control;
2768 	bool port_control;
2769 	int err;
2770 
2771 	if (unlikely(!ieee80211_is_data(hdr->frame_control)))
2772 		return RX_CONTINUE;
2773 
2774 	if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
2775 		return RX_DROP_MONITOR;
2776 
2777 	/*
2778 	 * Send unexpected-4addr-frame event to hostapd. For older versions,
2779 	 * also drop the frame to cooked monitor interfaces.
2780 	 */
2781 	if (ieee80211_has_a4(hdr->frame_control) &&
2782 	    sdata->vif.type == NL80211_IFTYPE_AP) {
2783 		if (rx->sta &&
2784 		    !test_and_set_sta_flag(rx->sta, WLAN_STA_4ADDR_EVENT))
2785 			cfg80211_rx_unexpected_4addr_frame(
2786 				rx->sdata->dev, rx->sta->sta.addr, GFP_ATOMIC);
2787 		return RX_DROP_MONITOR;
2788 	}
2789 
2790 	err = __ieee80211_data_to_8023(rx, &port_control);
2791 	if (unlikely(err))
2792 		return RX_DROP_UNUSABLE;
2793 
2794 	if (!ieee80211_frame_allowed(rx, fc))
2795 		return RX_DROP_MONITOR;
2796 
2797 	/* directly handle TDLS channel switch requests/responses */
2798 	if (unlikely(((struct ethhdr *)rx->skb->data)->h_proto ==
2799 						cpu_to_be16(ETH_P_TDLS))) {
2800 		struct ieee80211_tdls_data *tf = (void *)rx->skb->data;
2801 
2802 		if (pskb_may_pull(rx->skb,
2803 				  offsetof(struct ieee80211_tdls_data, u)) &&
2804 		    tf->payload_type == WLAN_TDLS_SNAP_RFTYPE &&
2805 		    tf->category == WLAN_CATEGORY_TDLS &&
2806 		    (tf->action_code == WLAN_TDLS_CHANNEL_SWITCH_REQUEST ||
2807 		     tf->action_code == WLAN_TDLS_CHANNEL_SWITCH_RESPONSE)) {
2808 			skb_queue_tail(&local->skb_queue_tdls_chsw, rx->skb);
2809 			schedule_work(&local->tdls_chsw_work);
2810 			if (rx->sta)
2811 				rx->sta->rx_stats.packets++;
2812 
2813 			return RX_QUEUED;
2814 		}
2815 	}
2816 
2817 	if (rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
2818 	    unlikely(port_control) && sdata->bss) {
2819 		sdata = container_of(sdata->bss, struct ieee80211_sub_if_data,
2820 				     u.ap);
2821 		dev = sdata->dev;
2822 		rx->sdata = sdata;
2823 	}
2824 
2825 	rx->skb->dev = dev;
2826 
2827 	if (!ieee80211_hw_check(&local->hw, SUPPORTS_DYNAMIC_PS) &&
2828 	    local->ps_sdata && local->hw.conf.dynamic_ps_timeout > 0 &&
2829 	    !is_multicast_ether_addr(
2830 		    ((struct ethhdr *)rx->skb->data)->h_dest) &&
2831 	    (!local->scanning &&
2832 	     !test_bit(SDATA_STATE_OFFCHANNEL, &sdata->state)))
2833 		mod_timer(&local->dynamic_ps_timer, jiffies +
2834 			  msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout));
2835 
2836 	ieee80211_deliver_skb(rx);
2837 
2838 	return RX_QUEUED;
2839 }
2840 
2841 static ieee80211_rx_result debug_noinline
2842 ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx, struct sk_buff_head *frames)
2843 {
2844 	struct sk_buff *skb = rx->skb;
2845 	struct ieee80211_bar *bar = (struct ieee80211_bar *)skb->data;
2846 	struct tid_ampdu_rx *tid_agg_rx;
2847 	u16 start_seq_num;
2848 	u16 tid;
2849 
2850 	if (likely(!ieee80211_is_ctl(bar->frame_control)))
2851 		return RX_CONTINUE;
2852 
2853 	if (ieee80211_is_back_req(bar->frame_control)) {
2854 		struct {
2855 			__le16 control, start_seq_num;
2856 		} __packed bar_data;
2857 		struct ieee80211_event event = {
2858 			.type = BAR_RX_EVENT,
2859 		};
2860 
2861 		if (!rx->sta)
2862 			return RX_DROP_MONITOR;
2863 
2864 		if (skb_copy_bits(skb, offsetof(struct ieee80211_bar, control),
2865 				  &bar_data, sizeof(bar_data)))
2866 			return RX_DROP_MONITOR;
2867 
2868 		tid = le16_to_cpu(bar_data.control) >> 12;
2869 
2870 		if (!test_bit(tid, rx->sta->ampdu_mlme.agg_session_valid) &&
2871 		    !test_and_set_bit(tid, rx->sta->ampdu_mlme.unexpected_agg))
2872 			ieee80211_send_delba(rx->sdata, rx->sta->sta.addr, tid,
2873 					     WLAN_BACK_RECIPIENT,
2874 					     WLAN_REASON_QSTA_REQUIRE_SETUP);
2875 
2876 		tid_agg_rx = rcu_dereference(rx->sta->ampdu_mlme.tid_rx[tid]);
2877 		if (!tid_agg_rx)
2878 			return RX_DROP_MONITOR;
2879 
2880 		start_seq_num = le16_to_cpu(bar_data.start_seq_num) >> 4;
2881 		event.u.ba.tid = tid;
2882 		event.u.ba.ssn = start_seq_num;
2883 		event.u.ba.sta = &rx->sta->sta;
2884 
2885 		/* reset session timer */
2886 		if (tid_agg_rx->timeout)
2887 			mod_timer(&tid_agg_rx->session_timer,
2888 				  TU_TO_EXP_TIME(tid_agg_rx->timeout));
2889 
2890 		spin_lock(&tid_agg_rx->reorder_lock);
2891 		/* release stored frames up to start of BAR */
2892 		ieee80211_release_reorder_frames(rx->sdata, tid_agg_rx,
2893 						 start_seq_num, frames);
2894 		spin_unlock(&tid_agg_rx->reorder_lock);
2895 
2896 		drv_event_callback(rx->local, rx->sdata, &event);
2897 
2898 		kfree_skb(skb);
2899 		return RX_QUEUED;
2900 	}
2901 
2902 	/*
2903 	 * After this point, we only want management frames,
2904 	 * so we can drop all remaining control frames to
2905 	 * cooked monitor interfaces.
2906 	 */
2907 	return RX_DROP_MONITOR;
2908 }
2909 
2910 static void ieee80211_process_sa_query_req(struct ieee80211_sub_if_data *sdata,
2911 					   struct ieee80211_mgmt *mgmt,
2912 					   size_t len)
2913 {
2914 	struct ieee80211_local *local = sdata->local;
2915 	struct sk_buff *skb;
2916 	struct ieee80211_mgmt *resp;
2917 
2918 	if (!ether_addr_equal(mgmt->da, sdata->vif.addr)) {
2919 		/* Not to own unicast address */
2920 		return;
2921 	}
2922 
2923 	if (!ether_addr_equal(mgmt->sa, sdata->u.mgd.bssid) ||
2924 	    !ether_addr_equal(mgmt->bssid, sdata->u.mgd.bssid)) {
2925 		/* Not from the current AP or not associated yet. */
2926 		return;
2927 	}
2928 
2929 	if (len < 24 + 1 + sizeof(resp->u.action.u.sa_query)) {
2930 		/* Too short SA Query request frame */
2931 		return;
2932 	}
2933 
2934 	skb = dev_alloc_skb(sizeof(*resp) + local->hw.extra_tx_headroom);
2935 	if (skb == NULL)
2936 		return;
2937 
2938 	skb_reserve(skb, local->hw.extra_tx_headroom);
2939 	resp = skb_put_zero(skb, 24);
2940 	memcpy(resp->da, mgmt->sa, ETH_ALEN);
2941 	memcpy(resp->sa, sdata->vif.addr, ETH_ALEN);
2942 	memcpy(resp->bssid, sdata->u.mgd.bssid, ETH_ALEN);
2943 	resp->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
2944 					  IEEE80211_STYPE_ACTION);
2945 	skb_put(skb, 1 + sizeof(resp->u.action.u.sa_query));
2946 	resp->u.action.category = WLAN_CATEGORY_SA_QUERY;
2947 	resp->u.action.u.sa_query.action = WLAN_ACTION_SA_QUERY_RESPONSE;
2948 	memcpy(resp->u.action.u.sa_query.trans_id,
2949 	       mgmt->u.action.u.sa_query.trans_id,
2950 	       WLAN_SA_QUERY_TR_ID_LEN);
2951 
2952 	ieee80211_tx_skb(sdata, skb);
2953 }
2954 
2955 static ieee80211_rx_result debug_noinline
2956 ieee80211_rx_h_mgmt_check(struct ieee80211_rx_data *rx)
2957 {
2958 	struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2959 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2960 
2961 	/*
2962 	 * From here on, look only at management frames.
2963 	 * Data and control frames are already handled,
2964 	 * and unknown (reserved) frames are useless.
2965 	 */
2966 	if (rx->skb->len < 24)
2967 		return RX_DROP_MONITOR;
2968 
2969 	if (!ieee80211_is_mgmt(mgmt->frame_control))
2970 		return RX_DROP_MONITOR;
2971 
2972 	if (rx->sdata->vif.type == NL80211_IFTYPE_AP &&
2973 	    ieee80211_is_beacon(mgmt->frame_control) &&
2974 	    !(rx->flags & IEEE80211_RX_BEACON_REPORTED)) {
2975 		int sig = 0;
2976 
2977 		if (ieee80211_hw_check(&rx->local->hw, SIGNAL_DBM) &&
2978 		    !(status->flag & RX_FLAG_NO_SIGNAL_VAL))
2979 			sig = status->signal;
2980 
2981 		cfg80211_report_obss_beacon(rx->local->hw.wiphy,
2982 					    rx->skb->data, rx->skb->len,
2983 					    status->freq, sig);
2984 		rx->flags |= IEEE80211_RX_BEACON_REPORTED;
2985 	}
2986 
2987 	if (ieee80211_drop_unencrypted_mgmt(rx))
2988 		return RX_DROP_UNUSABLE;
2989 
2990 	return RX_CONTINUE;
2991 }
2992 
2993 static ieee80211_rx_result debug_noinline
2994 ieee80211_rx_h_action(struct ieee80211_rx_data *rx)
2995 {
2996 	struct ieee80211_local *local = rx->local;
2997 	struct ieee80211_sub_if_data *sdata = rx->sdata;
2998 	struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2999 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
3000 	int len = rx->skb->len;
3001 
3002 	if (!ieee80211_is_action(mgmt->frame_control))
3003 		return RX_CONTINUE;
3004 
3005 	/* drop too small frames */
3006 	if (len < IEEE80211_MIN_ACTION_SIZE)
3007 		return RX_DROP_UNUSABLE;
3008 
3009 	if (!rx->sta && mgmt->u.action.category != WLAN_CATEGORY_PUBLIC &&
3010 	    mgmt->u.action.category != WLAN_CATEGORY_SELF_PROTECTED &&
3011 	    mgmt->u.action.category != WLAN_CATEGORY_SPECTRUM_MGMT)
3012 		return RX_DROP_UNUSABLE;
3013 
3014 	switch (mgmt->u.action.category) {
3015 	case WLAN_CATEGORY_HT:
3016 		/* reject HT action frames from stations not supporting HT */
3017 		if (!rx->sta->sta.ht_cap.ht_supported)
3018 			goto invalid;
3019 
3020 		if (sdata->vif.type != NL80211_IFTYPE_STATION &&
3021 		    sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
3022 		    sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
3023 		    sdata->vif.type != NL80211_IFTYPE_AP &&
3024 		    sdata->vif.type != NL80211_IFTYPE_ADHOC)
3025 			break;
3026 
3027 		/* verify action & smps_control/chanwidth are present */
3028 		if (len < IEEE80211_MIN_ACTION_SIZE + 2)
3029 			goto invalid;
3030 
3031 		switch (mgmt->u.action.u.ht_smps.action) {
3032 		case WLAN_HT_ACTION_SMPS: {
3033 			struct ieee80211_supported_band *sband;
3034 			enum ieee80211_smps_mode smps_mode;
3035 			struct sta_opmode_info sta_opmode = {};
3036 
3037 			/* convert to HT capability */
3038 			switch (mgmt->u.action.u.ht_smps.smps_control) {
3039 			case WLAN_HT_SMPS_CONTROL_DISABLED:
3040 				smps_mode = IEEE80211_SMPS_OFF;
3041 				break;
3042 			case WLAN_HT_SMPS_CONTROL_STATIC:
3043 				smps_mode = IEEE80211_SMPS_STATIC;
3044 				break;
3045 			case WLAN_HT_SMPS_CONTROL_DYNAMIC:
3046 				smps_mode = IEEE80211_SMPS_DYNAMIC;
3047 				break;
3048 			default:
3049 				goto invalid;
3050 			}
3051 
3052 			/* if no change do nothing */
3053 			if (rx->sta->sta.smps_mode == smps_mode)
3054 				goto handled;
3055 			rx->sta->sta.smps_mode = smps_mode;
3056 			sta_opmode.smps_mode =
3057 				ieee80211_smps_mode_to_smps_mode(smps_mode);
3058 			sta_opmode.changed = STA_OPMODE_SMPS_MODE_CHANGED;
3059 
3060 			sband = rx->local->hw.wiphy->bands[status->band];
3061 
3062 			rate_control_rate_update(local, sband, rx->sta,
3063 						 IEEE80211_RC_SMPS_CHANGED);
3064 			cfg80211_sta_opmode_change_notify(sdata->dev,
3065 							  rx->sta->addr,
3066 							  &sta_opmode,
3067 							  GFP_ATOMIC);
3068 			goto handled;
3069 		}
3070 		case WLAN_HT_ACTION_NOTIFY_CHANWIDTH: {
3071 			struct ieee80211_supported_band *sband;
3072 			u8 chanwidth = mgmt->u.action.u.ht_notify_cw.chanwidth;
3073 			enum ieee80211_sta_rx_bandwidth max_bw, new_bw;
3074 			struct sta_opmode_info sta_opmode = {};
3075 
3076 			/* If it doesn't support 40 MHz it can't change ... */
3077 			if (!(rx->sta->sta.ht_cap.cap &
3078 					IEEE80211_HT_CAP_SUP_WIDTH_20_40))
3079 				goto handled;
3080 
3081 			if (chanwidth == IEEE80211_HT_CHANWIDTH_20MHZ)
3082 				max_bw = IEEE80211_STA_RX_BW_20;
3083 			else
3084 				max_bw = ieee80211_sta_cap_rx_bw(rx->sta);
3085 
3086 			/* set cur_max_bandwidth and recalc sta bw */
3087 			rx->sta->cur_max_bandwidth = max_bw;
3088 			new_bw = ieee80211_sta_cur_vht_bw(rx->sta);
3089 
3090 			if (rx->sta->sta.bandwidth == new_bw)
3091 				goto handled;
3092 
3093 			rx->sta->sta.bandwidth = new_bw;
3094 			sband = rx->local->hw.wiphy->bands[status->band];
3095 			sta_opmode.bw =
3096 				ieee80211_sta_rx_bw_to_chan_width(rx->sta);
3097 			sta_opmode.changed = STA_OPMODE_MAX_BW_CHANGED;
3098 
3099 			rate_control_rate_update(local, sband, rx->sta,
3100 						 IEEE80211_RC_BW_CHANGED);
3101 			cfg80211_sta_opmode_change_notify(sdata->dev,
3102 							  rx->sta->addr,
3103 							  &sta_opmode,
3104 							  GFP_ATOMIC);
3105 			goto handled;
3106 		}
3107 		default:
3108 			goto invalid;
3109 		}
3110 
3111 		break;
3112 	case WLAN_CATEGORY_PUBLIC:
3113 		if (len < IEEE80211_MIN_ACTION_SIZE + 1)
3114 			goto invalid;
3115 		if (sdata->vif.type != NL80211_IFTYPE_STATION)
3116 			break;
3117 		if (!rx->sta)
3118 			break;
3119 		if (!ether_addr_equal(mgmt->bssid, sdata->u.mgd.bssid))
3120 			break;
3121 		if (mgmt->u.action.u.ext_chan_switch.action_code !=
3122 				WLAN_PUB_ACTION_EXT_CHANSW_ANN)
3123 			break;
3124 		if (len < offsetof(struct ieee80211_mgmt,
3125 				   u.action.u.ext_chan_switch.variable))
3126 			goto invalid;
3127 		goto queue;
3128 	case WLAN_CATEGORY_VHT:
3129 		if (sdata->vif.type != NL80211_IFTYPE_STATION &&
3130 		    sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
3131 		    sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
3132 		    sdata->vif.type != NL80211_IFTYPE_AP &&
3133 		    sdata->vif.type != NL80211_IFTYPE_ADHOC)
3134 			break;
3135 
3136 		/* verify action code is present */
3137 		if (len < IEEE80211_MIN_ACTION_SIZE + 1)
3138 			goto invalid;
3139 
3140 		switch (mgmt->u.action.u.vht_opmode_notif.action_code) {
3141 		case WLAN_VHT_ACTION_OPMODE_NOTIF: {
3142 			/* verify opmode is present */
3143 			if (len < IEEE80211_MIN_ACTION_SIZE + 2)
3144 				goto invalid;
3145 			goto queue;
3146 		}
3147 		case WLAN_VHT_ACTION_GROUPID_MGMT: {
3148 			if (len < IEEE80211_MIN_ACTION_SIZE + 25)
3149 				goto invalid;
3150 			goto queue;
3151 		}
3152 		default:
3153 			break;
3154 		}
3155 		break;
3156 	case WLAN_CATEGORY_BACK:
3157 		if (sdata->vif.type != NL80211_IFTYPE_STATION &&
3158 		    sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
3159 		    sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
3160 		    sdata->vif.type != NL80211_IFTYPE_AP &&
3161 		    sdata->vif.type != NL80211_IFTYPE_ADHOC)
3162 			break;
3163 
3164 		/* verify action_code is present */
3165 		if (len < IEEE80211_MIN_ACTION_SIZE + 1)
3166 			break;
3167 
3168 		switch (mgmt->u.action.u.addba_req.action_code) {
3169 		case WLAN_ACTION_ADDBA_REQ:
3170 			if (len < (IEEE80211_MIN_ACTION_SIZE +
3171 				   sizeof(mgmt->u.action.u.addba_req)))
3172 				goto invalid;
3173 			break;
3174 		case WLAN_ACTION_ADDBA_RESP:
3175 			if (len < (IEEE80211_MIN_ACTION_SIZE +
3176 				   sizeof(mgmt->u.action.u.addba_resp)))
3177 				goto invalid;
3178 			break;
3179 		case WLAN_ACTION_DELBA:
3180 			if (len < (IEEE80211_MIN_ACTION_SIZE +
3181 				   sizeof(mgmt->u.action.u.delba)))
3182 				goto invalid;
3183 			break;
3184 		default:
3185 			goto invalid;
3186 		}
3187 
3188 		goto queue;
3189 	case WLAN_CATEGORY_SPECTRUM_MGMT:
3190 		/* verify action_code is present */
3191 		if (len < IEEE80211_MIN_ACTION_SIZE + 1)
3192 			break;
3193 
3194 		switch (mgmt->u.action.u.measurement.action_code) {
3195 		case WLAN_ACTION_SPCT_MSR_REQ:
3196 			if (status->band != NL80211_BAND_5GHZ)
3197 				break;
3198 
3199 			if (len < (IEEE80211_MIN_ACTION_SIZE +
3200 				   sizeof(mgmt->u.action.u.measurement)))
3201 				break;
3202 
3203 			if (sdata->vif.type != NL80211_IFTYPE_STATION)
3204 				break;
3205 
3206 			ieee80211_process_measurement_req(sdata, mgmt, len);
3207 			goto handled;
3208 		case WLAN_ACTION_SPCT_CHL_SWITCH: {
3209 			u8 *bssid;
3210 			if (len < (IEEE80211_MIN_ACTION_SIZE +
3211 				   sizeof(mgmt->u.action.u.chan_switch)))
3212 				break;
3213 
3214 			if (sdata->vif.type != NL80211_IFTYPE_STATION &&
3215 			    sdata->vif.type != NL80211_IFTYPE_ADHOC &&
3216 			    sdata->vif.type != NL80211_IFTYPE_MESH_POINT)
3217 				break;
3218 
3219 			if (sdata->vif.type == NL80211_IFTYPE_STATION)
3220 				bssid = sdata->u.mgd.bssid;
3221 			else if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
3222 				bssid = sdata->u.ibss.bssid;
3223 			else if (sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
3224 				bssid = mgmt->sa;
3225 			else
3226 				break;
3227 
3228 			if (!ether_addr_equal(mgmt->bssid, bssid))
3229 				break;
3230 
3231 			goto queue;
3232 			}
3233 		}
3234 		break;
3235 	case WLAN_CATEGORY_SA_QUERY:
3236 		if (len < (IEEE80211_MIN_ACTION_SIZE +
3237 			   sizeof(mgmt->u.action.u.sa_query)))
3238 			break;
3239 
3240 		switch (mgmt->u.action.u.sa_query.action) {
3241 		case WLAN_ACTION_SA_QUERY_REQUEST:
3242 			if (sdata->vif.type != NL80211_IFTYPE_STATION)
3243 				break;
3244 			ieee80211_process_sa_query_req(sdata, mgmt, len);
3245 			goto handled;
3246 		}
3247 		break;
3248 	case WLAN_CATEGORY_SELF_PROTECTED:
3249 		if (len < (IEEE80211_MIN_ACTION_SIZE +
3250 			   sizeof(mgmt->u.action.u.self_prot.action_code)))
3251 			break;
3252 
3253 		switch (mgmt->u.action.u.self_prot.action_code) {
3254 		case WLAN_SP_MESH_PEERING_OPEN:
3255 		case WLAN_SP_MESH_PEERING_CLOSE:
3256 		case WLAN_SP_MESH_PEERING_CONFIRM:
3257 			if (!ieee80211_vif_is_mesh(&sdata->vif))
3258 				goto invalid;
3259 			if (sdata->u.mesh.user_mpm)
3260 				/* userspace handles this frame */
3261 				break;
3262 			goto queue;
3263 		case WLAN_SP_MGK_INFORM:
3264 		case WLAN_SP_MGK_ACK:
3265 			if (!ieee80211_vif_is_mesh(&sdata->vif))
3266 				goto invalid;
3267 			break;
3268 		}
3269 		break;
3270 	case WLAN_CATEGORY_MESH_ACTION:
3271 		if (len < (IEEE80211_MIN_ACTION_SIZE +
3272 			   sizeof(mgmt->u.action.u.mesh_action.action_code)))
3273 			break;
3274 
3275 		if (!ieee80211_vif_is_mesh(&sdata->vif))
3276 			break;
3277 		if (mesh_action_is_path_sel(mgmt) &&
3278 		    !mesh_path_sel_is_hwmp(sdata))
3279 			break;
3280 		goto queue;
3281 	}
3282 
3283 	return RX_CONTINUE;
3284 
3285  invalid:
3286 	status->rx_flags |= IEEE80211_RX_MALFORMED_ACTION_FRM;
3287 	/* will return in the next handlers */
3288 	return RX_CONTINUE;
3289 
3290  handled:
3291 	if (rx->sta)
3292 		rx->sta->rx_stats.packets++;
3293 	dev_kfree_skb(rx->skb);
3294 	return RX_QUEUED;
3295 
3296  queue:
3297 	skb_queue_tail(&sdata->skb_queue, rx->skb);
3298 	ieee80211_queue_work(&local->hw, &sdata->work);
3299 	if (rx->sta)
3300 		rx->sta->rx_stats.packets++;
3301 	return RX_QUEUED;
3302 }
3303 
3304 static ieee80211_rx_result debug_noinline
3305 ieee80211_rx_h_userspace_mgmt(struct ieee80211_rx_data *rx)
3306 {
3307 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
3308 	int sig = 0;
3309 
3310 	/* skip known-bad action frames and return them in the next handler */
3311 	if (status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM)
3312 		return RX_CONTINUE;
3313 
3314 	/*
3315 	 * Getting here means the kernel doesn't know how to handle
3316 	 * it, but maybe userspace does ... include returned frames
3317 	 * so userspace can register for those to know whether ones
3318 	 * it transmitted were processed or returned.
3319 	 */
3320 
3321 	if (ieee80211_hw_check(&rx->local->hw, SIGNAL_DBM) &&
3322 	    !(status->flag & RX_FLAG_NO_SIGNAL_VAL))
3323 		sig = status->signal;
3324 
3325 	if (cfg80211_rx_mgmt(&rx->sdata->wdev, status->freq, sig,
3326 			     rx->skb->data, rx->skb->len, 0)) {
3327 		if (rx->sta)
3328 			rx->sta->rx_stats.packets++;
3329 		dev_kfree_skb(rx->skb);
3330 		return RX_QUEUED;
3331 	}
3332 
3333 	return RX_CONTINUE;
3334 }
3335 
3336 static ieee80211_rx_result debug_noinline
3337 ieee80211_rx_h_action_return(struct ieee80211_rx_data *rx)
3338 {
3339 	struct ieee80211_local *local = rx->local;
3340 	struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
3341 	struct sk_buff *nskb;
3342 	struct ieee80211_sub_if_data *sdata = rx->sdata;
3343 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
3344 
3345 	if (!ieee80211_is_action(mgmt->frame_control))
3346 		return RX_CONTINUE;
3347 
3348 	/*
3349 	 * For AP mode, hostapd is responsible for handling any action
3350 	 * frames that we didn't handle, including returning unknown
3351 	 * ones. For all other modes we will return them to the sender,
3352 	 * setting the 0x80 bit in the action category, as required by
3353 	 * 802.11-2012 9.24.4.
3354 	 * Newer versions of hostapd shall also use the management frame
3355 	 * registration mechanisms, but older ones still use cooked
3356 	 * monitor interfaces so push all frames there.
3357 	 */
3358 	if (!(status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM) &&
3359 	    (sdata->vif.type == NL80211_IFTYPE_AP ||
3360 	     sdata->vif.type == NL80211_IFTYPE_AP_VLAN))
3361 		return RX_DROP_MONITOR;
3362 
3363 	if (is_multicast_ether_addr(mgmt->da))
3364 		return RX_DROP_MONITOR;
3365 
3366 	/* do not return rejected action frames */
3367 	if (mgmt->u.action.category & 0x80)
3368 		return RX_DROP_UNUSABLE;
3369 
3370 	nskb = skb_copy_expand(rx->skb, local->hw.extra_tx_headroom, 0,
3371 			       GFP_ATOMIC);
3372 	if (nskb) {
3373 		struct ieee80211_mgmt *nmgmt = (void *)nskb->data;
3374 
3375 		nmgmt->u.action.category |= 0x80;
3376 		memcpy(nmgmt->da, nmgmt->sa, ETH_ALEN);
3377 		memcpy(nmgmt->sa, rx->sdata->vif.addr, ETH_ALEN);
3378 
3379 		memset(nskb->cb, 0, sizeof(nskb->cb));
3380 
3381 		if (rx->sdata->vif.type == NL80211_IFTYPE_P2P_DEVICE) {
3382 			struct ieee80211_tx_info *info = IEEE80211_SKB_CB(nskb);
3383 
3384 			info->flags = IEEE80211_TX_CTL_TX_OFFCHAN |
3385 				      IEEE80211_TX_INTFL_OFFCHAN_TX_OK |
3386 				      IEEE80211_TX_CTL_NO_CCK_RATE;
3387 			if (ieee80211_hw_check(&local->hw, QUEUE_CONTROL))
3388 				info->hw_queue =
3389 					local->hw.offchannel_tx_hw_queue;
3390 		}
3391 
3392 		__ieee80211_tx_skb_tid_band(rx->sdata, nskb, 7,
3393 					    status->band, 0);
3394 	}
3395 	dev_kfree_skb(rx->skb);
3396 	return RX_QUEUED;
3397 }
3398 
3399 static ieee80211_rx_result debug_noinline
3400 ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx)
3401 {
3402 	struct ieee80211_sub_if_data *sdata = rx->sdata;
3403 	struct ieee80211_mgmt *mgmt = (void *)rx->skb->data;
3404 	__le16 stype;
3405 
3406 	stype = mgmt->frame_control & cpu_to_le16(IEEE80211_FCTL_STYPE);
3407 
3408 	if (!ieee80211_vif_is_mesh(&sdata->vif) &&
3409 	    sdata->vif.type != NL80211_IFTYPE_ADHOC &&
3410 	    sdata->vif.type != NL80211_IFTYPE_OCB &&
3411 	    sdata->vif.type != NL80211_IFTYPE_STATION)
3412 		return RX_DROP_MONITOR;
3413 
3414 	switch (stype) {
3415 	case cpu_to_le16(IEEE80211_STYPE_AUTH):
3416 	case cpu_to_le16(IEEE80211_STYPE_BEACON):
3417 	case cpu_to_le16(IEEE80211_STYPE_PROBE_RESP):
3418 		/* process for all: mesh, mlme, ibss */
3419 		break;
3420 	case cpu_to_le16(IEEE80211_STYPE_ASSOC_RESP):
3421 	case cpu_to_le16(IEEE80211_STYPE_REASSOC_RESP):
3422 	case cpu_to_le16(IEEE80211_STYPE_DEAUTH):
3423 	case cpu_to_le16(IEEE80211_STYPE_DISASSOC):
3424 		if (is_multicast_ether_addr(mgmt->da) &&
3425 		    !is_broadcast_ether_addr(mgmt->da))
3426 			return RX_DROP_MONITOR;
3427 
3428 		/* process only for station */
3429 		if (sdata->vif.type != NL80211_IFTYPE_STATION)
3430 			return RX_DROP_MONITOR;
3431 		break;
3432 	case cpu_to_le16(IEEE80211_STYPE_PROBE_REQ):
3433 		/* process only for ibss and mesh */
3434 		if (sdata->vif.type != NL80211_IFTYPE_ADHOC &&
3435 		    sdata->vif.type != NL80211_IFTYPE_MESH_POINT)
3436 			return RX_DROP_MONITOR;
3437 		break;
3438 	default:
3439 		return RX_DROP_MONITOR;
3440 	}
3441 
3442 	/* queue up frame and kick off work to process it */
3443 	skb_queue_tail(&sdata->skb_queue, rx->skb);
3444 	ieee80211_queue_work(&rx->local->hw, &sdata->work);
3445 	if (rx->sta)
3446 		rx->sta->rx_stats.packets++;
3447 
3448 	return RX_QUEUED;
3449 }
3450 
3451 static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx,
3452 					struct ieee80211_rate *rate)
3453 {
3454 	struct ieee80211_sub_if_data *sdata;
3455 	struct ieee80211_local *local = rx->local;
3456 	struct sk_buff *skb = rx->skb, *skb2;
3457 	struct net_device *prev_dev = NULL;
3458 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
3459 	int needed_headroom;
3460 
3461 	/*
3462 	 * If cooked monitor has been processed already, then
3463 	 * don't do it again. If not, set the flag.
3464 	 */
3465 	if (rx->flags & IEEE80211_RX_CMNTR)
3466 		goto out_free_skb;
3467 	rx->flags |= IEEE80211_RX_CMNTR;
3468 
3469 	/* If there are no cooked monitor interfaces, just free the SKB */
3470 	if (!local->cooked_mntrs)
3471 		goto out_free_skb;
3472 
3473 	/* vendor data is long removed here */
3474 	status->flag &= ~RX_FLAG_RADIOTAP_VENDOR_DATA;
3475 	/* room for the radiotap header based on driver features */
3476 	needed_headroom = ieee80211_rx_radiotap_hdrlen(local, status, skb);
3477 
3478 	if (skb_headroom(skb) < needed_headroom &&
3479 	    pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC))
3480 		goto out_free_skb;
3481 
3482 	/* prepend radiotap information */
3483 	ieee80211_add_rx_radiotap_header(local, skb, rate, needed_headroom,
3484 					 false);
3485 
3486 	skb_reset_mac_header(skb);
3487 	skb->ip_summed = CHECKSUM_UNNECESSARY;
3488 	skb->pkt_type = PACKET_OTHERHOST;
3489 	skb->protocol = htons(ETH_P_802_2);
3490 
3491 	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
3492 		if (!ieee80211_sdata_running(sdata))
3493 			continue;
3494 
3495 		if (sdata->vif.type != NL80211_IFTYPE_MONITOR ||
3496 		    !(sdata->u.mntr.flags & MONITOR_FLAG_COOK_FRAMES))
3497 			continue;
3498 
3499 		if (prev_dev) {
3500 			skb2 = skb_clone(skb, GFP_ATOMIC);
3501 			if (skb2) {
3502 				skb2->dev = prev_dev;
3503 				netif_receive_skb(skb2);
3504 			}
3505 		}
3506 
3507 		prev_dev = sdata->dev;
3508 		ieee80211_rx_stats(sdata->dev, skb->len);
3509 	}
3510 
3511 	if (prev_dev) {
3512 		skb->dev = prev_dev;
3513 		netif_receive_skb(skb);
3514 		return;
3515 	}
3516 
3517  out_free_skb:
3518 	dev_kfree_skb(skb);
3519 }
3520 
3521 static void ieee80211_rx_handlers_result(struct ieee80211_rx_data *rx,
3522 					 ieee80211_rx_result res)
3523 {
3524 	switch (res) {
3525 	case RX_DROP_MONITOR:
3526 		I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop);
3527 		if (rx->sta)
3528 			rx->sta->rx_stats.dropped++;
3529 		/* fall through */
3530 	case RX_CONTINUE: {
3531 		struct ieee80211_rate *rate = NULL;
3532 		struct ieee80211_supported_band *sband;
3533 		struct ieee80211_rx_status *status;
3534 
3535 		status = IEEE80211_SKB_RXCB((rx->skb));
3536 
3537 		sband = rx->local->hw.wiphy->bands[status->band];
3538 		if (status->encoding == RX_ENC_LEGACY)
3539 			rate = &sband->bitrates[status->rate_idx];
3540 
3541 		ieee80211_rx_cooked_monitor(rx, rate);
3542 		break;
3543 		}
3544 	case RX_DROP_UNUSABLE:
3545 		I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop);
3546 		if (rx->sta)
3547 			rx->sta->rx_stats.dropped++;
3548 		dev_kfree_skb(rx->skb);
3549 		break;
3550 	case RX_QUEUED:
3551 		I802_DEBUG_INC(rx->sdata->local->rx_handlers_queued);
3552 		break;
3553 	}
3554 }
3555 
3556 static void ieee80211_rx_handlers(struct ieee80211_rx_data *rx,
3557 				  struct sk_buff_head *frames)
3558 {
3559 	ieee80211_rx_result res = RX_DROP_MONITOR;
3560 	struct sk_buff *skb;
3561 
3562 #define CALL_RXH(rxh)			\
3563 	do {				\
3564 		res = rxh(rx);		\
3565 		if (res != RX_CONTINUE)	\
3566 			goto rxh_next;  \
3567 	} while (0)
3568 
3569 	/* Lock here to avoid hitting all of the data used in the RX
3570 	 * path (e.g. key data, station data, ...) concurrently when
3571 	 * a frame is released from the reorder buffer due to timeout
3572 	 * from the timer, potentially concurrently with RX from the
3573 	 * driver.
3574 	 */
3575 	spin_lock_bh(&rx->local->rx_path_lock);
3576 
3577 	while ((skb = __skb_dequeue(frames))) {
3578 		/*
3579 		 * all the other fields are valid across frames
3580 		 * that belong to an aMPDU since they are on the
3581 		 * same TID from the same station
3582 		 */
3583 		rx->skb = skb;
3584 
3585 		CALL_RXH(ieee80211_rx_h_check_more_data);
3586 		CALL_RXH(ieee80211_rx_h_uapsd_and_pspoll);
3587 		CALL_RXH(ieee80211_rx_h_sta_process);
3588 		CALL_RXH(ieee80211_rx_h_decrypt);
3589 		CALL_RXH(ieee80211_rx_h_defragment);
3590 		CALL_RXH(ieee80211_rx_h_michael_mic_verify);
3591 		/* must be after MMIC verify so header is counted in MPDU mic */
3592 #ifdef CONFIG_MAC80211_MESH
3593 		if (ieee80211_vif_is_mesh(&rx->sdata->vif))
3594 			CALL_RXH(ieee80211_rx_h_mesh_fwding);
3595 #endif
3596 		CALL_RXH(ieee80211_rx_h_amsdu);
3597 		CALL_RXH(ieee80211_rx_h_data);
3598 
3599 		/* special treatment -- needs the queue */
3600 		res = ieee80211_rx_h_ctrl(rx, frames);
3601 		if (res != RX_CONTINUE)
3602 			goto rxh_next;
3603 
3604 		CALL_RXH(ieee80211_rx_h_mgmt_check);
3605 		CALL_RXH(ieee80211_rx_h_action);
3606 		CALL_RXH(ieee80211_rx_h_userspace_mgmt);
3607 		CALL_RXH(ieee80211_rx_h_action_return);
3608 		CALL_RXH(ieee80211_rx_h_mgmt);
3609 
3610  rxh_next:
3611 		ieee80211_rx_handlers_result(rx, res);
3612 
3613 #undef CALL_RXH
3614 	}
3615 
3616 	spin_unlock_bh(&rx->local->rx_path_lock);
3617 }
3618 
3619 static void ieee80211_invoke_rx_handlers(struct ieee80211_rx_data *rx)
3620 {
3621 	struct sk_buff_head reorder_release;
3622 	ieee80211_rx_result res = RX_DROP_MONITOR;
3623 
3624 	__skb_queue_head_init(&reorder_release);
3625 
3626 #define CALL_RXH(rxh)			\
3627 	do {				\
3628 		res = rxh(rx);		\
3629 		if (res != RX_CONTINUE)	\
3630 			goto rxh_next;  \
3631 	} while (0)
3632 
3633 	CALL_RXH(ieee80211_rx_h_check_dup);
3634 	CALL_RXH(ieee80211_rx_h_check);
3635 
3636 	ieee80211_rx_reorder_ampdu(rx, &reorder_release);
3637 
3638 	ieee80211_rx_handlers(rx, &reorder_release);
3639 	return;
3640 
3641  rxh_next:
3642 	ieee80211_rx_handlers_result(rx, res);
3643 
3644 #undef CALL_RXH
3645 }
3646 
3647 /*
3648  * This function makes calls into the RX path, therefore
3649  * it has to be invoked under RCU read lock.
3650  */
3651 void ieee80211_release_reorder_timeout(struct sta_info *sta, int tid)
3652 {
3653 	struct sk_buff_head frames;
3654 	struct ieee80211_rx_data rx = {
3655 		.sta = sta,
3656 		.sdata = sta->sdata,
3657 		.local = sta->local,
3658 		/* This is OK -- must be QoS data frame */
3659 		.security_idx = tid,
3660 		.seqno_idx = tid,
3661 		.napi = NULL, /* must be NULL to not have races */
3662 	};
3663 	struct tid_ampdu_rx *tid_agg_rx;
3664 
3665 	tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
3666 	if (!tid_agg_rx)
3667 		return;
3668 
3669 	__skb_queue_head_init(&frames);
3670 
3671 	spin_lock(&tid_agg_rx->reorder_lock);
3672 	ieee80211_sta_reorder_release(sta->sdata, tid_agg_rx, &frames);
3673 	spin_unlock(&tid_agg_rx->reorder_lock);
3674 
3675 	if (!skb_queue_empty(&frames)) {
3676 		struct ieee80211_event event = {
3677 			.type = BA_FRAME_TIMEOUT,
3678 			.u.ba.tid = tid,
3679 			.u.ba.sta = &sta->sta,
3680 		};
3681 		drv_event_callback(rx.local, rx.sdata, &event);
3682 	}
3683 
3684 	ieee80211_rx_handlers(&rx, &frames);
3685 }
3686 
3687 void ieee80211_mark_rx_ba_filtered_frames(struct ieee80211_sta *pubsta, u8 tid,
3688 					  u16 ssn, u64 filtered,
3689 					  u16 received_mpdus)
3690 {
3691 	struct sta_info *sta;
3692 	struct tid_ampdu_rx *tid_agg_rx;
3693 	struct sk_buff_head frames;
3694 	struct ieee80211_rx_data rx = {
3695 		/* This is OK -- must be QoS data frame */
3696 		.security_idx = tid,
3697 		.seqno_idx = tid,
3698 	};
3699 	int i, diff;
3700 
3701 	if (WARN_ON(!pubsta || tid >= IEEE80211_NUM_TIDS))
3702 		return;
3703 
3704 	__skb_queue_head_init(&frames);
3705 
3706 	sta = container_of(pubsta, struct sta_info, sta);
3707 
3708 	rx.sta = sta;
3709 	rx.sdata = sta->sdata;
3710 	rx.local = sta->local;
3711 
3712 	rcu_read_lock();
3713 	tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
3714 	if (!tid_agg_rx)
3715 		goto out;
3716 
3717 	spin_lock_bh(&tid_agg_rx->reorder_lock);
3718 
3719 	if (received_mpdus >= IEEE80211_SN_MODULO >> 1) {
3720 		int release;
3721 
3722 		/* release all frames in the reorder buffer */
3723 		release = (tid_agg_rx->head_seq_num + tid_agg_rx->buf_size) %
3724 			   IEEE80211_SN_MODULO;
3725 		ieee80211_release_reorder_frames(sta->sdata, tid_agg_rx,
3726 						 release, &frames);
3727 		/* update ssn to match received ssn */
3728 		tid_agg_rx->head_seq_num = ssn;
3729 	} else {
3730 		ieee80211_release_reorder_frames(sta->sdata, tid_agg_rx, ssn,
3731 						 &frames);
3732 	}
3733 
3734 	/* handle the case that received ssn is behind the mac ssn.
3735 	 * it can be tid_agg_rx->buf_size behind and still be valid */
3736 	diff = (tid_agg_rx->head_seq_num - ssn) & IEEE80211_SN_MASK;
3737 	if (diff >= tid_agg_rx->buf_size) {
3738 		tid_agg_rx->reorder_buf_filtered = 0;
3739 		goto release;
3740 	}
3741 	filtered = filtered >> diff;
3742 	ssn += diff;
3743 
3744 	/* update bitmap */
3745 	for (i = 0; i < tid_agg_rx->buf_size; i++) {
3746 		int index = (ssn + i) % tid_agg_rx->buf_size;
3747 
3748 		tid_agg_rx->reorder_buf_filtered &= ~BIT_ULL(index);
3749 		if (filtered & BIT_ULL(i))
3750 			tid_agg_rx->reorder_buf_filtered |= BIT_ULL(index);
3751 	}
3752 
3753 	/* now process also frames that the filter marking released */
3754 	ieee80211_sta_reorder_release(sta->sdata, tid_agg_rx, &frames);
3755 
3756 release:
3757 	spin_unlock_bh(&tid_agg_rx->reorder_lock);
3758 
3759 	ieee80211_rx_handlers(&rx, &frames);
3760 
3761  out:
3762 	rcu_read_unlock();
3763 }
3764 EXPORT_SYMBOL(ieee80211_mark_rx_ba_filtered_frames);
3765 
3766 /* main receive path */
3767 
3768 static bool ieee80211_accept_frame(struct ieee80211_rx_data *rx)
3769 {
3770 	struct ieee80211_sub_if_data *sdata = rx->sdata;
3771 	struct sk_buff *skb = rx->skb;
3772 	struct ieee80211_hdr *hdr = (void *)skb->data;
3773 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
3774 	u8 *bssid = ieee80211_get_bssid(hdr, skb->len, sdata->vif.type);
3775 	bool multicast = is_multicast_ether_addr(hdr->addr1);
3776 
3777 	switch (sdata->vif.type) {
3778 	case NL80211_IFTYPE_STATION:
3779 		if (!bssid && !sdata->u.mgd.use_4addr)
3780 			return false;
3781 		if (multicast)
3782 			return true;
3783 		return ether_addr_equal(sdata->vif.addr, hdr->addr1);
3784 	case NL80211_IFTYPE_ADHOC:
3785 		if (!bssid)
3786 			return false;
3787 		if (ether_addr_equal(sdata->vif.addr, hdr->addr2) ||
3788 		    ether_addr_equal(sdata->u.ibss.bssid, hdr->addr2))
3789 			return false;
3790 		if (ieee80211_is_beacon(hdr->frame_control))
3791 			return true;
3792 		if (!ieee80211_bssid_match(bssid, sdata->u.ibss.bssid))
3793 			return false;
3794 		if (!multicast &&
3795 		    !ether_addr_equal(sdata->vif.addr, hdr->addr1))
3796 			return false;
3797 		if (!rx->sta) {
3798 			int rate_idx;
3799 			if (status->encoding != RX_ENC_LEGACY)
3800 				rate_idx = 0; /* TODO: HT/VHT rates */
3801 			else
3802 				rate_idx = status->rate_idx;
3803 			ieee80211_ibss_rx_no_sta(sdata, bssid, hdr->addr2,
3804 						 BIT(rate_idx));
3805 		}
3806 		return true;
3807 	case NL80211_IFTYPE_OCB:
3808 		if (!bssid)
3809 			return false;
3810 		if (!ieee80211_is_data_present(hdr->frame_control))
3811 			return false;
3812 		if (!is_broadcast_ether_addr(bssid))
3813 			return false;
3814 		if (!multicast &&
3815 		    !ether_addr_equal(sdata->dev->dev_addr, hdr->addr1))
3816 			return false;
3817 		if (!rx->sta) {
3818 			int rate_idx;
3819 			if (status->encoding != RX_ENC_LEGACY)
3820 				rate_idx = 0; /* TODO: HT rates */
3821 			else
3822 				rate_idx = status->rate_idx;
3823 			ieee80211_ocb_rx_no_sta(sdata, bssid, hdr->addr2,
3824 						BIT(rate_idx));
3825 		}
3826 		return true;
3827 	case NL80211_IFTYPE_MESH_POINT:
3828 		if (ether_addr_equal(sdata->vif.addr, hdr->addr2))
3829 			return false;
3830 		if (multicast)
3831 			return true;
3832 		return ether_addr_equal(sdata->vif.addr, hdr->addr1);
3833 	case NL80211_IFTYPE_AP_VLAN:
3834 	case NL80211_IFTYPE_AP:
3835 		if (!bssid)
3836 			return ether_addr_equal(sdata->vif.addr, hdr->addr1);
3837 
3838 		if (!ieee80211_bssid_match(bssid, sdata->vif.addr)) {
3839 			/*
3840 			 * Accept public action frames even when the
3841 			 * BSSID doesn't match, this is used for P2P
3842 			 * and location updates. Note that mac80211
3843 			 * itself never looks at these frames.
3844 			 */
3845 			if (!multicast &&
3846 			    !ether_addr_equal(sdata->vif.addr, hdr->addr1))
3847 				return false;
3848 			if (ieee80211_is_public_action(hdr, skb->len))
3849 				return true;
3850 			return ieee80211_is_beacon(hdr->frame_control);
3851 		}
3852 
3853 		if (!ieee80211_has_tods(hdr->frame_control)) {
3854 			/* ignore data frames to TDLS-peers */
3855 			if (ieee80211_is_data(hdr->frame_control))
3856 				return false;
3857 			/* ignore action frames to TDLS-peers */
3858 			if (ieee80211_is_action(hdr->frame_control) &&
3859 			    !is_broadcast_ether_addr(bssid) &&
3860 			    !ether_addr_equal(bssid, hdr->addr1))
3861 				return false;
3862 		}
3863 
3864 		/*
3865 		 * 802.11-2016 Table 9-26 says that for data frames, A1 must be
3866 		 * the BSSID - we've checked that already but may have accepted
3867 		 * the wildcard (ff:ff:ff:ff:ff:ff).
3868 		 *
3869 		 * It also says:
3870 		 *	The BSSID of the Data frame is determined as follows:
3871 		 *	a) If the STA is contained within an AP or is associated
3872 		 *	   with an AP, the BSSID is the address currently in use
3873 		 *	   by the STA contained in the AP.
3874 		 *
3875 		 * So we should not accept data frames with an address that's
3876 		 * multicast.
3877 		 *
3878 		 * Accepting it also opens a security problem because stations
3879 		 * could encrypt it with the GTK and inject traffic that way.
3880 		 */
3881 		if (ieee80211_is_data(hdr->frame_control) && multicast)
3882 			return false;
3883 
3884 		return true;
3885 	case NL80211_IFTYPE_WDS:
3886 		if (bssid || !ieee80211_is_data(hdr->frame_control))
3887 			return false;
3888 		return ether_addr_equal(sdata->u.wds.remote_addr, hdr->addr2);
3889 	case NL80211_IFTYPE_P2P_DEVICE:
3890 		return ieee80211_is_public_action(hdr, skb->len) ||
3891 		       ieee80211_is_probe_req(hdr->frame_control) ||
3892 		       ieee80211_is_probe_resp(hdr->frame_control) ||
3893 		       ieee80211_is_beacon(hdr->frame_control);
3894 	case NL80211_IFTYPE_NAN:
3895 		/* Currently no frames on NAN interface are allowed */
3896 		return false;
3897 	default:
3898 		break;
3899 	}
3900 
3901 	WARN_ON_ONCE(1);
3902 	return false;
3903 }
3904 
3905 void ieee80211_check_fast_rx(struct sta_info *sta)
3906 {
3907 	struct ieee80211_sub_if_data *sdata = sta->sdata;
3908 	struct ieee80211_local *local = sdata->local;
3909 	struct ieee80211_key *key;
3910 	struct ieee80211_fast_rx fastrx = {
3911 		.dev = sdata->dev,
3912 		.vif_type = sdata->vif.type,
3913 		.control_port_protocol = sdata->control_port_protocol,
3914 	}, *old, *new = NULL;
3915 	bool assign = false;
3916 
3917 	/* use sparse to check that we don't return without updating */
3918 	__acquire(check_fast_rx);
3919 
3920 	BUILD_BUG_ON(sizeof(fastrx.rfc1042_hdr) != sizeof(rfc1042_header));
3921 	BUILD_BUG_ON(sizeof(fastrx.rfc1042_hdr) != ETH_ALEN);
3922 	ether_addr_copy(fastrx.rfc1042_hdr, rfc1042_header);
3923 	ether_addr_copy(fastrx.vif_addr, sdata->vif.addr);
3924 
3925 	fastrx.uses_rss = ieee80211_hw_check(&local->hw, USES_RSS);
3926 
3927 	/* fast-rx doesn't do reordering */
3928 	if (ieee80211_hw_check(&local->hw, AMPDU_AGGREGATION) &&
3929 	    !ieee80211_hw_check(&local->hw, SUPPORTS_REORDERING_BUFFER))
3930 		goto clear;
3931 
3932 	switch (sdata->vif.type) {
3933 	case NL80211_IFTYPE_STATION:
3934 		if (sta->sta.tdls) {
3935 			fastrx.da_offs = offsetof(struct ieee80211_hdr, addr1);
3936 			fastrx.sa_offs = offsetof(struct ieee80211_hdr, addr2);
3937 			fastrx.expected_ds_bits = 0;
3938 		} else {
3939 			fastrx.sta_notify = sdata->u.mgd.probe_send_count > 0;
3940 			fastrx.da_offs = offsetof(struct ieee80211_hdr, addr1);
3941 			fastrx.sa_offs = offsetof(struct ieee80211_hdr, addr3);
3942 			fastrx.expected_ds_bits =
3943 				cpu_to_le16(IEEE80211_FCTL_FROMDS);
3944 		}
3945 
3946 		if (sdata->u.mgd.use_4addr && !sta->sta.tdls) {
3947 			fastrx.expected_ds_bits |=
3948 				cpu_to_le16(IEEE80211_FCTL_TODS);
3949 			fastrx.da_offs = offsetof(struct ieee80211_hdr, addr3);
3950 			fastrx.sa_offs = offsetof(struct ieee80211_hdr, addr4);
3951 		}
3952 
3953 		if (!sdata->u.mgd.powersave)
3954 			break;
3955 
3956 		/* software powersave is a huge mess, avoid all of it */
3957 		if (ieee80211_hw_check(&local->hw, PS_NULLFUNC_STACK))
3958 			goto clear;
3959 		if (ieee80211_hw_check(&local->hw, SUPPORTS_PS) &&
3960 		    !ieee80211_hw_check(&local->hw, SUPPORTS_DYNAMIC_PS))
3961 			goto clear;
3962 		break;
3963 	case NL80211_IFTYPE_AP_VLAN:
3964 	case NL80211_IFTYPE_AP:
3965 		/* parallel-rx requires this, at least with calls to
3966 		 * ieee80211_sta_ps_transition()
3967 		 */
3968 		if (!ieee80211_hw_check(&local->hw, AP_LINK_PS))
3969 			goto clear;
3970 		fastrx.da_offs = offsetof(struct ieee80211_hdr, addr3);
3971 		fastrx.sa_offs = offsetof(struct ieee80211_hdr, addr2);
3972 		fastrx.expected_ds_bits = cpu_to_le16(IEEE80211_FCTL_TODS);
3973 
3974 		fastrx.internal_forward =
3975 			!(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) &&
3976 			(sdata->vif.type != NL80211_IFTYPE_AP_VLAN ||
3977 			 !sdata->u.vlan.sta);
3978 
3979 		if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
3980 		    sdata->u.vlan.sta) {
3981 			fastrx.expected_ds_bits |=
3982 				cpu_to_le16(IEEE80211_FCTL_FROMDS);
3983 			fastrx.sa_offs = offsetof(struct ieee80211_hdr, addr4);
3984 			fastrx.internal_forward = 0;
3985 		}
3986 
3987 		break;
3988 	default:
3989 		goto clear;
3990 	}
3991 
3992 	if (!test_sta_flag(sta, WLAN_STA_AUTHORIZED))
3993 		goto clear;
3994 
3995 	rcu_read_lock();
3996 	key = rcu_dereference(sta->ptk[sta->ptk_idx]);
3997 	if (key) {
3998 		switch (key->conf.cipher) {
3999 		case WLAN_CIPHER_SUITE_TKIP:
4000 			/* we don't want to deal with MMIC in fast-rx */
4001 			goto clear_rcu;
4002 		case WLAN_CIPHER_SUITE_CCMP:
4003 		case WLAN_CIPHER_SUITE_CCMP_256:
4004 		case WLAN_CIPHER_SUITE_GCMP:
4005 		case WLAN_CIPHER_SUITE_GCMP_256:
4006 			break;
4007 		default:
4008 			/* we also don't want to deal with WEP or cipher scheme
4009 			 * since those require looking up the key idx in the
4010 			 * frame, rather than assuming the PTK is used
4011 			 * (we need to revisit this once we implement the real
4012 			 * PTK index, which is now valid in the spec, but we
4013 			 * haven't implemented that part yet)
4014 			 */
4015 			goto clear_rcu;
4016 		}
4017 
4018 		fastrx.key = true;
4019 		fastrx.icv_len = key->conf.icv_len;
4020 	}
4021 
4022 	assign = true;
4023  clear_rcu:
4024 	rcu_read_unlock();
4025  clear:
4026 	__release(check_fast_rx);
4027 
4028 	if (assign)
4029 		new = kmemdup(&fastrx, sizeof(fastrx), GFP_KERNEL);
4030 
4031 	spin_lock_bh(&sta->lock);
4032 	old = rcu_dereference_protected(sta->fast_rx, true);
4033 	rcu_assign_pointer(sta->fast_rx, new);
4034 	spin_unlock_bh(&sta->lock);
4035 
4036 	if (old)
4037 		kfree_rcu(old, rcu_head);
4038 }
4039 
4040 void ieee80211_clear_fast_rx(struct sta_info *sta)
4041 {
4042 	struct ieee80211_fast_rx *old;
4043 
4044 	spin_lock_bh(&sta->lock);
4045 	old = rcu_dereference_protected(sta->fast_rx, true);
4046 	RCU_INIT_POINTER(sta->fast_rx, NULL);
4047 	spin_unlock_bh(&sta->lock);
4048 
4049 	if (old)
4050 		kfree_rcu(old, rcu_head);
4051 }
4052 
4053 void __ieee80211_check_fast_rx_iface(struct ieee80211_sub_if_data *sdata)
4054 {
4055 	struct ieee80211_local *local = sdata->local;
4056 	struct sta_info *sta;
4057 
4058 	lockdep_assert_held(&local->sta_mtx);
4059 
4060 	list_for_each_entry_rcu(sta, &local->sta_list, list) {
4061 		if (sdata != sta->sdata &&
4062 		    (!sta->sdata->bss || sta->sdata->bss != sdata->bss))
4063 			continue;
4064 		ieee80211_check_fast_rx(sta);
4065 	}
4066 }
4067 
4068 void ieee80211_check_fast_rx_iface(struct ieee80211_sub_if_data *sdata)
4069 {
4070 	struct ieee80211_local *local = sdata->local;
4071 
4072 	mutex_lock(&local->sta_mtx);
4073 	__ieee80211_check_fast_rx_iface(sdata);
4074 	mutex_unlock(&local->sta_mtx);
4075 }
4076 
4077 static bool ieee80211_invoke_fast_rx(struct ieee80211_rx_data *rx,
4078 				     struct ieee80211_fast_rx *fast_rx)
4079 {
4080 	struct sk_buff *skb = rx->skb;
4081 	struct ieee80211_hdr *hdr = (void *)skb->data;
4082 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
4083 	struct sta_info *sta = rx->sta;
4084 	int orig_len = skb->len;
4085 	int hdrlen = ieee80211_hdrlen(hdr->frame_control);
4086 	int snap_offs = hdrlen;
4087 	struct {
4088 		u8 snap[sizeof(rfc1042_header)];
4089 		__be16 proto;
4090 	} *payload __aligned(2);
4091 	struct {
4092 		u8 da[ETH_ALEN];
4093 		u8 sa[ETH_ALEN];
4094 	} addrs __aligned(2);
4095 	struct ieee80211_sta_rx_stats *stats = &sta->rx_stats;
4096 
4097 	if (fast_rx->uses_rss)
4098 		stats = this_cpu_ptr(sta->pcpu_rx_stats);
4099 
4100 	/* for parallel-rx, we need to have DUP_VALIDATED, otherwise we write
4101 	 * to a common data structure; drivers can implement that per queue
4102 	 * but we don't have that information in mac80211
4103 	 */
4104 	if (!(status->flag & RX_FLAG_DUP_VALIDATED))
4105 		return false;
4106 
4107 #define FAST_RX_CRYPT_FLAGS	(RX_FLAG_PN_VALIDATED | RX_FLAG_DECRYPTED)
4108 
4109 	/* If using encryption, we also need to have:
4110 	 *  - PN_VALIDATED: similar, but the implementation is tricky
4111 	 *  - DECRYPTED: necessary for PN_VALIDATED
4112 	 */
4113 	if (fast_rx->key &&
4114 	    (status->flag & FAST_RX_CRYPT_FLAGS) != FAST_RX_CRYPT_FLAGS)
4115 		return false;
4116 
4117 	if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
4118 		return false;
4119 
4120 	if (unlikely(ieee80211_is_frag(hdr)))
4121 		return false;
4122 
4123 	/* Since our interface address cannot be multicast, this
4124 	 * implicitly also rejects multicast frames without the
4125 	 * explicit check.
4126 	 *
4127 	 * We shouldn't get any *data* frames not addressed to us
4128 	 * (AP mode will accept multicast *management* frames), but
4129 	 * punting here will make it go through the full checks in
4130 	 * ieee80211_accept_frame().
4131 	 */
4132 	if (!ether_addr_equal(fast_rx->vif_addr, hdr->addr1))
4133 		return false;
4134 
4135 	if ((hdr->frame_control & cpu_to_le16(IEEE80211_FCTL_FROMDS |
4136 					      IEEE80211_FCTL_TODS)) !=
4137 	    fast_rx->expected_ds_bits)
4138 		return false;
4139 
4140 	/* assign the key to drop unencrypted frames (later)
4141 	 * and strip the IV/MIC if necessary
4142 	 */
4143 	if (fast_rx->key && !(status->flag & RX_FLAG_IV_STRIPPED)) {
4144 		/* GCMP header length is the same */
4145 		snap_offs += IEEE80211_CCMP_HDR_LEN;
4146 	}
4147 
4148 	if (!(status->rx_flags & IEEE80211_RX_AMSDU)) {
4149 		if (!pskb_may_pull(skb, snap_offs + sizeof(*payload)))
4150 			goto drop;
4151 
4152 		payload = (void *)(skb->data + snap_offs);
4153 
4154 		if (!ether_addr_equal(payload->snap, fast_rx->rfc1042_hdr))
4155 			return false;
4156 
4157 		/* Don't handle these here since they require special code.
4158 		 * Accept AARP and IPX even though they should come with a
4159 		 * bridge-tunnel header - but if we get them this way then
4160 		 * there's little point in discarding them.
4161 		 */
4162 		if (unlikely(payload->proto == cpu_to_be16(ETH_P_TDLS) ||
4163 			     payload->proto == fast_rx->control_port_protocol))
4164 			return false;
4165 	}
4166 
4167 	/* after this point, don't punt to the slowpath! */
4168 
4169 	if (rx->key && !(status->flag & RX_FLAG_MIC_STRIPPED) &&
4170 	    pskb_trim(skb, skb->len - fast_rx->icv_len))
4171 		goto drop;
4172 
4173 	if (unlikely(fast_rx->sta_notify)) {
4174 		ieee80211_sta_rx_notify(rx->sdata, hdr);
4175 		fast_rx->sta_notify = false;
4176 	}
4177 
4178 	/* statistics part of ieee80211_rx_h_sta_process() */
4179 	if (!(status->flag & RX_FLAG_NO_SIGNAL_VAL)) {
4180 		stats->last_signal = status->signal;
4181 		if (!fast_rx->uses_rss)
4182 			ewma_signal_add(&sta->rx_stats_avg.signal,
4183 					-status->signal);
4184 	}
4185 
4186 	if (status->chains) {
4187 		int i;
4188 
4189 		stats->chains = status->chains;
4190 		for (i = 0; i < ARRAY_SIZE(status->chain_signal); i++) {
4191 			int signal = status->chain_signal[i];
4192 
4193 			if (!(status->chains & BIT(i)))
4194 				continue;
4195 
4196 			stats->chain_signal_last[i] = signal;
4197 			if (!fast_rx->uses_rss)
4198 				ewma_signal_add(&sta->rx_stats_avg.chain_signal[i],
4199 						-signal);
4200 		}
4201 	}
4202 	/* end of statistics */
4203 
4204 	if (rx->key && !ieee80211_has_protected(hdr->frame_control))
4205 		goto drop;
4206 
4207 	if (status->rx_flags & IEEE80211_RX_AMSDU) {
4208 		if (__ieee80211_rx_h_amsdu(rx, snap_offs - hdrlen) !=
4209 		    RX_QUEUED)
4210 			goto drop;
4211 
4212 		return true;
4213 	}
4214 
4215 	stats->last_rx = jiffies;
4216 	stats->last_rate = sta_stats_encode_rate(status);
4217 
4218 	stats->fragments++;
4219 	stats->packets++;
4220 
4221 	/* do the header conversion - first grab the addresses */
4222 	ether_addr_copy(addrs.da, skb->data + fast_rx->da_offs);
4223 	ether_addr_copy(addrs.sa, skb->data + fast_rx->sa_offs);
4224 	/* remove the SNAP but leave the ethertype */
4225 	skb_pull(skb, snap_offs + sizeof(rfc1042_header));
4226 	/* push the addresses in front */
4227 	memcpy(skb_push(skb, sizeof(addrs)), &addrs, sizeof(addrs));
4228 
4229 	skb->dev = fast_rx->dev;
4230 
4231 	ieee80211_rx_stats(fast_rx->dev, skb->len);
4232 
4233 	/* The seqno index has the same property as needed
4234 	 * for the rx_msdu field, i.e. it is IEEE80211_NUM_TIDS
4235 	 * for non-QoS-data frames. Here we know it's a data
4236 	 * frame, so count MSDUs.
4237 	 */
4238 	u64_stats_update_begin(&stats->syncp);
4239 	stats->msdu[rx->seqno_idx]++;
4240 	stats->bytes += orig_len;
4241 	u64_stats_update_end(&stats->syncp);
4242 
4243 	if (fast_rx->internal_forward) {
4244 		struct sk_buff *xmit_skb = NULL;
4245 		if (is_multicast_ether_addr(addrs.da)) {
4246 			xmit_skb = skb_copy(skb, GFP_ATOMIC);
4247 		} else if (!ether_addr_equal(addrs.da, addrs.sa) &&
4248 			   sta_info_get(rx->sdata, addrs.da)) {
4249 			xmit_skb = skb;
4250 			skb = NULL;
4251 		}
4252 
4253 		if (xmit_skb) {
4254 			/*
4255 			 * Send to wireless media and increase priority by 256
4256 			 * to keep the received priority instead of
4257 			 * reclassifying the frame (see cfg80211_classify8021d).
4258 			 */
4259 			xmit_skb->priority += 256;
4260 			xmit_skb->protocol = htons(ETH_P_802_3);
4261 			skb_reset_network_header(xmit_skb);
4262 			skb_reset_mac_header(xmit_skb);
4263 			dev_queue_xmit(xmit_skb);
4264 		}
4265 
4266 		if (!skb)
4267 			return true;
4268 	}
4269 
4270 	/* deliver to local stack */
4271 	skb->protocol = eth_type_trans(skb, fast_rx->dev);
4272 	memset(skb->cb, 0, sizeof(skb->cb));
4273 	if (rx->napi)
4274 		napi_gro_receive(rx->napi, skb);
4275 	else
4276 		netif_receive_skb(skb);
4277 
4278 	return true;
4279  drop:
4280 	dev_kfree_skb(skb);
4281 	stats->dropped++;
4282 	return true;
4283 }
4284 
4285 /*
4286  * This function returns whether or not the SKB
4287  * was destined for RX processing or not, which,
4288  * if consume is true, is equivalent to whether
4289  * or not the skb was consumed.
4290  */
4291 static bool ieee80211_prepare_and_rx_handle(struct ieee80211_rx_data *rx,
4292 					    struct sk_buff *skb, bool consume)
4293 {
4294 	struct ieee80211_local *local = rx->local;
4295 	struct ieee80211_sub_if_data *sdata = rx->sdata;
4296 
4297 	rx->skb = skb;
4298 
4299 	/* See if we can do fast-rx; if we have to copy we already lost,
4300 	 * so punt in that case. We should never have to deliver a data
4301 	 * frame to multiple interfaces anyway.
4302 	 *
4303 	 * We skip the ieee80211_accept_frame() call and do the necessary
4304 	 * checking inside ieee80211_invoke_fast_rx().
4305 	 */
4306 	if (consume && rx->sta) {
4307 		struct ieee80211_fast_rx *fast_rx;
4308 
4309 		fast_rx = rcu_dereference(rx->sta->fast_rx);
4310 		if (fast_rx && ieee80211_invoke_fast_rx(rx, fast_rx))
4311 			return true;
4312 	}
4313 
4314 	if (!ieee80211_accept_frame(rx))
4315 		return false;
4316 
4317 	if (!consume) {
4318 		skb = skb_copy(skb, GFP_ATOMIC);
4319 		if (!skb) {
4320 			if (net_ratelimit())
4321 				wiphy_debug(local->hw.wiphy,
4322 					"failed to copy skb for %s\n",
4323 					sdata->name);
4324 			return true;
4325 		}
4326 
4327 		rx->skb = skb;
4328 	}
4329 
4330 	ieee80211_invoke_rx_handlers(rx);
4331 	return true;
4332 }
4333 
4334 /*
4335  * This is the actual Rx frames handler. as it belongs to Rx path it must
4336  * be called with rcu_read_lock protection.
4337  */
4338 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
4339 					 struct ieee80211_sta *pubsta,
4340 					 struct sk_buff *skb,
4341 					 struct napi_struct *napi)
4342 {
4343 	struct ieee80211_local *local = hw_to_local(hw);
4344 	struct ieee80211_sub_if_data *sdata;
4345 	struct ieee80211_hdr *hdr;
4346 	__le16 fc;
4347 	struct ieee80211_rx_data rx;
4348 	struct ieee80211_sub_if_data *prev;
4349 	struct rhlist_head *tmp;
4350 	int err = 0;
4351 
4352 	fc = ((struct ieee80211_hdr *)skb->data)->frame_control;
4353 	memset(&rx, 0, sizeof(rx));
4354 	rx.skb = skb;
4355 	rx.local = local;
4356 	rx.napi = napi;
4357 
4358 	if (ieee80211_is_data(fc) || ieee80211_is_mgmt(fc))
4359 		I802_DEBUG_INC(local->dot11ReceivedFragmentCount);
4360 
4361 	if (ieee80211_is_mgmt(fc)) {
4362 		/* drop frame if too short for header */
4363 		if (skb->len < ieee80211_hdrlen(fc))
4364 			err = -ENOBUFS;
4365 		else
4366 			err = skb_linearize(skb);
4367 	} else {
4368 		err = !pskb_may_pull(skb, ieee80211_hdrlen(fc));
4369 	}
4370 
4371 	if (err) {
4372 		dev_kfree_skb(skb);
4373 		return;
4374 	}
4375 
4376 	hdr = (struct ieee80211_hdr *)skb->data;
4377 	ieee80211_parse_qos(&rx);
4378 	ieee80211_verify_alignment(&rx);
4379 
4380 	if (unlikely(ieee80211_is_probe_resp(hdr->frame_control) ||
4381 		     ieee80211_is_beacon(hdr->frame_control)))
4382 		ieee80211_scan_rx(local, skb);
4383 
4384 	if (ieee80211_is_data(fc)) {
4385 		struct sta_info *sta, *prev_sta;
4386 
4387 		if (pubsta) {
4388 			rx.sta = container_of(pubsta, struct sta_info, sta);
4389 			rx.sdata = rx.sta->sdata;
4390 			if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
4391 				return;
4392 			goto out;
4393 		}
4394 
4395 		prev_sta = NULL;
4396 
4397 		for_each_sta_info(local, hdr->addr2, sta, tmp) {
4398 			if (!prev_sta) {
4399 				prev_sta = sta;
4400 				continue;
4401 			}
4402 
4403 			rx.sta = prev_sta;
4404 			rx.sdata = prev_sta->sdata;
4405 			ieee80211_prepare_and_rx_handle(&rx, skb, false);
4406 
4407 			prev_sta = sta;
4408 		}
4409 
4410 		if (prev_sta) {
4411 			rx.sta = prev_sta;
4412 			rx.sdata = prev_sta->sdata;
4413 
4414 			if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
4415 				return;
4416 			goto out;
4417 		}
4418 	}
4419 
4420 	prev = NULL;
4421 
4422 	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
4423 		if (!ieee80211_sdata_running(sdata))
4424 			continue;
4425 
4426 		if (sdata->vif.type == NL80211_IFTYPE_MONITOR ||
4427 		    sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
4428 			continue;
4429 
4430 		/*
4431 		 * frame is destined for this interface, but if it's
4432 		 * not also for the previous one we handle that after
4433 		 * the loop to avoid copying the SKB once too much
4434 		 */
4435 
4436 		if (!prev) {
4437 			prev = sdata;
4438 			continue;
4439 		}
4440 
4441 		rx.sta = sta_info_get_bss(prev, hdr->addr2);
4442 		rx.sdata = prev;
4443 		ieee80211_prepare_and_rx_handle(&rx, skb, false);
4444 
4445 		prev = sdata;
4446 	}
4447 
4448 	if (prev) {
4449 		rx.sta = sta_info_get_bss(prev, hdr->addr2);
4450 		rx.sdata = prev;
4451 
4452 		if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
4453 			return;
4454 	}
4455 
4456  out:
4457 	dev_kfree_skb(skb);
4458 }
4459 
4460 /*
4461  * This is the receive path handler. It is called by a low level driver when an
4462  * 802.11 MPDU is received from the hardware.
4463  */
4464 void ieee80211_rx_napi(struct ieee80211_hw *hw, struct ieee80211_sta *pubsta,
4465 		       struct sk_buff *skb, struct napi_struct *napi)
4466 {
4467 	struct ieee80211_local *local = hw_to_local(hw);
4468 	struct ieee80211_rate *rate = NULL;
4469 	struct ieee80211_supported_band *sband;
4470 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
4471 
4472 	WARN_ON_ONCE(softirq_count() == 0);
4473 
4474 	if (WARN_ON(status->band >= NUM_NL80211_BANDS))
4475 		goto drop;
4476 
4477 	sband = local->hw.wiphy->bands[status->band];
4478 	if (WARN_ON(!sband))
4479 		goto drop;
4480 
4481 	/*
4482 	 * If we're suspending, it is possible although not too likely
4483 	 * that we'd be receiving frames after having already partially
4484 	 * quiesced the stack. We can't process such frames then since
4485 	 * that might, for example, cause stations to be added or other
4486 	 * driver callbacks be invoked.
4487 	 */
4488 	if (unlikely(local->quiescing || local->suspended))
4489 		goto drop;
4490 
4491 	/* We might be during a HW reconfig, prevent Rx for the same reason */
4492 	if (unlikely(local->in_reconfig))
4493 		goto drop;
4494 
4495 	/*
4496 	 * The same happens when we're not even started,
4497 	 * but that's worth a warning.
4498 	 */
4499 	if (WARN_ON(!local->started))
4500 		goto drop;
4501 
4502 	if (likely(!(status->flag & RX_FLAG_FAILED_PLCP_CRC))) {
4503 		/*
4504 		 * Validate the rate, unless a PLCP error means that
4505 		 * we probably can't have a valid rate here anyway.
4506 		 */
4507 
4508 		switch (status->encoding) {
4509 		case RX_ENC_HT:
4510 			/*
4511 			 * rate_idx is MCS index, which can be [0-76]
4512 			 * as documented on:
4513 			 *
4514 			 * http://wireless.kernel.org/en/developers/Documentation/ieee80211/802.11n
4515 			 *
4516 			 * Anything else would be some sort of driver or
4517 			 * hardware error. The driver should catch hardware
4518 			 * errors.
4519 			 */
4520 			if (WARN(status->rate_idx > 76,
4521 				 "Rate marked as an HT rate but passed "
4522 				 "status->rate_idx is not "
4523 				 "an MCS index [0-76]: %d (0x%02x)\n",
4524 				 status->rate_idx,
4525 				 status->rate_idx))
4526 				goto drop;
4527 			break;
4528 		case RX_ENC_VHT:
4529 			if (WARN_ONCE(status->rate_idx > 9 ||
4530 				      !status->nss ||
4531 				      status->nss > 8,
4532 				      "Rate marked as a VHT rate but data is invalid: MCS: %d, NSS: %d\n",
4533 				      status->rate_idx, status->nss))
4534 				goto drop;
4535 			break;
4536 		case RX_ENC_HE:
4537 			if (WARN_ONCE(status->rate_idx > 11 ||
4538 				      !status->nss ||
4539 				      status->nss > 8,
4540 				      "Rate marked as an HE rate but data is invalid: MCS: %d, NSS: %d\n",
4541 				      status->rate_idx, status->nss))
4542 				goto drop;
4543 			break;
4544 		default:
4545 			WARN_ON_ONCE(1);
4546 			/* fall through */
4547 		case RX_ENC_LEGACY:
4548 			if (WARN_ON(status->rate_idx >= sband->n_bitrates))
4549 				goto drop;
4550 			rate = &sband->bitrates[status->rate_idx];
4551 		}
4552 	}
4553 
4554 	status->rx_flags = 0;
4555 
4556 	/*
4557 	 * key references and virtual interfaces are protected using RCU
4558 	 * and this requires that we are in a read-side RCU section during
4559 	 * receive processing
4560 	 */
4561 	rcu_read_lock();
4562 
4563 	/*
4564 	 * Frames with failed FCS/PLCP checksum are not returned,
4565 	 * all other frames are returned without radiotap header
4566 	 * if it was previously present.
4567 	 * Also, frames with less than 16 bytes are dropped.
4568 	 */
4569 	skb = ieee80211_rx_monitor(local, skb, rate);
4570 	if (!skb) {
4571 		rcu_read_unlock();
4572 		return;
4573 	}
4574 
4575 	ieee80211_tpt_led_trig_rx(local,
4576 			((struct ieee80211_hdr *)skb->data)->frame_control,
4577 			skb->len);
4578 
4579 	__ieee80211_rx_handle_packet(hw, pubsta, skb, napi);
4580 
4581 	rcu_read_unlock();
4582 
4583 	return;
4584  drop:
4585 	kfree_skb(skb);
4586 }
4587 EXPORT_SYMBOL(ieee80211_rx_napi);
4588 
4589 /* This is a version of the rx handler that can be called from hard irq
4590  * context. Post the skb on the queue and schedule the tasklet */
4591 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb)
4592 {
4593 	struct ieee80211_local *local = hw_to_local(hw);
4594 
4595 	BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
4596 
4597 	skb->pkt_type = IEEE80211_RX_MSG;
4598 	skb_queue_tail(&local->skb_queue, skb);
4599 	tasklet_schedule(&local->tasklet);
4600 }
4601 EXPORT_SYMBOL(ieee80211_rx_irqsafe);
4602