xref: /linux/net/mac80211/rx.c (revision f6f3bac08ff9855d803081a353a1fafaa8845739)
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_qos_nullfunc(hdr->frame_control) ||
1407 	    is_multicast_ether_addr(hdr->addr1))
1408 		return RX_CONTINUE;
1409 
1410 	if (!rx->sta)
1411 		return RX_CONTINUE;
1412 
1413 	if (unlikely(ieee80211_has_retry(hdr->frame_control) &&
1414 		     rx->sta->last_seq_ctrl[rx->seqno_idx] == hdr->seq_ctrl)) {
1415 		I802_DEBUG_INC(rx->local->dot11FrameDuplicateCount);
1416 		rx->sta->rx_stats.num_duplicates++;
1417 		return RX_DROP_UNUSABLE;
1418 	} else if (!(status->flag & RX_FLAG_AMSDU_MORE)) {
1419 		rx->sta->last_seq_ctrl[rx->seqno_idx] = hdr->seq_ctrl;
1420 	}
1421 
1422 	return RX_CONTINUE;
1423 }
1424 
1425 static ieee80211_rx_result debug_noinline
1426 ieee80211_rx_h_check(struct ieee80211_rx_data *rx)
1427 {
1428 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1429 
1430 	/* Drop disallowed frame classes based on STA auth/assoc state;
1431 	 * IEEE 802.11, Chap 5.5.
1432 	 *
1433 	 * mac80211 filters only based on association state, i.e. it drops
1434 	 * Class 3 frames from not associated stations. hostapd sends
1435 	 * deauth/disassoc frames when needed. In addition, hostapd is
1436 	 * responsible for filtering on both auth and assoc states.
1437 	 */
1438 
1439 	if (ieee80211_vif_is_mesh(&rx->sdata->vif))
1440 		return ieee80211_rx_mesh_check(rx);
1441 
1442 	if (unlikely((ieee80211_is_data(hdr->frame_control) ||
1443 		      ieee80211_is_pspoll(hdr->frame_control)) &&
1444 		     rx->sdata->vif.type != NL80211_IFTYPE_ADHOC &&
1445 		     rx->sdata->vif.type != NL80211_IFTYPE_WDS &&
1446 		     rx->sdata->vif.type != NL80211_IFTYPE_OCB &&
1447 		     (!rx->sta || !test_sta_flag(rx->sta, WLAN_STA_ASSOC)))) {
1448 		/*
1449 		 * accept port control frames from the AP even when it's not
1450 		 * yet marked ASSOC to prevent a race where we don't set the
1451 		 * assoc bit quickly enough before it sends the first frame
1452 		 */
1453 		if (rx->sta && rx->sdata->vif.type == NL80211_IFTYPE_STATION &&
1454 		    ieee80211_is_data_present(hdr->frame_control)) {
1455 			unsigned int hdrlen;
1456 			__be16 ethertype;
1457 
1458 			hdrlen = ieee80211_hdrlen(hdr->frame_control);
1459 
1460 			if (rx->skb->len < hdrlen + 8)
1461 				return RX_DROP_MONITOR;
1462 
1463 			skb_copy_bits(rx->skb, hdrlen + 6, &ethertype, 2);
1464 			if (ethertype == rx->sdata->control_port_protocol)
1465 				return RX_CONTINUE;
1466 		}
1467 
1468 		if (rx->sdata->vif.type == NL80211_IFTYPE_AP &&
1469 		    cfg80211_rx_spurious_frame(rx->sdata->dev,
1470 					       hdr->addr2,
1471 					       GFP_ATOMIC))
1472 			return RX_DROP_UNUSABLE;
1473 
1474 		return RX_DROP_MONITOR;
1475 	}
1476 
1477 	return RX_CONTINUE;
1478 }
1479 
1480 
1481 static ieee80211_rx_result debug_noinline
1482 ieee80211_rx_h_check_more_data(struct ieee80211_rx_data *rx)
1483 {
1484 	struct ieee80211_local *local;
1485 	struct ieee80211_hdr *hdr;
1486 	struct sk_buff *skb;
1487 
1488 	local = rx->local;
1489 	skb = rx->skb;
1490 	hdr = (struct ieee80211_hdr *) skb->data;
1491 
1492 	if (!local->pspolling)
1493 		return RX_CONTINUE;
1494 
1495 	if (!ieee80211_has_fromds(hdr->frame_control))
1496 		/* this is not from AP */
1497 		return RX_CONTINUE;
1498 
1499 	if (!ieee80211_is_data(hdr->frame_control))
1500 		return RX_CONTINUE;
1501 
1502 	if (!ieee80211_has_moredata(hdr->frame_control)) {
1503 		/* AP has no more frames buffered for us */
1504 		local->pspolling = false;
1505 		return RX_CONTINUE;
1506 	}
1507 
1508 	/* more data bit is set, let's request a new frame from the AP */
1509 	ieee80211_send_pspoll(local, rx->sdata);
1510 
1511 	return RX_CONTINUE;
1512 }
1513 
1514 static void sta_ps_start(struct sta_info *sta)
1515 {
1516 	struct ieee80211_sub_if_data *sdata = sta->sdata;
1517 	struct ieee80211_local *local = sdata->local;
1518 	struct ps_data *ps;
1519 	int tid;
1520 
1521 	if (sta->sdata->vif.type == NL80211_IFTYPE_AP ||
1522 	    sta->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
1523 		ps = &sdata->bss->ps;
1524 	else
1525 		return;
1526 
1527 	atomic_inc(&ps->num_sta_ps);
1528 	set_sta_flag(sta, WLAN_STA_PS_STA);
1529 	if (!ieee80211_hw_check(&local->hw, AP_LINK_PS))
1530 		drv_sta_notify(local, sdata, STA_NOTIFY_SLEEP, &sta->sta);
1531 	ps_dbg(sdata, "STA %pM aid %d enters power save mode\n",
1532 	       sta->sta.addr, sta->sta.aid);
1533 
1534 	ieee80211_clear_fast_xmit(sta);
1535 
1536 	if (!sta->sta.txq[0])
1537 		return;
1538 
1539 	for (tid = 0; tid < IEEE80211_NUM_TIDS; tid++) {
1540 		if (txq_has_queue(sta->sta.txq[tid]))
1541 			set_bit(tid, &sta->txq_buffered_tids);
1542 		else
1543 			clear_bit(tid, &sta->txq_buffered_tids);
1544 	}
1545 }
1546 
1547 static void sta_ps_end(struct sta_info *sta)
1548 {
1549 	ps_dbg(sta->sdata, "STA %pM aid %d exits power save mode\n",
1550 	       sta->sta.addr, sta->sta.aid);
1551 
1552 	if (test_sta_flag(sta, WLAN_STA_PS_DRIVER)) {
1553 		/*
1554 		 * Clear the flag only if the other one is still set
1555 		 * so that the TX path won't start TX'ing new frames
1556 		 * directly ... In the case that the driver flag isn't
1557 		 * set ieee80211_sta_ps_deliver_wakeup() will clear it.
1558 		 */
1559 		clear_sta_flag(sta, WLAN_STA_PS_STA);
1560 		ps_dbg(sta->sdata, "STA %pM aid %d driver-ps-blocked\n",
1561 		       sta->sta.addr, sta->sta.aid);
1562 		return;
1563 	}
1564 
1565 	set_sta_flag(sta, WLAN_STA_PS_DELIVER);
1566 	clear_sta_flag(sta, WLAN_STA_PS_STA);
1567 	ieee80211_sta_ps_deliver_wakeup(sta);
1568 }
1569 
1570 int ieee80211_sta_ps_transition(struct ieee80211_sta *pubsta, bool start)
1571 {
1572 	struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
1573 	bool in_ps;
1574 
1575 	WARN_ON(!ieee80211_hw_check(&sta->local->hw, AP_LINK_PS));
1576 
1577 	/* Don't let the same PS state be set twice */
1578 	in_ps = test_sta_flag(sta, WLAN_STA_PS_STA);
1579 	if ((start && in_ps) || (!start && !in_ps))
1580 		return -EINVAL;
1581 
1582 	if (start)
1583 		sta_ps_start(sta);
1584 	else
1585 		sta_ps_end(sta);
1586 
1587 	return 0;
1588 }
1589 EXPORT_SYMBOL(ieee80211_sta_ps_transition);
1590 
1591 void ieee80211_sta_pspoll(struct ieee80211_sta *pubsta)
1592 {
1593 	struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
1594 
1595 	if (test_sta_flag(sta, WLAN_STA_SP))
1596 		return;
1597 
1598 	if (!test_sta_flag(sta, WLAN_STA_PS_DRIVER))
1599 		ieee80211_sta_ps_deliver_poll_response(sta);
1600 	else
1601 		set_sta_flag(sta, WLAN_STA_PSPOLL);
1602 }
1603 EXPORT_SYMBOL(ieee80211_sta_pspoll);
1604 
1605 void ieee80211_sta_uapsd_trigger(struct ieee80211_sta *pubsta, u8 tid)
1606 {
1607 	struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
1608 	int ac = ieee80211_ac_from_tid(tid);
1609 
1610 	/*
1611 	 * If this AC is not trigger-enabled do nothing unless the
1612 	 * driver is calling us after it already checked.
1613 	 *
1614 	 * NB: This could/should check a separate bitmap of trigger-
1615 	 * enabled queues, but for now we only implement uAPSD w/o
1616 	 * TSPEC changes to the ACs, so they're always the same.
1617 	 */
1618 	if (!(sta->sta.uapsd_queues & ieee80211_ac_to_qos_mask[ac]) &&
1619 	    tid != IEEE80211_NUM_TIDS)
1620 		return;
1621 
1622 	/* if we are in a service period, do nothing */
1623 	if (test_sta_flag(sta, WLAN_STA_SP))
1624 		return;
1625 
1626 	if (!test_sta_flag(sta, WLAN_STA_PS_DRIVER))
1627 		ieee80211_sta_ps_deliver_uapsd(sta);
1628 	else
1629 		set_sta_flag(sta, WLAN_STA_UAPSD);
1630 }
1631 EXPORT_SYMBOL(ieee80211_sta_uapsd_trigger);
1632 
1633 static ieee80211_rx_result debug_noinline
1634 ieee80211_rx_h_uapsd_and_pspoll(struct ieee80211_rx_data *rx)
1635 {
1636 	struct ieee80211_sub_if_data *sdata = rx->sdata;
1637 	struct ieee80211_hdr *hdr = (void *)rx->skb->data;
1638 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1639 
1640 	if (!rx->sta)
1641 		return RX_CONTINUE;
1642 
1643 	if (sdata->vif.type != NL80211_IFTYPE_AP &&
1644 	    sdata->vif.type != NL80211_IFTYPE_AP_VLAN)
1645 		return RX_CONTINUE;
1646 
1647 	/*
1648 	 * The device handles station powersave, so don't do anything about
1649 	 * uAPSD and PS-Poll frames (the latter shouldn't even come up from
1650 	 * it to mac80211 since they're handled.)
1651 	 */
1652 	if (ieee80211_hw_check(&sdata->local->hw, AP_LINK_PS))
1653 		return RX_CONTINUE;
1654 
1655 	/*
1656 	 * Don't do anything if the station isn't already asleep. In
1657 	 * the uAPSD case, the station will probably be marked asleep,
1658 	 * in the PS-Poll case the station must be confused ...
1659 	 */
1660 	if (!test_sta_flag(rx->sta, WLAN_STA_PS_STA))
1661 		return RX_CONTINUE;
1662 
1663 	if (unlikely(ieee80211_is_pspoll(hdr->frame_control))) {
1664 		ieee80211_sta_pspoll(&rx->sta->sta);
1665 
1666 		/* Free PS Poll skb here instead of returning RX_DROP that would
1667 		 * count as an dropped frame. */
1668 		dev_kfree_skb(rx->skb);
1669 
1670 		return RX_QUEUED;
1671 	} else if (!ieee80211_has_morefrags(hdr->frame_control) &&
1672 		   !(status->rx_flags & IEEE80211_RX_DEFERRED_RELEASE) &&
1673 		   ieee80211_has_pm(hdr->frame_control) &&
1674 		   (ieee80211_is_data_qos(hdr->frame_control) ||
1675 		    ieee80211_is_qos_nullfunc(hdr->frame_control))) {
1676 		u8 tid = ieee80211_get_tid(hdr);
1677 
1678 		ieee80211_sta_uapsd_trigger(&rx->sta->sta, tid);
1679 	}
1680 
1681 	return RX_CONTINUE;
1682 }
1683 
1684 static ieee80211_rx_result debug_noinline
1685 ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx)
1686 {
1687 	struct sta_info *sta = rx->sta;
1688 	struct sk_buff *skb = rx->skb;
1689 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1690 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1691 	int i;
1692 
1693 	if (!sta)
1694 		return RX_CONTINUE;
1695 
1696 	/*
1697 	 * Update last_rx only for IBSS packets which are for the current
1698 	 * BSSID and for station already AUTHORIZED to avoid keeping the
1699 	 * current IBSS network alive in cases where other STAs start
1700 	 * using different BSSID. This will also give the station another
1701 	 * chance to restart the authentication/authorization in case
1702 	 * something went wrong the first time.
1703 	 */
1704 	if (rx->sdata->vif.type == NL80211_IFTYPE_ADHOC) {
1705 		u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len,
1706 						NL80211_IFTYPE_ADHOC);
1707 		if (ether_addr_equal(bssid, rx->sdata->u.ibss.bssid) &&
1708 		    test_sta_flag(sta, WLAN_STA_AUTHORIZED)) {
1709 			sta->rx_stats.last_rx = jiffies;
1710 			if (ieee80211_is_data(hdr->frame_control) &&
1711 			    !is_multicast_ether_addr(hdr->addr1))
1712 				sta->rx_stats.last_rate =
1713 					sta_stats_encode_rate(status);
1714 		}
1715 	} else if (rx->sdata->vif.type == NL80211_IFTYPE_OCB) {
1716 		sta->rx_stats.last_rx = jiffies;
1717 	} else if (!is_multicast_ether_addr(hdr->addr1)) {
1718 		/*
1719 		 * Mesh beacons will update last_rx when if they are found to
1720 		 * match the current local configuration when processed.
1721 		 */
1722 		sta->rx_stats.last_rx = jiffies;
1723 		if (ieee80211_is_data(hdr->frame_control))
1724 			sta->rx_stats.last_rate = sta_stats_encode_rate(status);
1725 	}
1726 
1727 	if (rx->sdata->vif.type == NL80211_IFTYPE_STATION)
1728 		ieee80211_sta_rx_notify(rx->sdata, hdr);
1729 
1730 	sta->rx_stats.fragments++;
1731 
1732 	u64_stats_update_begin(&rx->sta->rx_stats.syncp);
1733 	sta->rx_stats.bytes += rx->skb->len;
1734 	u64_stats_update_end(&rx->sta->rx_stats.syncp);
1735 
1736 	if (!(status->flag & RX_FLAG_NO_SIGNAL_VAL)) {
1737 		sta->rx_stats.last_signal = status->signal;
1738 		ewma_signal_add(&sta->rx_stats_avg.signal, -status->signal);
1739 	}
1740 
1741 	if (status->chains) {
1742 		sta->rx_stats.chains = status->chains;
1743 		for (i = 0; i < ARRAY_SIZE(status->chain_signal); i++) {
1744 			int signal = status->chain_signal[i];
1745 
1746 			if (!(status->chains & BIT(i)))
1747 				continue;
1748 
1749 			sta->rx_stats.chain_signal_last[i] = signal;
1750 			ewma_signal_add(&sta->rx_stats_avg.chain_signal[i],
1751 					-signal);
1752 		}
1753 	}
1754 
1755 	/*
1756 	 * Change STA power saving mode only at the end of a frame
1757 	 * exchange sequence, and only for a data or management
1758 	 * frame as specified in IEEE 802.11-2016 11.2.3.2
1759 	 */
1760 	if (!ieee80211_hw_check(&sta->local->hw, AP_LINK_PS) &&
1761 	    !ieee80211_has_morefrags(hdr->frame_control) &&
1762 	    !is_multicast_ether_addr(hdr->addr1) &&
1763 	    (ieee80211_is_mgmt(hdr->frame_control) ||
1764 	     ieee80211_is_data(hdr->frame_control)) &&
1765 	    !(status->rx_flags & IEEE80211_RX_DEFERRED_RELEASE) &&
1766 	    (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1767 	     rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)) {
1768 		if (test_sta_flag(sta, WLAN_STA_PS_STA)) {
1769 			if (!ieee80211_has_pm(hdr->frame_control))
1770 				sta_ps_end(sta);
1771 		} else {
1772 			if (ieee80211_has_pm(hdr->frame_control))
1773 				sta_ps_start(sta);
1774 		}
1775 	}
1776 
1777 	/* mesh power save support */
1778 	if (ieee80211_vif_is_mesh(&rx->sdata->vif))
1779 		ieee80211_mps_rx_h_sta_process(sta, hdr);
1780 
1781 	/*
1782 	 * Drop (qos-)data::nullfunc frames silently, since they
1783 	 * are used only to control station power saving mode.
1784 	 */
1785 	if (ieee80211_is_nullfunc(hdr->frame_control) ||
1786 	    ieee80211_is_qos_nullfunc(hdr->frame_control)) {
1787 		I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
1788 
1789 		/*
1790 		 * If we receive a 4-addr nullfunc frame from a STA
1791 		 * that was not moved to a 4-addr STA vlan yet send
1792 		 * the event to userspace and for older hostapd drop
1793 		 * the frame to the monitor interface.
1794 		 */
1795 		if (ieee80211_has_a4(hdr->frame_control) &&
1796 		    (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1797 		     (rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1798 		      !rx->sdata->u.vlan.sta))) {
1799 			if (!test_and_set_sta_flag(sta, WLAN_STA_4ADDR_EVENT))
1800 				cfg80211_rx_unexpected_4addr_frame(
1801 					rx->sdata->dev, sta->sta.addr,
1802 					GFP_ATOMIC);
1803 			return RX_DROP_MONITOR;
1804 		}
1805 		/*
1806 		 * Update counter and free packet here to avoid
1807 		 * counting this as a dropped packed.
1808 		 */
1809 		sta->rx_stats.packets++;
1810 		dev_kfree_skb(rx->skb);
1811 		return RX_QUEUED;
1812 	}
1813 
1814 	return RX_CONTINUE;
1815 } /* ieee80211_rx_h_sta_process */
1816 
1817 static ieee80211_rx_result debug_noinline
1818 ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
1819 {
1820 	struct sk_buff *skb = rx->skb;
1821 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1822 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1823 	int keyidx;
1824 	int hdrlen;
1825 	ieee80211_rx_result result = RX_DROP_UNUSABLE;
1826 	struct ieee80211_key *sta_ptk = NULL;
1827 	int mmie_keyidx = -1;
1828 	__le16 fc;
1829 	const struct ieee80211_cipher_scheme *cs = NULL;
1830 
1831 	/*
1832 	 * Key selection 101
1833 	 *
1834 	 * There are four types of keys:
1835 	 *  - GTK (group keys)
1836 	 *  - IGTK (group keys for management frames)
1837 	 *  - PTK (pairwise keys)
1838 	 *  - STK (station-to-station pairwise keys)
1839 	 *
1840 	 * When selecting a key, we have to distinguish between multicast
1841 	 * (including broadcast) and unicast frames, the latter can only
1842 	 * use PTKs and STKs while the former always use GTKs and IGTKs.
1843 	 * Unless, of course, actual WEP keys ("pre-RSNA") are used, then
1844 	 * unicast frames can also use key indices like GTKs. Hence, if we
1845 	 * don't have a PTK/STK we check the key index for a WEP key.
1846 	 *
1847 	 * Note that in a regular BSS, multicast frames are sent by the
1848 	 * AP only, associated stations unicast the frame to the AP first
1849 	 * which then multicasts it on their behalf.
1850 	 *
1851 	 * There is also a slight problem in IBSS mode: GTKs are negotiated
1852 	 * with each station, that is something we don't currently handle.
1853 	 * The spec seems to expect that one negotiates the same key with
1854 	 * every station but there's no such requirement; VLANs could be
1855 	 * possible.
1856 	 */
1857 
1858 	/* start without a key */
1859 	rx->key = NULL;
1860 	fc = hdr->frame_control;
1861 
1862 	if (rx->sta) {
1863 		int keyid = rx->sta->ptk_idx;
1864 
1865 		if (ieee80211_has_protected(fc) && rx->sta->cipher_scheme) {
1866 			cs = rx->sta->cipher_scheme;
1867 			keyid = ieee80211_get_cs_keyid(cs, rx->skb);
1868 			if (unlikely(keyid < 0))
1869 				return RX_DROP_UNUSABLE;
1870 		}
1871 		sta_ptk = rcu_dereference(rx->sta->ptk[keyid]);
1872 	}
1873 
1874 	if (!ieee80211_has_protected(fc))
1875 		mmie_keyidx = ieee80211_get_mmie_keyidx(rx->skb);
1876 
1877 	if (!is_multicast_ether_addr(hdr->addr1) && sta_ptk) {
1878 		rx->key = sta_ptk;
1879 		if ((status->flag & RX_FLAG_DECRYPTED) &&
1880 		    (status->flag & RX_FLAG_IV_STRIPPED))
1881 			return RX_CONTINUE;
1882 		/* Skip decryption if the frame is not protected. */
1883 		if (!ieee80211_has_protected(fc))
1884 			return RX_CONTINUE;
1885 	} else if (mmie_keyidx >= 0) {
1886 		/* Broadcast/multicast robust management frame / BIP */
1887 		if ((status->flag & RX_FLAG_DECRYPTED) &&
1888 		    (status->flag & RX_FLAG_IV_STRIPPED))
1889 			return RX_CONTINUE;
1890 
1891 		if (mmie_keyidx < NUM_DEFAULT_KEYS ||
1892 		    mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
1893 			return RX_DROP_MONITOR; /* unexpected BIP keyidx */
1894 		if (rx->sta) {
1895 			if (ieee80211_is_group_privacy_action(skb) &&
1896 			    test_sta_flag(rx->sta, WLAN_STA_MFP))
1897 				return RX_DROP_MONITOR;
1898 
1899 			rx->key = rcu_dereference(rx->sta->gtk[mmie_keyidx]);
1900 		}
1901 		if (!rx->key)
1902 			rx->key = rcu_dereference(rx->sdata->keys[mmie_keyidx]);
1903 	} else if (!ieee80211_has_protected(fc)) {
1904 		/*
1905 		 * The frame was not protected, so skip decryption. However, we
1906 		 * need to set rx->key if there is a key that could have been
1907 		 * used so that the frame may be dropped if encryption would
1908 		 * have been expected.
1909 		 */
1910 		struct ieee80211_key *key = NULL;
1911 		struct ieee80211_sub_if_data *sdata = rx->sdata;
1912 		int i;
1913 
1914 		if (ieee80211_is_mgmt(fc) &&
1915 		    is_multicast_ether_addr(hdr->addr1) &&
1916 		    (key = rcu_dereference(rx->sdata->default_mgmt_key)))
1917 			rx->key = key;
1918 		else {
1919 			if (rx->sta) {
1920 				for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
1921 					key = rcu_dereference(rx->sta->gtk[i]);
1922 					if (key)
1923 						break;
1924 				}
1925 			}
1926 			if (!key) {
1927 				for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
1928 					key = rcu_dereference(sdata->keys[i]);
1929 					if (key)
1930 						break;
1931 				}
1932 			}
1933 			if (key)
1934 				rx->key = key;
1935 		}
1936 		return RX_CONTINUE;
1937 	} else {
1938 		u8 keyid;
1939 
1940 		/*
1941 		 * The device doesn't give us the IV so we won't be
1942 		 * able to look up the key. That's ok though, we
1943 		 * don't need to decrypt the frame, we just won't
1944 		 * be able to keep statistics accurate.
1945 		 * Except for key threshold notifications, should
1946 		 * we somehow allow the driver to tell us which key
1947 		 * the hardware used if this flag is set?
1948 		 */
1949 		if ((status->flag & RX_FLAG_DECRYPTED) &&
1950 		    (status->flag & RX_FLAG_IV_STRIPPED))
1951 			return RX_CONTINUE;
1952 
1953 		hdrlen = ieee80211_hdrlen(fc);
1954 
1955 		if (cs) {
1956 			keyidx = ieee80211_get_cs_keyid(cs, rx->skb);
1957 
1958 			if (unlikely(keyidx < 0))
1959 				return RX_DROP_UNUSABLE;
1960 		} else {
1961 			if (rx->skb->len < 8 + hdrlen)
1962 				return RX_DROP_UNUSABLE; /* TODO: count this? */
1963 			/*
1964 			 * no need to call ieee80211_wep_get_keyidx,
1965 			 * it verifies a bunch of things we've done already
1966 			 */
1967 			skb_copy_bits(rx->skb, hdrlen + 3, &keyid, 1);
1968 			keyidx = keyid >> 6;
1969 		}
1970 
1971 		/* check per-station GTK first, if multicast packet */
1972 		if (is_multicast_ether_addr(hdr->addr1) && rx->sta)
1973 			rx->key = rcu_dereference(rx->sta->gtk[keyidx]);
1974 
1975 		/* if not found, try default key */
1976 		if (!rx->key) {
1977 			rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
1978 
1979 			/*
1980 			 * RSNA-protected unicast frames should always be
1981 			 * sent with pairwise or station-to-station keys,
1982 			 * but for WEP we allow using a key index as well.
1983 			 */
1984 			if (rx->key &&
1985 			    rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP40 &&
1986 			    rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP104 &&
1987 			    !is_multicast_ether_addr(hdr->addr1))
1988 				rx->key = NULL;
1989 		}
1990 	}
1991 
1992 	if (rx->key) {
1993 		if (unlikely(rx->key->flags & KEY_FLAG_TAINTED))
1994 			return RX_DROP_MONITOR;
1995 
1996 		/* TODO: add threshold stuff again */
1997 	} else {
1998 		return RX_DROP_MONITOR;
1999 	}
2000 
2001 	switch (rx->key->conf.cipher) {
2002 	case WLAN_CIPHER_SUITE_WEP40:
2003 	case WLAN_CIPHER_SUITE_WEP104:
2004 		result = ieee80211_crypto_wep_decrypt(rx);
2005 		break;
2006 	case WLAN_CIPHER_SUITE_TKIP:
2007 		result = ieee80211_crypto_tkip_decrypt(rx);
2008 		break;
2009 	case WLAN_CIPHER_SUITE_CCMP:
2010 		result = ieee80211_crypto_ccmp_decrypt(
2011 			rx, IEEE80211_CCMP_MIC_LEN);
2012 		break;
2013 	case WLAN_CIPHER_SUITE_CCMP_256:
2014 		result = ieee80211_crypto_ccmp_decrypt(
2015 			rx, IEEE80211_CCMP_256_MIC_LEN);
2016 		break;
2017 	case WLAN_CIPHER_SUITE_AES_CMAC:
2018 		result = ieee80211_crypto_aes_cmac_decrypt(rx);
2019 		break;
2020 	case WLAN_CIPHER_SUITE_BIP_CMAC_256:
2021 		result = ieee80211_crypto_aes_cmac_256_decrypt(rx);
2022 		break;
2023 	case WLAN_CIPHER_SUITE_BIP_GMAC_128:
2024 	case WLAN_CIPHER_SUITE_BIP_GMAC_256:
2025 		result = ieee80211_crypto_aes_gmac_decrypt(rx);
2026 		break;
2027 	case WLAN_CIPHER_SUITE_GCMP:
2028 	case WLAN_CIPHER_SUITE_GCMP_256:
2029 		result = ieee80211_crypto_gcmp_decrypt(rx);
2030 		break;
2031 	default:
2032 		result = ieee80211_crypto_hw_decrypt(rx);
2033 	}
2034 
2035 	/* the hdr variable is invalid after the decrypt handlers */
2036 
2037 	/* either the frame has been decrypted or will be dropped */
2038 	status->flag |= RX_FLAG_DECRYPTED;
2039 
2040 	return result;
2041 }
2042 
2043 static inline struct ieee80211_fragment_entry *
2044 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
2045 			 unsigned int frag, unsigned int seq, int rx_queue,
2046 			 struct sk_buff **skb)
2047 {
2048 	struct ieee80211_fragment_entry *entry;
2049 
2050 	entry = &sdata->fragments[sdata->fragment_next++];
2051 	if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
2052 		sdata->fragment_next = 0;
2053 
2054 	if (!skb_queue_empty(&entry->skb_list))
2055 		__skb_queue_purge(&entry->skb_list);
2056 
2057 	__skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
2058 	*skb = NULL;
2059 	entry->first_frag_time = jiffies;
2060 	entry->seq = seq;
2061 	entry->rx_queue = rx_queue;
2062 	entry->last_frag = frag;
2063 	entry->check_sequential_pn = false;
2064 	entry->extra_len = 0;
2065 
2066 	return entry;
2067 }
2068 
2069 static inline struct ieee80211_fragment_entry *
2070 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
2071 			  unsigned int frag, unsigned int seq,
2072 			  int rx_queue, struct ieee80211_hdr *hdr)
2073 {
2074 	struct ieee80211_fragment_entry *entry;
2075 	int i, idx;
2076 
2077 	idx = sdata->fragment_next;
2078 	for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
2079 		struct ieee80211_hdr *f_hdr;
2080 
2081 		idx--;
2082 		if (idx < 0)
2083 			idx = IEEE80211_FRAGMENT_MAX - 1;
2084 
2085 		entry = &sdata->fragments[idx];
2086 		if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
2087 		    entry->rx_queue != rx_queue ||
2088 		    entry->last_frag + 1 != frag)
2089 			continue;
2090 
2091 		f_hdr = (struct ieee80211_hdr *)entry->skb_list.next->data;
2092 
2093 		/*
2094 		 * Check ftype and addresses are equal, else check next fragment
2095 		 */
2096 		if (((hdr->frame_control ^ f_hdr->frame_control) &
2097 		     cpu_to_le16(IEEE80211_FCTL_FTYPE)) ||
2098 		    !ether_addr_equal(hdr->addr1, f_hdr->addr1) ||
2099 		    !ether_addr_equal(hdr->addr2, f_hdr->addr2))
2100 			continue;
2101 
2102 		if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) {
2103 			__skb_queue_purge(&entry->skb_list);
2104 			continue;
2105 		}
2106 		return entry;
2107 	}
2108 
2109 	return NULL;
2110 }
2111 
2112 static ieee80211_rx_result debug_noinline
2113 ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
2114 {
2115 	struct ieee80211_hdr *hdr;
2116 	u16 sc;
2117 	__le16 fc;
2118 	unsigned int frag, seq;
2119 	struct ieee80211_fragment_entry *entry;
2120 	struct sk_buff *skb;
2121 
2122 	hdr = (struct ieee80211_hdr *)rx->skb->data;
2123 	fc = hdr->frame_control;
2124 
2125 	if (ieee80211_is_ctl(fc))
2126 		return RX_CONTINUE;
2127 
2128 	sc = le16_to_cpu(hdr->seq_ctrl);
2129 	frag = sc & IEEE80211_SCTL_FRAG;
2130 
2131 	if (is_multicast_ether_addr(hdr->addr1)) {
2132 		I802_DEBUG_INC(rx->local->dot11MulticastReceivedFrameCount);
2133 		goto out_no_led;
2134 	}
2135 
2136 	if (likely(!ieee80211_has_morefrags(fc) && frag == 0))
2137 		goto out;
2138 
2139 	I802_DEBUG_INC(rx->local->rx_handlers_fragments);
2140 
2141 	if (skb_linearize(rx->skb))
2142 		return RX_DROP_UNUSABLE;
2143 
2144 	/*
2145 	 *  skb_linearize() might change the skb->data and
2146 	 *  previously cached variables (in this case, hdr) need to
2147 	 *  be refreshed with the new data.
2148 	 */
2149 	hdr = (struct ieee80211_hdr *)rx->skb->data;
2150 	seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
2151 
2152 	if (frag == 0) {
2153 		/* This is the first fragment of a new frame. */
2154 		entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
2155 						 rx->seqno_idx, &(rx->skb));
2156 		if (rx->key &&
2157 		    (rx->key->conf.cipher == WLAN_CIPHER_SUITE_CCMP ||
2158 		     rx->key->conf.cipher == WLAN_CIPHER_SUITE_CCMP_256 ||
2159 		     rx->key->conf.cipher == WLAN_CIPHER_SUITE_GCMP ||
2160 		     rx->key->conf.cipher == WLAN_CIPHER_SUITE_GCMP_256) &&
2161 		    ieee80211_has_protected(fc)) {
2162 			int queue = rx->security_idx;
2163 
2164 			/* Store CCMP/GCMP PN so that we can verify that the
2165 			 * next fragment has a sequential PN value.
2166 			 */
2167 			entry->check_sequential_pn = true;
2168 			memcpy(entry->last_pn,
2169 			       rx->key->u.ccmp.rx_pn[queue],
2170 			       IEEE80211_CCMP_PN_LEN);
2171 			BUILD_BUG_ON(offsetof(struct ieee80211_key,
2172 					      u.ccmp.rx_pn) !=
2173 				     offsetof(struct ieee80211_key,
2174 					      u.gcmp.rx_pn));
2175 			BUILD_BUG_ON(sizeof(rx->key->u.ccmp.rx_pn[queue]) !=
2176 				     sizeof(rx->key->u.gcmp.rx_pn[queue]));
2177 			BUILD_BUG_ON(IEEE80211_CCMP_PN_LEN !=
2178 				     IEEE80211_GCMP_PN_LEN);
2179 		}
2180 		return RX_QUEUED;
2181 	}
2182 
2183 	/* This is a fragment for a frame that should already be pending in
2184 	 * fragment cache. Add this fragment to the end of the pending entry.
2185 	 */
2186 	entry = ieee80211_reassemble_find(rx->sdata, frag, seq,
2187 					  rx->seqno_idx, hdr);
2188 	if (!entry) {
2189 		I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
2190 		return RX_DROP_MONITOR;
2191 	}
2192 
2193 	/* "The receiver shall discard MSDUs and MMPDUs whose constituent
2194 	 *  MPDU PN values are not incrementing in steps of 1."
2195 	 * see IEEE P802.11-REVmc/D5.0, 12.5.3.4.4, item d (for CCMP)
2196 	 * and IEEE P802.11-REVmc/D5.0, 12.5.5.4.4, item d (for GCMP)
2197 	 */
2198 	if (entry->check_sequential_pn) {
2199 		int i;
2200 		u8 pn[IEEE80211_CCMP_PN_LEN], *rpn;
2201 		int queue;
2202 
2203 		if (!rx->key ||
2204 		    (rx->key->conf.cipher != WLAN_CIPHER_SUITE_CCMP &&
2205 		     rx->key->conf.cipher != WLAN_CIPHER_SUITE_CCMP_256 &&
2206 		     rx->key->conf.cipher != WLAN_CIPHER_SUITE_GCMP &&
2207 		     rx->key->conf.cipher != WLAN_CIPHER_SUITE_GCMP_256))
2208 			return RX_DROP_UNUSABLE;
2209 		memcpy(pn, entry->last_pn, IEEE80211_CCMP_PN_LEN);
2210 		for (i = IEEE80211_CCMP_PN_LEN - 1; i >= 0; i--) {
2211 			pn[i]++;
2212 			if (pn[i])
2213 				break;
2214 		}
2215 		queue = rx->security_idx;
2216 		rpn = rx->key->u.ccmp.rx_pn[queue];
2217 		if (memcmp(pn, rpn, IEEE80211_CCMP_PN_LEN))
2218 			return RX_DROP_UNUSABLE;
2219 		memcpy(entry->last_pn, pn, IEEE80211_CCMP_PN_LEN);
2220 	}
2221 
2222 	skb_pull(rx->skb, ieee80211_hdrlen(fc));
2223 	__skb_queue_tail(&entry->skb_list, rx->skb);
2224 	entry->last_frag = frag;
2225 	entry->extra_len += rx->skb->len;
2226 	if (ieee80211_has_morefrags(fc)) {
2227 		rx->skb = NULL;
2228 		return RX_QUEUED;
2229 	}
2230 
2231 	rx->skb = __skb_dequeue(&entry->skb_list);
2232 	if (skb_tailroom(rx->skb) < entry->extra_len) {
2233 		I802_DEBUG_INC(rx->local->rx_expand_skb_head_defrag);
2234 		if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
2235 					      GFP_ATOMIC))) {
2236 			I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
2237 			__skb_queue_purge(&entry->skb_list);
2238 			return RX_DROP_UNUSABLE;
2239 		}
2240 	}
2241 	while ((skb = __skb_dequeue(&entry->skb_list))) {
2242 		skb_put_data(rx->skb, skb->data, skb->len);
2243 		dev_kfree_skb(skb);
2244 	}
2245 
2246  out:
2247 	ieee80211_led_rx(rx->local);
2248  out_no_led:
2249 	if (rx->sta)
2250 		rx->sta->rx_stats.packets++;
2251 	return RX_CONTINUE;
2252 }
2253 
2254 static int ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx)
2255 {
2256 	if (unlikely(!rx->sta || !test_sta_flag(rx->sta, WLAN_STA_AUTHORIZED)))
2257 		return -EACCES;
2258 
2259 	return 0;
2260 }
2261 
2262 static int ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx, __le16 fc)
2263 {
2264 	struct sk_buff *skb = rx->skb;
2265 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2266 
2267 	/*
2268 	 * Pass through unencrypted frames if the hardware has
2269 	 * decrypted them already.
2270 	 */
2271 	if (status->flag & RX_FLAG_DECRYPTED)
2272 		return 0;
2273 
2274 	/* Drop unencrypted frames if key is set. */
2275 	if (unlikely(!ieee80211_has_protected(fc) &&
2276 		     !ieee80211_is_nullfunc(fc) &&
2277 		     ieee80211_is_data(fc) && rx->key))
2278 		return -EACCES;
2279 
2280 	return 0;
2281 }
2282 
2283 static int ieee80211_drop_unencrypted_mgmt(struct ieee80211_rx_data *rx)
2284 {
2285 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
2286 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2287 	__le16 fc = hdr->frame_control;
2288 
2289 	/*
2290 	 * Pass through unencrypted frames if the hardware has
2291 	 * decrypted them already.
2292 	 */
2293 	if (status->flag & RX_FLAG_DECRYPTED)
2294 		return 0;
2295 
2296 	if (rx->sta && test_sta_flag(rx->sta, WLAN_STA_MFP)) {
2297 		if (unlikely(!ieee80211_has_protected(fc) &&
2298 			     ieee80211_is_unicast_robust_mgmt_frame(rx->skb) &&
2299 			     rx->key)) {
2300 			if (ieee80211_is_deauth(fc) ||
2301 			    ieee80211_is_disassoc(fc))
2302 				cfg80211_rx_unprot_mlme_mgmt(rx->sdata->dev,
2303 							     rx->skb->data,
2304 							     rx->skb->len);
2305 			return -EACCES;
2306 		}
2307 		/* BIP does not use Protected field, so need to check MMIE */
2308 		if (unlikely(ieee80211_is_multicast_robust_mgmt_frame(rx->skb) &&
2309 			     ieee80211_get_mmie_keyidx(rx->skb) < 0)) {
2310 			if (ieee80211_is_deauth(fc) ||
2311 			    ieee80211_is_disassoc(fc))
2312 				cfg80211_rx_unprot_mlme_mgmt(rx->sdata->dev,
2313 							     rx->skb->data,
2314 							     rx->skb->len);
2315 			return -EACCES;
2316 		}
2317 		/*
2318 		 * When using MFP, Action frames are not allowed prior to
2319 		 * having configured keys.
2320 		 */
2321 		if (unlikely(ieee80211_is_action(fc) && !rx->key &&
2322 			     ieee80211_is_robust_mgmt_frame(rx->skb)))
2323 			return -EACCES;
2324 	}
2325 
2326 	return 0;
2327 }
2328 
2329 static int
2330 __ieee80211_data_to_8023(struct ieee80211_rx_data *rx, bool *port_control)
2331 {
2332 	struct ieee80211_sub_if_data *sdata = rx->sdata;
2333 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
2334 	bool check_port_control = false;
2335 	struct ethhdr *ehdr;
2336 	int ret;
2337 
2338 	*port_control = false;
2339 	if (ieee80211_has_a4(hdr->frame_control) &&
2340 	    sdata->vif.type == NL80211_IFTYPE_AP_VLAN && !sdata->u.vlan.sta)
2341 		return -1;
2342 
2343 	if (sdata->vif.type == NL80211_IFTYPE_STATION &&
2344 	    !!sdata->u.mgd.use_4addr != !!ieee80211_has_a4(hdr->frame_control)) {
2345 
2346 		if (!sdata->u.mgd.use_4addr)
2347 			return -1;
2348 		else if (!ether_addr_equal(hdr->addr1, sdata->vif.addr))
2349 			check_port_control = true;
2350 	}
2351 
2352 	if (is_multicast_ether_addr(hdr->addr1) &&
2353 	    sdata->vif.type == NL80211_IFTYPE_AP_VLAN && sdata->u.vlan.sta)
2354 		return -1;
2355 
2356 	ret = ieee80211_data_to_8023(rx->skb, sdata->vif.addr, sdata->vif.type);
2357 	if (ret < 0)
2358 		return ret;
2359 
2360 	ehdr = (struct ethhdr *) rx->skb->data;
2361 	if (ehdr->h_proto == rx->sdata->control_port_protocol)
2362 		*port_control = true;
2363 	else if (check_port_control)
2364 		return -1;
2365 
2366 	return 0;
2367 }
2368 
2369 /*
2370  * requires that rx->skb is a frame with ethernet header
2371  */
2372 static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx, __le16 fc)
2373 {
2374 	static const u8 pae_group_addr[ETH_ALEN] __aligned(2)
2375 		= { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 };
2376 	struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
2377 
2378 	/*
2379 	 * Allow EAPOL frames to us/the PAE group address regardless
2380 	 * of whether the frame was encrypted or not.
2381 	 */
2382 	if (ehdr->h_proto == rx->sdata->control_port_protocol &&
2383 	    (ether_addr_equal(ehdr->h_dest, rx->sdata->vif.addr) ||
2384 	     ether_addr_equal(ehdr->h_dest, pae_group_addr)))
2385 		return true;
2386 
2387 	if (ieee80211_802_1x_port_control(rx) ||
2388 	    ieee80211_drop_unencrypted(rx, fc))
2389 		return false;
2390 
2391 	return true;
2392 }
2393 
2394 static void ieee80211_deliver_skb_to_local_stack(struct sk_buff *skb,
2395 						 struct ieee80211_rx_data *rx)
2396 {
2397 	struct ieee80211_sub_if_data *sdata = rx->sdata;
2398 	struct net_device *dev = sdata->dev;
2399 
2400 	if (unlikely((skb->protocol == sdata->control_port_protocol ||
2401 		      skb->protocol == cpu_to_be16(ETH_P_PREAUTH)) &&
2402 		     sdata->control_port_over_nl80211)) {
2403 		struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2404 		bool noencrypt = status->flag & RX_FLAG_DECRYPTED;
2405 
2406 		cfg80211_rx_control_port(dev, skb, noencrypt);
2407 		dev_kfree_skb(skb);
2408 	} else {
2409 		/* deliver to local stack */
2410 		if (rx->napi)
2411 			napi_gro_receive(rx->napi, skb);
2412 		else
2413 			netif_receive_skb(skb);
2414 	}
2415 }
2416 
2417 /*
2418  * requires that rx->skb is a frame with ethernet header
2419  */
2420 static void
2421 ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
2422 {
2423 	struct ieee80211_sub_if_data *sdata = rx->sdata;
2424 	struct net_device *dev = sdata->dev;
2425 	struct sk_buff *skb, *xmit_skb;
2426 	struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
2427 	struct sta_info *dsta;
2428 
2429 	skb = rx->skb;
2430 	xmit_skb = NULL;
2431 
2432 	ieee80211_rx_stats(dev, skb->len);
2433 
2434 	if (rx->sta) {
2435 		/* The seqno index has the same property as needed
2436 		 * for the rx_msdu field, i.e. it is IEEE80211_NUM_TIDS
2437 		 * for non-QoS-data frames. Here we know it's a data
2438 		 * frame, so count MSDUs.
2439 		 */
2440 		u64_stats_update_begin(&rx->sta->rx_stats.syncp);
2441 		rx->sta->rx_stats.msdu[rx->seqno_idx]++;
2442 		u64_stats_update_end(&rx->sta->rx_stats.syncp);
2443 	}
2444 
2445 	if ((sdata->vif.type == NL80211_IFTYPE_AP ||
2446 	     sdata->vif.type == NL80211_IFTYPE_AP_VLAN) &&
2447 	    !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) &&
2448 	    (sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->u.vlan.sta)) {
2449 		if (is_multicast_ether_addr(ehdr->h_dest) &&
2450 		    ieee80211_vif_get_num_mcast_if(sdata) != 0) {
2451 			/*
2452 			 * send multicast frames both to higher layers in
2453 			 * local net stack and back to the wireless medium
2454 			 */
2455 			xmit_skb = skb_copy(skb, GFP_ATOMIC);
2456 			if (!xmit_skb)
2457 				net_info_ratelimited("%s: failed to clone multicast frame\n",
2458 						    dev->name);
2459 		} else if (!is_multicast_ether_addr(ehdr->h_dest)) {
2460 			dsta = sta_info_get(sdata, skb->data);
2461 			if (dsta) {
2462 				/*
2463 				 * The destination station is associated to
2464 				 * this AP (in this VLAN), so send the frame
2465 				 * directly to it and do not pass it to local
2466 				 * net stack.
2467 				 */
2468 				xmit_skb = skb;
2469 				skb = NULL;
2470 			}
2471 		}
2472 	}
2473 
2474 #ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
2475 	if (skb) {
2476 		/* 'align' will only take the values 0 or 2 here since all
2477 		 * frames are required to be aligned to 2-byte boundaries
2478 		 * when being passed to mac80211; the code here works just
2479 		 * as well if that isn't true, but mac80211 assumes it can
2480 		 * access fields as 2-byte aligned (e.g. for ether_addr_equal)
2481 		 */
2482 		int align;
2483 
2484 		align = (unsigned long)(skb->data + sizeof(struct ethhdr)) & 3;
2485 		if (align) {
2486 			if (WARN_ON(skb_headroom(skb) < 3)) {
2487 				dev_kfree_skb(skb);
2488 				skb = NULL;
2489 			} else {
2490 				u8 *data = skb->data;
2491 				size_t len = skb_headlen(skb);
2492 				skb->data -= align;
2493 				memmove(skb->data, data, len);
2494 				skb_set_tail_pointer(skb, len);
2495 			}
2496 		}
2497 	}
2498 #endif
2499 
2500 	if (skb) {
2501 		skb->protocol = eth_type_trans(skb, dev);
2502 		memset(skb->cb, 0, sizeof(skb->cb));
2503 
2504 		ieee80211_deliver_skb_to_local_stack(skb, rx);
2505 	}
2506 
2507 	if (xmit_skb) {
2508 		/*
2509 		 * Send to wireless media and increase priority by 256 to
2510 		 * keep the received priority instead of reclassifying
2511 		 * the frame (see cfg80211_classify8021d).
2512 		 */
2513 		xmit_skb->priority += 256;
2514 		xmit_skb->protocol = htons(ETH_P_802_3);
2515 		skb_reset_network_header(xmit_skb);
2516 		skb_reset_mac_header(xmit_skb);
2517 		dev_queue_xmit(xmit_skb);
2518 	}
2519 }
2520 
2521 static ieee80211_rx_result debug_noinline
2522 __ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx, u8 data_offset)
2523 {
2524 	struct net_device *dev = rx->sdata->dev;
2525 	struct sk_buff *skb = rx->skb;
2526 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
2527 	__le16 fc = hdr->frame_control;
2528 	struct sk_buff_head frame_list;
2529 	struct ethhdr ethhdr;
2530 	const u8 *check_da = ethhdr.h_dest, *check_sa = ethhdr.h_source;
2531 
2532 	if (unlikely(ieee80211_has_a4(hdr->frame_control))) {
2533 		check_da = NULL;
2534 		check_sa = NULL;
2535 	} else switch (rx->sdata->vif.type) {
2536 		case NL80211_IFTYPE_AP:
2537 		case NL80211_IFTYPE_AP_VLAN:
2538 			check_da = NULL;
2539 			break;
2540 		case NL80211_IFTYPE_STATION:
2541 			if (!rx->sta ||
2542 			    !test_sta_flag(rx->sta, WLAN_STA_TDLS_PEER))
2543 				check_sa = NULL;
2544 			break;
2545 		case NL80211_IFTYPE_MESH_POINT:
2546 			check_sa = NULL;
2547 			break;
2548 		default:
2549 			break;
2550 	}
2551 
2552 	skb->dev = dev;
2553 	__skb_queue_head_init(&frame_list);
2554 
2555 	if (ieee80211_data_to_8023_exthdr(skb, &ethhdr,
2556 					  rx->sdata->vif.addr,
2557 					  rx->sdata->vif.type,
2558 					  data_offset))
2559 		return RX_DROP_UNUSABLE;
2560 
2561 	ieee80211_amsdu_to_8023s(skb, &frame_list, dev->dev_addr,
2562 				 rx->sdata->vif.type,
2563 				 rx->local->hw.extra_tx_headroom,
2564 				 check_da, check_sa);
2565 
2566 	while (!skb_queue_empty(&frame_list)) {
2567 		rx->skb = __skb_dequeue(&frame_list);
2568 
2569 		if (!ieee80211_frame_allowed(rx, fc)) {
2570 			dev_kfree_skb(rx->skb);
2571 			continue;
2572 		}
2573 
2574 		ieee80211_deliver_skb(rx);
2575 	}
2576 
2577 	return RX_QUEUED;
2578 }
2579 
2580 static ieee80211_rx_result debug_noinline
2581 ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx)
2582 {
2583 	struct sk_buff *skb = rx->skb;
2584 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2585 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
2586 	__le16 fc = hdr->frame_control;
2587 
2588 	if (!(status->rx_flags & IEEE80211_RX_AMSDU))
2589 		return RX_CONTINUE;
2590 
2591 	if (unlikely(!ieee80211_is_data(fc)))
2592 		return RX_CONTINUE;
2593 
2594 	if (unlikely(!ieee80211_is_data_present(fc)))
2595 		return RX_DROP_MONITOR;
2596 
2597 	if (unlikely(ieee80211_has_a4(hdr->frame_control))) {
2598 		switch (rx->sdata->vif.type) {
2599 		case NL80211_IFTYPE_AP_VLAN:
2600 			if (!rx->sdata->u.vlan.sta)
2601 				return RX_DROP_UNUSABLE;
2602 			break;
2603 		case NL80211_IFTYPE_STATION:
2604 			if (!rx->sdata->u.mgd.use_4addr)
2605 				return RX_DROP_UNUSABLE;
2606 			break;
2607 		default:
2608 			return RX_DROP_UNUSABLE;
2609 		}
2610 	}
2611 
2612 	if (is_multicast_ether_addr(hdr->addr1))
2613 		return RX_DROP_UNUSABLE;
2614 
2615 	return __ieee80211_rx_h_amsdu(rx, 0);
2616 }
2617 
2618 #ifdef CONFIG_MAC80211_MESH
2619 static ieee80211_rx_result
2620 ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx)
2621 {
2622 	struct ieee80211_hdr *fwd_hdr, *hdr;
2623 	struct ieee80211_tx_info *info;
2624 	struct ieee80211s_hdr *mesh_hdr;
2625 	struct sk_buff *skb = rx->skb, *fwd_skb;
2626 	struct ieee80211_local *local = rx->local;
2627 	struct ieee80211_sub_if_data *sdata = rx->sdata;
2628 	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
2629 	u16 ac, q, hdrlen;
2630 
2631 	hdr = (struct ieee80211_hdr *) skb->data;
2632 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
2633 
2634 	/* make sure fixed part of mesh header is there, also checks skb len */
2635 	if (!pskb_may_pull(rx->skb, hdrlen + 6))
2636 		return RX_DROP_MONITOR;
2637 
2638 	mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
2639 
2640 	/* make sure full mesh header is there, also checks skb len */
2641 	if (!pskb_may_pull(rx->skb,
2642 			   hdrlen + ieee80211_get_mesh_hdrlen(mesh_hdr)))
2643 		return RX_DROP_MONITOR;
2644 
2645 	/* reload pointers */
2646 	hdr = (struct ieee80211_hdr *) skb->data;
2647 	mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
2648 
2649 	if (ieee80211_drop_unencrypted(rx, hdr->frame_control))
2650 		return RX_DROP_MONITOR;
2651 
2652 	/* frame is in RMC, don't forward */
2653 	if (ieee80211_is_data(hdr->frame_control) &&
2654 	    is_multicast_ether_addr(hdr->addr1) &&
2655 	    mesh_rmc_check(rx->sdata, hdr->addr3, mesh_hdr))
2656 		return RX_DROP_MONITOR;
2657 
2658 	if (!ieee80211_is_data(hdr->frame_control))
2659 		return RX_CONTINUE;
2660 
2661 	if (!mesh_hdr->ttl)
2662 		return RX_DROP_MONITOR;
2663 
2664 	if (mesh_hdr->flags & MESH_FLAGS_AE) {
2665 		struct mesh_path *mppath;
2666 		char *proxied_addr;
2667 		char *mpp_addr;
2668 
2669 		if (is_multicast_ether_addr(hdr->addr1)) {
2670 			mpp_addr = hdr->addr3;
2671 			proxied_addr = mesh_hdr->eaddr1;
2672 		} else if ((mesh_hdr->flags & MESH_FLAGS_AE) ==
2673 			    MESH_FLAGS_AE_A5_A6) {
2674 			/* has_a4 already checked in ieee80211_rx_mesh_check */
2675 			mpp_addr = hdr->addr4;
2676 			proxied_addr = mesh_hdr->eaddr2;
2677 		} else {
2678 			return RX_DROP_MONITOR;
2679 		}
2680 
2681 		rcu_read_lock();
2682 		mppath = mpp_path_lookup(sdata, proxied_addr);
2683 		if (!mppath) {
2684 			mpp_path_add(sdata, proxied_addr, mpp_addr);
2685 		} else {
2686 			spin_lock_bh(&mppath->state_lock);
2687 			if (!ether_addr_equal(mppath->mpp, mpp_addr))
2688 				memcpy(mppath->mpp, mpp_addr, ETH_ALEN);
2689 			mppath->exp_time = jiffies;
2690 			spin_unlock_bh(&mppath->state_lock);
2691 		}
2692 		rcu_read_unlock();
2693 	}
2694 
2695 	/* Frame has reached destination.  Don't forward */
2696 	if (!is_multicast_ether_addr(hdr->addr1) &&
2697 	    ether_addr_equal(sdata->vif.addr, hdr->addr3))
2698 		return RX_CONTINUE;
2699 
2700 	ac = ieee80211_select_queue_80211(sdata, skb, hdr);
2701 	q = sdata->vif.hw_queue[ac];
2702 	if (ieee80211_queue_stopped(&local->hw, q)) {
2703 		IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_congestion);
2704 		return RX_DROP_MONITOR;
2705 	}
2706 	skb_set_queue_mapping(skb, q);
2707 
2708 	if (!--mesh_hdr->ttl) {
2709 		IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_ttl);
2710 		goto out;
2711 	}
2712 
2713 	if (!ifmsh->mshcfg.dot11MeshForwarding)
2714 		goto out;
2715 
2716 	fwd_skb = skb_copy_expand(skb, local->tx_headroom +
2717 				       sdata->encrypt_headroom, 0, GFP_ATOMIC);
2718 	if (!fwd_skb)
2719 		goto out;
2720 
2721 	fwd_hdr =  (struct ieee80211_hdr *) fwd_skb->data;
2722 	fwd_hdr->frame_control &= ~cpu_to_le16(IEEE80211_FCTL_RETRY);
2723 	info = IEEE80211_SKB_CB(fwd_skb);
2724 	memset(info, 0, sizeof(*info));
2725 	info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
2726 	info->control.vif = &rx->sdata->vif;
2727 	info->control.jiffies = jiffies;
2728 	if (is_multicast_ether_addr(fwd_hdr->addr1)) {
2729 		IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_mcast);
2730 		memcpy(fwd_hdr->addr2, sdata->vif.addr, ETH_ALEN);
2731 		/* update power mode indication when forwarding */
2732 		ieee80211_mps_set_frame_flags(sdata, NULL, fwd_hdr);
2733 	} else if (!mesh_nexthop_lookup(sdata, fwd_skb)) {
2734 		/* mesh power mode flags updated in mesh_nexthop_lookup */
2735 		IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_unicast);
2736 	} else {
2737 		/* unable to resolve next hop */
2738 		mesh_path_error_tx(sdata, ifmsh->mshcfg.element_ttl,
2739 				   fwd_hdr->addr3, 0,
2740 				   WLAN_REASON_MESH_PATH_NOFORWARD,
2741 				   fwd_hdr->addr2);
2742 		IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_no_route);
2743 		kfree_skb(fwd_skb);
2744 		return RX_DROP_MONITOR;
2745 	}
2746 
2747 	IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_frames);
2748 	ieee80211_add_pending_skb(local, fwd_skb);
2749  out:
2750 	if (is_multicast_ether_addr(hdr->addr1))
2751 		return RX_CONTINUE;
2752 	return RX_DROP_MONITOR;
2753 }
2754 #endif
2755 
2756 static ieee80211_rx_result debug_noinline
2757 ieee80211_rx_h_data(struct ieee80211_rx_data *rx)
2758 {
2759 	struct ieee80211_sub_if_data *sdata = rx->sdata;
2760 	struct ieee80211_local *local = rx->local;
2761 	struct net_device *dev = sdata->dev;
2762 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
2763 	__le16 fc = hdr->frame_control;
2764 	bool port_control;
2765 	int err;
2766 
2767 	if (unlikely(!ieee80211_is_data(hdr->frame_control)))
2768 		return RX_CONTINUE;
2769 
2770 	if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
2771 		return RX_DROP_MONITOR;
2772 
2773 	/*
2774 	 * Send unexpected-4addr-frame event to hostapd. For older versions,
2775 	 * also drop the frame to cooked monitor interfaces.
2776 	 */
2777 	if (ieee80211_has_a4(hdr->frame_control) &&
2778 	    sdata->vif.type == NL80211_IFTYPE_AP) {
2779 		if (rx->sta &&
2780 		    !test_and_set_sta_flag(rx->sta, WLAN_STA_4ADDR_EVENT))
2781 			cfg80211_rx_unexpected_4addr_frame(
2782 				rx->sdata->dev, rx->sta->sta.addr, GFP_ATOMIC);
2783 		return RX_DROP_MONITOR;
2784 	}
2785 
2786 	err = __ieee80211_data_to_8023(rx, &port_control);
2787 	if (unlikely(err))
2788 		return RX_DROP_UNUSABLE;
2789 
2790 	if (!ieee80211_frame_allowed(rx, fc))
2791 		return RX_DROP_MONITOR;
2792 
2793 	/* directly handle TDLS channel switch requests/responses */
2794 	if (unlikely(((struct ethhdr *)rx->skb->data)->h_proto ==
2795 						cpu_to_be16(ETH_P_TDLS))) {
2796 		struct ieee80211_tdls_data *tf = (void *)rx->skb->data;
2797 
2798 		if (pskb_may_pull(rx->skb,
2799 				  offsetof(struct ieee80211_tdls_data, u)) &&
2800 		    tf->payload_type == WLAN_TDLS_SNAP_RFTYPE &&
2801 		    tf->category == WLAN_CATEGORY_TDLS &&
2802 		    (tf->action_code == WLAN_TDLS_CHANNEL_SWITCH_REQUEST ||
2803 		     tf->action_code == WLAN_TDLS_CHANNEL_SWITCH_RESPONSE)) {
2804 			skb_queue_tail(&local->skb_queue_tdls_chsw, rx->skb);
2805 			schedule_work(&local->tdls_chsw_work);
2806 			if (rx->sta)
2807 				rx->sta->rx_stats.packets++;
2808 
2809 			return RX_QUEUED;
2810 		}
2811 	}
2812 
2813 	if (rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
2814 	    unlikely(port_control) && sdata->bss) {
2815 		sdata = container_of(sdata->bss, struct ieee80211_sub_if_data,
2816 				     u.ap);
2817 		dev = sdata->dev;
2818 		rx->sdata = sdata;
2819 	}
2820 
2821 	rx->skb->dev = dev;
2822 
2823 	if (!ieee80211_hw_check(&local->hw, SUPPORTS_DYNAMIC_PS) &&
2824 	    local->ps_sdata && local->hw.conf.dynamic_ps_timeout > 0 &&
2825 	    !is_multicast_ether_addr(
2826 		    ((struct ethhdr *)rx->skb->data)->h_dest) &&
2827 	    (!local->scanning &&
2828 	     !test_bit(SDATA_STATE_OFFCHANNEL, &sdata->state)))
2829 		mod_timer(&local->dynamic_ps_timer, jiffies +
2830 			  msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout));
2831 
2832 	ieee80211_deliver_skb(rx);
2833 
2834 	return RX_QUEUED;
2835 }
2836 
2837 static ieee80211_rx_result debug_noinline
2838 ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx, struct sk_buff_head *frames)
2839 {
2840 	struct sk_buff *skb = rx->skb;
2841 	struct ieee80211_bar *bar = (struct ieee80211_bar *)skb->data;
2842 	struct tid_ampdu_rx *tid_agg_rx;
2843 	u16 start_seq_num;
2844 	u16 tid;
2845 
2846 	if (likely(!ieee80211_is_ctl(bar->frame_control)))
2847 		return RX_CONTINUE;
2848 
2849 	if (ieee80211_is_back_req(bar->frame_control)) {
2850 		struct {
2851 			__le16 control, start_seq_num;
2852 		} __packed bar_data;
2853 		struct ieee80211_event event = {
2854 			.type = BAR_RX_EVENT,
2855 		};
2856 
2857 		if (!rx->sta)
2858 			return RX_DROP_MONITOR;
2859 
2860 		if (skb_copy_bits(skb, offsetof(struct ieee80211_bar, control),
2861 				  &bar_data, sizeof(bar_data)))
2862 			return RX_DROP_MONITOR;
2863 
2864 		tid = le16_to_cpu(bar_data.control) >> 12;
2865 
2866 		if (!test_bit(tid, rx->sta->ampdu_mlme.agg_session_valid) &&
2867 		    !test_and_set_bit(tid, rx->sta->ampdu_mlme.unexpected_agg))
2868 			ieee80211_send_delba(rx->sdata, rx->sta->sta.addr, tid,
2869 					     WLAN_BACK_RECIPIENT,
2870 					     WLAN_REASON_QSTA_REQUIRE_SETUP);
2871 
2872 		tid_agg_rx = rcu_dereference(rx->sta->ampdu_mlme.tid_rx[tid]);
2873 		if (!tid_agg_rx)
2874 			return RX_DROP_MONITOR;
2875 
2876 		start_seq_num = le16_to_cpu(bar_data.start_seq_num) >> 4;
2877 		event.u.ba.tid = tid;
2878 		event.u.ba.ssn = start_seq_num;
2879 		event.u.ba.sta = &rx->sta->sta;
2880 
2881 		/* reset session timer */
2882 		if (tid_agg_rx->timeout)
2883 			mod_timer(&tid_agg_rx->session_timer,
2884 				  TU_TO_EXP_TIME(tid_agg_rx->timeout));
2885 
2886 		spin_lock(&tid_agg_rx->reorder_lock);
2887 		/* release stored frames up to start of BAR */
2888 		ieee80211_release_reorder_frames(rx->sdata, tid_agg_rx,
2889 						 start_seq_num, frames);
2890 		spin_unlock(&tid_agg_rx->reorder_lock);
2891 
2892 		drv_event_callback(rx->local, rx->sdata, &event);
2893 
2894 		kfree_skb(skb);
2895 		return RX_QUEUED;
2896 	}
2897 
2898 	/*
2899 	 * After this point, we only want management frames,
2900 	 * so we can drop all remaining control frames to
2901 	 * cooked monitor interfaces.
2902 	 */
2903 	return RX_DROP_MONITOR;
2904 }
2905 
2906 static void ieee80211_process_sa_query_req(struct ieee80211_sub_if_data *sdata,
2907 					   struct ieee80211_mgmt *mgmt,
2908 					   size_t len)
2909 {
2910 	struct ieee80211_local *local = sdata->local;
2911 	struct sk_buff *skb;
2912 	struct ieee80211_mgmt *resp;
2913 
2914 	if (!ether_addr_equal(mgmt->da, sdata->vif.addr)) {
2915 		/* Not to own unicast address */
2916 		return;
2917 	}
2918 
2919 	if (!ether_addr_equal(mgmt->sa, sdata->u.mgd.bssid) ||
2920 	    !ether_addr_equal(mgmt->bssid, sdata->u.mgd.bssid)) {
2921 		/* Not from the current AP or not associated yet. */
2922 		return;
2923 	}
2924 
2925 	if (len < 24 + 1 + sizeof(resp->u.action.u.sa_query)) {
2926 		/* Too short SA Query request frame */
2927 		return;
2928 	}
2929 
2930 	skb = dev_alloc_skb(sizeof(*resp) + local->hw.extra_tx_headroom);
2931 	if (skb == NULL)
2932 		return;
2933 
2934 	skb_reserve(skb, local->hw.extra_tx_headroom);
2935 	resp = skb_put_zero(skb, 24);
2936 	memcpy(resp->da, mgmt->sa, ETH_ALEN);
2937 	memcpy(resp->sa, sdata->vif.addr, ETH_ALEN);
2938 	memcpy(resp->bssid, sdata->u.mgd.bssid, ETH_ALEN);
2939 	resp->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
2940 					  IEEE80211_STYPE_ACTION);
2941 	skb_put(skb, 1 + sizeof(resp->u.action.u.sa_query));
2942 	resp->u.action.category = WLAN_CATEGORY_SA_QUERY;
2943 	resp->u.action.u.sa_query.action = WLAN_ACTION_SA_QUERY_RESPONSE;
2944 	memcpy(resp->u.action.u.sa_query.trans_id,
2945 	       mgmt->u.action.u.sa_query.trans_id,
2946 	       WLAN_SA_QUERY_TR_ID_LEN);
2947 
2948 	ieee80211_tx_skb(sdata, skb);
2949 }
2950 
2951 static ieee80211_rx_result debug_noinline
2952 ieee80211_rx_h_mgmt_check(struct ieee80211_rx_data *rx)
2953 {
2954 	struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2955 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2956 
2957 	/*
2958 	 * From here on, look only at management frames.
2959 	 * Data and control frames are already handled,
2960 	 * and unknown (reserved) frames are useless.
2961 	 */
2962 	if (rx->skb->len < 24)
2963 		return RX_DROP_MONITOR;
2964 
2965 	if (!ieee80211_is_mgmt(mgmt->frame_control))
2966 		return RX_DROP_MONITOR;
2967 
2968 	if (rx->sdata->vif.type == NL80211_IFTYPE_AP &&
2969 	    ieee80211_is_beacon(mgmt->frame_control) &&
2970 	    !(rx->flags & IEEE80211_RX_BEACON_REPORTED)) {
2971 		int sig = 0;
2972 
2973 		if (ieee80211_hw_check(&rx->local->hw, SIGNAL_DBM) &&
2974 		    !(status->flag & RX_FLAG_NO_SIGNAL_VAL))
2975 			sig = status->signal;
2976 
2977 		cfg80211_report_obss_beacon(rx->local->hw.wiphy,
2978 					    rx->skb->data, rx->skb->len,
2979 					    status->freq, sig);
2980 		rx->flags |= IEEE80211_RX_BEACON_REPORTED;
2981 	}
2982 
2983 	if (ieee80211_drop_unencrypted_mgmt(rx))
2984 		return RX_DROP_UNUSABLE;
2985 
2986 	return RX_CONTINUE;
2987 }
2988 
2989 static ieee80211_rx_result debug_noinline
2990 ieee80211_rx_h_action(struct ieee80211_rx_data *rx)
2991 {
2992 	struct ieee80211_local *local = rx->local;
2993 	struct ieee80211_sub_if_data *sdata = rx->sdata;
2994 	struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2995 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2996 	int len = rx->skb->len;
2997 
2998 	if (!ieee80211_is_action(mgmt->frame_control))
2999 		return RX_CONTINUE;
3000 
3001 	/* drop too small frames */
3002 	if (len < IEEE80211_MIN_ACTION_SIZE)
3003 		return RX_DROP_UNUSABLE;
3004 
3005 	if (!rx->sta && mgmt->u.action.category != WLAN_CATEGORY_PUBLIC &&
3006 	    mgmt->u.action.category != WLAN_CATEGORY_SELF_PROTECTED &&
3007 	    mgmt->u.action.category != WLAN_CATEGORY_SPECTRUM_MGMT)
3008 		return RX_DROP_UNUSABLE;
3009 
3010 	switch (mgmt->u.action.category) {
3011 	case WLAN_CATEGORY_HT:
3012 		/* reject HT action frames from stations not supporting HT */
3013 		if (!rx->sta->sta.ht_cap.ht_supported)
3014 			goto invalid;
3015 
3016 		if (sdata->vif.type != NL80211_IFTYPE_STATION &&
3017 		    sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
3018 		    sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
3019 		    sdata->vif.type != NL80211_IFTYPE_AP &&
3020 		    sdata->vif.type != NL80211_IFTYPE_ADHOC)
3021 			break;
3022 
3023 		/* verify action & smps_control/chanwidth are present */
3024 		if (len < IEEE80211_MIN_ACTION_SIZE + 2)
3025 			goto invalid;
3026 
3027 		switch (mgmt->u.action.u.ht_smps.action) {
3028 		case WLAN_HT_ACTION_SMPS: {
3029 			struct ieee80211_supported_band *sband;
3030 			enum ieee80211_smps_mode smps_mode;
3031 			struct sta_opmode_info sta_opmode = {};
3032 
3033 			/* convert to HT capability */
3034 			switch (mgmt->u.action.u.ht_smps.smps_control) {
3035 			case WLAN_HT_SMPS_CONTROL_DISABLED:
3036 				smps_mode = IEEE80211_SMPS_OFF;
3037 				break;
3038 			case WLAN_HT_SMPS_CONTROL_STATIC:
3039 				smps_mode = IEEE80211_SMPS_STATIC;
3040 				break;
3041 			case WLAN_HT_SMPS_CONTROL_DYNAMIC:
3042 				smps_mode = IEEE80211_SMPS_DYNAMIC;
3043 				break;
3044 			default:
3045 				goto invalid;
3046 			}
3047 
3048 			/* if no change do nothing */
3049 			if (rx->sta->sta.smps_mode == smps_mode)
3050 				goto handled;
3051 			rx->sta->sta.smps_mode = smps_mode;
3052 			sta_opmode.smps_mode =
3053 				ieee80211_smps_mode_to_smps_mode(smps_mode);
3054 			sta_opmode.changed = STA_OPMODE_SMPS_MODE_CHANGED;
3055 
3056 			sband = rx->local->hw.wiphy->bands[status->band];
3057 
3058 			rate_control_rate_update(local, sband, rx->sta,
3059 						 IEEE80211_RC_SMPS_CHANGED);
3060 			cfg80211_sta_opmode_change_notify(sdata->dev,
3061 							  rx->sta->addr,
3062 							  &sta_opmode,
3063 							  GFP_KERNEL);
3064 			goto handled;
3065 		}
3066 		case WLAN_HT_ACTION_NOTIFY_CHANWIDTH: {
3067 			struct ieee80211_supported_band *sband;
3068 			u8 chanwidth = mgmt->u.action.u.ht_notify_cw.chanwidth;
3069 			enum ieee80211_sta_rx_bandwidth max_bw, new_bw;
3070 			struct sta_opmode_info sta_opmode = {};
3071 
3072 			/* If it doesn't support 40 MHz it can't change ... */
3073 			if (!(rx->sta->sta.ht_cap.cap &
3074 					IEEE80211_HT_CAP_SUP_WIDTH_20_40))
3075 				goto handled;
3076 
3077 			if (chanwidth == IEEE80211_HT_CHANWIDTH_20MHZ)
3078 				max_bw = IEEE80211_STA_RX_BW_20;
3079 			else
3080 				max_bw = ieee80211_sta_cap_rx_bw(rx->sta);
3081 
3082 			/* set cur_max_bandwidth and recalc sta bw */
3083 			rx->sta->cur_max_bandwidth = max_bw;
3084 			new_bw = ieee80211_sta_cur_vht_bw(rx->sta);
3085 
3086 			if (rx->sta->sta.bandwidth == new_bw)
3087 				goto handled;
3088 
3089 			rx->sta->sta.bandwidth = new_bw;
3090 			sband = rx->local->hw.wiphy->bands[status->band];
3091 			sta_opmode.bw =
3092 				ieee80211_sta_rx_bw_to_chan_width(rx->sta);
3093 			sta_opmode.changed = STA_OPMODE_MAX_BW_CHANGED;
3094 
3095 			rate_control_rate_update(local, sband, rx->sta,
3096 						 IEEE80211_RC_BW_CHANGED);
3097 			cfg80211_sta_opmode_change_notify(sdata->dev,
3098 							  rx->sta->addr,
3099 							  &sta_opmode,
3100 							  GFP_KERNEL);
3101 			goto handled;
3102 		}
3103 		default:
3104 			goto invalid;
3105 		}
3106 
3107 		break;
3108 	case WLAN_CATEGORY_PUBLIC:
3109 		if (len < IEEE80211_MIN_ACTION_SIZE + 1)
3110 			goto invalid;
3111 		if (sdata->vif.type != NL80211_IFTYPE_STATION)
3112 			break;
3113 		if (!rx->sta)
3114 			break;
3115 		if (!ether_addr_equal(mgmt->bssid, sdata->u.mgd.bssid))
3116 			break;
3117 		if (mgmt->u.action.u.ext_chan_switch.action_code !=
3118 				WLAN_PUB_ACTION_EXT_CHANSW_ANN)
3119 			break;
3120 		if (len < offsetof(struct ieee80211_mgmt,
3121 				   u.action.u.ext_chan_switch.variable))
3122 			goto invalid;
3123 		goto queue;
3124 	case WLAN_CATEGORY_VHT:
3125 		if (sdata->vif.type != NL80211_IFTYPE_STATION &&
3126 		    sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
3127 		    sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
3128 		    sdata->vif.type != NL80211_IFTYPE_AP &&
3129 		    sdata->vif.type != NL80211_IFTYPE_ADHOC)
3130 			break;
3131 
3132 		/* verify action code is present */
3133 		if (len < IEEE80211_MIN_ACTION_SIZE + 1)
3134 			goto invalid;
3135 
3136 		switch (mgmt->u.action.u.vht_opmode_notif.action_code) {
3137 		case WLAN_VHT_ACTION_OPMODE_NOTIF: {
3138 			/* verify opmode is present */
3139 			if (len < IEEE80211_MIN_ACTION_SIZE + 2)
3140 				goto invalid;
3141 			goto queue;
3142 		}
3143 		case WLAN_VHT_ACTION_GROUPID_MGMT: {
3144 			if (len < IEEE80211_MIN_ACTION_SIZE + 25)
3145 				goto invalid;
3146 			goto queue;
3147 		}
3148 		default:
3149 			break;
3150 		}
3151 		break;
3152 	case WLAN_CATEGORY_BACK:
3153 		if (sdata->vif.type != NL80211_IFTYPE_STATION &&
3154 		    sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
3155 		    sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
3156 		    sdata->vif.type != NL80211_IFTYPE_AP &&
3157 		    sdata->vif.type != NL80211_IFTYPE_ADHOC)
3158 			break;
3159 
3160 		/* verify action_code is present */
3161 		if (len < IEEE80211_MIN_ACTION_SIZE + 1)
3162 			break;
3163 
3164 		switch (mgmt->u.action.u.addba_req.action_code) {
3165 		case WLAN_ACTION_ADDBA_REQ:
3166 			if (len < (IEEE80211_MIN_ACTION_SIZE +
3167 				   sizeof(mgmt->u.action.u.addba_req)))
3168 				goto invalid;
3169 			break;
3170 		case WLAN_ACTION_ADDBA_RESP:
3171 			if (len < (IEEE80211_MIN_ACTION_SIZE +
3172 				   sizeof(mgmt->u.action.u.addba_resp)))
3173 				goto invalid;
3174 			break;
3175 		case WLAN_ACTION_DELBA:
3176 			if (len < (IEEE80211_MIN_ACTION_SIZE +
3177 				   sizeof(mgmt->u.action.u.delba)))
3178 				goto invalid;
3179 			break;
3180 		default:
3181 			goto invalid;
3182 		}
3183 
3184 		goto queue;
3185 	case WLAN_CATEGORY_SPECTRUM_MGMT:
3186 		/* verify action_code is present */
3187 		if (len < IEEE80211_MIN_ACTION_SIZE + 1)
3188 			break;
3189 
3190 		switch (mgmt->u.action.u.measurement.action_code) {
3191 		case WLAN_ACTION_SPCT_MSR_REQ:
3192 			if (status->band != NL80211_BAND_5GHZ)
3193 				break;
3194 
3195 			if (len < (IEEE80211_MIN_ACTION_SIZE +
3196 				   sizeof(mgmt->u.action.u.measurement)))
3197 				break;
3198 
3199 			if (sdata->vif.type != NL80211_IFTYPE_STATION)
3200 				break;
3201 
3202 			ieee80211_process_measurement_req(sdata, mgmt, len);
3203 			goto handled;
3204 		case WLAN_ACTION_SPCT_CHL_SWITCH: {
3205 			u8 *bssid;
3206 			if (len < (IEEE80211_MIN_ACTION_SIZE +
3207 				   sizeof(mgmt->u.action.u.chan_switch)))
3208 				break;
3209 
3210 			if (sdata->vif.type != NL80211_IFTYPE_STATION &&
3211 			    sdata->vif.type != NL80211_IFTYPE_ADHOC &&
3212 			    sdata->vif.type != NL80211_IFTYPE_MESH_POINT)
3213 				break;
3214 
3215 			if (sdata->vif.type == NL80211_IFTYPE_STATION)
3216 				bssid = sdata->u.mgd.bssid;
3217 			else if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
3218 				bssid = sdata->u.ibss.bssid;
3219 			else if (sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
3220 				bssid = mgmt->sa;
3221 			else
3222 				break;
3223 
3224 			if (!ether_addr_equal(mgmt->bssid, bssid))
3225 				break;
3226 
3227 			goto queue;
3228 			}
3229 		}
3230 		break;
3231 	case WLAN_CATEGORY_SA_QUERY:
3232 		if (len < (IEEE80211_MIN_ACTION_SIZE +
3233 			   sizeof(mgmt->u.action.u.sa_query)))
3234 			break;
3235 
3236 		switch (mgmt->u.action.u.sa_query.action) {
3237 		case WLAN_ACTION_SA_QUERY_REQUEST:
3238 			if (sdata->vif.type != NL80211_IFTYPE_STATION)
3239 				break;
3240 			ieee80211_process_sa_query_req(sdata, mgmt, len);
3241 			goto handled;
3242 		}
3243 		break;
3244 	case WLAN_CATEGORY_SELF_PROTECTED:
3245 		if (len < (IEEE80211_MIN_ACTION_SIZE +
3246 			   sizeof(mgmt->u.action.u.self_prot.action_code)))
3247 			break;
3248 
3249 		switch (mgmt->u.action.u.self_prot.action_code) {
3250 		case WLAN_SP_MESH_PEERING_OPEN:
3251 		case WLAN_SP_MESH_PEERING_CLOSE:
3252 		case WLAN_SP_MESH_PEERING_CONFIRM:
3253 			if (!ieee80211_vif_is_mesh(&sdata->vif))
3254 				goto invalid;
3255 			if (sdata->u.mesh.user_mpm)
3256 				/* userspace handles this frame */
3257 				break;
3258 			goto queue;
3259 		case WLAN_SP_MGK_INFORM:
3260 		case WLAN_SP_MGK_ACK:
3261 			if (!ieee80211_vif_is_mesh(&sdata->vif))
3262 				goto invalid;
3263 			break;
3264 		}
3265 		break;
3266 	case WLAN_CATEGORY_MESH_ACTION:
3267 		if (len < (IEEE80211_MIN_ACTION_SIZE +
3268 			   sizeof(mgmt->u.action.u.mesh_action.action_code)))
3269 			break;
3270 
3271 		if (!ieee80211_vif_is_mesh(&sdata->vif))
3272 			break;
3273 		if (mesh_action_is_path_sel(mgmt) &&
3274 		    !mesh_path_sel_is_hwmp(sdata))
3275 			break;
3276 		goto queue;
3277 	}
3278 
3279 	return RX_CONTINUE;
3280 
3281  invalid:
3282 	status->rx_flags |= IEEE80211_RX_MALFORMED_ACTION_FRM;
3283 	/* will return in the next handlers */
3284 	return RX_CONTINUE;
3285 
3286  handled:
3287 	if (rx->sta)
3288 		rx->sta->rx_stats.packets++;
3289 	dev_kfree_skb(rx->skb);
3290 	return RX_QUEUED;
3291 
3292  queue:
3293 	skb_queue_tail(&sdata->skb_queue, rx->skb);
3294 	ieee80211_queue_work(&local->hw, &sdata->work);
3295 	if (rx->sta)
3296 		rx->sta->rx_stats.packets++;
3297 	return RX_QUEUED;
3298 }
3299 
3300 static ieee80211_rx_result debug_noinline
3301 ieee80211_rx_h_userspace_mgmt(struct ieee80211_rx_data *rx)
3302 {
3303 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
3304 	int sig = 0;
3305 
3306 	/* skip known-bad action frames and return them in the next handler */
3307 	if (status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM)
3308 		return RX_CONTINUE;
3309 
3310 	/*
3311 	 * Getting here means the kernel doesn't know how to handle
3312 	 * it, but maybe userspace does ... include returned frames
3313 	 * so userspace can register for those to know whether ones
3314 	 * it transmitted were processed or returned.
3315 	 */
3316 
3317 	if (ieee80211_hw_check(&rx->local->hw, SIGNAL_DBM) &&
3318 	    !(status->flag & RX_FLAG_NO_SIGNAL_VAL))
3319 		sig = status->signal;
3320 
3321 	if (cfg80211_rx_mgmt(&rx->sdata->wdev, status->freq, sig,
3322 			     rx->skb->data, rx->skb->len, 0)) {
3323 		if (rx->sta)
3324 			rx->sta->rx_stats.packets++;
3325 		dev_kfree_skb(rx->skb);
3326 		return RX_QUEUED;
3327 	}
3328 
3329 	return RX_CONTINUE;
3330 }
3331 
3332 static ieee80211_rx_result debug_noinline
3333 ieee80211_rx_h_action_return(struct ieee80211_rx_data *rx)
3334 {
3335 	struct ieee80211_local *local = rx->local;
3336 	struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
3337 	struct sk_buff *nskb;
3338 	struct ieee80211_sub_if_data *sdata = rx->sdata;
3339 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
3340 
3341 	if (!ieee80211_is_action(mgmt->frame_control))
3342 		return RX_CONTINUE;
3343 
3344 	/*
3345 	 * For AP mode, hostapd is responsible for handling any action
3346 	 * frames that we didn't handle, including returning unknown
3347 	 * ones. For all other modes we will return them to the sender,
3348 	 * setting the 0x80 bit in the action category, as required by
3349 	 * 802.11-2012 9.24.4.
3350 	 * Newer versions of hostapd shall also use the management frame
3351 	 * registration mechanisms, but older ones still use cooked
3352 	 * monitor interfaces so push all frames there.
3353 	 */
3354 	if (!(status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM) &&
3355 	    (sdata->vif.type == NL80211_IFTYPE_AP ||
3356 	     sdata->vif.type == NL80211_IFTYPE_AP_VLAN))
3357 		return RX_DROP_MONITOR;
3358 
3359 	if (is_multicast_ether_addr(mgmt->da))
3360 		return RX_DROP_MONITOR;
3361 
3362 	/* do not return rejected action frames */
3363 	if (mgmt->u.action.category & 0x80)
3364 		return RX_DROP_UNUSABLE;
3365 
3366 	nskb = skb_copy_expand(rx->skb, local->hw.extra_tx_headroom, 0,
3367 			       GFP_ATOMIC);
3368 	if (nskb) {
3369 		struct ieee80211_mgmt *nmgmt = (void *)nskb->data;
3370 
3371 		nmgmt->u.action.category |= 0x80;
3372 		memcpy(nmgmt->da, nmgmt->sa, ETH_ALEN);
3373 		memcpy(nmgmt->sa, rx->sdata->vif.addr, ETH_ALEN);
3374 
3375 		memset(nskb->cb, 0, sizeof(nskb->cb));
3376 
3377 		if (rx->sdata->vif.type == NL80211_IFTYPE_P2P_DEVICE) {
3378 			struct ieee80211_tx_info *info = IEEE80211_SKB_CB(nskb);
3379 
3380 			info->flags = IEEE80211_TX_CTL_TX_OFFCHAN |
3381 				      IEEE80211_TX_INTFL_OFFCHAN_TX_OK |
3382 				      IEEE80211_TX_CTL_NO_CCK_RATE;
3383 			if (ieee80211_hw_check(&local->hw, QUEUE_CONTROL))
3384 				info->hw_queue =
3385 					local->hw.offchannel_tx_hw_queue;
3386 		}
3387 
3388 		__ieee80211_tx_skb_tid_band(rx->sdata, nskb, 7,
3389 					    status->band, 0);
3390 	}
3391 	dev_kfree_skb(rx->skb);
3392 	return RX_QUEUED;
3393 }
3394 
3395 static ieee80211_rx_result debug_noinline
3396 ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx)
3397 {
3398 	struct ieee80211_sub_if_data *sdata = rx->sdata;
3399 	struct ieee80211_mgmt *mgmt = (void *)rx->skb->data;
3400 	__le16 stype;
3401 
3402 	stype = mgmt->frame_control & cpu_to_le16(IEEE80211_FCTL_STYPE);
3403 
3404 	if (!ieee80211_vif_is_mesh(&sdata->vif) &&
3405 	    sdata->vif.type != NL80211_IFTYPE_ADHOC &&
3406 	    sdata->vif.type != NL80211_IFTYPE_OCB &&
3407 	    sdata->vif.type != NL80211_IFTYPE_STATION)
3408 		return RX_DROP_MONITOR;
3409 
3410 	switch (stype) {
3411 	case cpu_to_le16(IEEE80211_STYPE_AUTH):
3412 	case cpu_to_le16(IEEE80211_STYPE_BEACON):
3413 	case cpu_to_le16(IEEE80211_STYPE_PROBE_RESP):
3414 		/* process for all: mesh, mlme, ibss */
3415 		break;
3416 	case cpu_to_le16(IEEE80211_STYPE_ASSOC_RESP):
3417 	case cpu_to_le16(IEEE80211_STYPE_REASSOC_RESP):
3418 	case cpu_to_le16(IEEE80211_STYPE_DEAUTH):
3419 	case cpu_to_le16(IEEE80211_STYPE_DISASSOC):
3420 		if (is_multicast_ether_addr(mgmt->da) &&
3421 		    !is_broadcast_ether_addr(mgmt->da))
3422 			return RX_DROP_MONITOR;
3423 
3424 		/* process only for station */
3425 		if (sdata->vif.type != NL80211_IFTYPE_STATION)
3426 			return RX_DROP_MONITOR;
3427 		break;
3428 	case cpu_to_le16(IEEE80211_STYPE_PROBE_REQ):
3429 		/* process only for ibss and mesh */
3430 		if (sdata->vif.type != NL80211_IFTYPE_ADHOC &&
3431 		    sdata->vif.type != NL80211_IFTYPE_MESH_POINT)
3432 			return RX_DROP_MONITOR;
3433 		break;
3434 	default:
3435 		return RX_DROP_MONITOR;
3436 	}
3437 
3438 	/* queue up frame and kick off work to process it */
3439 	skb_queue_tail(&sdata->skb_queue, rx->skb);
3440 	ieee80211_queue_work(&rx->local->hw, &sdata->work);
3441 	if (rx->sta)
3442 		rx->sta->rx_stats.packets++;
3443 
3444 	return RX_QUEUED;
3445 }
3446 
3447 static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx,
3448 					struct ieee80211_rate *rate)
3449 {
3450 	struct ieee80211_sub_if_data *sdata;
3451 	struct ieee80211_local *local = rx->local;
3452 	struct sk_buff *skb = rx->skb, *skb2;
3453 	struct net_device *prev_dev = NULL;
3454 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
3455 	int needed_headroom;
3456 
3457 	/*
3458 	 * If cooked monitor has been processed already, then
3459 	 * don't do it again. If not, set the flag.
3460 	 */
3461 	if (rx->flags & IEEE80211_RX_CMNTR)
3462 		goto out_free_skb;
3463 	rx->flags |= IEEE80211_RX_CMNTR;
3464 
3465 	/* If there are no cooked monitor interfaces, just free the SKB */
3466 	if (!local->cooked_mntrs)
3467 		goto out_free_skb;
3468 
3469 	/* vendor data is long removed here */
3470 	status->flag &= ~RX_FLAG_RADIOTAP_VENDOR_DATA;
3471 	/* room for the radiotap header based on driver features */
3472 	needed_headroom = ieee80211_rx_radiotap_hdrlen(local, status, skb);
3473 
3474 	if (skb_headroom(skb) < needed_headroom &&
3475 	    pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC))
3476 		goto out_free_skb;
3477 
3478 	/* prepend radiotap information */
3479 	ieee80211_add_rx_radiotap_header(local, skb, rate, needed_headroom,
3480 					 false);
3481 
3482 	skb_reset_mac_header(skb);
3483 	skb->ip_summed = CHECKSUM_UNNECESSARY;
3484 	skb->pkt_type = PACKET_OTHERHOST;
3485 	skb->protocol = htons(ETH_P_802_2);
3486 
3487 	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
3488 		if (!ieee80211_sdata_running(sdata))
3489 			continue;
3490 
3491 		if (sdata->vif.type != NL80211_IFTYPE_MONITOR ||
3492 		    !(sdata->u.mntr.flags & MONITOR_FLAG_COOK_FRAMES))
3493 			continue;
3494 
3495 		if (prev_dev) {
3496 			skb2 = skb_clone(skb, GFP_ATOMIC);
3497 			if (skb2) {
3498 				skb2->dev = prev_dev;
3499 				netif_receive_skb(skb2);
3500 			}
3501 		}
3502 
3503 		prev_dev = sdata->dev;
3504 		ieee80211_rx_stats(sdata->dev, skb->len);
3505 	}
3506 
3507 	if (prev_dev) {
3508 		skb->dev = prev_dev;
3509 		netif_receive_skb(skb);
3510 		return;
3511 	}
3512 
3513  out_free_skb:
3514 	dev_kfree_skb(skb);
3515 }
3516 
3517 static void ieee80211_rx_handlers_result(struct ieee80211_rx_data *rx,
3518 					 ieee80211_rx_result res)
3519 {
3520 	switch (res) {
3521 	case RX_DROP_MONITOR:
3522 		I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop);
3523 		if (rx->sta)
3524 			rx->sta->rx_stats.dropped++;
3525 		/* fall through */
3526 	case RX_CONTINUE: {
3527 		struct ieee80211_rate *rate = NULL;
3528 		struct ieee80211_supported_band *sband;
3529 		struct ieee80211_rx_status *status;
3530 
3531 		status = IEEE80211_SKB_RXCB((rx->skb));
3532 
3533 		sband = rx->local->hw.wiphy->bands[status->band];
3534 		if (status->encoding == RX_ENC_LEGACY)
3535 			rate = &sband->bitrates[status->rate_idx];
3536 
3537 		ieee80211_rx_cooked_monitor(rx, rate);
3538 		break;
3539 		}
3540 	case RX_DROP_UNUSABLE:
3541 		I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop);
3542 		if (rx->sta)
3543 			rx->sta->rx_stats.dropped++;
3544 		dev_kfree_skb(rx->skb);
3545 		break;
3546 	case RX_QUEUED:
3547 		I802_DEBUG_INC(rx->sdata->local->rx_handlers_queued);
3548 		break;
3549 	}
3550 }
3551 
3552 static void ieee80211_rx_handlers(struct ieee80211_rx_data *rx,
3553 				  struct sk_buff_head *frames)
3554 {
3555 	ieee80211_rx_result res = RX_DROP_MONITOR;
3556 	struct sk_buff *skb;
3557 
3558 #define CALL_RXH(rxh)			\
3559 	do {				\
3560 		res = rxh(rx);		\
3561 		if (res != RX_CONTINUE)	\
3562 			goto rxh_next;  \
3563 	} while (0)
3564 
3565 	/* Lock here to avoid hitting all of the data used in the RX
3566 	 * path (e.g. key data, station data, ...) concurrently when
3567 	 * a frame is released from the reorder buffer due to timeout
3568 	 * from the timer, potentially concurrently with RX from the
3569 	 * driver.
3570 	 */
3571 	spin_lock_bh(&rx->local->rx_path_lock);
3572 
3573 	while ((skb = __skb_dequeue(frames))) {
3574 		/*
3575 		 * all the other fields are valid across frames
3576 		 * that belong to an aMPDU since they are on the
3577 		 * same TID from the same station
3578 		 */
3579 		rx->skb = skb;
3580 
3581 		CALL_RXH(ieee80211_rx_h_check_more_data);
3582 		CALL_RXH(ieee80211_rx_h_uapsd_and_pspoll);
3583 		CALL_RXH(ieee80211_rx_h_sta_process);
3584 		CALL_RXH(ieee80211_rx_h_decrypt);
3585 		CALL_RXH(ieee80211_rx_h_defragment);
3586 		CALL_RXH(ieee80211_rx_h_michael_mic_verify);
3587 		/* must be after MMIC verify so header is counted in MPDU mic */
3588 #ifdef CONFIG_MAC80211_MESH
3589 		if (ieee80211_vif_is_mesh(&rx->sdata->vif))
3590 			CALL_RXH(ieee80211_rx_h_mesh_fwding);
3591 #endif
3592 		CALL_RXH(ieee80211_rx_h_amsdu);
3593 		CALL_RXH(ieee80211_rx_h_data);
3594 
3595 		/* special treatment -- needs the queue */
3596 		res = ieee80211_rx_h_ctrl(rx, frames);
3597 		if (res != RX_CONTINUE)
3598 			goto rxh_next;
3599 
3600 		CALL_RXH(ieee80211_rx_h_mgmt_check);
3601 		CALL_RXH(ieee80211_rx_h_action);
3602 		CALL_RXH(ieee80211_rx_h_userspace_mgmt);
3603 		CALL_RXH(ieee80211_rx_h_action_return);
3604 		CALL_RXH(ieee80211_rx_h_mgmt);
3605 
3606  rxh_next:
3607 		ieee80211_rx_handlers_result(rx, res);
3608 
3609 #undef CALL_RXH
3610 	}
3611 
3612 	spin_unlock_bh(&rx->local->rx_path_lock);
3613 }
3614 
3615 static void ieee80211_invoke_rx_handlers(struct ieee80211_rx_data *rx)
3616 {
3617 	struct sk_buff_head reorder_release;
3618 	ieee80211_rx_result res = RX_DROP_MONITOR;
3619 
3620 	__skb_queue_head_init(&reorder_release);
3621 
3622 #define CALL_RXH(rxh)			\
3623 	do {				\
3624 		res = rxh(rx);		\
3625 		if (res != RX_CONTINUE)	\
3626 			goto rxh_next;  \
3627 	} while (0)
3628 
3629 	CALL_RXH(ieee80211_rx_h_check_dup);
3630 	CALL_RXH(ieee80211_rx_h_check);
3631 
3632 	ieee80211_rx_reorder_ampdu(rx, &reorder_release);
3633 
3634 	ieee80211_rx_handlers(rx, &reorder_release);
3635 	return;
3636 
3637  rxh_next:
3638 	ieee80211_rx_handlers_result(rx, res);
3639 
3640 #undef CALL_RXH
3641 }
3642 
3643 /*
3644  * This function makes calls into the RX path, therefore
3645  * it has to be invoked under RCU read lock.
3646  */
3647 void ieee80211_release_reorder_timeout(struct sta_info *sta, int tid)
3648 {
3649 	struct sk_buff_head frames;
3650 	struct ieee80211_rx_data rx = {
3651 		.sta = sta,
3652 		.sdata = sta->sdata,
3653 		.local = sta->local,
3654 		/* This is OK -- must be QoS data frame */
3655 		.security_idx = tid,
3656 		.seqno_idx = tid,
3657 		.napi = NULL, /* must be NULL to not have races */
3658 	};
3659 	struct tid_ampdu_rx *tid_agg_rx;
3660 
3661 	tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
3662 	if (!tid_agg_rx)
3663 		return;
3664 
3665 	__skb_queue_head_init(&frames);
3666 
3667 	spin_lock(&tid_agg_rx->reorder_lock);
3668 	ieee80211_sta_reorder_release(sta->sdata, tid_agg_rx, &frames);
3669 	spin_unlock(&tid_agg_rx->reorder_lock);
3670 
3671 	if (!skb_queue_empty(&frames)) {
3672 		struct ieee80211_event event = {
3673 			.type = BA_FRAME_TIMEOUT,
3674 			.u.ba.tid = tid,
3675 			.u.ba.sta = &sta->sta,
3676 		};
3677 		drv_event_callback(rx.local, rx.sdata, &event);
3678 	}
3679 
3680 	ieee80211_rx_handlers(&rx, &frames);
3681 }
3682 
3683 void ieee80211_mark_rx_ba_filtered_frames(struct ieee80211_sta *pubsta, u8 tid,
3684 					  u16 ssn, u64 filtered,
3685 					  u16 received_mpdus)
3686 {
3687 	struct sta_info *sta;
3688 	struct tid_ampdu_rx *tid_agg_rx;
3689 	struct sk_buff_head frames;
3690 	struct ieee80211_rx_data rx = {
3691 		/* This is OK -- must be QoS data frame */
3692 		.security_idx = tid,
3693 		.seqno_idx = tid,
3694 	};
3695 	int i, diff;
3696 
3697 	if (WARN_ON(!pubsta || tid >= IEEE80211_NUM_TIDS))
3698 		return;
3699 
3700 	__skb_queue_head_init(&frames);
3701 
3702 	sta = container_of(pubsta, struct sta_info, sta);
3703 
3704 	rx.sta = sta;
3705 	rx.sdata = sta->sdata;
3706 	rx.local = sta->local;
3707 
3708 	rcu_read_lock();
3709 	tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
3710 	if (!tid_agg_rx)
3711 		goto out;
3712 
3713 	spin_lock_bh(&tid_agg_rx->reorder_lock);
3714 
3715 	if (received_mpdus >= IEEE80211_SN_MODULO >> 1) {
3716 		int release;
3717 
3718 		/* release all frames in the reorder buffer */
3719 		release = (tid_agg_rx->head_seq_num + tid_agg_rx->buf_size) %
3720 			   IEEE80211_SN_MODULO;
3721 		ieee80211_release_reorder_frames(sta->sdata, tid_agg_rx,
3722 						 release, &frames);
3723 		/* update ssn to match received ssn */
3724 		tid_agg_rx->head_seq_num = ssn;
3725 	} else {
3726 		ieee80211_release_reorder_frames(sta->sdata, tid_agg_rx, ssn,
3727 						 &frames);
3728 	}
3729 
3730 	/* handle the case that received ssn is behind the mac ssn.
3731 	 * it can be tid_agg_rx->buf_size behind and still be valid */
3732 	diff = (tid_agg_rx->head_seq_num - ssn) & IEEE80211_SN_MASK;
3733 	if (diff >= tid_agg_rx->buf_size) {
3734 		tid_agg_rx->reorder_buf_filtered = 0;
3735 		goto release;
3736 	}
3737 	filtered = filtered >> diff;
3738 	ssn += diff;
3739 
3740 	/* update bitmap */
3741 	for (i = 0; i < tid_agg_rx->buf_size; i++) {
3742 		int index = (ssn + i) % tid_agg_rx->buf_size;
3743 
3744 		tid_agg_rx->reorder_buf_filtered &= ~BIT_ULL(index);
3745 		if (filtered & BIT_ULL(i))
3746 			tid_agg_rx->reorder_buf_filtered |= BIT_ULL(index);
3747 	}
3748 
3749 	/* now process also frames that the filter marking released */
3750 	ieee80211_sta_reorder_release(sta->sdata, tid_agg_rx, &frames);
3751 
3752 release:
3753 	spin_unlock_bh(&tid_agg_rx->reorder_lock);
3754 
3755 	ieee80211_rx_handlers(&rx, &frames);
3756 
3757  out:
3758 	rcu_read_unlock();
3759 }
3760 EXPORT_SYMBOL(ieee80211_mark_rx_ba_filtered_frames);
3761 
3762 /* main receive path */
3763 
3764 static bool ieee80211_accept_frame(struct ieee80211_rx_data *rx)
3765 {
3766 	struct ieee80211_sub_if_data *sdata = rx->sdata;
3767 	struct sk_buff *skb = rx->skb;
3768 	struct ieee80211_hdr *hdr = (void *)skb->data;
3769 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
3770 	u8 *bssid = ieee80211_get_bssid(hdr, skb->len, sdata->vif.type);
3771 	bool multicast = is_multicast_ether_addr(hdr->addr1);
3772 
3773 	switch (sdata->vif.type) {
3774 	case NL80211_IFTYPE_STATION:
3775 		if (!bssid && !sdata->u.mgd.use_4addr)
3776 			return false;
3777 		if (multicast)
3778 			return true;
3779 		return ether_addr_equal(sdata->vif.addr, hdr->addr1);
3780 	case NL80211_IFTYPE_ADHOC:
3781 		if (!bssid)
3782 			return false;
3783 		if (ether_addr_equal(sdata->vif.addr, hdr->addr2) ||
3784 		    ether_addr_equal(sdata->u.ibss.bssid, hdr->addr2))
3785 			return false;
3786 		if (ieee80211_is_beacon(hdr->frame_control))
3787 			return true;
3788 		if (!ieee80211_bssid_match(bssid, sdata->u.ibss.bssid))
3789 			return false;
3790 		if (!multicast &&
3791 		    !ether_addr_equal(sdata->vif.addr, hdr->addr1))
3792 			return false;
3793 		if (!rx->sta) {
3794 			int rate_idx;
3795 			if (status->encoding != RX_ENC_LEGACY)
3796 				rate_idx = 0; /* TODO: HT/VHT rates */
3797 			else
3798 				rate_idx = status->rate_idx;
3799 			ieee80211_ibss_rx_no_sta(sdata, bssid, hdr->addr2,
3800 						 BIT(rate_idx));
3801 		}
3802 		return true;
3803 	case NL80211_IFTYPE_OCB:
3804 		if (!bssid)
3805 			return false;
3806 		if (!ieee80211_is_data_present(hdr->frame_control))
3807 			return false;
3808 		if (!is_broadcast_ether_addr(bssid))
3809 			return false;
3810 		if (!multicast &&
3811 		    !ether_addr_equal(sdata->dev->dev_addr, hdr->addr1))
3812 			return false;
3813 		if (!rx->sta) {
3814 			int rate_idx;
3815 			if (status->encoding != RX_ENC_LEGACY)
3816 				rate_idx = 0; /* TODO: HT rates */
3817 			else
3818 				rate_idx = status->rate_idx;
3819 			ieee80211_ocb_rx_no_sta(sdata, bssid, hdr->addr2,
3820 						BIT(rate_idx));
3821 		}
3822 		return true;
3823 	case NL80211_IFTYPE_MESH_POINT:
3824 		if (ether_addr_equal(sdata->vif.addr, hdr->addr2))
3825 			return false;
3826 		if (multicast)
3827 			return true;
3828 		return ether_addr_equal(sdata->vif.addr, hdr->addr1);
3829 	case NL80211_IFTYPE_AP_VLAN:
3830 	case NL80211_IFTYPE_AP:
3831 		if (!bssid)
3832 			return ether_addr_equal(sdata->vif.addr, hdr->addr1);
3833 
3834 		if (!ieee80211_bssid_match(bssid, sdata->vif.addr)) {
3835 			/*
3836 			 * Accept public action frames even when the
3837 			 * BSSID doesn't match, this is used for P2P
3838 			 * and location updates. Note that mac80211
3839 			 * itself never looks at these frames.
3840 			 */
3841 			if (!multicast &&
3842 			    !ether_addr_equal(sdata->vif.addr, hdr->addr1))
3843 				return false;
3844 			if (ieee80211_is_public_action(hdr, skb->len))
3845 				return true;
3846 			return ieee80211_is_beacon(hdr->frame_control);
3847 		}
3848 
3849 		if (!ieee80211_has_tods(hdr->frame_control)) {
3850 			/* ignore data frames to TDLS-peers */
3851 			if (ieee80211_is_data(hdr->frame_control))
3852 				return false;
3853 			/* ignore action frames to TDLS-peers */
3854 			if (ieee80211_is_action(hdr->frame_control) &&
3855 			    !is_broadcast_ether_addr(bssid) &&
3856 			    !ether_addr_equal(bssid, hdr->addr1))
3857 				return false;
3858 		}
3859 
3860 		/*
3861 		 * 802.11-2016 Table 9-26 says that for data frames, A1 must be
3862 		 * the BSSID - we've checked that already but may have accepted
3863 		 * the wildcard (ff:ff:ff:ff:ff:ff).
3864 		 *
3865 		 * It also says:
3866 		 *	The BSSID of the Data frame is determined as follows:
3867 		 *	a) If the STA is contained within an AP or is associated
3868 		 *	   with an AP, the BSSID is the address currently in use
3869 		 *	   by the STA contained in the AP.
3870 		 *
3871 		 * So we should not accept data frames with an address that's
3872 		 * multicast.
3873 		 *
3874 		 * Accepting it also opens a security problem because stations
3875 		 * could encrypt it with the GTK and inject traffic that way.
3876 		 */
3877 		if (ieee80211_is_data(hdr->frame_control) && multicast)
3878 			return false;
3879 
3880 		return true;
3881 	case NL80211_IFTYPE_WDS:
3882 		if (bssid || !ieee80211_is_data(hdr->frame_control))
3883 			return false;
3884 		return ether_addr_equal(sdata->u.wds.remote_addr, hdr->addr2);
3885 	case NL80211_IFTYPE_P2P_DEVICE:
3886 		return ieee80211_is_public_action(hdr, skb->len) ||
3887 		       ieee80211_is_probe_req(hdr->frame_control) ||
3888 		       ieee80211_is_probe_resp(hdr->frame_control) ||
3889 		       ieee80211_is_beacon(hdr->frame_control);
3890 	case NL80211_IFTYPE_NAN:
3891 		/* Currently no frames on NAN interface are allowed */
3892 		return false;
3893 	default:
3894 		break;
3895 	}
3896 
3897 	WARN_ON_ONCE(1);
3898 	return false;
3899 }
3900 
3901 void ieee80211_check_fast_rx(struct sta_info *sta)
3902 {
3903 	struct ieee80211_sub_if_data *sdata = sta->sdata;
3904 	struct ieee80211_local *local = sdata->local;
3905 	struct ieee80211_key *key;
3906 	struct ieee80211_fast_rx fastrx = {
3907 		.dev = sdata->dev,
3908 		.vif_type = sdata->vif.type,
3909 		.control_port_protocol = sdata->control_port_protocol,
3910 	}, *old, *new = NULL;
3911 	bool assign = false;
3912 
3913 	/* use sparse to check that we don't return without updating */
3914 	__acquire(check_fast_rx);
3915 
3916 	BUILD_BUG_ON(sizeof(fastrx.rfc1042_hdr) != sizeof(rfc1042_header));
3917 	BUILD_BUG_ON(sizeof(fastrx.rfc1042_hdr) != ETH_ALEN);
3918 	ether_addr_copy(fastrx.rfc1042_hdr, rfc1042_header);
3919 	ether_addr_copy(fastrx.vif_addr, sdata->vif.addr);
3920 
3921 	fastrx.uses_rss = ieee80211_hw_check(&local->hw, USES_RSS);
3922 
3923 	/* fast-rx doesn't do reordering */
3924 	if (ieee80211_hw_check(&local->hw, AMPDU_AGGREGATION) &&
3925 	    !ieee80211_hw_check(&local->hw, SUPPORTS_REORDERING_BUFFER))
3926 		goto clear;
3927 
3928 	switch (sdata->vif.type) {
3929 	case NL80211_IFTYPE_STATION:
3930 		if (sta->sta.tdls) {
3931 			fastrx.da_offs = offsetof(struct ieee80211_hdr, addr1);
3932 			fastrx.sa_offs = offsetof(struct ieee80211_hdr, addr2);
3933 			fastrx.expected_ds_bits = 0;
3934 		} else {
3935 			fastrx.sta_notify = sdata->u.mgd.probe_send_count > 0;
3936 			fastrx.da_offs = offsetof(struct ieee80211_hdr, addr1);
3937 			fastrx.sa_offs = offsetof(struct ieee80211_hdr, addr3);
3938 			fastrx.expected_ds_bits =
3939 				cpu_to_le16(IEEE80211_FCTL_FROMDS);
3940 		}
3941 
3942 		if (sdata->u.mgd.use_4addr && !sta->sta.tdls) {
3943 			fastrx.expected_ds_bits |=
3944 				cpu_to_le16(IEEE80211_FCTL_TODS);
3945 			fastrx.da_offs = offsetof(struct ieee80211_hdr, addr3);
3946 			fastrx.sa_offs = offsetof(struct ieee80211_hdr, addr4);
3947 		}
3948 
3949 		if (!sdata->u.mgd.powersave)
3950 			break;
3951 
3952 		/* software powersave is a huge mess, avoid all of it */
3953 		if (ieee80211_hw_check(&local->hw, PS_NULLFUNC_STACK))
3954 			goto clear;
3955 		if (ieee80211_hw_check(&local->hw, SUPPORTS_PS) &&
3956 		    !ieee80211_hw_check(&local->hw, SUPPORTS_DYNAMIC_PS))
3957 			goto clear;
3958 		break;
3959 	case NL80211_IFTYPE_AP_VLAN:
3960 	case NL80211_IFTYPE_AP:
3961 		/* parallel-rx requires this, at least with calls to
3962 		 * ieee80211_sta_ps_transition()
3963 		 */
3964 		if (!ieee80211_hw_check(&local->hw, AP_LINK_PS))
3965 			goto clear;
3966 		fastrx.da_offs = offsetof(struct ieee80211_hdr, addr3);
3967 		fastrx.sa_offs = offsetof(struct ieee80211_hdr, addr2);
3968 		fastrx.expected_ds_bits = cpu_to_le16(IEEE80211_FCTL_TODS);
3969 
3970 		fastrx.internal_forward =
3971 			!(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) &&
3972 			(sdata->vif.type != NL80211_IFTYPE_AP_VLAN ||
3973 			 !sdata->u.vlan.sta);
3974 
3975 		if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
3976 		    sdata->u.vlan.sta) {
3977 			fastrx.expected_ds_bits |=
3978 				cpu_to_le16(IEEE80211_FCTL_FROMDS);
3979 			fastrx.sa_offs = offsetof(struct ieee80211_hdr, addr4);
3980 			fastrx.internal_forward = 0;
3981 		}
3982 
3983 		break;
3984 	default:
3985 		goto clear;
3986 	}
3987 
3988 	if (!test_sta_flag(sta, WLAN_STA_AUTHORIZED))
3989 		goto clear;
3990 
3991 	rcu_read_lock();
3992 	key = rcu_dereference(sta->ptk[sta->ptk_idx]);
3993 	if (key) {
3994 		switch (key->conf.cipher) {
3995 		case WLAN_CIPHER_SUITE_TKIP:
3996 			/* we don't want to deal with MMIC in fast-rx */
3997 			goto clear_rcu;
3998 		case WLAN_CIPHER_SUITE_CCMP:
3999 		case WLAN_CIPHER_SUITE_CCMP_256:
4000 		case WLAN_CIPHER_SUITE_GCMP:
4001 		case WLAN_CIPHER_SUITE_GCMP_256:
4002 			break;
4003 		default:
4004 			/* we also don't want to deal with WEP or cipher scheme
4005 			 * since those require looking up the key idx in the
4006 			 * frame, rather than assuming the PTK is used
4007 			 * (we need to revisit this once we implement the real
4008 			 * PTK index, which is now valid in the spec, but we
4009 			 * haven't implemented that part yet)
4010 			 */
4011 			goto clear_rcu;
4012 		}
4013 
4014 		fastrx.key = true;
4015 		fastrx.icv_len = key->conf.icv_len;
4016 	}
4017 
4018 	assign = true;
4019  clear_rcu:
4020 	rcu_read_unlock();
4021  clear:
4022 	__release(check_fast_rx);
4023 
4024 	if (assign)
4025 		new = kmemdup(&fastrx, sizeof(fastrx), GFP_KERNEL);
4026 
4027 	spin_lock_bh(&sta->lock);
4028 	old = rcu_dereference_protected(sta->fast_rx, true);
4029 	rcu_assign_pointer(sta->fast_rx, new);
4030 	spin_unlock_bh(&sta->lock);
4031 
4032 	if (old)
4033 		kfree_rcu(old, rcu_head);
4034 }
4035 
4036 void ieee80211_clear_fast_rx(struct sta_info *sta)
4037 {
4038 	struct ieee80211_fast_rx *old;
4039 
4040 	spin_lock_bh(&sta->lock);
4041 	old = rcu_dereference_protected(sta->fast_rx, true);
4042 	RCU_INIT_POINTER(sta->fast_rx, NULL);
4043 	spin_unlock_bh(&sta->lock);
4044 
4045 	if (old)
4046 		kfree_rcu(old, rcu_head);
4047 }
4048 
4049 void __ieee80211_check_fast_rx_iface(struct ieee80211_sub_if_data *sdata)
4050 {
4051 	struct ieee80211_local *local = sdata->local;
4052 	struct sta_info *sta;
4053 
4054 	lockdep_assert_held(&local->sta_mtx);
4055 
4056 	list_for_each_entry_rcu(sta, &local->sta_list, list) {
4057 		if (sdata != sta->sdata &&
4058 		    (!sta->sdata->bss || sta->sdata->bss != sdata->bss))
4059 			continue;
4060 		ieee80211_check_fast_rx(sta);
4061 	}
4062 }
4063 
4064 void ieee80211_check_fast_rx_iface(struct ieee80211_sub_if_data *sdata)
4065 {
4066 	struct ieee80211_local *local = sdata->local;
4067 
4068 	mutex_lock(&local->sta_mtx);
4069 	__ieee80211_check_fast_rx_iface(sdata);
4070 	mutex_unlock(&local->sta_mtx);
4071 }
4072 
4073 static bool ieee80211_invoke_fast_rx(struct ieee80211_rx_data *rx,
4074 				     struct ieee80211_fast_rx *fast_rx)
4075 {
4076 	struct sk_buff *skb = rx->skb;
4077 	struct ieee80211_hdr *hdr = (void *)skb->data;
4078 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
4079 	struct sta_info *sta = rx->sta;
4080 	int orig_len = skb->len;
4081 	int hdrlen = ieee80211_hdrlen(hdr->frame_control);
4082 	int snap_offs = hdrlen;
4083 	struct {
4084 		u8 snap[sizeof(rfc1042_header)];
4085 		__be16 proto;
4086 	} *payload __aligned(2);
4087 	struct {
4088 		u8 da[ETH_ALEN];
4089 		u8 sa[ETH_ALEN];
4090 	} addrs __aligned(2);
4091 	struct ieee80211_sta_rx_stats *stats = &sta->rx_stats;
4092 
4093 	if (fast_rx->uses_rss)
4094 		stats = this_cpu_ptr(sta->pcpu_rx_stats);
4095 
4096 	/* for parallel-rx, we need to have DUP_VALIDATED, otherwise we write
4097 	 * to a common data structure; drivers can implement that per queue
4098 	 * but we don't have that information in mac80211
4099 	 */
4100 	if (!(status->flag & RX_FLAG_DUP_VALIDATED))
4101 		return false;
4102 
4103 #define FAST_RX_CRYPT_FLAGS	(RX_FLAG_PN_VALIDATED | RX_FLAG_DECRYPTED)
4104 
4105 	/* If using encryption, we also need to have:
4106 	 *  - PN_VALIDATED: similar, but the implementation is tricky
4107 	 *  - DECRYPTED: necessary for PN_VALIDATED
4108 	 */
4109 	if (fast_rx->key &&
4110 	    (status->flag & FAST_RX_CRYPT_FLAGS) != FAST_RX_CRYPT_FLAGS)
4111 		return false;
4112 
4113 	if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
4114 		return false;
4115 
4116 	if (unlikely(ieee80211_is_frag(hdr)))
4117 		return false;
4118 
4119 	/* Since our interface address cannot be multicast, this
4120 	 * implicitly also rejects multicast frames without the
4121 	 * explicit check.
4122 	 *
4123 	 * We shouldn't get any *data* frames not addressed to us
4124 	 * (AP mode will accept multicast *management* frames), but
4125 	 * punting here will make it go through the full checks in
4126 	 * ieee80211_accept_frame().
4127 	 */
4128 	if (!ether_addr_equal(fast_rx->vif_addr, hdr->addr1))
4129 		return false;
4130 
4131 	if ((hdr->frame_control & cpu_to_le16(IEEE80211_FCTL_FROMDS |
4132 					      IEEE80211_FCTL_TODS)) !=
4133 	    fast_rx->expected_ds_bits)
4134 		return false;
4135 
4136 	/* assign the key to drop unencrypted frames (later)
4137 	 * and strip the IV/MIC if necessary
4138 	 */
4139 	if (fast_rx->key && !(status->flag & RX_FLAG_IV_STRIPPED)) {
4140 		/* GCMP header length is the same */
4141 		snap_offs += IEEE80211_CCMP_HDR_LEN;
4142 	}
4143 
4144 	if (!(status->rx_flags & IEEE80211_RX_AMSDU)) {
4145 		if (!pskb_may_pull(skb, snap_offs + sizeof(*payload)))
4146 			goto drop;
4147 
4148 		payload = (void *)(skb->data + snap_offs);
4149 
4150 		if (!ether_addr_equal(payload->snap, fast_rx->rfc1042_hdr))
4151 			return false;
4152 
4153 		/* Don't handle these here since they require special code.
4154 		 * Accept AARP and IPX even though they should come with a
4155 		 * bridge-tunnel header - but if we get them this way then
4156 		 * there's little point in discarding them.
4157 		 */
4158 		if (unlikely(payload->proto == cpu_to_be16(ETH_P_TDLS) ||
4159 			     payload->proto == fast_rx->control_port_protocol))
4160 			return false;
4161 	}
4162 
4163 	/* after this point, don't punt to the slowpath! */
4164 
4165 	if (rx->key && !(status->flag & RX_FLAG_MIC_STRIPPED) &&
4166 	    pskb_trim(skb, skb->len - fast_rx->icv_len))
4167 		goto drop;
4168 
4169 	if (unlikely(fast_rx->sta_notify)) {
4170 		ieee80211_sta_rx_notify(rx->sdata, hdr);
4171 		fast_rx->sta_notify = false;
4172 	}
4173 
4174 	/* statistics part of ieee80211_rx_h_sta_process() */
4175 	if (!(status->flag & RX_FLAG_NO_SIGNAL_VAL)) {
4176 		stats->last_signal = status->signal;
4177 		if (!fast_rx->uses_rss)
4178 			ewma_signal_add(&sta->rx_stats_avg.signal,
4179 					-status->signal);
4180 	}
4181 
4182 	if (status->chains) {
4183 		int i;
4184 
4185 		stats->chains = status->chains;
4186 		for (i = 0; i < ARRAY_SIZE(status->chain_signal); i++) {
4187 			int signal = status->chain_signal[i];
4188 
4189 			if (!(status->chains & BIT(i)))
4190 				continue;
4191 
4192 			stats->chain_signal_last[i] = signal;
4193 			if (!fast_rx->uses_rss)
4194 				ewma_signal_add(&sta->rx_stats_avg.chain_signal[i],
4195 						-signal);
4196 		}
4197 	}
4198 	/* end of statistics */
4199 
4200 	if (rx->key && !ieee80211_has_protected(hdr->frame_control))
4201 		goto drop;
4202 
4203 	if (status->rx_flags & IEEE80211_RX_AMSDU) {
4204 		if (__ieee80211_rx_h_amsdu(rx, snap_offs - hdrlen) !=
4205 		    RX_QUEUED)
4206 			goto drop;
4207 
4208 		return true;
4209 	}
4210 
4211 	stats->last_rx = jiffies;
4212 	stats->last_rate = sta_stats_encode_rate(status);
4213 
4214 	stats->fragments++;
4215 	stats->packets++;
4216 
4217 	/* do the header conversion - first grab the addresses */
4218 	ether_addr_copy(addrs.da, skb->data + fast_rx->da_offs);
4219 	ether_addr_copy(addrs.sa, skb->data + fast_rx->sa_offs);
4220 	/* remove the SNAP but leave the ethertype */
4221 	skb_pull(skb, snap_offs + sizeof(rfc1042_header));
4222 	/* push the addresses in front */
4223 	memcpy(skb_push(skb, sizeof(addrs)), &addrs, sizeof(addrs));
4224 
4225 	skb->dev = fast_rx->dev;
4226 
4227 	ieee80211_rx_stats(fast_rx->dev, skb->len);
4228 
4229 	/* The seqno index has the same property as needed
4230 	 * for the rx_msdu field, i.e. it is IEEE80211_NUM_TIDS
4231 	 * for non-QoS-data frames. Here we know it's a data
4232 	 * frame, so count MSDUs.
4233 	 */
4234 	u64_stats_update_begin(&stats->syncp);
4235 	stats->msdu[rx->seqno_idx]++;
4236 	stats->bytes += orig_len;
4237 	u64_stats_update_end(&stats->syncp);
4238 
4239 	if (fast_rx->internal_forward) {
4240 		struct sk_buff *xmit_skb = NULL;
4241 		bool multicast = is_multicast_ether_addr(skb->data);
4242 
4243 		if (multicast) {
4244 			xmit_skb = skb_copy(skb, GFP_ATOMIC);
4245 		} else if (sta_info_get(rx->sdata, skb->data)) {
4246 			xmit_skb = skb;
4247 			skb = NULL;
4248 		}
4249 
4250 		if (xmit_skb) {
4251 			/*
4252 			 * Send to wireless media and increase priority by 256
4253 			 * to keep the received priority instead of
4254 			 * reclassifying the frame (see cfg80211_classify8021d).
4255 			 */
4256 			xmit_skb->priority += 256;
4257 			xmit_skb->protocol = htons(ETH_P_802_3);
4258 			skb_reset_network_header(xmit_skb);
4259 			skb_reset_mac_header(xmit_skb);
4260 			dev_queue_xmit(xmit_skb);
4261 		}
4262 
4263 		if (!skb)
4264 			return true;
4265 	}
4266 
4267 	/* deliver to local stack */
4268 	skb->protocol = eth_type_trans(skb, fast_rx->dev);
4269 	memset(skb->cb, 0, sizeof(skb->cb));
4270 	if (rx->napi)
4271 		napi_gro_receive(rx->napi, skb);
4272 	else
4273 		netif_receive_skb(skb);
4274 
4275 	return true;
4276  drop:
4277 	dev_kfree_skb(skb);
4278 	stats->dropped++;
4279 	return true;
4280 }
4281 
4282 /*
4283  * This function returns whether or not the SKB
4284  * was destined for RX processing or not, which,
4285  * if consume is true, is equivalent to whether
4286  * or not the skb was consumed.
4287  */
4288 static bool ieee80211_prepare_and_rx_handle(struct ieee80211_rx_data *rx,
4289 					    struct sk_buff *skb, bool consume)
4290 {
4291 	struct ieee80211_local *local = rx->local;
4292 	struct ieee80211_sub_if_data *sdata = rx->sdata;
4293 
4294 	rx->skb = skb;
4295 
4296 	/* See if we can do fast-rx; if we have to copy we already lost,
4297 	 * so punt in that case. We should never have to deliver a data
4298 	 * frame to multiple interfaces anyway.
4299 	 *
4300 	 * We skip the ieee80211_accept_frame() call and do the necessary
4301 	 * checking inside ieee80211_invoke_fast_rx().
4302 	 */
4303 	if (consume && rx->sta) {
4304 		struct ieee80211_fast_rx *fast_rx;
4305 
4306 		fast_rx = rcu_dereference(rx->sta->fast_rx);
4307 		if (fast_rx && ieee80211_invoke_fast_rx(rx, fast_rx))
4308 			return true;
4309 	}
4310 
4311 	if (!ieee80211_accept_frame(rx))
4312 		return false;
4313 
4314 	if (!consume) {
4315 		skb = skb_copy(skb, GFP_ATOMIC);
4316 		if (!skb) {
4317 			if (net_ratelimit())
4318 				wiphy_debug(local->hw.wiphy,
4319 					"failed to copy skb for %s\n",
4320 					sdata->name);
4321 			return true;
4322 		}
4323 
4324 		rx->skb = skb;
4325 	}
4326 
4327 	ieee80211_invoke_rx_handlers(rx);
4328 	return true;
4329 }
4330 
4331 /*
4332  * This is the actual Rx frames handler. as it belongs to Rx path it must
4333  * be called with rcu_read_lock protection.
4334  */
4335 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
4336 					 struct ieee80211_sta *pubsta,
4337 					 struct sk_buff *skb,
4338 					 struct napi_struct *napi)
4339 {
4340 	struct ieee80211_local *local = hw_to_local(hw);
4341 	struct ieee80211_sub_if_data *sdata;
4342 	struct ieee80211_hdr *hdr;
4343 	__le16 fc;
4344 	struct ieee80211_rx_data rx;
4345 	struct ieee80211_sub_if_data *prev;
4346 	struct rhlist_head *tmp;
4347 	int err = 0;
4348 
4349 	fc = ((struct ieee80211_hdr *)skb->data)->frame_control;
4350 	memset(&rx, 0, sizeof(rx));
4351 	rx.skb = skb;
4352 	rx.local = local;
4353 	rx.napi = napi;
4354 
4355 	if (ieee80211_is_data(fc) || ieee80211_is_mgmt(fc))
4356 		I802_DEBUG_INC(local->dot11ReceivedFragmentCount);
4357 
4358 	if (ieee80211_is_mgmt(fc)) {
4359 		/* drop frame if too short for header */
4360 		if (skb->len < ieee80211_hdrlen(fc))
4361 			err = -ENOBUFS;
4362 		else
4363 			err = skb_linearize(skb);
4364 	} else {
4365 		err = !pskb_may_pull(skb, ieee80211_hdrlen(fc));
4366 	}
4367 
4368 	if (err) {
4369 		dev_kfree_skb(skb);
4370 		return;
4371 	}
4372 
4373 	hdr = (struct ieee80211_hdr *)skb->data;
4374 	ieee80211_parse_qos(&rx);
4375 	ieee80211_verify_alignment(&rx);
4376 
4377 	if (unlikely(ieee80211_is_probe_resp(hdr->frame_control) ||
4378 		     ieee80211_is_beacon(hdr->frame_control)))
4379 		ieee80211_scan_rx(local, skb);
4380 
4381 	if (ieee80211_is_data(fc)) {
4382 		struct sta_info *sta, *prev_sta;
4383 
4384 		if (pubsta) {
4385 			rx.sta = container_of(pubsta, struct sta_info, sta);
4386 			rx.sdata = rx.sta->sdata;
4387 			if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
4388 				return;
4389 			goto out;
4390 		}
4391 
4392 		prev_sta = NULL;
4393 
4394 		for_each_sta_info(local, hdr->addr2, sta, tmp) {
4395 			if (!prev_sta) {
4396 				prev_sta = sta;
4397 				continue;
4398 			}
4399 
4400 			rx.sta = prev_sta;
4401 			rx.sdata = prev_sta->sdata;
4402 			ieee80211_prepare_and_rx_handle(&rx, skb, false);
4403 
4404 			prev_sta = sta;
4405 		}
4406 
4407 		if (prev_sta) {
4408 			rx.sta = prev_sta;
4409 			rx.sdata = prev_sta->sdata;
4410 
4411 			if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
4412 				return;
4413 			goto out;
4414 		}
4415 	}
4416 
4417 	prev = NULL;
4418 
4419 	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
4420 		if (!ieee80211_sdata_running(sdata))
4421 			continue;
4422 
4423 		if (sdata->vif.type == NL80211_IFTYPE_MONITOR ||
4424 		    sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
4425 			continue;
4426 
4427 		/*
4428 		 * frame is destined for this interface, but if it's
4429 		 * not also for the previous one we handle that after
4430 		 * the loop to avoid copying the SKB once too much
4431 		 */
4432 
4433 		if (!prev) {
4434 			prev = sdata;
4435 			continue;
4436 		}
4437 
4438 		rx.sta = sta_info_get_bss(prev, hdr->addr2);
4439 		rx.sdata = prev;
4440 		ieee80211_prepare_and_rx_handle(&rx, skb, false);
4441 
4442 		prev = sdata;
4443 	}
4444 
4445 	if (prev) {
4446 		rx.sta = sta_info_get_bss(prev, hdr->addr2);
4447 		rx.sdata = prev;
4448 
4449 		if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
4450 			return;
4451 	}
4452 
4453  out:
4454 	dev_kfree_skb(skb);
4455 }
4456 
4457 /*
4458  * This is the receive path handler. It is called by a low level driver when an
4459  * 802.11 MPDU is received from the hardware.
4460  */
4461 void ieee80211_rx_napi(struct ieee80211_hw *hw, struct ieee80211_sta *pubsta,
4462 		       struct sk_buff *skb, struct napi_struct *napi)
4463 {
4464 	struct ieee80211_local *local = hw_to_local(hw);
4465 	struct ieee80211_rate *rate = NULL;
4466 	struct ieee80211_supported_band *sband;
4467 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
4468 
4469 	WARN_ON_ONCE(softirq_count() == 0);
4470 
4471 	if (WARN_ON(status->band >= NUM_NL80211_BANDS))
4472 		goto drop;
4473 
4474 	sband = local->hw.wiphy->bands[status->band];
4475 	if (WARN_ON(!sband))
4476 		goto drop;
4477 
4478 	/*
4479 	 * If we're suspending, it is possible although not too likely
4480 	 * that we'd be receiving frames after having already partially
4481 	 * quiesced the stack. We can't process such frames then since
4482 	 * that might, for example, cause stations to be added or other
4483 	 * driver callbacks be invoked.
4484 	 */
4485 	if (unlikely(local->quiescing || local->suspended))
4486 		goto drop;
4487 
4488 	/* We might be during a HW reconfig, prevent Rx for the same reason */
4489 	if (unlikely(local->in_reconfig))
4490 		goto drop;
4491 
4492 	/*
4493 	 * The same happens when we're not even started,
4494 	 * but that's worth a warning.
4495 	 */
4496 	if (WARN_ON(!local->started))
4497 		goto drop;
4498 
4499 	if (likely(!(status->flag & RX_FLAG_FAILED_PLCP_CRC))) {
4500 		/*
4501 		 * Validate the rate, unless a PLCP error means that
4502 		 * we probably can't have a valid rate here anyway.
4503 		 */
4504 
4505 		switch (status->encoding) {
4506 		case RX_ENC_HT:
4507 			/*
4508 			 * rate_idx is MCS index, which can be [0-76]
4509 			 * as documented on:
4510 			 *
4511 			 * http://wireless.kernel.org/en/developers/Documentation/ieee80211/802.11n
4512 			 *
4513 			 * Anything else would be some sort of driver or
4514 			 * hardware error. The driver should catch hardware
4515 			 * errors.
4516 			 */
4517 			if (WARN(status->rate_idx > 76,
4518 				 "Rate marked as an HT rate but passed "
4519 				 "status->rate_idx is not "
4520 				 "an MCS index [0-76]: %d (0x%02x)\n",
4521 				 status->rate_idx,
4522 				 status->rate_idx))
4523 				goto drop;
4524 			break;
4525 		case RX_ENC_VHT:
4526 			if (WARN_ONCE(status->rate_idx > 9 ||
4527 				      !status->nss ||
4528 				      status->nss > 8,
4529 				      "Rate marked as a VHT rate but data is invalid: MCS: %d, NSS: %d\n",
4530 				      status->rate_idx, status->nss))
4531 				goto drop;
4532 			break;
4533 		case RX_ENC_HE:
4534 			if (WARN_ONCE(status->rate_idx > 11 ||
4535 				      !status->nss ||
4536 				      status->nss > 8,
4537 				      "Rate marked as an HE rate but data is invalid: MCS: %d, NSS: %d\n",
4538 				      status->rate_idx, status->nss))
4539 				goto drop;
4540 			break;
4541 		default:
4542 			WARN_ON_ONCE(1);
4543 			/* fall through */
4544 		case RX_ENC_LEGACY:
4545 			if (WARN_ON(status->rate_idx >= sband->n_bitrates))
4546 				goto drop;
4547 			rate = &sband->bitrates[status->rate_idx];
4548 		}
4549 	}
4550 
4551 	status->rx_flags = 0;
4552 
4553 	/*
4554 	 * key references and virtual interfaces are protected using RCU
4555 	 * and this requires that we are in a read-side RCU section during
4556 	 * receive processing
4557 	 */
4558 	rcu_read_lock();
4559 
4560 	/*
4561 	 * Frames with failed FCS/PLCP checksum are not returned,
4562 	 * all other frames are returned without radiotap header
4563 	 * if it was previously present.
4564 	 * Also, frames with less than 16 bytes are dropped.
4565 	 */
4566 	skb = ieee80211_rx_monitor(local, skb, rate);
4567 	if (!skb) {
4568 		rcu_read_unlock();
4569 		return;
4570 	}
4571 
4572 	ieee80211_tpt_led_trig_rx(local,
4573 			((struct ieee80211_hdr *)skb->data)->frame_control,
4574 			skb->len);
4575 
4576 	__ieee80211_rx_handle_packet(hw, pubsta, skb, napi);
4577 
4578 	rcu_read_unlock();
4579 
4580 	return;
4581  drop:
4582 	kfree_skb(skb);
4583 }
4584 EXPORT_SYMBOL(ieee80211_rx_napi);
4585 
4586 /* This is a version of the rx handler that can be called from hard irq
4587  * context. Post the skb on the queue and schedule the tasklet */
4588 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb)
4589 {
4590 	struct ieee80211_local *local = hw_to_local(hw);
4591 
4592 	BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
4593 
4594 	skb->pkt_type = IEEE80211_RX_MSG;
4595 	skb_queue_tail(&local->skb_queue, skb);
4596 	tasklet_schedule(&local->tasklet);
4597 }
4598 EXPORT_SYMBOL(ieee80211_rx_irqsafe);
4599