text: // SPDX-License-Identifier: GPL-2.0-only
  /*
   * Copyright 2002-2005, Instant802 Networks, Inc.
   * Copyright 2005-2006, Devicescape Software, Inc.
   * Copyright 2006-2007	Jiri Benc <jbenc@suse.cz>
   * Copyright 2007-2010	Johannes Berg <johannes@sipsolutions.net>
   * Copyright 2013-2014  Intel Mobile Communications GmbH
   * Copyright(c) 2015 - 2017 Intel Deutschland GmbH
   * Copyright (C) 2018-2021 Intel Corporation
   */
  
  #include <linux/jiffies.h>
  #include <linux/slab.h>
  #include <linux/kernel.h>
  #include <linux/skbuff.h>
  #include <linux/netdevice.h>
  #include <linux/etherdevice.h>
  #include <linux/rcupdate.h>
  #include <linux/export.h>
  #include <linux/bitops.h>
  #include <net/mac80211.h>
  #include <net/ieee80211_radiotap.h>
  #include <asm/unaligned.h>
  
  #include "ieee80211_i.h"
  #include "driver-ops.h"
  #include "led.h"
  #include "mesh.h"
  #include "wep.h"
  #include "wpa.h"
  #include "tkip.h"
  #include "wme.h"
  #include "rate.h"
  
  static inline void ieee80211_rx_stats(struct net_device *dev, u32 len)
  {
  	struct pcpu_sw_netstats *tstats = this_cpu_ptr(dev->tstats);
  
  	u64_stats_update_begin(&tstats->syncp);
  	tstats->rx_packets++;
  	tstats->rx_bytes += len;
  	u64_stats_update_end(&tstats->syncp);
  }
  
  /*
   * monitor mode reception
   *
   * This function cleans up the SKB, i.e. it removes all the stuff
   * only useful for monitoring.
   */
  static struct sk_buff *ieee80211_clean_skb(struct sk_buff *skb,
  					   unsigned int present_fcs_len,
  					   unsigned int rtap_space)
  {
  	struct ieee80211_hdr *hdr;
  	unsigned int hdrlen;
  	__le16 fc;
  
  	if (present_fcs_len)
  		__pskb_trim(skb, skb->len - present_fcs_len);
  	__pskb_pull(skb, rtap_space);
  
  	hdr = (void *)skb->data;
  	fc = hdr->frame_control;
  
  	/*
  	 * Remove the HT-Control field (if present) on management
  	 * frames after we've sent the frame to monitoring. We
  	 * (currently) don't need it, and don't properly parse
  	 * frames with it present, due to the assumption of a
  	 * fixed management header length.
  	 */
  	if (likely(!ieee80211_is_mgmt(fc) || !ieee80211_has_order(fc)))
  		return skb;
  
  	hdrlen = ieee80211_hdrlen(fc);
  	hdr->frame_control &= ~cpu_to_le16(IEEE80211_FCTL_ORDER);
  
  	if (!pskb_may_pull(skb, hdrlen)) {
  		dev_kfree_skb(skb);
  		return NULL;
  	}
  
  	memmove(skb->data + IEEE80211_HT_CTL_LEN, skb->data,
  		hdrlen - IEEE80211_HT_CTL_LEN);
  	__pskb_pull(skb, IEEE80211_HT_CTL_LEN);
  
  	return skb;
  }
  
  static inline bool should_drop_frame(struct sk_buff *skb, int present_fcs_len,
  				     unsigned int rtap_space)
  {
  	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
  	struct ieee80211_hdr *hdr;
  
  	hdr = (void *)(skb->data + rtap_space);
  
  	if (status->flag & (RX_FLAG_FAILED_FCS_CRC |
  			    RX_FLAG_FAILED_PLCP_CRC |
  			    RX_FLAG_ONLY_MONITOR |
  			    RX_FLAG_NO_PSDU))
  		return true;
  
  	if (unlikely(skb->len < 16 + present_fcs_len + rtap_space))
  		return true;
  
  	if (ieee80211_is_ctl(hdr->frame_control) &&
  	    !ieee80211_is_pspoll(hdr->frame_control) &&
  	    !ieee80211_is_back_req(hdr->frame_control))
  		return true;
  
  	return false;
  }
  
  static int
  ieee80211_rx_radiotap_hdrlen(struct ieee80211_local *local,
  			     struct ieee80211_rx_status *status,
  			     struct sk_buff *skb)
  {
  	int len;
  
  	/* always present fields */
  	len = sizeof(struct ieee80211_radiotap_header) + 8;
  
  	/* allocate extra bitmaps */
  	if (status->chains)
  		len += 4 * hweight8(status->chains);
  	/* vendor presence bitmap */
  	if (status->flag & RX_FLAG_RADIOTAP_VENDOR_DATA)
  		len += 4;
  
  	if (ieee80211_have_rx_timestamp(status)) {
  		len = ALIGN(len, 8);
  		len += 8;
  	}
  	if (ieee80211_hw_check(&local->hw, SIGNAL_DBM))
  		len += 1;
  
  	/* antenna field, if we don't have per-chain info */
  	if (!status->chains)
  		len += 1;
  
  	/* padding for RX_FLAGS if necessary */
  	len = ALIGN(len, 2);
  
  	if (status->encoding == RX_ENC_HT) /* HT info */
  		len += 3;
  
  	if (status->flag & RX_FLAG_AMPDU_DETAILS) {
  		len = ALIGN(len, 4);
  		len += 8;
  	}
  
  	if (status->encoding == RX_ENC_VHT) {
  		len = ALIGN(len, 2);
  		len += 12;
  	}
  
  	if (local->hw.radiotap_timestamp.units_pos >= 0) {
  		len = ALIGN(len, 8);
  		len += 12;
  	}
  
  	if (status->encoding == RX_ENC_HE &&
  	    status->flag & RX_FLAG_RADIOTAP_HE) {
  		len = ALIGN(len, 2);
  		len += 12;
  		BUILD_BUG_ON(sizeof(struct ieee80211_radiotap_he) != 12);
  	}
  
  	if (status->encoding == RX_ENC_HE &&
  	    status->flag & RX_FLAG_RADIOTAP_HE_MU) {
  		len = ALIGN(len, 2);
  		len += 12;
  		BUILD_BUG_ON(sizeof(struct ieee80211_radiotap_he_mu) != 12);
  	}
  
  	if (status->flag & RX_FLAG_NO_PSDU)
  		len += 1;
  
  	if (status->flag & RX_FLAG_RADIOTAP_LSIG) {
  		len = ALIGN(len, 2);
  		len += 4;
  		BUILD_BUG_ON(sizeof(struct ieee80211_radiotap_lsig) != 4);
  	}
  
  	if (status->chains) {
  		/* antenna and antenna signal fields */
  		len += 2 * hweight8(status->chains);
  	}
  
  	if (status->flag & RX_FLAG_RADIOTAP_VENDOR_DATA) {
  		struct ieee80211_vendor_radiotap *rtap;
  		int vendor_data_offset = 0;
  
  		/*
  		 * The position to look at depends on the existence (or non-
  		 * existence) of other elements, so take that into account...
  		 */
  		if (status->flag & RX_FLAG_RADIOTAP_HE)
  			vendor_data_offset +=
  				sizeof(struct ieee80211_radiotap_he);
  		if (status->flag & RX_FLAG_RADIOTAP_HE_MU)
  			vendor_data_offset +=
  				sizeof(struct ieee80211_radiotap_he_mu);
  		if (status->flag & RX_FLAG_RADIOTAP_LSIG)
  			vendor_data_offset +=
  				sizeof(struct ieee80211_radiotap_lsig);
  
  		rtap = (void *)&skb->data[vendor_data_offset];
  
  		/* alignment for fixed 6-byte vendor data header */
  		len = ALIGN(len, 2);
  		/* vendor data header */
  		len += 6;
  		if (WARN_ON(rtap->align == 0))
  			rtap->align = 1;
  		len = ALIGN(len, rtap->align);
  		len += rtap->len + rtap->pad;
  	}
  
  	return len;
  }
  
  static void ieee80211_handle_mu_mimo_mon(struct ieee80211_sub_if_data *sdata,
  					 struct sk_buff *skb,
  					 int rtap_space)
  {
  	struct {
  		struct ieee80211_hdr_3addr hdr;
  		u8 category;
  		u8 action_code;
  	} __packed __aligned(2) action;
  
  	if (!sdata)
  		return;
  
  	BUILD_BUG_ON(sizeof(action) != IEEE80211_MIN_ACTION_SIZE + 1);
  
  	if (skb->len < rtap_space + sizeof(action) +
  		       VHT_MUMIMO_GROUPS_DATA_LEN)
  		return;
  
  	if (!is_valid_ether_addr(sdata->u.mntr.mu_follow_addr))
  		return;
  
  	skb_copy_bits(skb, rtap_space, &action, sizeof(action));
  
  	if (!ieee80211_is_action(action.hdr.frame_control))
  		return;
  
  	if (action.category != WLAN_CATEGORY_VHT)
  		return;
  
  	if (action.action_code != WLAN_VHT_ACTION_GROUPID_MGMT)
  		return;
  
  	if (!ether_addr_equal(action.hdr.addr1, sdata->u.mntr.mu_follow_addr))
  		return;
  
  	skb = skb_copy(skb, GFP_ATOMIC);
  	if (!skb)
  		return;
  
  	skb_queue_tail(&sdata->skb_queue, skb);
  	ieee80211_queue_work(&sdata->local->hw, &sdata->work);
  }
  
  /*
   * ieee80211_add_rx_radiotap_header - add radiotap header
   *
   * add a radiotap header containing all the fields which the hardware provided.
   */
  static void
  ieee80211_add_rx_radiotap_header(struct ieee80211_local *local,
  				 struct sk_buff *skb,
  				 struct ieee80211_rate *rate,
  				 int rtap_len, bool has_fcs)
  {
  	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
  	struct ieee80211_radiotap_header *rthdr;
  	unsigned char *pos;
  	__le32 *it_present;
  	u32 it_present_val;
  	u16 rx_flags = 0;
  	u16 channel_flags = 0;
  	int mpdulen, chain;
  	unsigned long chains = status->chains;
  	struct ieee80211_vendor_radiotap rtap = {};
  	struct ieee80211_radiotap_he he = {};
  	struct ieee80211_radiotap_he_mu he_mu = {};
  	struct ieee80211_radiotap_lsig lsig = {};
  
  	if (status->flag & RX_FLAG_RADIOTAP_HE) {
  		he = *(struct ieee80211_radiotap_he *)skb->data;
  		skb_pull(skb, sizeof(he));
  		WARN_ON_ONCE(status->encoding != RX_ENC_HE);
  	}
  
  	if (status->flag & RX_FLAG_RADIOTAP_HE_MU) {
  		he_mu = *(struct ieee80211_radiotap_he_mu *)skb->data;
  		skb_pull(skb, sizeof(he_mu));
  	}
  
  	if (status->flag & RX_FLAG_RADIOTAP_LSIG) {
  		lsig = *(struct ieee80211_radiotap_lsig *)skb->data;
  		skb_pull(skb, sizeof(lsig));
  	}
  
  	if (status->flag & RX_FLAG_RADIOTAP_VENDOR_DATA) {
  		rtap = *(struct ieee80211_vendor_radiotap *)skb->data;
  		/* rtap.len and rtap.pad are undone immediately */
  		skb_pull(skb, sizeof(rtap) + rtap.len + rtap.pad);
  	}
  
  	mpdulen = skb->len;
  	if (!(has_fcs && ieee80211_hw_check(&local->hw, RX_INCLUDES_FCS)))
  		mpdulen += FCS_LEN;
  
  	rthdr = skb_push(skb, rtap_len);
  	memset(rthdr, 0, rtap_len - rtap.len - rtap.pad);
  	it_present = &rthdr->it_present;
  
  	/* radiotap header, set always present flags */
  	rthdr->it_len = cpu_to_le16(rtap_len);
  	it_present_val = BIT(IEEE80211_RADIOTAP_FLAGS) |
  			 BIT(IEEE80211_RADIOTAP_CHANNEL) |
  			 BIT(IEEE80211_RADIOTAP_RX_FLAGS);
  
  	if (!status->chains)
  		it_present_val |= BIT(IEEE80211_RADIOTAP_ANTENNA);
  
  	for_each_set_bit(chain, &chains, IEEE80211_MAX_CHAINS) {
  		it_present_val |=
  			BIT(IEEE80211_RADIOTAP_EXT) |
  			BIT(IEEE80211_RADIOTAP_RADIOTAP_NAMESPACE);
  		put_unaligned_le32(it_present_val, it_present);
  		it_present++;
  		it_present_val = BIT(IEEE80211_RADIOTAP_ANTENNA) |
  				 BIT(IEEE80211_RADIOTAP_DBM_ANTSIGNAL);
  	}
  
  	if (status->flag & RX_FLAG_RADIOTAP_VENDOR_DATA) {
  		it_present_val |= BIT(IEEE80211_RADIOTAP_VENDOR_NAMESPACE) |
  				  BIT(IEEE80211_RADIOTAP_EXT);
  		put_unaligned_le32(it_present_val, it_present);
  		it_present++;
  		it_present_val = rtap.present;
  	}
  
  	put_unaligned_le32(it_present_val, it_present);
  
  	pos = (void *)(it_present + 1);
  
  	/* the order of the following fields is important */
  
  	/* IEEE80211_RADIOTAP_TSFT */
  	if (ieee80211_have_rx_timestamp(status)) {
  		/* padding */
  		while ((pos - (u8 *)rthdr) & 7)
  			*pos++ = 0;
  		put_unaligned_le64(
  			ieee80211_calculate_rx_timestamp(local, status,
  							 mpdulen, 0),
  			pos);
  		rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_TSFT);
  		pos += 8;
  	}
  
  	/* IEEE80211_RADIOTAP_FLAGS */
  	if (has_fcs && ieee80211_hw_check(&local->hw, RX_INCLUDES_FCS))
  		*pos |= IEEE80211_RADIOTAP_F_FCS;
  	if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
  		*pos |= IEEE80211_RADIOTAP_F_BADFCS;
  	if (status->enc_flags & RX_ENC_FLAG_SHORTPRE)
  		*pos |= IEEE80211_RADIOTAP_F_SHORTPRE;
  	pos++;
  
  	/* IEEE80211_RADIOTAP_RATE */
  	if (!rate || status->encoding != RX_ENC_LEGACY) {
  		/*
  		 * Without rate information don't add it. If we have,
  		 * MCS information is a separate field in radiotap,
  		 * added below. The byte here is needed as padding
  		 * for the channel though, so initialise it to 0.
  		 */
  		*pos = 0;
  	} else {
  		int shift = 0;
  		rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
  		if (status->bw == RATE_INFO_BW_10)
  			shift = 1;
  		else if (status->bw == RATE_INFO_BW_5)
  			shift = 2;
  		*pos = DIV_ROUND_UP(rate->bitrate, 5 * (1 << shift));
  	}
  	pos++;
  
  	/* IEEE80211_RADIOTAP_CHANNEL */
  	/* TODO: frequency offset in KHz */
  	put_unaligned_le16(status->freq, pos);
  	pos += 2;
  	if (status->bw == RATE_INFO_BW_10)
  		channel_flags |= IEEE80211_CHAN_HALF;
  	else if (status->bw == RATE_INFO_BW_5)
  		channel_flags |= IEEE80211_CHAN_QUARTER;
  
  	if (status->band == NL80211_BAND_5GHZ ||
  	    status->band == NL80211_BAND_6GHZ)
  		channel_flags |= IEEE80211_CHAN_OFDM | IEEE80211_CHAN_5GHZ;
  	else if (status->encoding != RX_ENC_LEGACY)
  		channel_flags |= IEEE80211_CHAN_DYN | IEEE80211_CHAN_2GHZ;
  	else if (rate && rate->flags & IEEE80211_RATE_ERP_G)
  		channel_flags |= IEEE80211_CHAN_OFDM | IEEE80211_CHAN_2GHZ;
  	else if (rate)
  		channel_flags |= IEEE80211_CHAN_CCK | IEEE80211_CHAN_2GHZ;
  	else
  		channel_flags |= IEEE80211_CHAN_2GHZ;
  	put_unaligned_le16(channel_flags, pos);
  	pos += 2;
  
  	/* IEEE80211_RADIOTAP_DBM_ANTSIGNAL */
  	if (ieee80211_hw_check(&local->hw, SIGNAL_DBM) &&
  	    !(status->flag & RX_FLAG_NO_SIGNAL_VAL)) {
  		*pos = status->signal;
  		rthdr->it_present |=
  			cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTSIGNAL);
  		pos++;
  	}
  
  	/* IEEE80211_RADIOTAP_LOCK_QUALITY is missing */
  
  	if (!status->chains) {
  		/* IEEE80211_RADIOTAP_ANTENNA */
  		*pos = status->antenna;
  		pos++;
  	}
  
  	/* IEEE80211_RADIOTAP_DB_ANTNOISE is not used */
  
  	/* IEEE80211_RADIOTAP_RX_FLAGS */
  	/* ensure 2 byte alignment for the 2 byte field as required */
  	if ((pos - (u8 *)rthdr) & 1)
  		*pos++ = 0;
  	if (status->flag & RX_FLAG_FAILED_PLCP_CRC)
  		rx_flags |= IEEE80211_RADIOTAP_F_RX_BADPLCP;
  	put_unaligned_le16(rx_flags, pos);
  	pos += 2;
  
  	if (status->encoding == RX_ENC_HT) {
  		unsigned int stbc;
  
  		rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_MCS);
  		*pos++ = local->hw.radiotap_mcs_details;
  		*pos = 0;
  		if (status->enc_flags & RX_ENC_FLAG_SHORT_GI)
  			*pos |= IEEE80211_RADIOTAP_MCS_SGI;
  		if (status->bw == RATE_INFO_BW_40)
  			*pos |= IEEE80211_RADIOTAP_MCS_BW_40;
  		if (status->enc_flags & RX_ENC_FLAG_HT_GF)
  			*pos |= IEEE80211_RADIOTAP_MCS_FMT_GF;
  		if (status->enc_flags & RX_ENC_FLAG_LDPC)
  			*pos |= IEEE80211_RADIOTAP_MCS_FEC_LDPC;
  		stbc = (status->enc_flags & RX_ENC_FLAG_STBC_MASK) >> RX_ENC_FLAG_STBC_SHIFT;
  		*pos |= stbc << IEEE80211_RADIOTAP_MCS_STBC_SHIFT;
  		pos++;
  		*pos++ = status->rate_idx;
  	}
  
  	if (status->flag & RX_FLAG_AMPDU_DETAILS) {
  		u16 flags = 0;
  
  		/* ensure 4 byte alignment */
  		while ((pos - (u8 *)rthdr) & 3)
  			pos++;
  		rthdr->it_present |=
  			cpu_to_le32(1 << IEEE80211_RADIOTAP_AMPDU_STATUS);
  		put_unaligned_le32(status->ampdu_reference, pos);
  		pos += 4;
  		if (status->flag & RX_FLAG_AMPDU_LAST_KNOWN)
  			flags |= IEEE80211_RADIOTAP_AMPDU_LAST_KNOWN;
  		if (status->flag & RX_FLAG_AMPDU_IS_LAST)
  			flags |= IEEE80211_RADIOTAP_AMPDU_IS_LAST;
  		if (status->flag & RX_FLAG_AMPDU_DELIM_CRC_ERROR)
  			flags |= IEEE80211_RADIOTAP_AMPDU_DELIM_CRC_ERR;
  		if (status->flag & RX_FLAG_AMPDU_DELIM_CRC_KNOWN)
  			flags |= IEEE80211_RADIOTAP_AMPDU_DELIM_CRC_KNOWN;
  		if (status->flag & RX_FLAG_AMPDU_EOF_BIT_KNOWN)
  			flags |= IEEE80211_RADIOTAP_AMPDU_EOF_KNOWN;
  		if (status->flag & RX_FLAG_AMPDU_EOF_BIT)
  			flags |= IEEE80211_RADIOTAP_AMPDU_EOF;
  		put_unaligned_le16(flags, pos);
  		pos += 2;
  		if (status->flag & RX_FLAG_AMPDU_DELIM_CRC_KNOWN)
  			*pos++ = status->ampdu_delimiter_crc;
  		else
  			*pos++ = 0;
  		*pos++ = 0;
  	}
  
  	if (status->encoding == RX_ENC_VHT) {
  		u16 known = local->hw.radiotap_vht_details;
  
  		rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_VHT);
  		put_unaligned_le16(known, pos);
  		pos += 2;
  		/* flags */
  		if (status->enc_flags & RX_ENC_FLAG_SHORT_GI)
  			*pos |= IEEE80211_RADIOTAP_VHT_FLAG_SGI;
  		/* in VHT, STBC is binary */
  		if (status->enc_flags & RX_ENC_FLAG_STBC_MASK)
  			*pos |= IEEE80211_RADIOTAP_VHT_FLAG_STBC;
  		if (status->enc_flags & RX_ENC_FLAG_BF)
  			*pos |= IEEE80211_RADIOTAP_VHT_FLAG_BEAMFORMED;
  		pos++;
  		/* bandwidth */
  		switch (status->bw) {
  		case RATE_INFO_BW_80:
  			*pos++ = 4;
  			break;
  		case RATE_INFO_BW_160:
  			*pos++ = 11;
  			break;
  		case RATE_INFO_BW_40:
  			*pos++ = 1;
  			break;
  		default:
  			*pos++ = 0;
  		}
  		/* MCS/NSS */
  		*pos = (status->rate_idx << 4) | status->nss;
  		pos += 4;
  		/* coding field */
  		if (status->enc_flags & RX_ENC_FLAG_LDPC)
  			*pos |= IEEE80211_RADIOTAP_CODING_LDPC_USER0;
  		pos++;
  		/* group ID */
  		pos++;
  		/* partial_aid */
  		pos += 2;
  	}
  
  	if (local->hw.radiotap_timestamp.units_pos >= 0) {
  		u16 accuracy = 0;
  		u8 flags = IEEE80211_RADIOTAP_TIMESTAMP_FLAG_32BIT;
  
  		rthdr->it_present |=
  			cpu_to_le32(1 << IEEE80211_RADIOTAP_TIMESTAMP);
  
  		/* ensure 8 byte alignment */
  		while ((pos - (u8 *)rthdr) & 7)
  			pos++;
  
  		put_unaligned_le64(status->device_timestamp, pos);
  		pos += sizeof(u64);
  
  		if (local->hw.radiotap_timestamp.accuracy >= 0) {
  			accuracy = local->hw.radiotap_timestamp.accuracy;
  			flags |= IEEE80211_RADIOTAP_TIMESTAMP_FLAG_ACCURACY;
  		}
  		put_unaligned_le16(accuracy, pos);
  		pos += sizeof(u16);
  
  		*pos++ = local->hw.radiotap_timestamp.units_pos;
  		*pos++ = flags;
  	}
  
  	if (status->encoding == RX_ENC_HE &&
  	    status->flag & RX_FLAG_RADIOTAP_HE) {
  #define HE_PREP(f, val)	le16_encode_bits(val, IEEE80211_RADIOTAP_HE_##f)
  
  		if (status->enc_flags & RX_ENC_FLAG_STBC_MASK) {
  			he.data6 |= HE_PREP(DATA6_NSTS,
  					    FIELD_GET(RX_ENC_FLAG_STBC_MASK,
  						      status->enc_flags));
  			he.data3 |= HE_PREP(DATA3_STBC, 1);
  		} else {
  			he.data6 |= HE_PREP(DATA6_NSTS, status->nss);
  		}
  
  #define CHECK_GI(s) \
  	BUILD_BUG_ON(IEEE80211_RADIOTAP_HE_DATA5_GI_##s != \
  		     (int)NL80211_RATE_INFO_HE_GI_##s)
  
  		CHECK_GI(0_8);
  		CHECK_GI(1_6);
  		CHECK_GI(3_2);
  
  		he.data3 |= HE_PREP(DATA3_DATA_MCS, status->rate_idx);
  		he.data3 |= HE_PREP(DATA3_DATA_DCM, status->he_dcm);
  		he.data3 |= HE_PREP(DATA3_CODING,
  				    !!(status->enc_flags & RX_ENC_FLAG_LDPC));
  
  		he.data5 |= HE_PREP(DATA5_GI, status->he_gi);
  
  		switch (status->bw) {
  		case RATE_INFO_BW_20:
  			he.data5 |= HE_PREP(DATA5_DATA_BW_RU_ALLOC,
  					    IEEE80211_RADIOTAP_HE_DATA5_DATA_BW_RU_ALLOC_20MHZ);
  			break;
  		case RATE_INFO_BW_40:
  			he.data5 |= HE_PREP(DATA5_DATA_BW_RU_ALLOC,
  					    IEEE80211_RADIOTAP_HE_DATA5_DATA_BW_RU_ALLOC_40MHZ);
  			break;
  		case RATE_INFO_BW_80:
  			he.data5 |= HE_PREP(DATA5_DATA_BW_RU_ALLOC,
  					    IEEE80211_RADIOTAP_HE_DATA5_DATA_BW_RU_ALLOC_80MHZ);
  			break;
  		case RATE_INFO_BW_160:
  			he.data5 |= HE_PREP(DATA5_DATA_BW_RU_ALLOC,
  					    IEEE80211_RADIOTAP_HE_DATA5_DATA_BW_RU_ALLOC_160MHZ);
  			break;
  		case RATE_INFO_BW_HE_RU:
  #define CHECK_RU_ALLOC(s) \
  	BUILD_BUG_ON(IEEE80211_RADIOTAP_HE_DATA5_DATA_BW_RU_ALLOC_##s##T != \
  		     NL80211_RATE_INFO_HE_RU_ALLOC_##s + 4)
  
  			CHECK_RU_ALLOC(26);
  			CHECK_RU_ALLOC(52);
  			CHECK_RU_ALLOC(106);
  			CHECK_RU_ALLOC(242);
  			CHECK_RU_ALLOC(484);
  			CHECK_RU_ALLOC(996);
  			CHECK_RU_ALLOC(2x996);
  
  			he.data5 |= HE_PREP(DATA5_DATA_BW_RU_ALLOC,
  					    status->he_ru + 4);
  			break;
  		default:
  			WARN_ONCE(1, "Invalid SU BW %d\n", status->bw);
  		}
  
  		/* ensure 2 byte alignment */
  		while ((pos - (u8 *)rthdr) & 1)
  			pos++;
  		rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_HE);
  		memcpy(pos, &he, sizeof(he));
  		pos += sizeof(he);
  	}
  
  	if (status->encoding == RX_ENC_HE &&
  	    status->flag & RX_FLAG_RADIOTAP_HE_MU) {
  		/* ensure 2 byte alignment */
  		while ((pos - (u8 *)rthdr) & 1)
  			pos++;
  		rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_HE_MU);
  		memcpy(pos, &he_mu, sizeof(he_mu));
  		pos += sizeof(he_mu);
  	}
  
  	if (status->flag & RX_FLAG_NO_PSDU) {
  		rthdr->it_present |=
  			cpu_to_le32(1 << IEEE80211_RADIOTAP_ZERO_LEN_PSDU);
  		*pos++ = status->zero_length_psdu_type;
  	}
  
  	if (status->flag & RX_FLAG_RADIOTAP_LSIG) {
  		/* ensure 2 byte alignment */
  		while ((pos - (u8 *)rthdr) & 1)
  			pos++;
  		rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_LSIG);
  		memcpy(pos, &lsig, sizeof(lsig));
  		pos += sizeof(lsig);
  	}
  
  	for_each_set_bit(chain, &chains, IEEE80211_MAX_CHAINS) {
  		*pos++ = status->chain_signal[chain];
  		*pos++ = chain;
  	}
  
  	if (status->flag & RX_FLAG_RADIOTAP_VENDOR_DATA) {
  		/* ensure 2 byte alignment for the vendor field as required */
  		if ((pos - (u8 *)rthdr) & 1)
  			*pos++ = 0;
  		*pos++ = rtap.oui[0];
  		*pos++ = rtap.oui[1];
  		*pos++ = rtap.oui[2];
  		*pos++ = rtap.subns;
  		put_unaligned_le16(rtap.len, pos);
  		pos += 2;
  		/* align the actual payload as requested */
  		while ((pos - (u8 *)rthdr) & (rtap.align - 1))
  			*pos++ = 0;
  		/* data (and possible padding) already follows */
  	}
  }
  
  static struct sk_buff *
  ieee80211_make_monitor_skb(struct ieee80211_local *local,
  			   struct sk_buff **origskb,
  			   struct ieee80211_rate *rate,
  			   int rtap_space, bool use_origskb)
  {
  	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(*origskb);
  	int rt_hdrlen, needed_headroom;
  	struct sk_buff *skb;
  
  	/* room for the radiotap header based on driver features */
  	rt_hdrlen = ieee80211_rx_radiotap_hdrlen(local, status, *origskb);
  	needed_headroom = rt_hdrlen - rtap_space;
  
  	if (use_origskb) {
  		/* only need to expand headroom if necessary */
  		skb = *origskb;
  		*origskb = NULL;
  
  		/*
  		 * This shouldn't trigger often because most devices have an
  		 * RX header they pull before we get here, and that should
  		 * be big enough for our radiotap information. We should
  		 * probably export the length to drivers so that we can have
  		 * them allocate enough headroom to start with.
  		 */
  		if (skb_headroom(skb) < needed_headroom &&
  		    pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC)) {
  			dev_kfree_skb(skb);
  			return NULL;
  		}
  	} else {
  		/*
  		 * Need to make a copy and possibly remove radiotap header
  		 * and FCS from the original.
  		 */
  		skb = skb_copy_expand(*origskb, needed_headroom, 0, GFP_ATOMIC);
  
  		if (!skb)
  			return NULL;
  	}
  
  	/* prepend radiotap information */
  	ieee80211_add_rx_radiotap_header(local, skb, rate, rt_hdrlen, true);
  
  	skb_reset_mac_header(skb);
  	skb->ip_summed = CHECKSUM_UNNECESSARY;
  	skb->pkt_type = PACKET_OTHERHOST;
  	skb->protocol = htons(ETH_P_802_2);
  
  	return skb;
  }
  
  /*
   * This function copies a received frame to all monitor interfaces and
   * returns a cleaned-up SKB that no longer includes the FCS nor the
   * radiotap header the driver might have added.
   */
  static struct sk_buff *
  ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb,
  		     struct ieee80211_rate *rate)
  {
  	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(origskb);
  	struct ieee80211_sub_if_data *sdata;
  	struct sk_buff *monskb = NULL;
  	int present_fcs_len = 0;
  	unsigned int rtap_space = 0;
  	struct ieee80211_sub_if_data *monitor_sdata =
  		rcu_dereference(local->monitor_sdata);
  	bool only_monitor = false;
  	unsigned int min_head_len;
  
  	if (status->flag & RX_FLAG_RADIOTAP_HE)
  		rtap_space += sizeof(struct ieee80211_radiotap_he);
  
  	if (status->flag & RX_FLAG_RADIOTAP_HE_MU)
  		rtap_space += sizeof(struct ieee80211_radiotap_he_mu);
  
  	if (status->flag & RX_FLAG_RADIOTAP_LSIG)
  		rtap_space += sizeof(struct ieee80211_radiotap_lsig);
  
  	if (unlikely(status->flag & RX_FLAG_RADIOTAP_VENDOR_DATA)) {
  		struct ieee80211_vendor_radiotap *rtap =
  			(void *)(origskb->data + rtap_space);
  
  		rtap_space += sizeof(*rtap) + rtap->len + rtap->pad;
  	}
  
  	min_head_len = rtap_space;
  
  	/*
  	 * First, we may need to make a copy of the skb because
  	 *  (1) we need to modify it for radiotap (if not present), and
  	 *  (2) the other RX handlers will modify the skb we got.
  	 *
  	 * We don't need to, of course, if we aren't going to return
  	 * the SKB because it has a bad FCS/PLCP checksum.
  	 */
  
  	if (!(status->flag & RX_FLAG_NO_PSDU)) {
  		if (ieee80211_hw_check(&local->hw, RX_INCLUDES_FCS)) {
  			if (unlikely(origskb->len <= FCS_LEN + rtap_space)) {
  				/* driver bug */
  				WARN_ON(1);
  				dev_kfree_skb(origskb);
  				return NULL;
  			}
  			present_fcs_len = FCS_LEN;
  		}
  
  		/* also consider the hdr->frame_control */
  		min_head_len += 2;
  	}
  
  	/* ensure that the expected data elements are in skb head */
  	if (!pskb_may_pull(origskb, min_head_len)) {
  		dev_kfree_skb(origskb);
  		return NULL;
  	}
  
  	only_monitor = should_drop_frame(origskb, present_fcs_len, rtap_space);
  
  	if (!local->monitors || (status->flag & RX_FLAG_SKIP_MONITOR)) {
  		if (only_monitor) {
  			dev_kfree_skb(origskb);
  			return NULL;
  		}
  
  		return ieee80211_clean_skb(origskb, present_fcs_len,
  					   rtap_space);
  	}
  
  	ieee80211_handle_mu_mimo_mon(monitor_sdata, origskb, rtap_space);
  
  	list_for_each_entry_rcu(sdata, &local->mon_list, u.mntr.list) {
  		bool last_monitor = list_is_last(&sdata->u.mntr.list,
  						 &local->mon_list);
  
  		if (!monskb)
  			monskb = ieee80211_make_monitor_skb(local, &origskb,
  							    rate, rtap_space,
  							    only_monitor &&
  							    last_monitor);
  
  		if (monskb) {
  			struct sk_buff *skb;
  
  			if (last_monitor) {
  				skb = monskb;
  				monskb = NULL;
  			} else {
  				skb = skb_clone(monskb, GFP_ATOMIC);
  			}
  
  			if (skb) {
  				skb->dev = sdata->dev;
  				ieee80211_rx_stats(skb->dev, skb->len);
  				netif_receive_skb(skb);
  			}
  		}
  
  		if (last_monitor)
  			break;
  	}
  
  	/* this happens if last_monitor was erroneously false */
  	dev_kfree_skb(monskb);
  
  	/* ditto */
  	if (!origskb)
  		return NULL;
  
  	return ieee80211_clean_skb(origskb, present_fcs_len, rtap_space);
  }
  
  static void ieee80211_parse_qos(struct ieee80211_rx_data *rx)
  {
  	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
  	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
  	int tid, seqno_idx, security_idx;
  
  	/* does the frame have a qos control field? */
  	if (ieee80211_is_data_qos(hdr->frame_control)) {
  		u8 *qc = ieee80211_get_qos_ctl(hdr);
  		/* frame has qos control */
  		tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
  		if (*qc & IEEE80211_QOS_CTL_A_MSDU_PRESENT)
  			status->rx_flags |= IEEE80211_RX_AMSDU;
  
  		seqno_idx = tid;
  		security_idx = tid;
  	} else {
  		/*
  		 * IEEE 802.11-2007, 7.1.3.4.1 ("Sequence Number field"):
  		 *
  		 *	Sequence numbers for management frames, QoS data
  		 *	frames with a broadcast/multicast address in the
  		 *	Address 1 field, and all non-QoS data frames sent
  		 *	by QoS STAs are assigned using an additional single
  		 *	modulo-4096 counter, [...]
  		 *
  		 * We also use that counter for non-QoS STAs.
  		 */
  		seqno_idx = IEEE80211_NUM_TIDS;
  		security_idx = 0;
  		if (ieee80211_is_mgmt(hdr->frame_control))
  			security_idx = IEEE80211_NUM_TIDS;
  		tid = 0;
  	}
  
  	rx->seqno_idx = seqno_idx;
  	rx->security_idx = security_idx;
  	/* Set skb->priority to 1d tag if highest order bit of TID is not set.
  	 * For now, set skb->priority to 0 for other cases. */
  	rx->skb->priority = (tid > 7) ? 0 : tid;
  }
  
  /**
   * DOC: Packet alignment
   *
   * Drivers always need to pass packets that are aligned to two-byte boundaries
   * to the stack.
   *
   * Additionally, should, if possible, align the payload data in a way that
   * guarantees that the contained IP header is aligned to a four-byte
   * boundary. In the case of regular frames, this simply means aligning the
   * payload to a four-byte boundary (because either the IP header is directly
   * contained, or IV/RFC1042 headers that have a length divisible by four are
   * in front of it).  If the payload data is not properly aligned and the
   * architecture doesn't support efficient unaligned operations, mac80211
   * will align the data.
   *
   * With A-MSDU frames, however, the payload data address must yield two modulo
   * four because there are 14-byte 802.3 headers within the A-MSDU frames that
   * push the IP header further back to a multiple of four again. Thankfully, the
   * specs were sane enough this time around to require padding each A-MSDU
   * subframe to a length that is a multiple of four.
   *
   * Padding like Atheros hardware adds which is between the 802.11 header and
   * the payload is not supported, the driver is required to move the 802.11
   * header to be directly in front of the payload in that case.
   */
  static void ieee80211_verify_alignment(struct ieee80211_rx_data *rx)
  {
  #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
  	WARN_ON_ONCE((unsigned long)rx->skb->data & 1);
  #endif
  }
  
  
  /* rx handlers */
  
  static int ieee80211_is_unicast_robust_mgmt_frame(struct sk_buff *skb)
  {
  	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
  
  	if (is_multicast_ether_addr(hdr->addr1))
  		return 0;
  
  	return ieee80211_is_robust_mgmt_frame(skb);
  }
  
  
  static int ieee80211_is_multicast_robust_mgmt_frame(struct sk_buff *skb)
  {
  	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
  
  	if (!is_multicast_ether_addr(hdr->addr1))
  		return 0;
  
  	return ieee80211_is_robust_mgmt_frame(skb);
  }
  
  
  /* Get the BIP key index from MMIE; return -1 if this is not a BIP frame */
  static int ieee80211_get_mmie_keyidx(struct sk_buff *skb)
  {
  	struct ieee80211_mgmt *hdr = (struct ieee80211_mgmt *) skb->data;
  	struct ieee80211_mmie *mmie;
  	struct ieee80211_mmie_16 *mmie16;
  
  	if (skb->len < 24 + sizeof(*mmie) || !is_multicast_ether_addr(hdr->da))
  		return -1;
  
  	if (!ieee80211_is_robust_mgmt_frame(skb) &&
  	    !ieee80211_is_beacon(hdr->frame_control))
  		return -1; /* not a robust management frame */
  
  	mmie = (struct ieee80211_mmie *)
  		(skb->data + skb->len - sizeof(*mmie));
  	if (mmie->element_id == WLAN_EID_MMIE &&
  	    mmie->length == sizeof(*mmie) - 2)
  		return le16_to_cpu(mmie->key_id);
  
  	mmie16 = (struct ieee80211_mmie_16 *)
  		(skb->data + skb->len - sizeof(*mmie16));
  	if (skb->len >= 24 + sizeof(*mmie16) &&
  	    mmie16->element_id == WLAN_EID_MMIE &&
  	    mmie16->length == sizeof(*mmie16) - 2)
  		return le16_to_cpu(mmie16->key_id);
  
  	return -1;
  }
  
  static int ieee80211_get_keyid(struct sk_buff *skb,
  			       const struct ieee80211_cipher_scheme *cs)
  {
  	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
  	__le16 fc;
  	int hdrlen;
  	int minlen;
  	u8 key_idx_off;
  	u8 key_idx_shift;
  	u8 keyid;
  
  	fc = hdr->frame_control;
  	hdrlen = ieee80211_hdrlen(fc);
  
  	if (cs) {
  		minlen = hdrlen + cs->hdr_len;
  		key_idx_off = hdrlen + cs->key_idx_off;
  		key_idx_shift = cs->key_idx_shift;
  	} else {
  		/* WEP, TKIP, CCMP and GCMP */
  		minlen = hdrlen + IEEE80211_WEP_IV_LEN;
  		key_idx_off = hdrlen + 3;
  		key_idx_shift = 6;
  	}
  
  	if (unlikely(skb->len < minlen))
  		return -EINVAL;
  
  	skb_copy_bits(skb, key_idx_off, &keyid, 1);
  
  	if (cs)
  		keyid &= cs->key_idx_mask;
  	keyid >>= key_idx_shift;
  
  	/* cs could use more than the usual two bits for the keyid */
  	if (unlikely(keyid >= NUM_DEFAULT_KEYS))
  		return -EINVAL;
  
  	return keyid;
  }
  
  static ieee80211_rx_result ieee80211_rx_mesh_check(struct ieee80211_rx_data *rx)
  {
  	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
  	char *dev_addr = rx->sdata->vif.addr;
  
  	if (ieee80211_is_data(hdr->frame_control)) {
  		if (is_multicast_ether_addr(hdr->addr1)) {
  			if (ieee80211_has_tods(hdr->frame_control) ||
  			    !ieee80211_has_fromds(hdr->frame_control))
  				return RX_DROP_MONITOR;
  			if (ether_addr_equal(hdr->addr3, dev_addr))
  				return RX_DROP_MONITOR;
  		} else {
  			if (!ieee80211_has_a4(hdr->frame_control))
  				return RX_DROP_MONITOR;
  			if (ether_addr_equal(hdr->addr4, dev_addr))
  				return RX_DROP_MONITOR;
  		}
  	}
  
  	/* If there is not an established peer link and this is not a peer link
  	 * establisment frame, beacon or probe, drop the frame.
  	 */
  
  	if (!rx->sta || sta_plink_state(rx->sta) != NL80211_PLINK_ESTAB) {
  		struct ieee80211_mgmt *mgmt;
  
  		if (!ieee80211_is_mgmt(hdr->frame_control))
  			return RX_DROP_MONITOR;
  
  		if (ieee80211_is_action(hdr->frame_control)) {
  			u8 category;
  
  			/* make sure category field is present */
  			if (rx->skb->len < IEEE80211_MIN_ACTION_SIZE)
  				return RX_DROP_MONITOR;
  
  			mgmt = (struct ieee80211_mgmt *)hdr;
  			category = mgmt->u.action.category;
  			if (category != WLAN_CATEGORY_MESH_ACTION &&
  			    category != WLAN_CATEGORY_SELF_PROTECTED)
  				return RX_DROP_MONITOR;
  			return RX_CONTINUE;
  		}
  
  		if (ieee80211_is_probe_req(hdr->frame_control) ||
  		    ieee80211_is_probe_resp(hdr->frame_control) ||
  		    ieee80211_is_beacon(hdr->frame_control) ||
  		    ieee80211_is_auth(hdr->frame_control))
  			return RX_CONTINUE;
  
  		return RX_DROP_MONITOR;
  	}
  
  	return RX_CONTINUE;
  }
  
  static inline bool ieee80211_rx_reorder_ready(struct tid_ampdu_rx *tid_agg_rx,
  					      int index)
  {
  	struct sk_buff_head *frames = &tid_agg_rx->reorder_buf[index];
  	struct sk_buff *tail = skb_peek_tail(frames);
  	struct ieee80211_rx_status *status;
  
  	if (tid_agg_rx->reorder_buf_filtered & BIT_ULL(index))
  		return true;
  
  	if (!tail)
  		return false;
  
  	status = IEEE80211_SKB_RXCB(tail);
  	if (status->flag & RX_FLAG_AMSDU_MORE)
  		return false;
  
  	return true;
  }
  
  static void ieee80211_release_reorder_frame(struct ieee80211_sub_if_data *sdata,
  					    struct tid_ampdu_rx *tid_agg_rx,
  					    int index,
  					    struct sk_buff_head *frames)
  {
  	struct sk_buff_head *skb_list = &tid_agg_rx->reorder_buf[index];
  	struct sk_buff *skb;
  	struct ieee80211_rx_status *status;
  
  	lockdep_assert_held(&tid_agg_rx->reorder_lock);
  
  	if (skb_queue_empty(skb_list))
  		goto no_frame;
  
  	if (!ieee80211_rx_reorder_ready(tid_agg_rx, index)) {
  		__skb_queue_purge(skb_list);
  		goto no_frame;
  	}
  
  	/* release frames from the reorder ring buffer */
  	tid_agg_rx->stored_mpdu_num--;
  	while ((skb = __skb_dequeue(skb_list))) {
  		status = IEEE80211_SKB_RXCB(skb);
  		status->rx_flags |= IEEE80211_RX_DEFERRED_RELEASE;
  		__skb_queue_tail(frames, skb);
  	}
  
  no_frame:
  	tid_agg_rx->reorder_buf_filtered &= ~BIT_ULL(index);
  	tid_agg_rx->head_seq_num = ieee80211_sn_inc(tid_agg_rx->head_seq_num);
  }
  
  static void ieee80211_release_reorder_frames(struct ieee80211_sub_if_data *sdata,
  					     struct tid_ampdu_rx *tid_agg_rx,
  					     u16 head_seq_num,
  					     struct sk_buff_head *frames)
  {
  	int index;
  
  	lockdep_assert_held(&tid_agg_rx->reorder_lock);
  
  	while (ieee80211_sn_less(tid_agg_rx->head_seq_num, head_seq_num)) {
  		index = tid_agg_rx->head_seq_num % tid_agg_rx->buf_size;
  		ieee80211_release_reorder_frame(sdata, tid_agg_rx, index,
  						frames);
  	}
  }
  
  /*
   * Timeout (in jiffies) for skb's that are waiting in the RX reorder buffer. If
   * the skb was added to the buffer longer than this time ago, the earlier
   * frames that have not yet been received are assumed to be lost and the skb
   * can be released for processing. This may also release other skb's from the
   * reorder buffer if there are no additional gaps between the frames.
   *
   * Callers must hold tid_agg_rx->reorder_lock.
   */
  #define HT_RX_REORDER_BUF_TIMEOUT (HZ / 10)
  
  static void ieee80211_sta_reorder_release(struct ieee80211_sub_if_data *sdata,
  					  struct tid_ampdu_rx *tid_agg_rx,
  					  struct sk_buff_head *frames)
  {
  	int index, i, j;
  
  	lockdep_assert_held(&tid_agg_rx->reorder_lock);
  
  	/* release the buffer until next missing frame */
  	index = tid_agg_rx->head_seq_num % tid_agg_rx->buf_size;
  	if (!ieee80211_rx_reorder_ready(tid_agg_rx, index) &&
  	    tid_agg_rx->stored_mpdu_num) {
  		/*
  		 * No buffers ready to be released, but check whether any
  		 * frames in the reorder buffer have timed out.
  		 */
  		int skipped = 1;
  		for (j = (index + 1) % tid_agg_rx->buf_size; j != index;
  		     j = (j + 1) % tid_agg_rx->buf_size) {
  			if (!ieee80211_rx_reorder_ready(tid_agg_rx, j)) {
  				skipped++;
  				continue;
  			}
  			if (skipped &&
  			    !time_after(jiffies, tid_agg_rx->reorder_time[j] +
  					HT_RX_REORDER_BUF_TIMEOUT))
  				goto set_release_timer;
  
  			/* don't leave incomplete A-MSDUs around */
  			for (i = (index + 1) % tid_agg_rx->buf_size; i != j;
  			     i = (i + 1) % tid_agg_rx->buf_size)
  				__skb_queue_purge(&tid_agg_rx->reorder_buf[i]);
  
  			ht_dbg_ratelimited(sdata,
  					   "release an RX reorder frame due to timeout on earlier frames\n");
  			ieee80211_release_reorder_frame(sdata, tid_agg_rx, j,
  							frames);
  
  			/*
  			 * Increment the head seq# also for the skipped slots.
  			 */
  			tid_agg_rx->head_seq_num =
  				(tid_agg_rx->head_seq_num +
  				 skipped) & IEEE80211_SN_MASK;
  			skipped = 0;
  		}
  	} else while (ieee80211_rx_reorder_ready(tid_agg_rx, index)) {
  		ieee80211_release_reorder_frame(sdata, tid_agg_rx, index,
  						frames);
  		index =	tid_agg_rx->head_seq_num % tid_agg_rx->buf_size;
  	}
  
  	if (tid_agg_rx->stored_mpdu_num) {
  		j = index = tid_agg_rx->head_seq_num % tid_agg_rx->buf_size;
  
  		for (; j != (index - 1) % tid_agg_rx->buf_size;
  		     j = (j + 1) % tid_agg_rx->buf_size) {
  			if (ieee80211_rx_reorder_ready(tid_agg_rx, j))
  				break;
  		}
  
   set_release_timer:
  
  		if (!tid_agg_rx->removed)
  			mod_timer(&tid_agg_rx->reorder_timer,
  				  tid_agg_rx->reorder_time[j] + 1 +
  				  HT_RX_REORDER_BUF_TIMEOUT);
  	} else {
  		del_timer(&tid_agg_rx->reorder_timer);
  	}
  }
  
  /*
   * As this function belongs to the RX path it must be under
   * rcu_read_lock protection. It returns false if the frame
   * can be processed immediately, true if it was consumed.
   */
  static bool ieee80211_sta_manage_reorder_buf(struct ieee80211_sub_if_data *sdata,
  					     struct tid_ampdu_rx *tid_agg_rx,
  					     struct sk_buff *skb,
  					     struct sk_buff_head *frames)
  {
  	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
  	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
  	u16 sc = le16_to_cpu(hdr->seq_ctrl);
  	u16 mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4;
  	u16 head_seq_num, buf_size;
  	int index;
  	bool ret = true;
  
  	spin_lock(&tid_agg_rx->reorder_lock);
  
  	/*
  	 * Offloaded BA sessions have no known starting sequence number so pick
  	 * one from first Rxed frame for this tid after BA was started.
  	 */
  	if (unlikely(tid_agg_rx->auto_seq)) {
  		tid_agg_rx->auto_seq = false;
  		tid_agg_rx->ssn = mpdu_seq_num;
  		tid_agg_rx->head_seq_num = mpdu_seq_num;
  	}
  
  	buf_size = tid_agg_rx->buf_size;
  	head_seq_num = tid_agg_rx->head_seq_num;
  
  	/*
  	 * If the current MPDU's SN is smaller than the SSN, it shouldn't
  	 * be reordered.
  	 */
  	if (unlikely(!tid_agg_rx->started)) {
  		if (ieee80211_sn_less(mpdu_seq_num, head_seq_num)) {
  			ret = false;
  			goto out;
  		}
  		tid_agg_rx->started = true;
  	}
  
  	/* frame with out of date sequence number */
  	if (ieee80211_sn_less(mpdu_seq_num, head_seq_num)) {
  		dev_kfree_skb(skb);
  		goto out;
  	}
  
  	/*
  	 * If frame the sequence number exceeds our buffering window
  	 * size release some previous frames to make room for this one.
  	 */
  	if (!ieee80211_sn_less(mpdu_seq_num, head_seq_num + buf_size)) {
  		head_seq_num = ieee80211_sn_inc(
  				ieee80211_sn_sub(mpdu_seq_num, buf_size));
  		/* release stored frames up to new head to stack */
  		ieee80211_release_reorder_frames(sdata, tid_agg_rx,
  						 head_seq_num, frames);
  	}
  
  	/* Now the new frame is always in the range of the reordering buffer */
  
  	index = mpdu_seq_num % tid_agg_rx->buf_size;
  
  	/* check if we already stored this frame */
  	if (ieee80211_rx_reorder_ready(tid_agg_rx, index)) {
  		dev_kfree_skb(skb);
  		goto out;
  	}
  
  	/*
  	 * If the current MPDU is in the right order and nothing else
  	 * is stored we can process it directly, no need to buffer it.
  	 * If it is first but there's something stored, we may be able
  	 * to release frames after this one.
  	 */
  	if (mpdu_seq_num == tid_agg_rx->head_seq_num &&
  	    tid_agg_rx->stored_mpdu_num == 0) {
  		if (!(status->flag & RX_FLAG_AMSDU_MORE))
  			tid_agg_rx->head_seq_num =
  				ieee80211_sn_inc(tid_agg_rx->head_seq_num);
  		ret = false;
  		goto out;
  	}
  
  	/* put the frame in the reordering buffer */
  	__skb_queue_tail(&tid_agg_rx->reorder_buf[index], skb);
  	if (!(status->flag & RX_FLAG_AMSDU_MORE)) {
  		tid_agg_rx->reorder_time[index] = jiffies;
  		tid_agg_rx->stored_mpdu_num++;
  		ieee80211_sta_reorder_release(sdata, tid_agg_rx, frames);
  	}
  
   out:
  	spin_unlock(&tid_agg_rx->reorder_lock);
  	return ret;
  }
  
  /*
   * Reorder MPDUs from A-MPDUs, keeping them on a buffer. Returns
   * true if the MPDU was buffered, false if it should be processed.
   */
  static void ieee80211_rx_reorder_ampdu(struct ieee80211_rx_data *rx,
  				       struct sk_buff_head *frames)
  {
  	struct sk_buff *skb = rx->skb;
  	struct ieee80211_local *local = rx->local;
  	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
  	struct sta_info *sta = rx->sta;
  	struct tid_ampdu_rx *tid_agg_rx;
  	u16 sc;
  	u8 tid, ack_policy;
  
  	if (!ieee80211_is_data_qos(hdr->frame_control) ||
  	    is_multicast_ether_addr(hdr->addr1))
  		goto dont_reorder;
  
  	/*
  	 * filter the QoS data rx stream according to
  	 * STA/TID and check if this STA/TID is on aggregation
  	 */
  
  	if (!sta)
  		goto dont_reorder;
  
  	ack_policy = *ieee80211_get_qos_ctl(hdr) &
  		     IEEE80211_QOS_CTL_ACK_POLICY_MASK;
  	tid = ieee80211_get_tid(hdr);
  
  	tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
  	if (!tid_agg_rx) {
  		if (ack_policy == IEEE80211_QOS_CTL_ACK_POLICY_BLOCKACK &&
  		    !test_bit(tid, rx->sta->ampdu_mlme.agg_session_valid) &&
  		    !test_and_set_bit(tid, rx->sta->ampdu_mlme.unexpected_agg))
  			ieee80211_send_delba(rx->sdata, rx->sta->sta.addr, tid,
  					     WLAN_BACK_RECIPIENT,
  					     WLAN_REASON_QSTA_REQUIRE_SETUP);
  		goto dont_reorder;
  	}
  
  	/* qos null data frames are excluded */
  	if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC)))
  		goto dont_reorder;
  
  	/* not part of a BA session */
  	if (ack_policy != IEEE80211_QOS_CTL_ACK_POLICY_BLOCKACK &&
  	    ack_policy != IEEE80211_QOS_CTL_ACK_POLICY_NORMAL)
  		goto dont_reorder;
  
  	/* new, potentially un-ordered, ampdu frame - process it */
  
  	/* reset session timer */
  	if (tid_agg_rx->timeout)
  		tid_agg_rx->last_rx = jiffies;
  
  	/* if this mpdu is fragmented - terminate rx aggregation session */
  	sc = le16_to_cpu(hdr->seq_ctrl);
  	if (sc & IEEE80211_SCTL_FRAG) {
  		skb_queue_tail(&rx->sdata->skb_queue, skb);
  		ieee80211_queue_work(&local->hw, &rx->sdata->work);
  		return;
  	}
  
  	/*
  	 * No locking needed -- we will only ever process one
  	 * RX packet at a time, and thus own tid_agg_rx. All
  	 * other code manipulating it needs to (and does) make
  	 * sure that we cannot get to it any more before doing
  	 * anything with it.
  	 */
  	if (ieee80211_sta_manage_reorder_buf(rx->sdata, tid_agg_rx, skb,
  					     frames))
  		return;
  
   dont_reorder:
  	__skb_queue_tail(frames, skb);
  }
  
  static ieee80211_rx_result debug_noinline
  ieee80211_rx_h_check_dup(struct ieee80211_rx_data *rx)
  {
  	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
  	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
  
  	if (status->flag & RX_FLAG_DUP_VALIDATED)
  		return RX_CONTINUE;
  
  	/*
  	 * Drop duplicate 802.11 retransmissions
  	 * (IEEE 802.11-2012: 9.3.2.10 "Duplicate detection and recovery")
  	 */
  
  	if (rx->skb->len < 24)
  		return RX_CONTINUE;
  
  	if (ieee80211_is_ctl(hdr->frame_control) ||
  	    ieee80211_is_any_nullfunc(hdr->frame_control) ||
  	    is_multicast_ether_addr(hdr->addr1))
  		return RX_CONTINUE;
  
  	if (!rx->sta)
  		return RX_CONTINUE;
  
  	if (unlikely(ieee80211_has_retry(hdr->frame_control) &&
  		     rx->sta->last_seq_ctrl[rx->seqno_idx] == hdr->seq_ctrl)) {
  		I802_DEBUG_INC(rx->local->dot11FrameDuplicateCount);
  		rx->sta->rx_stats.num_duplicates++;
  		return RX_DROP_UNUSABLE;
  	} else if (!(status->flag & RX_FLAG_AMSDU_MORE)) {
  		rx->sta->last_seq_ctrl[rx->seqno_idx] = hdr->seq_ctrl;
  	}
  
  	return RX_CONTINUE;
  }
  
  static ieee80211_rx_result debug_noinline
  ieee80211_rx_h_check(struct ieee80211_rx_data *rx)
  {
  	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
  
  	/* Drop disallowed frame classes based on STA auth/assoc state;
  	 * IEEE 802.11, Chap 5.5.
  	 *
  	 * mac80211 filters only based on association state, i.e. it drops
  	 * Class 3 frames from not associated stations. hostapd sends
  	 * deauth/disassoc frames when needed. In addition, hostapd is
  	 * responsible for filtering on both auth and assoc states.
  	 */
  
  	if (ieee80211_vif_is_mesh(&rx->sdata->vif))
  		return ieee80211_rx_mesh_check(rx);
  
  	if (unlikely((ieee80211_is_data(hdr->frame_control) ||
  		      ieee80211_is_pspoll(hdr->frame_control)) &&
  		     rx->sdata->vif.type != NL80211_IFTYPE_ADHOC &&
  		     rx->sdata->vif.type != NL80211_IFTYPE_WDS &&
  		     rx->sdata->vif.type != NL80211_IFTYPE_OCB &&
  		     (!rx->sta || !test_sta_flag(rx->sta, WLAN_STA_ASSOC)))) {
  		/*
  		 * accept port control frames from the AP even when it's not
  		 * yet marked ASSOC to prevent a race where we don't set the
  		 * assoc bit quickly enough before it sends the first frame
  		 */
  		if (rx->sta && rx->sdata->vif.type == NL80211_IFTYPE_STATION &&
  		    ieee80211_is_data_present(hdr->frame_control)) {
  			unsigned int hdrlen;
  			__be16 ethertype;
  
  			hdrlen = ieee80211_hdrlen(hdr->frame_control);
  
  			if (rx->skb->len < hdrlen + 8)
  				return RX_DROP_MONITOR;
  
  			skb_copy_bits(rx->skb, hdrlen + 6, &ethertype, 2);
  			if (ethertype == rx->sdata->control_port_protocol)
  				return RX_CONTINUE;
  		}
  
  		if (rx->sdata->vif.type == NL80211_IFTYPE_AP &&
  		    cfg80211_rx_spurious_frame(rx->sdata->dev,
  					       hdr->addr2,
  					       GFP_ATOMIC))
  			return RX_DROP_UNUSABLE;
  
  		return RX_DROP_MONITOR;
  	}
  
  	return RX_CONTINUE;
  }
  
  
  static ieee80211_rx_result debug_noinline
  ieee80211_rx_h_check_more_data(struct ieee80211_rx_data *rx)
  {
  	struct ieee80211_local *local;
  	struct ieee80211_hdr *hdr;
  	struct sk_buff *skb;
  
  	local = rx->local;
  	skb = rx->skb;
  	hdr = (struct ieee80211_hdr *) skb->data;
  
  	if (!local->pspolling)
  		return RX_CONTINUE;
  
  	if (!ieee80211_has_fromds(hdr->frame_control))
  		/* this is not from AP */
  		return RX_CONTINUE;
  
  	if (!ieee80211_is_data(hdr->frame_control))
  		return RX_CONTINUE;
  
  	if (!ieee80211_has_moredata(hdr->frame_control)) {
  		/* AP has no more frames buffered for us */
  		local->pspolling = false;
  		return RX_CONTINUE;
  	}
  
  	/* more data bit is set, let's request a new frame from the AP */
  	ieee80211_send_pspoll(local, rx->sdata);
  
  	return RX_CONTINUE;
  }
  
  static void sta_ps_start(struct sta_info *sta)
  {
  	struct ieee80211_sub_if_data *sdata = sta->sdata;
  	struct ieee80211_local *local = sdata->local;
  	struct ps_data *ps;
  	int tid;
  
  	if (sta->sdata->vif.type == NL80211_IFTYPE_AP ||
  	    sta->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
  		ps = &sdata->bss->ps;
  	else
  		return;
  
  	atomic_inc(&ps->num_sta_ps);
  	set_sta_flag(sta, WLAN_STA_PS_STA);
  	if (!ieee80211_hw_check(&local->hw, AP_LINK_PS))
  		drv_sta_notify(local, sdata, STA_NOTIFY_SLEEP, &sta->sta);
  	ps_dbg(sdata, "STA %pM aid %d enters power save mode\n",
  	       sta->sta.addr, sta->sta.aid);
  
  	ieee80211_clear_fast_xmit(sta);
  
  	if (!sta->sta.txq[0])
  		return;
  
  	for (tid = 0; tid < IEEE80211_NUM_TIDS; tid++) {
  		struct ieee80211_txq *txq = sta->sta.txq[tid];
  		struct txq_info *txqi = to_txq_info(txq);
  
  		spin_lock(&local->active_txq_lock[txq->ac]);
  		if (!list_empty(&txqi->schedule_order))
  			list_del_init(&txqi->schedule_order);
  		spin_unlock(&local->active_txq_lock[txq->ac]);
  
  		if (txq_has_queue(txq))
  			set_bit(tid, &sta->txq_buffered_tids);
  		else
  			clear_bit(tid, &sta->txq_buffered_tids);
  	}
  }
  
  static void sta_ps_end(struct sta_info *sta)
  {
  	ps_dbg(sta->sdata, "STA %pM aid %d exits power save mode\n",
  	       sta->sta.addr, sta->sta.aid);
  
  	if (test_sta_flag(sta, WLAN_STA_PS_DRIVER)) {
  		/*
  		 * Clear the flag only if the other one is still set
  		 * so that the TX path won't start TX'ing new frames
  		 * directly ... In the case that the driver flag isn't
  		 * set ieee80211_sta_ps_deliver_wakeup() will clear it.
  		 */
  		clear_sta_flag(sta, WLAN_STA_PS_STA);
  		ps_dbg(sta->sdata, "STA %pM aid %d driver-ps-blocked\n",
  		       sta->sta.addr, sta->sta.aid);
  		return;
  	}
  
  	set_sta_flag(sta, WLAN_STA_PS_DELIVER);
  	clear_sta_flag(sta, WLAN_STA_PS_STA);
  	ieee80211_sta_ps_deliver_wakeup(sta);
  }
  
  int ieee80211_sta_ps_transition(struct ieee80211_sta *pubsta, bool start)
  {
  	struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
  	bool in_ps;
  
  	WARN_ON(!ieee80211_hw_check(&sta->local->hw, AP_LINK_PS));
  
  	/* Don't let the same PS state be set twice */
  	in_ps = test_sta_flag(sta, WLAN_STA_PS_STA);
  	if ((start && in_ps) || (!start && !in_ps))
  		return -EINVAL;
  
  	if (start)
  		sta_ps_start(sta);
  	else
  		sta_ps_end(sta);
  
  	return 0;
  }
  EXPORT_SYMBOL(ieee80211_sta_ps_transition);
  
  void ieee80211_sta_pspoll(struct ieee80211_sta *pubsta)
  {
  	struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
  
  	if (test_sta_flag(sta, WLAN_STA_SP))
  		return;
  
  	if (!test_sta_flag(sta, WLAN_STA_PS_DRIVER))
  		ieee80211_sta_ps_deliver_poll_response(sta);
  	else
  		set_sta_flag(sta, WLAN_STA_PSPOLL);
  }
  EXPORT_SYMBOL(ieee80211_sta_pspoll);
  
  void ieee80211_sta_uapsd_trigger(struct ieee80211_sta *pubsta, u8 tid)
  {
  	struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
  	int ac = ieee80211_ac_from_tid(tid);
  
  	/*
  	 * If this AC is not trigger-enabled do nothing unless the
  	 * driver is calling us after it already checked.
  	 *
  	 * NB: This could/should check a separate bitmap of trigger-
  	 * enabled queues, but for now we only implement uAPSD w/o
  	 * TSPEC changes to the ACs, so they're always the same.
  	 */
  	if (!(sta->sta.uapsd_queues & ieee80211_ac_to_qos_mask[ac]) &&
  	    tid != IEEE80211_NUM_TIDS)
  		return;
  
  	/* if we are in a service period, do nothing */
  	if (test_sta_flag(sta, WLAN_STA_SP))
  		return;
  
  	if (!test_sta_flag(sta, WLAN_STA_PS_DRIVER))
  		ieee80211_sta_ps_deliver_uapsd(sta);
  	else
  		set_sta_flag(sta, WLAN_STA_UAPSD);
  }
  EXPORT_SYMBOL(ieee80211_sta_uapsd_trigger);
  
  static ieee80211_rx_result debug_noinline
  ieee80211_rx_h_uapsd_and_pspoll(struct ieee80211_rx_data *rx)
  {
  	struct ieee80211_sub_if_data *sdata = rx->sdata;
  	struct ieee80211_hdr *hdr = (void *)rx->skb->data;
  	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
  
  	if (!rx->sta)
  		return RX_CONTINUE;
  
  	if (sdata->vif.type != NL80211_IFTYPE_AP &&
  	    sdata->vif.type != NL80211_IFTYPE_AP_VLAN)
  		return RX_CONTINUE;
  
  	/*
  	 * The device handles station powersave, so don't do anything about
  	 * uAPSD and PS-Poll frames (the latter shouldn't even come up from
  	 * it to mac80211 since they're handled.)
  	 */
  	if (ieee80211_hw_check(&sdata->local->hw, AP_LINK_PS))
  		return RX_CONTINUE;
  
  	/*
  	 * Don't do anything if the station isn't already asleep. In
  	 * the uAPSD case, the station will probably be marked asleep,
  	 * in the PS-Poll case the station must be confused ...
  	 */
  	if (!test_sta_flag(rx->sta, WLAN_STA_PS_STA))
  		return RX_CONTINUE;
  
  	if (unlikely(ieee80211_is_pspoll(hdr->frame_control))) {
  		ieee80211_sta_pspoll(&rx->sta->sta);
  
  		/* Free PS Poll skb here instead of returning RX_DROP that would
  		 * count as an dropped frame. */
  		dev_kfree_skb(rx->skb);
  
  		return RX_QUEUED;
  	} else if (!ieee80211_has_morefrags(hdr->frame_control) &&
  		   !(status->rx_flags & IEEE80211_RX_DEFERRED_RELEASE) &&
  		   ieee80211_has_pm(hdr->frame_control) &&
  		   (ieee80211_is_data_qos(hdr->frame_control) ||
  		    ieee80211_is_qos_nullfunc(hdr->frame_control))) {
  		u8 tid = ieee80211_get_tid(hdr);
  
  		ieee80211_sta_uapsd_trigger(&rx->sta->sta, tid);
  	}
  
  	return RX_CONTINUE;
  }
  
  static ieee80211_rx_result debug_noinline
  ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx)
  {
  	struct sta_info *sta = rx->sta;
  	struct sk_buff *skb = rx->skb;
  	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
  	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
  	int i;
  
  	if (!sta)
  		return RX_CONTINUE;
  
  	/*
  	 * Update last_rx only for IBSS packets which are for the current
  	 * BSSID and for station already AUTHORIZED to avoid keeping the
  	 * current IBSS network alive in cases where other STAs start
  	 * using different BSSID. This will also give the station another
  	 * chance to restart the authentication/authorization in case
  	 * something went wrong the first time.
  	 */
  	if (rx->sdata->vif.type == NL80211_IFTYPE_ADHOC) {
  		u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len,
  						NL80211_IFTYPE_ADHOC);
  		if (ether_addr_equal(bssid, rx->sdata->u.ibss.bssid) &&
  		    test_sta_flag(sta, WLAN_STA_AUTHORIZED)) {
  			sta->rx_stats.last_rx = jiffies;
  			if (ieee80211_is_data(hdr->frame_control) &&
  			    !is_multicast_ether_addr(hdr->addr1))
  				sta->rx_stats.last_rate =
  					sta_stats_encode_rate(status);
  		}
  	} else if (rx->sdata->vif.type == NL80211_IFTYPE_OCB) {
  		sta->rx_stats.last_rx = jiffies;
  	} else if (!ieee80211_is_s1g_beacon(hdr->frame_control) &&
  		   !is_multicast_ether_addr(hdr->addr1)) {
  		/*
  		 * Mesh beacons will update last_rx when if they are found to
  		 * match the current local configuration when processed.
  		 */
  		sta->rx_stats.last_rx = jiffies;
  		if (ieee80211_is_data(hdr->frame_control))
  			sta->rx_stats.last_rate = sta_stats_encode_rate(status);
  	}
  
  	sta->rx_stats.fragments++;
  
  	u64_stats_update_begin(&rx->sta->rx_stats.syncp);
  	sta->rx_stats.bytes += rx->skb->len;
  	u64_stats_update_end(&rx->sta->rx_stats.syncp);
  
  	if (!(status->flag & RX_FLAG_NO_SIGNAL_VAL)) {
  		sta->rx_stats.last_signal = status->signal;
  		ewma_signal_add(&sta->rx_stats_avg.signal, -status->signal);
  	}
  
  	if (status->chains) {
  		sta->rx_stats.chains = status->chains;
  		for (i = 0; i < ARRAY_SIZE(status->chain_signal); i++) {
  			int signal = status->chain_signal[i];
  
  			if (!(status->chains & BIT(i)))
  				continue;
  
  			sta->rx_stats.chain_signal_last[i] = signal;
  			ewma_signal_add(&sta->rx_stats_avg.chain_signal[i],
  					-signal);
  		}
  	}
  
  	if (ieee80211_is_s1g_beacon(hdr->frame_control))
  		return RX_CONTINUE;
  
  	/*
  	 * Change STA power saving mode only at the end of a frame
  	 * exchange sequence, and only for a data or management
  	 * frame as specified in IEEE 802.11-2016 11.2.3.2
  	 */
  	if (!ieee80211_hw_check(&sta->local->hw, AP_LINK_PS) &&
  	    !ieee80211_has_morefrags(hdr->frame_control) &&
  	    !is_multicast_ether_addr(hdr->addr1) &&
  	    (ieee80211_is_mgmt(hdr->frame_control) ||
  	     ieee80211_is_data(hdr->frame_control)) &&
  	    !(status->rx_flags & IEEE80211_RX_DEFERRED_RELEASE) &&
  	    (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
  	     rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)) {
  		if (test_sta_flag(sta, WLAN_STA_PS_STA)) {
  			if (!ieee80211_has_pm(hdr->frame_control))
  				sta_ps_end(sta);
  		} else {
  			if (ieee80211_has_pm(hdr->frame_control))
  				sta_ps_start(sta);
  		}
  	}
  
  	/* mesh power save support */
  	if (ieee80211_vif_is_mesh(&rx->sdata->vif))
  		ieee80211_mps_rx_h_sta_process(sta, hdr);
  
  	/*
  	 * Drop (qos-)data::nullfunc frames silently, since they
  	 * are used only to control station power saving mode.
  	 */
  	if (ieee80211_is_any_nullfunc(hdr->frame_control)) {
  		I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
  
  		/*
  		 * If we receive a 4-addr nullfunc frame from a STA
  		 * that was not moved to a 4-addr STA vlan yet send
  		 * the event to userspace and for older hostapd drop
  		 * the frame to the monitor interface.
  		 */
  		if (ieee80211_has_a4(hdr->frame_control) &&
  		    (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
  		     (rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
  		      !rx->sdata->u.vlan.sta))) {
  			if (!test_and_set_sta_flag(sta, WLAN_STA_4ADDR_EVENT))
  				cfg80211_rx_unexpected_4addr_frame(
  					rx->sdata->dev, sta->sta.addr,
  					GFP_ATOMIC);
  			return RX_DROP_MONITOR;
  		}
  		/*
  		 * Update counter and free packet here to avoid
  		 * counting this as a dropped packed.
  		 */
  		sta->rx_stats.packets++;
  		dev_kfree_skb(rx->skb);
  		return RX_QUEUED;
  	}
  
  	return RX_CONTINUE;
  } /* ieee80211_rx_h_sta_process */
  
  static struct ieee80211_key *
  ieee80211_rx_get_bigtk(struct ieee80211_rx_data *rx, int idx)
  {
  	struct ieee80211_key *key = NULL;
  	struct ieee80211_sub_if_data *sdata = rx->sdata;
  	int idx2;
  
  	/* Make sure key gets set if either BIGTK key index is set so that
  	 * ieee80211_drop_unencrypted_mgmt() can properly drop both unprotected
  	 * Beacon frames and Beacon frames that claim to use another BIGTK key
  	 * index (i.e., a key that we do not have).
  	 */
  
  	if (idx < 0) {
  		idx = NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS;
  		idx2 = idx + 1;
  	} else {
  		if (idx == NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
  			idx2 = idx + 1;
  		else
  			idx2 = idx - 1;
  	}
  
  	if (rx->sta)
  		key = rcu_dereference(rx->sta->gtk[idx]);
  	if (!key)
  		key = rcu_dereference(sdata->keys[idx]);
  	if (!key && rx->sta)
  		key = rcu_dereference(rx->sta->gtk[idx2]);
  	if (!key)
  		key = rcu_dereference(sdata->keys[idx2]);
  
  	return key;
  }
  
  static ieee80211_rx_result debug_noinline
  ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
  {
  	struct sk_buff *skb = rx->skb;
  	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
  	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
  	int keyidx;
  	ieee80211_rx_result result = RX_DROP_UNUSABLE;
  	struct ieee80211_key *sta_ptk = NULL;
  	struct ieee80211_key *ptk_idx = NULL;
  	int mmie_keyidx = -1;
  	__le16 fc;
  	const struct ieee80211_cipher_scheme *cs = NULL;
  
  	if (ieee80211_is_ext(hdr->frame_control))
  		return RX_CONTINUE;
  
  	/*
  	 * Key selection 101
  	 *
  	 * There are five types of keys:
  	 *  - GTK (group keys)
  	 *  - IGTK (group keys for management frames)
  	 *  - BIGTK (group keys for Beacon frames)
  	 *  - PTK (pairwise keys)
  	 *  - STK (station-to-station pairwise keys)
  	 *
  	 * When selecting a key, we have to distinguish between multicast
  	 * (including broadcast) and unicast frames, the latter can only
  	 * use PTKs and STKs while the former always use GTKs, IGTKs, and
  	 * BIGTKs. Unless, of course, actual WEP keys ("pre-RSNA") are used,
  	 * then unicast frames can also use key indices like GTKs. Hence, if we
  	 * don't have a PTK/STK we check the key index for a WEP key.
  	 *
  	 * Note that in a regular BSS, multicast frames are sent by the
  	 * AP only, associated stations unicast the frame to the AP first
  	 * which then multicasts it on their behalf.
  	 *
  	 * There is also a slight problem in IBSS mode: GTKs are negotiated
  	 * with each station, that is something we don't currently handle.
  	 * The spec seems to expect that one negotiates the same key with
  	 * every station but there's no such requirement; VLANs could be
  	 * possible.
  	 */
  
  	/* start without a key */
  	rx->key = NULL;
  	fc = hdr->frame_control;
  
  	if (rx->sta) {
  		int keyid = rx->sta->ptk_idx;
  		sta_ptk = rcu_dereference(rx->sta->ptk[keyid]);
  
  		if (ieee80211_has_protected(fc)) {
  			cs = rx->sta->cipher_scheme;
  			keyid = ieee80211_get_keyid(rx->skb, cs);
  
  			if (unlikely(keyid < 0))
  				return RX_DROP_UNUSABLE;
  
  			ptk_idx = rcu_dereference(rx->sta->ptk[keyid]);
  		}
  	}
  
  	if (!ieee80211_has_protected(fc))
  		mmie_keyidx = ieee80211_get_mmie_keyidx(rx->skb);
  
  	if (!is_multicast_ether_addr(hdr->addr1) && sta_ptk) {
  		rx->key = ptk_idx ? ptk_idx : sta_ptk;
  		if ((status->flag & RX_FLAG_DECRYPTED) &&
  		    (status->flag & RX_FLAG_IV_STRIPPED))
  			return RX_CONTINUE;
  		/* Skip decryption if the frame is not protected. */
  		if (!ieee80211_has_protected(fc))
  			return RX_CONTINUE;
  	} else if (mmie_keyidx >= 0 && ieee80211_is_beacon(fc)) {
  		/* Broadcast/multicast robust management frame / BIP */
  		if ((status->flag & RX_FLAG_DECRYPTED) &&
  		    (status->flag & RX_FLAG_IV_STRIPPED))
  			return RX_CONTINUE;
  
  		if (mmie_keyidx < NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS ||
  		    mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS +
  		    NUM_DEFAULT_BEACON_KEYS) {
  			cfg80211_rx_unprot_mlme_mgmt(rx->sdata->dev,
  						     skb->data,
  						     skb->len);
  			return RX_DROP_MONITOR; /* unexpected BIP keyidx */
  		}
  
  		rx->key = ieee80211_rx_get_bigtk(rx, mmie_keyidx);
  		if (!rx->key)
  			return RX_CONTINUE; /* Beacon protection not in use */
  	} else if (mmie_keyidx >= 0) {
  		/* Broadcast/multicast robust management frame / BIP */
  		if ((status->flag & RX_FLAG_DECRYPTED) &&
  		    (status->flag & RX_FLAG_IV_STRIPPED))
  			return RX_CONTINUE;
  
  		if (mmie_keyidx < NUM_DEFAULT_KEYS ||
  		    mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
  			return RX_DROP_MONITOR; /* unexpected BIP keyidx */
  		if (rx->sta) {
  			if (ieee80211_is_group_privacy_action(skb) &&
  			    test_sta_flag(rx->sta, WLAN_STA_MFP))
  				return RX_DROP_MONITOR;
  
  			rx->key = rcu_dereference(rx->sta->gtk[mmie_keyidx]);
  		}
  		if (!rx->key)
  			rx->key = rcu_dereference(rx->sdata->keys[mmie_keyidx]);
  	} else if (!ieee80211_has_protected(fc)) {
  		/*
  		 * The frame was not protected, so skip decryption. However, we
  		 * need to set rx->key if there is a key that could have been
  		 * used so that the frame may be dropped if encryption would
  		 * have been expected.
  		 */
  		struct ieee80211_key *key = NULL;
  		struct ieee80211_sub_if_data *sdata = rx->sdata;
  		int i;
  
  		if (ieee80211_is_beacon(fc)) {
  			key = ieee80211_rx_get_bigtk(rx, -1);
  		} else if (ieee80211_is_mgmt(fc) &&
  			   is_multicast_ether_addr(hdr->addr1)) {
  			key = rcu_dereference(rx->sdata->default_mgmt_key);
  		} else {
  			if (rx->sta) {
  				for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
  					key = rcu_dereference(rx->sta->gtk[i]);
  					if (key)
  						break;
  				}
  			}
  			if (!key) {
  				for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
  					key = rcu_dereference(sdata->keys[i]);
  					if (key)
  						break;
  				}
  			}
  		}
  		if (key)
  			rx->key = key;
  		return RX_CONTINUE;
  	} else {
  		/*
  		 * The device doesn't give us the IV so we won't be
  		 * able to look up the key. That's ok though, we
  		 * don't need to decrypt the frame, we just won't
  		 * be able to keep statistics accurate.
  		 * Except for key threshold notifications, should
  		 * we somehow allow the driver to tell us which key
  		 * the hardware used if this flag is set?
  		 */
  		if ((status->flag & RX_FLAG_DECRYPTED) &&
  		    (status->flag & RX_FLAG_IV_STRIPPED))
  			return RX_CONTINUE;
  
  		keyidx = ieee80211_get_keyid(rx->skb, cs);
  
  		if (unlikely(keyidx < 0))
  			return RX_DROP_UNUSABLE;
  
  		/* check per-station GTK first, if multicast packet */
  		if (is_multicast_ether_addr(hdr->addr1) && rx->sta)
  			rx->key = rcu_dereference(rx->sta->gtk[keyidx]);
  
  		/* if not found, try default key */
  		if (!rx->key) {
  			rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
  
  			/*
  			 * RSNA-protected unicast frames should always be
  			 * sent with pairwise or station-to-station keys,
  			 * but for WEP we allow using a key index as well.
  			 */
  			if (rx->key &&
  			    rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP40 &&
  			    rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP104 &&
  			    !is_multicast_ether_addr(hdr->addr1))
  				rx->key = NULL;
  		}
  	}
  
  	if (rx->key) {
  		if (unlikely(rx->key->flags & KEY_FLAG_TAINTED))
  			return RX_DROP_MONITOR;
  
  		/* TODO: add threshold stuff again */
  	} else {
  		return RX_DROP_MONITOR;
  	}
  
  	switch (rx->key->conf.cipher) {
  	case WLAN_CIPHER_SUITE_WEP40:
  	case WLAN_CIPHER_SUITE_WEP104:
  		result = ieee80211_crypto_wep_decrypt(rx);
  		break;
  	case WLAN_CIPHER_SUITE_TKIP:
  		result = ieee80211_crypto_tkip_decrypt(rx);
  		break;
  	case WLAN_CIPHER_SUITE_CCMP:
  		result = ieee80211_crypto_ccmp_decrypt(
  			rx, IEEE80211_CCMP_MIC_LEN);
  		break;
  	case WLAN_CIPHER_SUITE_CCMP_256:
  		result = ieee80211_crypto_ccmp_decrypt(
  			rx, IEEE80211_CCMP_256_MIC_LEN);
  		break;
  	case WLAN_CIPHER_SUITE_AES_CMAC:
  		result = ieee80211_crypto_aes_cmac_decrypt(rx);
  		break;
  	case WLAN_CIPHER_SUITE_BIP_CMAC_256:
  		result = ieee80211_crypto_aes_cmac_256_decrypt(rx);
  		break;
  	case WLAN_CIPHER_SUITE_BIP_GMAC_128:
  	case WLAN_CIPHER_SUITE_BIP_GMAC_256:
  		result = ieee80211_crypto_aes_gmac_decrypt(rx);
  		break;
  	case WLAN_CIPHER_SUITE_GCMP:
  	case WLAN_CIPHER_SUITE_GCMP_256:
  		result = ieee80211_crypto_gcmp_decrypt(rx);
  		break;
  	default:
  		result = ieee80211_crypto_hw_decrypt(rx);
  	}
  
  	/* the hdr variable is invalid after the decrypt handlers */
  
  	/* either the frame has been decrypted or will be dropped */
  	status->flag |= RX_FLAG_DECRYPTED;
  
  	if (unlikely(ieee80211_is_beacon(fc) && result == RX_DROP_UNUSABLE))
  		cfg80211_rx_unprot_mlme_mgmt(rx->sdata->dev,
  					     skb->data, skb->len);
  
  	return result;
  }
  
  void ieee80211_init_frag_cache(struct ieee80211_fragment_cache *cache)
  {
  	int i;
  
  	for (i = 0; i < ARRAY_SIZE(cache->entries); i++)
  		skb_queue_head_init(&cache->entries[i].skb_list);
  }
  
  void ieee80211_destroy_frag_cache(struct ieee80211_fragment_cache *cache)
  {
  	int i;
  
  	for (i = 0; i < ARRAY_SIZE(cache->entries); i++)
  		__skb_queue_purge(&cache->entries[i].skb_list);
  }
  
  static inline struct ieee80211_fragment_entry *
  ieee80211_reassemble_add(struct ieee80211_fragment_cache *cache,
  			 unsigned int frag, unsigned int seq, int rx_queue,
  			 struct sk_buff **skb)
  {
  	struct ieee80211_fragment_entry *entry;
  
  	entry = &cache->entries[cache->next++];
  	if (cache->next >= IEEE80211_FRAGMENT_MAX)
  		cache->next = 0;
  
  	__skb_queue_purge(&entry->skb_list);
  
  	__skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
  	*skb = NULL;
  	entry->first_frag_time = jiffies;
  	entry->seq = seq;
  	entry->rx_queue = rx_queue;
  	entry->last_frag = frag;
  	entry->check_sequential_pn = false;
  	entry->extra_len = 0;
  
  	return entry;
  }
  
  static inline struct ieee80211_fragment_entry *
  ieee80211_reassemble_find(struct ieee80211_fragment_cache *cache,
  			  unsigned int frag, unsigned int seq,
  			  int rx_queue, struct ieee80211_hdr *hdr)
  {
  	struct ieee80211_fragment_entry *entry;
  	int i, idx;
  
  	idx = cache->next;
  	for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
  		struct ieee80211_hdr *f_hdr;
  		struct sk_buff *f_skb;
  
  		idx--;
  		if (idx < 0)
  			idx = IEEE80211_FRAGMENT_MAX - 1;
  
  		entry = &cache->entries[idx];
  		if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
  		    entry->rx_queue != rx_queue ||
  		    entry->last_frag + 1 != frag)
  			continue;
  
  		f_skb = __skb_peek(&entry->skb_list);
  		f_hdr = (struct ieee80211_hdr *) f_skb->data;
  
  		/*
  		 * Check ftype and addresses are equal, else check next fragment
  		 */
  		if (((hdr->frame_control ^ f_hdr->frame_control) &
  		     cpu_to_le16(IEEE80211_FCTL_FTYPE)) ||
  		    !ether_addr_equal(hdr->addr1, f_hdr->addr1) ||
  		    !ether_addr_equal(hdr->addr2, f_hdr->addr2))
  			continue;
  
  		if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) {
  			__skb_queue_purge(&entry->skb_list);
  			continue;
  		}
  		return entry;
  	}
  
  	return NULL;
  }
  
  static bool requires_sequential_pn(struct ieee80211_rx_data *rx, __le16 fc)
  {
  	return rx->key &&
  		(rx->key->conf.cipher == WLAN_CIPHER_SUITE_CCMP ||
  		 rx->key->conf.cipher == WLAN_CIPHER_SUITE_CCMP_256 ||
  		 rx->key->conf.cipher == WLAN_CIPHER_SUITE_GCMP ||
  		 rx->key->conf.cipher == WLAN_CIPHER_SUITE_GCMP_256) &&
  		ieee80211_has_protected(fc);
  }
  
  static ieee80211_rx_result debug_noinline
  ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
  {
  	struct ieee80211_fragment_cache *cache = &rx->sdata->frags;
  	struct ieee80211_hdr *hdr;
  	u16 sc;
  	__le16 fc;
  	unsigned int frag, seq;
  	struct ieee80211_fragment_entry *entry;
  	struct sk_buff *skb;
  	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
  
  	hdr = (struct ieee80211_hdr *)rx->skb->data;
  	fc = hdr->frame_control;
  
  	if (ieee80211_is_ctl(fc) || ieee80211_is_ext(fc))
  		return RX_CONTINUE;
  
  	sc = le16_to_cpu(hdr->seq_ctrl);
  	frag = sc & IEEE80211_SCTL_FRAG;
  
  	if (rx->sta)
  		cache = &rx->sta->frags;
  
  	if (likely(!ieee80211_has_morefrags(fc) && frag == 0))
  		goto out;
  
  	if (is_multicast_ether_addr(hdr->addr1))
  		return RX_DROP_MONITOR;
  
  	I802_DEBUG_INC(rx->local->rx_handlers_fragments);
  
  	if (skb_linearize(rx->skb))
  		return RX_DROP_UNUSABLE;
  
  	/*
  	 *  skb_linearize() might change the skb->data and
  	 *  previously cached variables (in this case, hdr) need to
  	 *  be refreshed with the new data.
  	 */
  	hdr = (struct ieee80211_hdr *)rx->skb->data;
  	seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
  
  	if (frag == 0) {
  		/* This is the first fragment of a new frame. */
  		entry = ieee80211_reassemble_add(cache, frag, seq,
  						 rx->seqno_idx, &(rx->skb));
  		if (requires_sequential_pn(rx, fc)) {
  			int queue = rx->security_idx;
  
  			/* Store CCMP/GCMP PN so that we can verify that the
  			 * next fragment has a sequential PN value.
  			 */
  			entry->check_sequential_pn = true;
  			entry->is_protected = true;
  			entry->key_color = rx->key->color;
  			memcpy(entry->last_pn,
  			       rx->key->u.ccmp.rx_pn[queue],
  			       IEEE80211_CCMP_PN_LEN);
  			BUILD_BUG_ON(offsetof(struct ieee80211_key,
  					      u.ccmp.rx_pn) !=
  				     offsetof(struct ieee80211_key,
  					      u.gcmp.rx_pn));
  			BUILD_BUG_ON(sizeof(rx->key->u.ccmp.rx_pn[queue]) !=
  				     sizeof(rx->key->u.gcmp.rx_pn[queue]));
  			BUILD_BUG_ON(IEEE80211_CCMP_PN_LEN !=
  				     IEEE80211_GCMP_PN_LEN);
  		} else if (rx->key &&
  			   (ieee80211_has_protected(fc) ||
  			    (status->flag & RX_FLAG_DECRYPTED))) {
  			entry->is_protected = true;
  			entry->key_color = rx->key->color;
  		}
  		return RX_QUEUED;
  	}
  
  	/* This is a fragment for a frame that should already be pending in
  	 * fragment cache. Add this fragment to the end of the pending entry.
  	 */
  	entry = ieee80211_reassemble_find(cache, frag, seq,
  					  rx->seqno_idx, hdr);
  	if (!entry) {
  		I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
  		return RX_DROP_MONITOR;
  	}
  
  	/* "The receiver shall discard MSDUs and MMPDUs whose constituent
  	 *  MPDU PN values are not incrementing in steps of 1."
  	 * see IEEE P802.11-REVmc/D5.0, 12.5.3.4.4, item d (for CCMP)
  	 * and IEEE P802.11-REVmc/D5.0, 12.5.5.4.4, item d (for GCMP)
  	 */
  	if (entry->check_sequential_pn) {
  		int i;
  		u8 pn[IEEE80211_CCMP_PN_LEN], *rpn;
  
  		if (!requires_sequential_pn(rx, fc))
  			return RX_DROP_UNUSABLE;
  
  		/* Prevent mixed key and fragment cache attacks */
  		if (entry->key_color != rx->key->color)
  			return RX_DROP_UNUSABLE;
  
  		memcpy(pn, entry->last_pn, IEEE80211_CCMP_PN_LEN);
  		for (i = IEEE80211_CCMP_PN_LEN - 1; i >= 0; i--) {
  			pn[i]++;
  			if (pn[i])
  				break;
  		}
  
  		rpn = rx->ccm_gcm.pn;
  		if (memcmp(pn, rpn, IEEE80211_CCMP_PN_LEN))
  			return RX_DROP_UNUSABLE;
  		memcpy(entry->last_pn, pn, IEEE80211_CCMP_PN_LEN);
  	} else if (entry->is_protected &&
  		   (!rx->key ||
  		    (!ieee80211_has_protected(fc) &&
  		     !(status->flag & RX_FLAG_DECRYPTED)) ||
  		    rx->key->color != entry->key_color)) {
  		/* Drop this as a mixed key or fragment cache attack, even
  		 * if for TKIP Michael MIC should protect us, and WEP is a
  		 * lost cause anyway.
  		 */
  		return RX_DROP_UNUSABLE;
  	} else if (entry->is_protected && rx->key &&
  		   entry->key_color != rx->key->color &&
  		   (status->flag & RX_FLAG_DECRYPTED)) {
  		return RX_DROP_UNUSABLE;
  	}
  
  	skb_pull(rx->skb, ieee80211_hdrlen(fc));
  	__skb_queue_tail(&entry->skb_list, rx->skb);
  	entry->last_frag = frag;
  	entry->extra_len += rx->skb->len;
  	if (ieee80211_has_morefrags(fc)) {
  		rx->skb = NULL;
  		return RX_QUEUED;
  	}
  
  	rx->skb = __skb_dequeue(&entry->skb_list);
  	if (skb_tailroom(rx->skb) < entry->extra_len) {
  		I802_DEBUG_INC(rx->local->rx_expand_skb_head_defrag);
  		if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
  					      GFP_ATOMIC))) {
  			I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
  			__skb_queue_purge(&entry->skb_list);
  			return RX_DROP_UNUSABLE;
  		}
  	}
  	while ((skb = __skb_dequeue(&entry->skb_list))) {
  		skb_put_data(rx->skb, skb->data, skb->len);
  		dev_kfree_skb(skb);
  	}
  
   out:
  	ieee80211_led_rx(rx->local);
  	if (rx->sta)
  		rx->sta->rx_stats.packets++;
  	return RX_CONTINUE;
  }
  
  static int ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx)
  {
  	if (unlikely(!rx->sta || !test_sta_flag(rx->sta, WLAN_STA_AUTHORIZED)))
  		return -EACCES;
  
  	return 0;
  }
  
  static int ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx, __le16 fc)
  {
  	struct ieee80211_hdr *hdr = (void *)rx->skb->data;
  	struct sk_buff *skb = rx->skb;
  	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
  
  	/*
  	 * Pass through unencrypted frames if the hardware has
  	 * decrypted them already.
  	 */
  	if (status->flag & RX_FLAG_DECRYPTED)
  		return 0;
  
  	/* check mesh EAPOL frames first */
  	if (unlikely(rx->sta && ieee80211_vif_is_mesh(&rx->sdata->vif) &&
  		     ieee80211_is_data(fc))) {
  		struct ieee80211s_hdr *mesh_hdr;
  		u16 hdr_len = ieee80211_hdrlen(fc);
  		u16 ethertype_offset;
  		__be16 ethertype;
  
  		if (!ether_addr_equal(hdr->addr1, rx->sdata->vif.addr))
  			goto drop_check;
  
  		/* make sure fixed part of mesh header is there, also checks skb len */
  		if (!pskb_may_pull(rx->skb, hdr_len + 6))
  			goto drop_check;
  
  		mesh_hdr = (struct ieee80211s_hdr *)(skb->data + hdr_len);
  		ethertype_offset = hdr_len + ieee80211_get_mesh_hdrlen(mesh_hdr) +
  				   sizeof(rfc1042_header);
  
  		if (skb_copy_bits(rx->skb, ethertype_offset, &ethertype, 2) == 0 &&
  		    ethertype == rx->sdata->control_port_protocol)
  			return 0;
  	}
  
  drop_check:
  	/* Drop unencrypted frames if key is set. */
  	if (unlikely(!ieee80211_has_protected(fc) &&
  		     !ieee80211_is_any_nullfunc(fc) &&
  		     ieee80211_is_data(fc) && rx->key))
  		return -EACCES;
  
  	return 0;
  }
  
  static int ieee80211_drop_unencrypted_mgmt(struct ieee80211_rx_data *rx)
  {
  	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
  	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
  	__le16 fc = hdr->frame_control;
  
  	/*
  	 * Pass through unencrypted frames if the hardware has
  	 * decrypted them already.
  	 */
  	if (status->flag & RX_FLAG_DECRYPTED)
  		return 0;
  
  	if (rx->sta && test_sta_flag(rx->sta, WLAN_STA_MFP)) {
  		if (unlikely(!ieee80211_has_protected(fc) &&
  			     ieee80211_is_unicast_robust_mgmt_frame(rx->skb) &&
  			     rx->key)) {
  			if (ieee80211_is_deauth(fc) ||
  			    ieee80211_is_disassoc(fc))
  				cfg80211_rx_unprot_mlme_mgmt(rx->sdata->dev,
  							     rx->skb->data,
  							     rx->skb->len);
  			return -EACCES;
  		}
  		/* BIP does not use Protected field, so need to check MMIE */
  		if (unlikely(ieee80211_is_multicast_robust_mgmt_frame(rx->skb) &&
  			     ieee80211_get_mmie_keyidx(rx->skb) < 0)) {
  			if (ieee80211_is_deauth(fc) ||
  			    ieee80211_is_disassoc(fc))
  				cfg80211_rx_unprot_mlme_mgmt(rx->sdata->dev,
  							     rx->skb->data,
  							     rx->skb->len);
  			return -EACCES;
  		}
  		if (unlikely(ieee80211_is_beacon(fc) && rx->key &&
  			     ieee80211_get_mmie_keyidx(rx->skb) < 0)) {
  			cfg80211_rx_unprot_mlme_mgmt(rx->sdata->dev,
  						     rx->skb->data,
  						     rx->skb->len);
  			return -EACCES;
  		}
  		/*
  		 * When using MFP, Action frames are not allowed prior to
  		 * having configured keys.
  		 */
  		if (unlikely(ieee80211_is_action(fc) && !rx->key &&
  			     ieee80211_is_robust_mgmt_frame(rx->skb)))
  			return -EACCES;
  	}
  
  	return 0;
  }
  
  static int
  __ieee80211_data_to_8023(struct ieee80211_rx_data *rx, bool *port_control)
  {
  	struct ieee80211_sub_if_data *sdata = rx->sdata;
  	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
  	bool check_port_control = false;
  	struct ethhdr *ehdr;
  	int ret;
  
  	*port_control = false;
  	if (ieee80211_has_a4(hdr->frame_control) &&
  	    sdata->vif.type == NL80211_IFTYPE_AP_VLAN && !sdata->u.vlan.sta)
  		return -1;
  
  	if (sdata->vif.type == NL80211_IFTYPE_STATION &&
  	    !!sdata->u.mgd.use_4addr != !!ieee80211_has_a4(hdr->frame_control)) {
  
  		if (!sdata->u.mgd.use_4addr)
  			return -1;
  		else if (!ether_addr_equal(hdr->addr1, sdata->vif.addr))
  			check_port_control = true;
  	}
  
  	if (is_multicast_ether_addr(hdr->addr1) &&
  	    sdata->vif.type == NL80211_IFTYPE_AP_VLAN && sdata->u.vlan.sta)
  		return -1;
  
  	ret = ieee80211_data_to_8023(rx->skb, sdata->vif.addr, sdata->vif.type);
  	if (ret < 0)
  		return ret;
  
  	ehdr = (struct ethhdr *) rx->skb->data;
  	if (ehdr->h_proto == rx->sdata->control_port_protocol)
  		*port_control = true;
  	else if (check_port_control)
  		return -1;
  
  	return 0;
  }
  
  /*
   * requires that rx->skb is a frame with ethernet header
   */
  static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx, __le16 fc)
  {
  	static const u8 pae_group_addr[ETH_ALEN] __aligned(2)
  		= { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 };
  	struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
  
  	/*
  	 * Allow EAPOL frames to us/the PAE group address regardless of
  	 * whether the frame was encrypted or not, and always disallow
  	 * all other destination addresses for them.
  	 */
  	if (unlikely(ehdr->h_proto == rx->sdata->control_port_protocol))
  		return ether_addr_equal(ehdr->h_dest, rx->sdata->vif.addr) ||
  		       ether_addr_equal(ehdr->h_dest, pae_group_addr);
  
  	if (ieee80211_802_1x_port_control(rx) ||
  	    ieee80211_drop_unencrypted(rx, fc))
  		return false;
  
  	return true;
  }
  
  static void ieee80211_deliver_skb_to_local_stack(struct sk_buff *skb,
  						 struct ieee80211_rx_data *rx)
  {
  	struct ieee80211_sub_if_data *sdata = rx->sdata;
  	struct net_device *dev = sdata->dev;
  
  	if (unlikely((skb->protocol == sdata->control_port_protocol ||
  		     (skb->protocol == cpu_to_be16(ETH_P_PREAUTH) &&
  		      !sdata->control_port_no_preauth)) &&
  		     sdata->control_port_over_nl80211)) {
  		struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
  		bool noencrypt = !(status->flag & RX_FLAG_DECRYPTED);
  
  		cfg80211_rx_control_port(dev, skb, noencrypt);
  		dev_kfree_skb(skb);
  	} else {
  		struct ethhdr *ehdr = (void *)skb_mac_header(skb);
  
  		memset(skb->cb, 0, sizeof(skb->cb));
  
  		/*
  		 * 802.1X over 802.11 requires that the authenticator address
  		 * be used for EAPOL frames. However, 802.1X allows the use of
  		 * the PAE group address instead. If the interface is part of
  		 * a bridge and we pass the frame with the PAE group address,
  		 * then the bridge will forward it to the network (even if the
  		 * client was not associated yet), which isn't supposed to
  		 * happen.
  		 * To avoid that, rewrite the destination address to our own
  		 * address, so that the authenticator (e.g. hostapd) will see
  		 * the frame, but bridge won't forward it anywhere else. Note
  		 * that due to earlier filtering, the only other address can
  		 * be the PAE group address.
  		 */
  		if (unlikely(skb->protocol == sdata->control_port_protocol &&
  			     !ether_addr_equal(ehdr->h_dest, sdata->vif.addr)))
  			ether_addr_copy(ehdr->h_dest, sdata->vif.addr);
  
  		/* deliver to local stack */
  		if (rx->list)
  			list_add_tail(&skb->list, rx->list);
  		else
  			netif_receive_skb(skb);
  	}
  }
  
  /*
   * requires that rx->skb is a frame with ethernet header
   */
  static void
  ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
  {
  	struct ieee80211_sub_if_data *sdata = rx->sdata;
  	struct net_device *dev = sdata->dev;
  	struct sk_buff *skb, *xmit_skb;
  	struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
  	struct sta_info *dsta;
  
  	skb = rx->skb;
  	xmit_skb = NULL;
  
  	ieee80211_rx_stats(dev, skb->len);
  
  	if (rx->sta) {
  		/* The seqno index has the same property as needed
  		 * for the rx_msdu field, i.e. it is IEEE80211_NUM_TIDS
  		 * for non-QoS-data frames. Here we know it's a data
  		 * frame, so count MSDUs.
  		 */
  		u64_stats_update_begin(&rx->sta->rx_stats.syncp);
  		rx->sta->rx_stats.msdu[rx->seqno_idx]++;
  		u64_stats_update_end(&rx->sta->rx_stats.syncp);
  	}
  
  	if ((sdata->vif.type == NL80211_IFTYPE_AP ||
  	     sdata->vif.type == NL80211_IFTYPE_AP_VLAN) &&
  	    !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) &&
  	    ehdr->h_proto != rx->sdata->control_port_protocol &&
  	    (sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->u.vlan.sta)) {
  		if (is_multicast_ether_addr(ehdr->h_dest) &&
  		    ieee80211_vif_get_num_mcast_if(sdata) != 0) {
  			/*
  			 * send multicast frames both to higher layers in
  			 * local net stack and back to the wireless medium
  			 */
  			xmit_skb = skb_copy(skb, GFP_ATOMIC);
  			if (!xmit_skb)
  				net_info_ratelimited("%s: failed to clone multicast frame\n",
  						    dev->name);
  		} else if (!is_multicast_ether_addr(ehdr->h_dest) &&
  			   !ether_addr_equal(ehdr->h_dest, ehdr->h_source)) {
  			dsta = sta_info_get(sdata, ehdr->h_dest);
  			if (dsta) {
  				/*
  				 * The destination station is associated to
  				 * this AP (in this VLAN), so send the frame
  				 * directly to it and do not pass it to local
  				 * net stack.
  				 */
  				xmit_skb = skb;
  				skb = NULL;
  			}
  		}
  	}
  
  #ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
  	if (skb) {
  		/* 'align' will only take the values 0 or 2 here since all
  		 * frames are required to be aligned to 2-byte boundaries
  		 * when being passed to mac80211; the code here works just
  		 * as well if that isn't true, but mac80211 assumes it can
  		 * access fields as 2-byte aligned (e.g. for ether_addr_equal)
  		 */
  		int align;
  
  		align = (unsigned long)(skb->data + sizeof(struct ethhdr)) & 3;
  		if (align) {
  			if (WARN_ON(skb_headroom(skb) < 3)) {
  				dev_kfree_skb(skb);
  				skb = NULL;
  			} else {
  				u8 *data = skb->data;
  				size_t len = skb_headlen(skb);
  				skb->data -= align;
  				memmove(skb->data, data, len);
  				skb_set_tail_pointer(skb, len);
  			}
  		}
  	}
  #endif
  
  	if (skb) {
  		skb->protocol = eth_type_trans(skb, dev);
  		ieee80211_deliver_skb_to_local_stack(skb, rx);
  	}
  
  	if (xmit_skb) {
  		/*
  		 * Send to wireless media and increase priority by 256 to
  		 * keep the received priority instead of reclassifying
  		 * the frame (see cfg80211_classify8021d).
  		 */
  		xmit_skb->priority += 256;
  		xmit_skb->protocol = htons(ETH_P_802_3);
  		skb_reset_network_header(xmit_skb);
  		skb_reset_mac_header(xmit_skb);
  		dev_queue_xmit(xmit_skb);
  	}
  }
  
  static ieee80211_rx_result debug_noinline
  __ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx, u8 data_offset)
  {
  	struct net_device *dev = rx->sdata->dev;
  	struct sk_buff *skb = rx->skb;
  	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
  	__le16 fc = hdr->frame_control;
  	struct sk_buff_head frame_list;
  	struct ethhdr ethhdr;
  	const u8 *check_da = ethhdr.h_dest, *check_sa = ethhdr.h_source;
  
  	if (unlikely(ieee80211_has_a4(hdr->frame_control))) {
  		check_da = NULL;
  		check_sa = NULL;
  	} else switch (rx->sdata->vif.type) {
  		case NL80211_IFTYPE_AP:
  		case NL80211_IFTYPE_AP_VLAN:
  			check_da = NULL;
  			break;
  		case NL80211_IFTYPE_STATION:
  			if (!rx->sta ||
  			    !test_sta_flag(rx->sta, WLAN_STA_TDLS_PEER))
  				check_sa = NULL;
  			break;
  		case NL80211_IFTYPE_MESH_POINT:
  			check_sa = NULL;
  			break;
  		default:
  			break;
  	}
  
  	skb->dev = dev;
  	__skb_queue_head_init(&frame_list);
  
  	if (ieee80211_data_to_8023_exthdr(skb, &ethhdr,
  					  rx->sdata->vif.addr,
  					  rx->sdata->vif.type,
  					  data_offset, true))
  		return RX_DROP_UNUSABLE;
  
  	ieee80211_amsdu_to_8023s(skb, &frame_list, dev->dev_addr,
  				 rx->sdata->vif.type,
  				 rx->local->hw.extra_tx_headroom,
  				 check_da, check_sa);
  
  	while (!skb_queue_empty(&frame_list)) {
  		rx->skb = __skb_dequeue(&frame_list);
  
  		if (!ieee80211_frame_allowed(rx, fc)) {
  			dev_kfree_skb(rx->skb);
  			continue;
  		}
  
  		ieee80211_deliver_skb(rx);
  	}
  
  	return RX_QUEUED;
  }
  
  static ieee80211_rx_result debug_noinline
  ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx)
  {
  	struct sk_buff *skb = rx->skb;
  	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
  	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
  	__le16 fc = hdr->frame_control;
  
  	if (!(status->rx_flags & IEEE80211_RX_AMSDU))
  		return RX_CONTINUE;
  
  	if (unlikely(!ieee80211_is_data(fc)))
  		return RX_CONTINUE;
  
  	if (unlikely(!ieee80211_is_data_present(fc)))
  		return RX_DROP_MONITOR;
  
  	if (unlikely(ieee80211_has_a4(hdr->frame_control))) {
  		switch (rx->sdata->vif.type) {
  		case NL80211_IFTYPE_AP_VLAN:
  			if (!rx->sdata->u.vlan.sta)
  				return RX_DROP_UNUSABLE;
  			break;
  		case NL80211_IFTYPE_STATION:
  			if (!rx->sdata->u.mgd.use_4addr)
  				return RX_DROP_UNUSABLE;
  			break;
  		default:
  			return RX_DROP_UNUSABLE;
  		}
  	}
  
  	if (is_multicast_ether_addr(hdr->addr1))
  		return RX_DROP_UNUSABLE;
  
  	if (rx->key) {
  		/*
  		 * We should not receive A-MSDUs on pre-HT connections,
  		 * and HT connections cannot use old ciphers. Thus drop
  		 * them, as in those cases we couldn't even have SPP
  		 * A-MSDUs or such.
  		 */
  		switch (rx->key->conf.cipher) {
  		case WLAN_CIPHER_SUITE_WEP40:
  		case WLAN_CIPHER_SUITE_WEP104:
  		case WLAN_CIPHER_SUITE_TKIP:
  			return RX_DROP_UNUSABLE;
  		default:
  			break;
  		}
  	}
  
  	return __ieee80211_rx_h_amsdu(rx, 0);
  }
  
  #ifdef CONFIG_MAC80211_MESH
  static ieee80211_rx_result
  ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx)
  {
  	struct ieee80211_hdr *fwd_hdr, *hdr;
  	struct ieee80211_tx_info *info;
  	struct ieee80211s_hdr *mesh_hdr;
  	struct sk_buff *skb = rx->skb, *fwd_skb;
  	struct ieee80211_local *local = rx->local;
  	struct ieee80211_sub_if_data *sdata = rx->sdata;
  	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
  	u16 ac, q, hdrlen;
  	int tailroom = 0;
  
  	hdr = (struct ieee80211_hdr *) skb->data;
  	hdrlen = ieee80211_hdrlen(hdr->frame_control);
  
  	/* make sure fixed part of mesh header is there, also checks skb len */
  	if (!pskb_may_pull(rx->skb, hdrlen + 6))
  		return RX_DROP_MONITOR;
  
  	mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
  
  	/* make sure full mesh header is there, also checks skb len */
  	if (!pskb_may_pull(rx->skb,
  			   hdrlen + ieee80211_get_mesh_hdrlen(mesh_hdr)))
  		return RX_DROP_MONITOR;
  
  	/* reload pointers */
  	hdr = (struct ieee80211_hdr *) skb->data;
  	mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
  
  	if (ieee80211_drop_unencrypted(rx, hdr->frame_control))
  		return RX_DROP_MONITOR;
  
  	/* frame is in RMC, don't forward */
  	if (ieee80211_is_data(hdr->frame_control) &&
  	    is_multicast_ether_addr(hdr->addr1) &&
  	    mesh_rmc_check(rx->sdata, hdr->addr3, mesh_hdr))
  		return RX_DROP_MONITOR;
  
  	if (!ieee80211_is_data(hdr->frame_control))
  		return RX_CONTINUE;
  
  	if (!mesh_hdr->ttl)
  		return RX_DROP_MONITOR;
  
  	if (mesh_hdr->flags & MESH_FLAGS_AE) {
  		struct mesh_path *mppath;
  		char *proxied_addr;
  		char *mpp_addr;
  
  		if (is_multicast_ether_addr(hdr->addr1)) {
  			mpp_addr = hdr->addr3;
  			proxied_addr = mesh_hdr->eaddr1;
  		} else if ((mesh_hdr->flags & MESH_FLAGS_AE) ==
  			    MESH_FLAGS_AE_A5_A6) {
  			/* has_a4 already checked in ieee80211_rx_mesh_check */
  			mpp_addr = hdr->addr4;
  			proxied_addr = mesh_hdr->eaddr2;
  		} else {
  			return RX_DROP_MONITOR;
  		}
  
  		rcu_read_lock();
  		mppath = mpp_path_lookup(sdata, proxied_addr);
  		if (!mppath) {
  			mpp_path_add(sdata, proxied_addr, mpp_addr);
  		} else {
  			spin_lock_bh(&mppath->state_lock);
  			if (!ether_addr_equal(mppath->mpp, mpp_addr))
  				memcpy(mppath->mpp, mpp_addr, ETH_ALEN);
  			mppath->exp_time = jiffies;
  			spin_unlock_bh(&mppath->state_lock);
  		}
  		rcu_read_unlock();
  	}
  
  	/* Frame has reached destination.  Don't forward */
  	if (!is_multicast_ether_addr(hdr->addr1) &&
  	    ether_addr_equal(sdata->vif.addr, hdr->addr3))
  		return RX_CONTINUE;
  
  	ac = ieee80211_select_queue_80211(sdata, skb, hdr);
  	q = sdata->vif.hw_queue[ac];
  	if (ieee80211_queue_stopped(&local->hw, q)) {
  		IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_congestion);
  		return RX_DROP_MONITOR;
  	}
  	skb_set_queue_mapping(skb, q);
  
  	if (!--mesh_hdr->ttl) {
  		if (!is_multicast_ether_addr(hdr->addr1))
  			IEEE80211_IFSTA_MESH_CTR_INC(ifmsh,
  						     dropped_frames_ttl);
  		goto out;
  	}
  
  	if (!ifmsh->mshcfg.dot11MeshForwarding)
  		goto out;
  
  	if (sdata->crypto_tx_tailroom_needed_cnt)
  		tailroom = IEEE80211_ENCRYPT_TAILROOM;
  
  	fwd_skb = skb_copy_expand(skb, local->tx_headroom +
  				       sdata->encrypt_headroom,
  				  tailroom, GFP_ATOMIC);
  	if (!fwd_skb)
  		goto out;
  
  	fwd_hdr =  (struct ieee80211_hdr *) fwd_skb->data;
  	fwd_hdr->frame_control &= ~cpu_to_le16(IEEE80211_FCTL_RETRY);
  	info = IEEE80211_SKB_CB(fwd_skb);
  	memset(info, 0, sizeof(*info));
  	info->control.flags |= IEEE80211_TX_INTCFL_NEED_TXPROCESSING;
  	info->control.vif = &rx->sdata->vif;
  	info->control.jiffies = jiffies;
  	if (is_multicast_ether_addr(fwd_hdr->addr1)) {
  		IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_mcast);
  		memcpy(fwd_hdr->addr2, sdata->vif.addr, ETH_ALEN);
  		/* update power mode indication when forwarding */
  		ieee80211_mps_set_frame_flags(sdata, NULL, fwd_hdr);
  	} else if (!mesh_nexthop_lookup(sdata, fwd_skb)) {
  		/* mesh power mode flags updated in mesh_nexthop_lookup */
  		IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_unicast);
  	} else {
  		/* unable to resolve next hop */
  		mesh_path_error_tx(sdata, ifmsh->mshcfg.element_ttl,
  				   fwd_hdr->addr3, 0,
  				   WLAN_REASON_MESH_PATH_NOFORWARD,
  				   fwd_hdr->addr2);
  		IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_no_route);
  		kfree_skb(fwd_skb);
  		return RX_DROP_MONITOR;
  	}
  
  	IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_frames);
  	ieee80211_add_pending_skb(local, fwd_skb);
   out:
  	if (is_multicast_ether_addr(hdr->addr1))
  		return RX_CONTINUE;
  	return RX_DROP_MONITOR;
  }
  #endif
  
  static ieee80211_rx_result debug_noinline
  ieee80211_rx_h_data(struct ieee80211_rx_data *rx)
  {
  	struct ieee80211_sub_if_data *sdata = rx->sdata;
  	struct ieee80211_local *local = rx->local;
  	struct net_device *dev = sdata->dev;
  	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
  	__le16 fc = hdr->frame_control;
  	bool port_control;
  	int err;
  
  	if (unlikely(!ieee80211_is_data(hdr->frame_control)))
  		return RX_CONTINUE;
  
  	if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
  		return RX_DROP_MONITOR;
  
  	/*
  	 * Send unexpected-4addr-frame event to hostapd. For older versions,
  	 * also drop the frame to cooked monitor interfaces.
  	 */
  	if (ieee80211_has_a4(hdr->frame_control) &&
  	    sdata->vif.type == NL80211_IFTYPE_AP) {
  		if (rx->sta &&
  		    !test_and_set_sta_flag(rx->sta, WLAN_STA_4ADDR_EVENT))
  			cfg80211_rx_unexpected_4addr_frame(
  				rx->sdata->dev, rx->sta->sta.addr, GFP_ATOMIC);
  		return RX_DROP_MONITOR;
  	}
  
  	err = __ieee80211_data_to_8023(rx, &port_control);
  	if (unlikely(err))
  		return RX_DROP_UNUSABLE;
  
  	if (!ieee80211_frame_allowed(rx, fc))
  		return RX_DROP_MONITOR;
  
  	/* directly handle TDLS channel switch requests/responses */
  	if (unlikely(((struct ethhdr *)rx->skb->data)->h_proto ==
  						cpu_to_be16(ETH_P_TDLS))) {
  		struct ieee80211_tdls_data *tf = (void *)rx->skb->data;
  
  		if (pskb_may_pull(rx->skb,
  				  offsetof(struct ieee80211_tdls_data, u)) &&
  		    tf->payload_type == WLAN_TDLS_SNAP_RFTYPE &&
  		    tf->category == WLAN_CATEGORY_TDLS &&
  		    (tf->action_code == WLAN_TDLS_CHANNEL_SWITCH_REQUEST ||
  		     tf->action_code == WLAN_TDLS_CHANNEL_SWITCH_RESPONSE)) {
  			skb_queue_tail(&local->skb_queue_tdls_chsw, rx->skb);
  			schedule_work(&local->tdls_chsw_work);
  			if (rx->sta)
  				rx->sta->rx_stats.packets++;
  
  			return RX_QUEUED;
  		}
  	}
  
  	if (rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
  	    unlikely(port_control) && sdata->bss) {
  		sdata = container_of(sdata->bss, struct ieee80211_sub_if_data,
  				     u.ap);
  		dev = sdata->dev;
  		rx->sdata = sdata;
  	}
  
  	rx->skb->dev = dev;
  
  	if (!ieee80211_hw_check(&local->hw, SUPPORTS_DYNAMIC_PS) &&
  	    local->ps_sdata && local->hw.conf.dynamic_ps_timeout > 0 &&
  	    !is_multicast_ether_addr(
  		    ((struct ethhdr *)rx->skb->data)->h_dest) &&
  	    (!local->scanning &&
  	     !test_bit(SDATA_STATE_OFFCHANNEL, &sdata->state)))
  		mod_timer(&local->dynamic_ps_timer, jiffies +
  			  msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout));
  
  	ieee80211_deliver_skb(rx);
  
  	return RX_QUEUED;
  }
  
  static ieee80211_rx_result debug_noinline
  ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx, struct sk_buff_head *frames)
  {
  	struct sk_buff *skb = rx->skb;
  	struct ieee80211_bar *bar = (struct ieee80211_bar *)skb->data;
  	struct tid_ampdu_rx *tid_agg_rx;
  	u16 start_seq_num;
  	u16 tid;
  
  	if (likely(!ieee80211_is_ctl(bar->frame_control)))
  		return RX_CONTINUE;
  
  	if (ieee80211_is_back_req(bar->frame_control)) {
  		struct {
  			__le16 control, start_seq_num;
  		} __packed bar_data;
  		struct ieee80211_event event = {
  			.type = BAR_RX_EVENT,
  		};
  
  		if (!rx->sta)
  			return RX_DROP_MONITOR;
  
  		if (skb_copy_bits(skb, offsetof(struct ieee80211_bar, control),
  				  &bar_data, sizeof(bar_data)))
  			return RX_DROP_MONITOR;
  
  		tid = le16_to_cpu(bar_data.control) >> 12;
  
  		if (!test_bit(tid, rx->sta->ampdu_mlme.agg_session_valid) &&
  		    !test_and_set_bit(tid, rx->sta->ampdu_mlme.unexpected_agg))
  			ieee80211_send_delba(rx->sdata, rx->sta->sta.addr, tid,
  					     WLAN_BACK_RECIPIENT,
  					     WLAN_REASON_QSTA_REQUIRE_SETUP);
  
  		tid_agg_rx = rcu_dereference(rx->sta->ampdu_mlme.tid_rx[tid]);
  		if (!tid_agg_rx)
  			return RX_DROP_MONITOR;
  
  		start_seq_num = le16_to_cpu(bar_data.start_seq_num) >> 4;
  		event.u.ba.tid = tid;
  		event.u.ba.ssn = start_seq_num;
  		event.u.ba.sta = &rx->sta->sta;
  
  		/* reset session timer */
  		if (tid_agg_rx->timeout)
  			mod_timer(&tid_agg_rx->session_timer,
  				  TU_TO_EXP_TIME(tid_agg_rx->timeout));
  
  		spin_lock(&tid_agg_rx->reorder_lock);
  		/* release stored frames up to start of BAR */
  		ieee80211_release_reorder_frames(rx->sdata, tid_agg_rx,
  						 start_seq_num, frames);
  		spin_unlock(&tid_agg_rx->reorder_lock);
  
  		drv_event_callback(rx->local, rx->sdata, &event);
  
  		kfree_skb(skb);
  		return RX_QUEUED;
  	}
  
  	/*
  	 * After this point, we only want management frames,
  	 * so we can drop all remaining control frames to
  	 * cooked monitor interfaces.
  	 */
  	return RX_DROP_MONITOR;
  }
  
  static void ieee80211_process_sa_query_req(struct ieee80211_sub_if_data *sdata,
  					   struct ieee80211_mgmt *mgmt,
  					   size_t len)
  {
  	struct ieee80211_local *local = sdata->local;
  	struct sk_buff *skb;
  	struct ieee80211_mgmt *resp;
  
  	if (!ether_addr_equal(mgmt->da, sdata->vif.addr)) {
  		/* Not to own unicast address */
  		return;
  	}
  
  	if (!ether_addr_equal(mgmt->sa, sdata->u.mgd.bssid) ||
  	    !ether_addr_equal(mgmt->bssid, sdata->u.mgd.bssid)) {
  		/* Not from the current AP or not associated yet. */
  		return;
  	}
  
  	if (len < 24 + 1 + sizeof(resp->u.action.u.sa_query)) {
  		/* Too short SA Query request frame */
  		return;
  	}
  
  	skb = dev_alloc_skb(sizeof(*resp) + local->hw.extra_tx_headroom);
  	if (skb == NULL)
  		return;
  
  	skb_reserve(skb, local->hw.extra_tx_headroom);
  	resp = skb_put_zero(skb, 24);
  	memcpy(resp->da, mgmt->sa, ETH_ALEN);
  	memcpy(resp->sa, sdata->vif.addr, ETH_ALEN);
  	memcpy(resp->bssid, sdata->u.mgd.bssid, ETH_ALEN);
  	resp->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
  					  IEEE80211_STYPE_ACTION);
  	skb_put(skb, 1 + sizeof(resp->u.action.u.sa_query));
  	resp->u.action.category = WLAN_CATEGORY_SA_QUERY;
  	resp->u.action.u.sa_query.action = WLAN_ACTION_SA_QUERY_RESPONSE;
  	memcpy(resp->u.action.u.sa_query.trans_id,
  	       mgmt->u.action.u.sa_query.trans_id,
  	       WLAN_SA_QUERY_TR_ID_LEN);
  
  	ieee80211_tx_skb(sdata, skb);
  }
  
  static ieee80211_rx_result debug_noinline
  ieee80211_rx_h_mgmt_check(struct ieee80211_rx_data *rx)
  {
  	struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
  	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
  
  	if (ieee80211_is_s1g_beacon(mgmt->frame_control))
  		return RX_CONTINUE;
  
  	/*
  	 * From here on, look only at management frames.
  	 * Data and control frames are already handled,
  	 * and unknown (reserved) frames are useless.
  	 */
  	if (rx->skb->len < 24)
  		return RX_DROP_MONITOR;
  
  	if (!ieee80211_is_mgmt(mgmt->frame_control))
  		return RX_DROP_MONITOR;
  
  	if (rx->sdata->vif.type == NL80211_IFTYPE_AP &&
  	    ieee80211_is_beacon(mgmt->frame_control) &&
  	    !(rx->flags & IEEE80211_RX_BEACON_REPORTED)) {
  		int sig = 0;
  
  		if (ieee80211_hw_check(&rx->local->hw, SIGNAL_DBM) &&
  		    !(status->flag & RX_FLAG_NO_SIGNAL_VAL))
  			sig = status->signal;
  
  		cfg80211_report_obss_beacon_khz(rx->local->hw.wiphy,
  						rx->skb->data, rx->skb->len,
  						ieee80211_rx_status_to_khz(status),
  						sig);
  		rx->flags |= IEEE80211_RX_BEACON_REPORTED;
  	}
  
  	if (ieee80211_drop_unencrypted_mgmt(rx))
  		return RX_DROP_UNUSABLE;
  
  	return RX_CONTINUE;
  }
  
  static ieee80211_rx_result debug_noinline
  ieee80211_rx_h_action(struct ieee80211_rx_data *rx)
  {
  	struct ieee80211_local *local = rx->local;
  	struct ieee80211_sub_if_data *sdata = rx->sdata;
  	struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
  	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
  	int len = rx->skb->len;
  
  	if (!ieee80211_is_action(mgmt->frame_control))
  		return RX_CONTINUE;
  
  	/* drop too small frames */
  	if (len < IEEE80211_MIN_ACTION_SIZE)
  		return RX_DROP_UNUSABLE;
  
  	if (!rx->sta && mgmt->u.action.category != WLAN_CATEGORY_PUBLIC &&
  	    mgmt->u.action.category != WLAN_CATEGORY_SELF_PROTECTED &&
  	    mgmt->u.action.category != WLAN_CATEGORY_SPECTRUM_MGMT)
  		return RX_DROP_UNUSABLE;
  
  	switch (mgmt->u.action.category) {
  	case WLAN_CATEGORY_HT:
  		/* reject HT action frames from stations not supporting HT */
  		if (!rx->sta->sta.ht_cap.ht_supported)
  			goto invalid;
  
  		if (sdata->vif.type != NL80211_IFTYPE_STATION &&
  		    sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
  		    sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
  		    sdata->vif.type != NL80211_IFTYPE_AP &&
  		    sdata->vif.type != NL80211_IFTYPE_ADHOC)
  			break;
  
  		/* verify action & smps_control/chanwidth are present */
  		if (len < IEEE80211_MIN_ACTION_SIZE + 2)
  			goto invalid;
  
  		switch (mgmt->u.action.u.ht_smps.action) {
  		case WLAN_HT_ACTION_SMPS: {
  			struct ieee80211_supported_band *sband;
  			enum ieee80211_smps_mode smps_mode;
  			struct sta_opmode_info sta_opmode = {};
  
  			if (sdata->vif.type != NL80211_IFTYPE_AP &&
  			    sdata->vif.type != NL80211_IFTYPE_AP_VLAN)
  				goto handled;
  
  			/* convert to HT capability */
  			switch (mgmt->u.action.u.ht_smps.smps_control) {
  			case WLAN_HT_SMPS_CONTROL_DISABLED:
  				smps_mode = IEEE80211_SMPS_OFF;
  				break;
  			case WLAN_HT_SMPS_CONTROL_STATIC:
  				smps_mode = IEEE80211_SMPS_STATIC;
  				break;
  			case WLAN_HT_SMPS_CONTROL_DYNAMIC:
  				smps_mode = IEEE80211_SMPS_DYNAMIC;
  				break;
  			default:
  				goto invalid;
  			}
  
  			/* if no change do nothing */
  			if (rx->sta->sta.smps_mode == smps_mode)
  				goto handled;
  			rx->sta->sta.smps_mode = smps_mode;
  			sta_opmode.smps_mode =
  				ieee80211_smps_mode_to_smps_mode(smps_mode);
  			sta_opmode.changed = STA_OPMODE_SMPS_MODE_CHANGED;
  
  			sband = rx->local->hw.wiphy->bands[status->band];
  
  			rate_control_rate_update(local, sband, rx->sta,
  						 IEEE80211_RC_SMPS_CHANGED);
  			cfg80211_sta_opmode_change_notify(sdata->dev,
  							  rx->sta->addr,
  							  &sta_opmode,
  							  GFP_ATOMIC);
  			goto handled;
  		}
  		case WLAN_HT_ACTION_NOTIFY_CHANWIDTH: {
  			struct ieee80211_supported_band *sband;
  			u8 chanwidth = mgmt->u.action.u.ht_notify_cw.chanwidth;
  			enum ieee80211_sta_rx_bandwidth max_bw, new_bw;
  			struct sta_opmode_info sta_opmode = {};
  
  			/* If it doesn't support 40 MHz it can't change ... */
  			if (!(rx->sta->sta.ht_cap.cap &
  					IEEE80211_HT_CAP_SUP_WIDTH_20_40))
  				goto handled;
  
  			if (chanwidth == IEEE80211_HT_CHANWIDTH_20MHZ)
  				max_bw = IEEE80211_STA_RX_BW_20;
  			else
  				max_bw = ieee80211_sta_cap_rx_bw(rx->sta);
  
  			/* set cur_max_bandwidth and recalc sta bw */
  			rx->sta->cur_max_bandwidth = max_bw;
  			new_bw = ieee80211_sta_cur_vht_bw(rx->sta);
  
  			if (rx->sta->sta.bandwidth == new_bw)
  				goto handled;
  
  			rx->sta->sta.bandwidth = new_bw;
  			sband = rx->local->hw.wiphy->bands[status->band];
  			sta_opmode.bw =
  				ieee80211_sta_rx_bw_to_chan_width(rx->sta);
  			sta_opmode.changed = STA_OPMODE_MAX_BW_CHANGED;
  
  			rate_control_rate_update(local, sband, rx->sta,
  						 IEEE80211_RC_BW_CHANGED);
  			cfg80211_sta_opmode_change_notify(sdata->dev,
  							  rx->sta->addr,
  							  &sta_opmode,
  							  GFP_ATOMIC);
  			goto handled;
  		}
  		default:
  			goto invalid;
  		}
  
  		break;
  	case WLAN_CATEGORY_PUBLIC:
  		if (len < IEEE80211_MIN_ACTION_SIZE + 1)
  			goto invalid;
  		if (sdata->vif.type != NL80211_IFTYPE_STATION)
  			break;
  		if (!rx->sta)
  			break;
  		if (!ether_addr_equal(mgmt->bssid, sdata->u.mgd.bssid))
  			break;
  		if (mgmt->u.action.u.ext_chan_switch.action_code !=
  				WLAN_PUB_ACTION_EXT_CHANSW_ANN)
  			break;
  		if (len < offsetof(struct ieee80211_mgmt,
  				   u.action.u.ext_chan_switch.variable))
  			goto invalid;
  		goto queue;
  	case WLAN_CATEGORY_VHT:
  		if (sdata->vif.type != NL80211_IFTYPE_STATION &&
  		    sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
  		    sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
  		    sdata->vif.type != NL80211_IFTYPE_AP &&
  		    sdata->vif.type != NL80211_IFTYPE_ADHOC)
  			break;
  
  		/* verify action code is present */
  		if (len < IEEE80211_MIN_ACTION_SIZE + 1)
  			goto invalid;
  
  		switch (mgmt->u.action.u.vht_opmode_notif.action_code) {
  		case WLAN_VHT_ACTION_OPMODE_NOTIF: {
  			/* verify opmode is present */
  			if (len < IEEE80211_MIN_ACTION_SIZE + 2)
  				goto invalid;
  			goto queue;
  		}
  		case WLAN_VHT_ACTION_GROUPID_MGMT: {
  			if (len < IEEE80211_MIN_ACTION_SIZE + 25)
  				goto invalid;
  			goto queue;
  		}
  		default:
  			break;
  		}
  		break;
  	case WLAN_CATEGORY_BACK:
  		if (sdata->vif.type != NL80211_IFTYPE_STATION &&
  		    sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
  		    sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
  		    sdata->vif.type != NL80211_IFTYPE_AP &&
  		    sdata->vif.type != NL80211_IFTYPE_ADHOC)
  			break;
  
  		/* verify action_code is present */
  		if (len < IEEE80211_MIN_ACTION_SIZE + 1)
  			break;
  
  		switch (mgmt->u.action.u.addba_req.action_code) {
  		case WLAN_ACTION_ADDBA_REQ:
  			if (len < (IEEE80211_MIN_ACTION_SIZE +
  				   sizeof(mgmt->u.action.u.addba_req)))
  				goto invalid;
  			break;
  		case WLAN_ACTION_ADDBA_RESP:
  			if (len < (IEEE80211_MIN_ACTION_SIZE +
  				   sizeof(mgmt->u.action.u.addba_resp)))
  				goto invalid;
  			break;
  		case WLAN_ACTION_DELBA:
  			if (len < (IEEE80211_MIN_ACTION_SIZE +
  				   sizeof(mgmt->u.action.u.delba)))
  				goto invalid;
  			break;
  		default:
  			goto invalid;
  		}
  
  		goto queue;
  	case WLAN_CATEGORY_SPECTRUM_MGMT:
  		/* verify action_code is present */
  		if (len < IEEE80211_MIN_ACTION_SIZE + 1)
  			break;
  
  		switch (mgmt->u.action.u.measurement.action_code) {
  		case WLAN_ACTION_SPCT_MSR_REQ:
  			if (status->band != NL80211_BAND_5GHZ)
  				break;
  
  			if (len < (IEEE80211_MIN_ACTION_SIZE +
  				   sizeof(mgmt->u.action.u.measurement)))
  				break;
  
  			if (sdata->vif.type != NL80211_IFTYPE_STATION)
  				break;
  
  			ieee80211_process_measurement_req(sdata, mgmt, len);
  			goto handled;
  		case WLAN_ACTION_SPCT_CHL_SWITCH: {
  			u8 *bssid;
  			if (len < (IEEE80211_MIN_ACTION_SIZE +
  				   sizeof(mgmt->u.action.u.chan_switch)))
  				break;
  
  			if (sdata->vif.type != NL80211_IFTYPE_STATION &&
  			    sdata->vif.type != NL80211_IFTYPE_ADHOC &&
  			    sdata->vif.type != NL80211_IFTYPE_MESH_POINT)
  				break;
  
  			if (sdata->vif.type == NL80211_IFTYPE_STATION)
  				bssid = sdata->u.mgd.bssid;
  			else if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
  				bssid = sdata->u.ibss.bssid;
  			else if (sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
  				bssid = mgmt->sa;
  			else
  				break;
  
  			if (!ether_addr_equal(mgmt->bssid, bssid))
  				break;
  
  			goto queue;
  			}
  		}
  		break;
  	case WLAN_CATEGORY_SELF_PROTECTED:
  		if (len < (IEEE80211_MIN_ACTION_SIZE +
  			   sizeof(mgmt->u.action.u.self_prot.action_code)))
  			break;
  
  		switch (mgmt->u.action.u.self_prot.action_code) {
  		case WLAN_SP_MESH_PEERING_OPEN:
  		case WLAN_SP_MESH_PEERING_CLOSE:
  		case WLAN_SP_MESH_PEERING_CONFIRM:
  			if (!ieee80211_vif_is_mesh(&sdata->vif))
  				goto invalid;
  			if (sdata->u.mesh.user_mpm)
  				/* userspace handles this frame */
  				break;
  			goto queue;
  		case WLAN_SP_MGK_INFORM:
  		case WLAN_SP_MGK_ACK:
  			if (!ieee80211_vif_is_mesh(&sdata->vif))
  				goto invalid;
  			break;
  		}
  		break;
  	case WLAN_CATEGORY_MESH_ACTION:
  		if (len < (IEEE80211_MIN_ACTION_SIZE +
  			   sizeof(mgmt->u.action.u.mesh_action.action_code)))
  			break;
  
  		if (!ieee80211_vif_is_mesh(&sdata->vif))
  			break;
  		if (mesh_action_is_path_sel(mgmt) &&
  		    !mesh_path_sel_is_hwmp(sdata))
  			break;
  		goto queue;
  	}
  
  	return RX_CONTINUE;
  
   invalid:
  	status->rx_flags |= IEEE80211_RX_MALFORMED_ACTION_FRM;
  	/* will return in the next handlers */
  	return RX_CONTINUE;
  
   handled:
  	if (rx->sta)
  		rx->sta->rx_stats.packets++;
  	dev_kfree_skb(rx->skb);
  	return RX_QUEUED;
  
   queue:
  	skb_queue_tail(&sdata->skb_queue, rx->skb);
  	ieee80211_queue_work(&local->hw, &sdata->work);
  	if (rx->sta)
  		rx->sta->rx_stats.packets++;
  	return RX_QUEUED;
  }
  
  static ieee80211_rx_result debug_noinline
  ieee80211_rx_h_userspace_mgmt(struct ieee80211_rx_data *rx)
  {
  	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
  	int sig = 0;
  
  	/* skip known-bad action frames and return them in the next handler */
  	if (status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM)
  		return RX_CONTINUE;
  
  	/*
  	 * Getting here means the kernel doesn't know how to handle
  	 * it, but maybe userspace does ... include returned frames
  	 * so userspace can register for those to know whether ones
  	 * it transmitted were processed or returned.
  	 */
  
  	if (ieee80211_hw_check(&rx->local->hw, SIGNAL_DBM) &&
  	    !(status->flag & RX_FLAG_NO_SIGNAL_VAL))
  		sig = status->signal;
  
  	if (cfg80211_rx_mgmt_khz(&rx->sdata->wdev,
  				 ieee80211_rx_status_to_khz(status), sig,
  				 rx->skb->data, rx->skb->len, 0)) {
  		if (rx->sta)
  			rx->sta->rx_stats.packets++;
  		dev_kfree_skb(rx->skb);
  		return RX_QUEUED;
  	}
  
  	return RX_CONTINUE;
  }
  
  static ieee80211_rx_result debug_noinline
  ieee80211_rx_h_action_post_userspace(struct ieee80211_rx_data *rx)
  {
  	struct ieee80211_sub_if_data *sdata = rx->sdata;
  	struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
  	int len = rx->skb->len;
  
  	if (!ieee80211_is_action(mgmt->frame_control))
  		return RX_CONTINUE;
  
  	switch (mgmt->u.action.category) {
  	case WLAN_CATEGORY_SA_QUERY:
  		if (len < (IEEE80211_MIN_ACTION_SIZE +
  			   sizeof(mgmt->u.action.u.sa_query)))
  			break;
  
  		switch (mgmt->u.action.u.sa_query.action) {
  		case WLAN_ACTION_SA_QUERY_REQUEST:
  			if (sdata->vif.type != NL80211_IFTYPE_STATION)
  				break;
  			ieee80211_process_sa_query_req(sdata, mgmt, len);
  			goto handled;
  		}
  		break;
  	}
  
  	return RX_CONTINUE;
  
   handled:
  	if (rx->sta)
  		rx->sta->rx_stats.packets++;
  	dev_kfree_skb(rx->skb);
  	return RX_QUEUED;
  }
  
  static ieee80211_rx_result debug_noinline
  ieee80211_rx_h_action_return(struct ieee80211_rx_data *rx)
  {
  	struct ieee80211_local *local = rx->local;
  	struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
  	struct sk_buff *nskb;
  	struct ieee80211_sub_if_data *sdata = rx->sdata;
  	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
  
  	if (!ieee80211_is_action(mgmt->frame_control))
  		return RX_CONTINUE;
  
  	/*
  	 * For AP mode, hostapd is responsible for handling any action
  	 * frames that we didn't handle, including returning unknown
  	 * ones. For all other modes we will return them to the sender,
  	 * setting the 0x80 bit in the action category, as required by
  	 * 802.11-2012 9.24.4.
  	 * Newer versions of hostapd shall also use the management frame
  	 * registration mechanisms, but older ones still use cooked
  	 * monitor interfaces so push all frames there.
  	 */
  	if (!(status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM) &&
  	    (sdata->vif.type == NL80211_IFTYPE_AP ||
  	     sdata->vif.type == NL80211_IFTYPE_AP_VLAN))
  		return RX_DROP_MONITOR;
  
  	if (is_multicast_ether_addr(mgmt->da))
  		return RX_DROP_MONITOR;
  
  	/* do not return rejected action frames */
  	if (mgmt->u.action.category & 0x80)
  		return RX_DROP_UNUSABLE;
  
  	nskb = skb_copy_expand(rx->skb, local->hw.extra_tx_headroom, 0,
  			       GFP_ATOMIC);
  	if (nskb) {
  		struct ieee80211_mgmt *nmgmt = (void *)nskb->data;
  
  		nmgmt->u.action.category |= 0x80;
  		memcpy(nmgmt->da, nmgmt->sa, ETH_ALEN);
  		memcpy(nmgmt->sa, rx->sdata->vif.addr, ETH_ALEN);
  
  		memset(nskb->cb, 0, sizeof(nskb->cb));
  
  		if (rx->sdata->vif.type == NL80211_IFTYPE_P2P_DEVICE) {
  			struct ieee80211_tx_info *info = IEEE80211_SKB_CB(nskb);
  
  			info->flags = IEEE80211_TX_CTL_TX_OFFCHAN |
  				      IEEE80211_TX_INTFL_OFFCHAN_TX_OK |
  				      IEEE80211_TX_CTL_NO_CCK_RATE;
  			if (ieee80211_hw_check(&local->hw, QUEUE_CONTROL))
  				info->hw_queue =
  					local->hw.offchannel_tx_hw_queue;
  		}
  
  		__ieee80211_tx_skb_tid_band(rx->sdata, nskb, 7,
  					    status->band);
  	}
  	dev_kfree_skb(rx->skb);
  	return RX_QUEUED;
  }
  
  static ieee80211_rx_result debug_noinline
  ieee80211_rx_h_ext(struct ieee80211_rx_data *rx)
  {
  	struct ieee80211_sub_if_data *sdata = rx->sdata;
  	struct ieee80211_hdr *hdr = (void *)rx->skb->data;
  
  	if (!ieee80211_is_ext(hdr->frame_control))
  		return RX_CONTINUE;
  
  	if (sdata->vif.type != NL80211_IFTYPE_STATION)
  		return RX_DROP_MONITOR;
  
  	/* for now only beacons are ext, so queue them */
  	skb_queue_tail(&sdata->skb_queue, rx->skb);
  	ieee80211_queue_work(&rx->local->hw, &sdata->work);
  	if (rx->sta)
  		rx->sta->rx_stats.packets++;
  
  	return RX_QUEUED;
  }
  
  static ieee80211_rx_result debug_noinline
  ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx)
  {
  	struct ieee80211_sub_if_data *sdata = rx->sdata;
  	struct ieee80211_mgmt *mgmt = (void *)rx->skb->data;
  	__le16 stype;
  
  	stype = mgmt->frame_control & cpu_to_le16(IEEE80211_FCTL_STYPE);
  
  	if (!ieee80211_vif_is_mesh(&sdata->vif) &&
  	    sdata->vif.type != NL80211_IFTYPE_ADHOC &&
  	    sdata->vif.type != NL80211_IFTYPE_OCB &&
  	    sdata->vif.type != NL80211_IFTYPE_STATION)
  		return RX_DROP_MONITOR;
  
  	switch (stype) {
  	case cpu_to_le16(IEEE80211_STYPE_AUTH):
  	case cpu_to_le16(IEEE80211_STYPE_BEACON):
  	case cpu_to_le16(IEEE80211_STYPE_PROBE_RESP):
  		/* process for all: mesh, mlme, ibss */
  		break;
  	case cpu_to_le16(IEEE80211_STYPE_DEAUTH):
  		if (is_multicast_ether_addr(mgmt->da) &&
  		    !is_broadcast_ether_addr(mgmt->da))
  			return RX_DROP_MONITOR;
  
  		/* process only for station/IBSS */
  		if (sdata->vif.type != NL80211_IFTYPE_STATION &&
  		    sdata->vif.type != NL80211_IFTYPE_ADHOC)
  			return RX_DROP_MONITOR;
  		break;
  	case cpu_to_le16(IEEE80211_STYPE_ASSOC_RESP):
  	case cpu_to_le16(IEEE80211_STYPE_REASSOC_RESP):
  	case cpu_to_le16(IEEE80211_STYPE_DISASSOC):
  		if (is_multicast_ether_addr(mgmt->da) &&
  		    !is_broadcast_ether_addr(mgmt->da))
  			return RX_DROP_MONITOR;
  
  		/* process only for station */
  		if (sdata->vif.type != NL80211_IFTYPE_STATION)
  			return RX_DROP_MONITOR;
  		break;
  	case cpu_to_le16(IEEE80211_STYPE_PROBE_REQ):
  		/* process only for ibss and mesh */
  		if (sdata->vif.type != NL80211_IFTYPE_ADHOC &&
  		    sdata->vif.type != NL80211_IFTYPE_MESH_POINT)
  			return RX_DROP_MONITOR;
  		break;
  	default:
  		return RX_DROP_MONITOR;
  	}
  
  	/* queue up frame and kick off work to process it */
  	skb_queue_tail(&sdata->skb_queue, rx->skb);
  	ieee80211_queue_work(&rx->local->hw, &sdata->work);
  	if (rx->sta)
  		rx->sta->rx_stats.packets++;
  
  	return RX_QUEUED;
  }
  
  static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx,
  					struct ieee80211_rate *rate)
  {
  	struct ieee80211_sub_if_data *sdata;
  	struct ieee80211_local *local = rx->local;
  	struct sk_buff *skb = rx->skb, *skb2;
  	struct net_device *prev_dev = NULL;
  	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
  	int needed_headroom;
  
  	/*
  	 * If cooked monitor has been processed already, then
  	 * don't do it again. If not, set the flag.
  	 */
  	if (rx->flags & IEEE80211_RX_CMNTR)
  		goto out_free_skb;
  	rx->flags |= IEEE80211_RX_CMNTR;
  
  	/* If there are no cooked monitor interfaces, just free the SKB */
  	if (!local->cooked_mntrs)
  		goto out_free_skb;
  
  	/* vendor data is long removed here */
  	status->flag &= ~RX_FLAG_RADIOTAP_VENDOR_DATA;
  	/* room for the radiotap header based on driver features */
  	needed_headroom = ieee80211_rx_radiotap_hdrlen(local, status, skb);
  
  	if (skb_headroom(skb) < needed_headroom &&
  	    pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC))
  		goto out_free_skb;
  
  	/* prepend radiotap information */
  	ieee80211_add_rx_radiotap_header(local, skb, rate, needed_headroom,
  					 false);
  
  	skb_reset_mac_header(skb);
  	skb->ip_summed = CHECKSUM_UNNECESSARY;
  	skb->pkt_type = PACKET_OTHERHOST;
  	skb->protocol = htons(ETH_P_802_2);
  
  	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
  		if (!ieee80211_sdata_running(sdata))
  			continue;
  
  		if (sdata->vif.type != NL80211_IFTYPE_MONITOR ||
  		    !(sdata->u.mntr.flags & MONITOR_FLAG_COOK_FRAMES))
  			continue;
  
  		if (prev_dev) {
  			skb2 = skb_clone(skb, GFP_ATOMIC);
  			if (skb2) {
  				skb2->dev = prev_dev;
  				netif_receive_skb(skb2);
  			}
  		}
  
  		prev_dev = sdata->dev;
  		ieee80211_rx_stats(sdata->dev, skb->len);
  	}
  
  	if (prev_dev) {
  		skb->dev = prev_dev;
  		netif_receive_skb(skb);
  		return;
  	}
  
   out_free_skb:
  	dev_kfree_skb(skb);
  }
  
  static void ieee80211_rx_handlers_result(struct ieee80211_rx_data *rx,
  					 ieee80211_rx_result res)
  {
  	switch (res) {
  	case RX_DROP_MONITOR:
  		I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop);
  		if (rx->sta)
  			rx->sta->rx_stats.dropped++;
  		fallthrough;
  	case RX_CONTINUE: {
  		struct ieee80211_rate *rate = NULL;
  		struct ieee80211_supported_band *sband;
  		struct ieee80211_rx_status *status;
  
  		status = IEEE80211_SKB_RXCB((rx->skb));
  
  		sband = rx->local->hw.wiphy->bands[status->band];
  		if (status->encoding == RX_ENC_LEGACY)
  			rate = &sband->bitrates[status->rate_idx];
  
  		ieee80211_rx_cooked_monitor(rx, rate);
  		break;
  		}
  	case RX_DROP_UNUSABLE:
  		I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop);
  		if (rx->sta)
  			rx->sta->rx_stats.dropped++;
  		dev_kfree_skb(rx->skb);
  		break;
  	case RX_QUEUED:
  		I802_DEBUG_INC(rx->sdata->local->rx_handlers_queued);
  		break;
  	}
  }
  
  static void ieee80211_rx_handlers(struct ieee80211_rx_data *rx,
  				  struct sk_buff_head *frames)
  {
  	ieee80211_rx_result res = RX_DROP_MONITOR;
  	struct sk_buff *skb;
  
  #define CALL_RXH(rxh)			\
  	do {				\
  		res = rxh(rx);		\
  		if (res != RX_CONTINUE)	\
  			goto rxh_next;  \
  	} while (0)
  
  	/* Lock here to avoid hitting all of the data used in the RX
  	 * path (e.g. key data, station data, ...) concurrently when
  	 * a frame is released from the reorder buffer due to timeout
  	 * from the timer, potentially concurrently with RX from the
  	 * driver.
  	 */
  	spin_lock_bh(&rx->local->rx_path_lock);
  
  	while ((skb = __skb_dequeue(frames))) {
  		/*
  		 * all the other fields are valid across frames
  		 * that belong to an aMPDU since they are on the
  		 * same TID from the same station
  		 */
  		rx->skb = skb;
  
  		CALL_RXH(ieee80211_rx_h_check_more_data);
  		CALL_RXH(ieee80211_rx_h_uapsd_and_pspoll);
  		CALL_RXH(ieee80211_rx_h_sta_process);
  		CALL_RXH(ieee80211_rx_h_decrypt);
  		CALL_RXH(ieee80211_rx_h_defragment);
  		CALL_RXH(ieee80211_rx_h_michael_mic_verify);
  		/* must be after MMIC verify so header is counted in MPDU mic */
  #ifdef CONFIG_MAC80211_MESH
  		if (ieee80211_vif_is_mesh(&rx->sdata->vif))
  			CALL_RXH(ieee80211_rx_h_mesh_fwding);
  #endif
  		CALL_RXH(ieee80211_rx_h_amsdu);
  		CALL_RXH(ieee80211_rx_h_data);
  
  		/* special treatment -- needs the queue */
  		res = ieee80211_rx_h_ctrl(rx, frames);
  		if (res != RX_CONTINUE)
  			goto rxh_next;
  
  		CALL_RXH(ieee80211_rx_h_mgmt_check);
  		CALL_RXH(ieee80211_rx_h_action);
  		CALL_RXH(ieee80211_rx_h_userspace_mgmt);
  		CALL_RXH(ieee80211_rx_h_action_post_userspace);
  		CALL_RXH(ieee80211_rx_h_action_return);
  		CALL_RXH(ieee80211_rx_h_ext);
  		CALL_RXH(ieee80211_rx_h_mgmt);
  
   rxh_next:
  		ieee80211_rx_handlers_result(rx, res);
  
  #undef CALL_RXH
  	}
  
  	spin_unlock_bh(&rx->local->rx_path_lock);
  }
  
  static void ieee80211_invoke_rx_handlers(struct ieee80211_rx_data *rx)
  {
  	struct sk_buff_head reorder_release;
  	ieee80211_rx_result res = RX_DROP_MONITOR;
  
  	__skb_queue_head_init(&reorder_release);
  
  #define CALL_RXH(rxh)			\
  	do {				\
  		res = rxh(rx);		\
  		if (res != RX_CONTINUE)	\
  			goto rxh_next;  \
  	} while (0)
  
  	CALL_RXH(ieee80211_rx_h_check_dup);
  	CALL_RXH(ieee80211_rx_h_check);
  
  	ieee80211_rx_reorder_ampdu(rx, &reorder_release);
  
  	ieee80211_rx_handlers(rx, &reorder_release);
  	return;
  
   rxh_next:
  	ieee80211_rx_handlers_result(rx, res);
  
  #undef CALL_RXH
  }
  
  /*
   * This function makes calls into the RX path, therefore
   * it has to be invoked under RCU read lock.
   */
  void ieee80211_release_reorder_timeout(struct sta_info *sta, int tid)
  {
  	struct sk_buff_head frames;
  	struct ieee80211_rx_data rx = {
  		.sta = sta,
  		.sdata = sta->sdata,
  		.local = sta->local,
  		/* This is OK -- must be QoS data frame */
  		.security_idx = tid,
  		.seqno_idx = tid,
  	};
  	struct tid_ampdu_rx *tid_agg_rx;
  
  	tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
  	if (!tid_agg_rx)
  		return;
  
  	__skb_queue_head_init(&frames);
  
  	spin_lock(&tid_agg_rx->reorder_lock);
  	ieee80211_sta_reorder_release(sta->sdata, tid_agg_rx, &frames);
  	spin_unlock(&tid_agg_rx->reorder_lock);
  
  	if (!skb_queue_empty(&frames)) {
  		struct ieee80211_event event = {
  			.type = BA_FRAME_TIMEOUT,
  			.u.ba.tid = tid,
  			.u.ba.sta = &sta->sta,
  		};
  		drv_event_callback(rx.local, rx.sdata, &event);
  	}
  
  	ieee80211_rx_handlers(&rx, &frames);
  }
  
  void ieee80211_mark_rx_ba_filtered_frames(struct ieee80211_sta *pubsta, u8 tid,
  					  u16 ssn, u64 filtered,
  					  u16 received_mpdus)
  {
  	struct sta_info *sta;
  	struct tid_ampdu_rx *tid_agg_rx;
  	struct sk_buff_head frames;
  	struct ieee80211_rx_data rx = {
  		/* This is OK -- must be QoS data frame */
  		.security_idx = tid,
  		.seqno_idx = tid,
  	};
  	int i, diff;
  
  	if (WARN_ON(!pubsta || tid >= IEEE80211_NUM_TIDS))
  		return;
  
  	__skb_queue_head_init(&frames);
  
  	sta = container_of(pubsta, struct sta_info, sta);
  
  	rx.sta = sta;
  	rx.sdata = sta->sdata;
  	rx.local = sta->local;
  
  	rcu_read_lock();
  	tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
  	if (!tid_agg_rx)
  		goto out;
  
  	spin_lock_bh(&tid_agg_rx->reorder_lock);
  
  	if (received_mpdus >= IEEE80211_SN_MODULO >> 1) {
  		int release;
  
  		/* release all frames in the reorder buffer */
  		release = (tid_agg_rx->head_seq_num + tid_agg_rx->buf_size) %
  			   IEEE80211_SN_MODULO;
  		ieee80211_release_reorder_frames(sta->sdata, tid_agg_rx,
  						 release, &frames);
  		/* update ssn to match received ssn */
  		tid_agg_rx->head_seq_num = ssn;
  	} else {
  		ieee80211_release_reorder_frames(sta->sdata, tid_agg_rx, ssn,
  						 &frames);
  	}
  
  	/* handle the case that received ssn is behind the mac ssn.
  	 * it can be tid_agg_rx->buf_size behind and still be valid */
  	diff = (tid_agg_rx->head_seq_num - ssn) & IEEE80211_SN_MASK;
  	if (diff >= tid_agg_rx->buf_size) {
  		tid_agg_rx->reorder_buf_filtered = 0;
  		goto release;
  	}
  	filtered = filtered >> diff;
  	ssn += diff;
  
  	/* update bitmap */
  	for (i = 0; i < tid_agg_rx->buf_size; i++) {
  		int index = (ssn + i) % tid_agg_rx->buf_size;
  
  		tid_agg_rx->reorder_buf_filtered &= ~BIT_ULL(index);
  		if (filtered & BIT_ULL(i))
  			tid_agg_rx->reorder_buf_filtered |= BIT_ULL(index);
  	}
  
  	/* now process also frames that the filter marking released */
  	ieee80211_sta_reorder_release(sta->sdata, tid_agg_rx, &frames);
  
  release:
  	spin_unlock_bh(&tid_agg_rx->reorder_lock);
  
  	ieee80211_rx_handlers(&rx, &frames);
  
   out:
  	rcu_read_unlock();
  }
  EXPORT_SYMBOL(ieee80211_mark_rx_ba_filtered_frames);
  
  /* main receive path */
  
  static bool ieee80211_accept_frame(struct ieee80211_rx_data *rx)
  {
  	struct ieee80211_sub_if_data *sdata = rx->sdata;
  	struct sk_buff *skb = rx->skb;
  	struct ieee80211_hdr *hdr = (void *)skb->data;
  	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
  	u8 *bssid = ieee80211_get_bssid(hdr, skb->len, sdata->vif.type);
  	bool multicast = is_multicast_ether_addr(hdr->addr1) ||
  			 ieee80211_is_s1g_beacon(hdr->frame_control);
  
  	switch (sdata->vif.type) {
  	case NL80211_IFTYPE_STATION:
  		if (!bssid && !sdata->u.mgd.use_4addr)
  			return false;
  		if (ieee80211_is_robust_mgmt_frame(skb) && !rx->sta)
  			return false;
  		if (multicast)
  			return true;
  		return ether_addr_equal(sdata->vif.addr, hdr->addr1);
  	case NL80211_IFTYPE_ADHOC:
  		if (!bssid)
  			return false;
  		if (ether_addr_equal(sdata->vif.addr, hdr->addr2) ||
  		    ether_addr_equal(sdata->u.ibss.bssid, hdr->addr2) ||
  		    !is_valid_ether_addr(hdr->addr2))
  			return false;
  		if (ieee80211_is_beacon(hdr->frame_control))
  			return true;
  		if (!ieee80211_bssid_match(bssid, sdata->u.ibss.bssid))
  			return false;
  		if (!multicast &&
  		    !ether_addr_equal(sdata->vif.addr, hdr->addr1))
  			return false;
  		if (!rx->sta) {
  			int rate_idx;
  			if (status->encoding != RX_ENC_LEGACY)
  				rate_idx = 0; /* TODO: HT/VHT rates */
  			else
  				rate_idx = status->rate_idx;
  			ieee80211_ibss_rx_no_sta(sdata, bssid, hdr->addr2,
  						 BIT(rate_idx));
  		}
  		return true;
  	case NL80211_IFTYPE_OCB:
  		if (!bssid)
  			return false;
  		if (!ieee80211_is_data_present(hdr->frame_control))
  			return false;
  		if (!is_broadcast_ether_addr(bssid))
  			return false;
  		if (!multicast &&
  		    !ether_addr_equal(sdata->dev->dev_addr, hdr->addr1))
  			return false;
  		if (!rx->sta) {
  			int rate_idx;
  			if (status->encoding != RX_ENC_LEGACY)
  				rate_idx = 0; /* TODO: HT rates */
  			else
  				rate_idx = status->rate_idx;
  			ieee80211_ocb_rx_no_sta(sdata, bssid, hdr->addr2,
  						BIT(rate_idx));
  		}
  		return true;
  	case NL80211_IFTYPE_MESH_POINT:
  		if (ether_addr_equal(sdata->vif.addr, hdr->addr2))
  			return false;
  		if (multicast)
  			return true;
  		return ether_addr_equal(sdata->vif.addr, hdr->addr1);
  	case NL80211_IFTYPE_AP_VLAN:
  	case NL80211_IFTYPE_AP:
  		if (!bssid)
  			return ether_addr_equal(sdata->vif.addr, hdr->addr1);
  
  		if (!ieee80211_bssid_match(bssid, sdata->vif.addr)) {
  			/*
  			 * Accept public action frames even when the
  			 * BSSID doesn't match, this is used for P2P
  			 * and location updates. Note that mac80211
  			 * itself never looks at these frames.
  			 */
  			if (!multicast &&
  			    !ether_addr_equal(sdata->vif.addr, hdr->addr1))
  				return false;
  			if (ieee80211_is_public_action(hdr, skb->len))
  				return true;
  			return ieee80211_is_beacon(hdr->frame_control);
  		}
  
  		if (!ieee80211_has_tods(hdr->frame_control)) {
  			/* ignore data frames to TDLS-peers */
  			if (ieee80211_is_data(hdr->frame_control))
  				return false;
  			/* ignore action frames to TDLS-peers */
  			if (ieee80211_is_action(hdr->frame_control) &&
  			    !is_broadcast_ether_addr(bssid) &&
  			    !ether_addr_equal(bssid, hdr->addr1))
  				return false;
  		}
  
  		/*
  		 * 802.11-2016 Table 9-26 says that for data frames, A1 must be
  		 * the BSSID - we've checked that already but may have accepted
  		 * the wildcard (ff:ff:ff:ff:ff:ff).
  		 *
  		 * It also says:
  		 *	The BSSID of the Data frame is determined as follows:
  		 *	a) If the STA is contained within an AP or is associated
  		 *	   with an AP, the BSSID is the address currently in use
  		 *	   by the STA contained in the AP.
  		 *
  		 * So we should not accept data frames with an address that's
  		 * multicast.
  		 *
  		 * Accepting it also opens a security problem because stations
  		 * could encrypt it with the GTK and inject traffic that way.
  		 */
  		if (ieee80211_is_data(hdr->frame_control) && multicast)
  			return false;
  
  		return true;
  	case NL80211_IFTYPE_WDS:
  		if (bssid || !ieee80211_is_data(hdr->frame_control))
  			return false;
  		return ether_addr_equal(sdata->u.wds.remote_addr, hdr->addr2);
  	case NL80211_IFTYPE_P2P_DEVICE:
  		return ieee80211_is_public_action(hdr, skb->len) ||
  		       ieee80211_is_probe_req(hdr->frame_control) ||
  		       ieee80211_is_probe_resp(hdr->frame_control) ||
  		       ieee80211_is_beacon(hdr->frame_control);
  	case NL80211_IFTYPE_NAN:
  		/* Currently no frames on NAN interface are allowed */
  		return false;
  	default:
  		break;
  	}
  
  	WARN_ON_ONCE(1);
  	return false;
  }
  
  void ieee80211_check_fast_rx(struct sta_info *sta)
  {
  	struct ieee80211_sub_if_data *sdata = sta->sdata;
  	struct ieee80211_local *local = sdata->local;
  	struct ieee80211_key *key;
  	struct ieee80211_fast_rx fastrx = {
  		.dev = sdata->dev,
  		.vif_type = sdata->vif.type,
  		.control_port_protocol = sdata->control_port_protocol,
  	}, *old, *new = NULL;
  	bool assign = false;
  
  	/* use sparse to check that we don't return without updating */
  	__acquire(check_fast_rx);
  
  	BUILD_BUG_ON(sizeof(fastrx.rfc1042_hdr) != sizeof(rfc1042_header));
  	BUILD_BUG_ON(sizeof(fastrx.rfc1042_hdr) != ETH_ALEN);
  	ether_addr_copy(fastrx.rfc1042_hdr, rfc1042_header);
  	ether_addr_copy(fastrx.vif_addr, sdata->vif.addr);
  
  	fastrx.uses_rss = ieee80211_hw_check(&local->hw, USES_RSS);
  
  	/* fast-rx doesn't do reordering */
  	if (ieee80211_hw_check(&local->hw, AMPDU_AGGREGATION) &&
  	    !ieee80211_hw_check(&local->hw, SUPPORTS_REORDERING_BUFFER))
  		goto clear;
  
  	switch (sdata->vif.type) {
  	case NL80211_IFTYPE_STATION:
  		if (sta->sta.tdls) {
  			fastrx.da_offs = offsetof(struct ieee80211_hdr, addr1);
  			fastrx.sa_offs = offsetof(struct ieee80211_hdr, addr2);
  			fastrx.expected_ds_bits = 0;
  		} else {
  			fastrx.da_offs = offsetof(struct ieee80211_hdr, addr1);
  			fastrx.sa_offs = offsetof(struct ieee80211_hdr, addr3);
  			fastrx.expected_ds_bits =
  				cpu_to_le16(IEEE80211_FCTL_FROMDS);
  		}
  
  		if (sdata->u.mgd.use_4addr && !sta->sta.tdls) {
  			fastrx.expected_ds_bits |=
  				cpu_to_le16(IEEE80211_FCTL_TODS);
  			fastrx.da_offs = offsetof(struct ieee80211_hdr, addr3);
  			fastrx.sa_offs = offsetof(struct ieee80211_hdr, addr4);
  		}
  
  		if (!sdata->u.mgd.powersave)
  			break;
  
  		/* software powersave is a huge mess, avoid all of it */
  		if (ieee80211_hw_check(&local->hw, PS_NULLFUNC_STACK))
  			goto clear;
  		if (ieee80211_hw_check(&local->hw, SUPPORTS_PS) &&
  		    !ieee80211_hw_check(&local->hw, SUPPORTS_DYNAMIC_PS))
  			goto clear;
  		break;
  	case NL80211_IFTYPE_AP_VLAN:
  	case NL80211_IFTYPE_AP:
  		/* parallel-rx requires this, at least with calls to
  		 * ieee80211_sta_ps_transition()
  		 */
  		if (!ieee80211_hw_check(&local->hw, AP_LINK_PS))
  			goto clear;
  		fastrx.da_offs = offsetof(struct ieee80211_hdr, addr3);
  		fastrx.sa_offs = offsetof(struct ieee80211_hdr, addr2);
  		fastrx.expected_ds_bits = cpu_to_le16(IEEE80211_FCTL_TODS);
  
  		fastrx.internal_forward =
  			!(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) &&
  			(sdata->vif.type != NL80211_IFTYPE_AP_VLAN ||
  			 !sdata->u.vlan.sta);
  
  		if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
  		    sdata->u.vlan.sta) {
  			fastrx.expected_ds_bits |=
  				cpu_to_le16(IEEE80211_FCTL_FROMDS);
  			fastrx.sa_offs = offsetof(struct ieee80211_hdr, addr4);
  			fastrx.internal_forward = 0;
  		}
  
  		break;
  	default:
  		goto clear;
  	}
  
  	if (!test_sta_flag(sta, WLAN_STA_AUTHORIZED))
  		goto clear;
  
  	rcu_read_lock();
  	key = rcu_dereference(sta->ptk[sta->ptk_idx]);
  	if (!key)
  		key = rcu_dereference(sdata->default_unicast_key);
  	if (key) {
  		switch (key->conf.cipher) {
  		case WLAN_CIPHER_SUITE_TKIP:
  			/* we don't want to deal with MMIC in fast-rx */
  			goto clear_rcu;
  		case WLAN_CIPHER_SUITE_CCMP:
  		case WLAN_CIPHER_SUITE_CCMP_256:
  		case WLAN_CIPHER_SUITE_GCMP:
  		case WLAN_CIPHER_SUITE_GCMP_256:
  			break;
  		default:
  			/* We also don't want to deal with
  			 * WEP or cipher scheme.
  			 */
  			goto clear_rcu;
  		}
  
  		fastrx.key = true;
  		fastrx.icv_len = key->conf.icv_len;
  	}
  
  	assign = true;
   clear_rcu:
  	rcu_read_unlock();
   clear:
  	__release(check_fast_rx);
  
  	if (assign)
  		new = kmemdup(&fastrx, sizeof(fastrx), GFP_KERNEL);
  
  	spin_lock_bh(&sta->lock);
  	old = rcu_dereference_protected(sta->fast_rx, true);
  	rcu_assign_pointer(sta->fast_rx, new);
  	spin_unlock_bh(&sta->lock);
  
  	if (old)
  		kfree_rcu(old, rcu_head);
  }
  
  void ieee80211_clear_fast_rx(struct sta_info *sta)
  {
  	struct ieee80211_fast_rx *old;
  
  	spin_lock_bh(&sta->lock);
  	old = rcu_dereference_protected(sta->fast_rx, true);
  	RCU_INIT_POINTER(sta->fast_rx, NULL);
  	spin_unlock_bh(&sta->lock);
  
  	if (old)
  		kfree_rcu(old, rcu_head);
  }
  
  void __ieee80211_check_fast_rx_iface(struct ieee80211_sub_if_data *sdata)
  {
  	struct ieee80211_local *local = sdata->local;
  	struct sta_info *sta;
  
  	lockdep_assert_held(&local->sta_mtx);
  
  	list_for_each_entry(sta, &local->sta_list, list) {
  		if (sdata != sta->sdata &&
  		    (!sta->sdata->bss || sta->sdata->bss != sdata->bss))
  			continue;
  		ieee80211_check_fast_rx(sta);
  	}
  }
  
  void ieee80211_check_fast_rx_iface(struct ieee80211_sub_if_data *sdata)
  {
  	struct ieee80211_local *local = sdata->local;
  
  	mutex_lock(&local->sta_mtx);
  	__ieee80211_check_fast_rx_iface(sdata);
  	mutex_unlock(&local->sta_mtx);
  }
  
  static bool ieee80211_invoke_fast_rx(struct ieee80211_rx_data *rx,
  				     struct ieee80211_fast_rx *fast_rx)
  {
  	struct sk_buff *skb = rx->skb;
  	struct ieee80211_hdr *hdr = (void *)skb->data;
  	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
  	struct sta_info *sta = rx->sta;
  	int orig_len = skb->len;
  	int hdrlen = ieee80211_hdrlen(hdr->frame_control);
  	int snap_offs = hdrlen;
  	struct {
  		u8 snap[sizeof(rfc1042_header)];
  		__be16 proto;
  	} *payload __aligned(2);
  	struct {
  		u8 da[ETH_ALEN];
  		u8 sa[ETH_ALEN];
  	} addrs __aligned(2);
  	struct ieee80211_sta_rx_stats *stats = &sta->rx_stats;
  
  	if (fast_rx->uses_rss)
  		stats = this_cpu_ptr(sta->pcpu_rx_stats);
  
  	/* for parallel-rx, we need to have DUP_VALIDATED, otherwise we write
  	 * to a common data structure; drivers can implement that per queue
  	 * but we don't have that information in mac80211
  	 */
  	if (!(status->flag & RX_FLAG_DUP_VALIDATED))
  		return false;
  
  #define FAST_RX_CRYPT_FLAGS	(RX_FLAG_PN_VALIDATED | RX_FLAG_DECRYPTED)
  
  	/* If using encryption, we also need to have:
  	 *  - PN_VALIDATED: similar, but the implementation is tricky
  	 *  - DECRYPTED: necessary for PN_VALIDATED
  	 */
  	if (fast_rx->key &&
  	    (status->flag & FAST_RX_CRYPT_FLAGS) != FAST_RX_CRYPT_FLAGS)
  		return false;
  
  	if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
  		return false;
  
  	if (unlikely(ieee80211_is_frag(hdr)))
  		return false;
  
  	/* Since our interface address cannot be multicast, this
  	 * implicitly also rejects multicast frames without the
  	 * explicit check.
  	 *
  	 * We shouldn't get any *data* frames not addressed to us
  	 * (AP mode will accept multicast *management* frames), but
  	 * punting here will make it go through the full checks in
  	 * ieee80211_accept_frame().
  	 */
  	if (!ether_addr_equal(fast_rx->vif_addr, hdr->addr1))
  		return false;
  
  	if ((hdr->frame_control & cpu_to_le16(IEEE80211_FCTL_FROMDS |
  					      IEEE80211_FCTL_TODS)) !=
  	    fast_rx->expected_ds_bits)
  		return false;
  
  	/* assign the key to drop unencrypted frames (later)
  	 * and strip the IV/MIC if necessary
  	 */
  	if (fast_rx->key && !(status->flag & RX_FLAG_IV_STRIPPED)) {
  		/* GCMP header length is the same */
  		snap_offs += IEEE80211_CCMP_HDR_LEN;
  	}
  
  	if (!(status->rx_flags & IEEE80211_RX_AMSDU)) {
  		if (!pskb_may_pull(skb, snap_offs + sizeof(*payload)))
  			goto drop;
  
  		payload = (void *)(skb->data + snap_offs);
  
  		if (!ether_addr_equal(payload->snap, fast_rx->rfc1042_hdr))
  			return false;
  
  		/* Don't handle these here since they require special code.
  		 * Accept AARP and IPX even though they should come with a
  		 * bridge-tunnel header - but if we get them this way then
  		 * there's little point in discarding them.
  		 */
  		if (unlikely(payload->proto == cpu_to_be16(ETH_P_TDLS) ||
  			     payload->proto == fast_rx->control_port_protocol))
  			return false;
  	}
  
  	/* after this point, don't punt to the slowpath! */
  
  	if (rx->key && !(status->flag & RX_FLAG_MIC_STRIPPED) &&
  	    pskb_trim(skb, skb->len - fast_rx->icv_len))
  		goto drop;
  
  	/* statistics part of ieee80211_rx_h_sta_process() */
  	if (!(status->flag & RX_FLAG_NO_SIGNAL_VAL)) {
  		stats->last_signal = status->signal;
  		if (!fast_rx->uses_rss)
  			ewma_signal_add(&sta->rx_stats_avg.signal,
  					-status->signal);
  	}
  
  	if (status->chains) {
  		int i;
  
  		stats->chains = status->chains;
  		for (i = 0; i < ARRAY_SIZE(status->chain_signal); i++) {
  			int signal = status->chain_signal[i];
  
  			if (!(status->chains & BIT(i)))
  				continue;
  
  			stats->chain_signal_last[i] = signal;
  			if (!fast_rx->uses_rss)
  				ewma_signal_add(&sta->rx_stats_avg.chain_signal[i],
  						-signal);
  		}
  	}
  	/* end of statistics */
  
  	if (rx->key && !ieee80211_has_protected(hdr->frame_control))
  		goto drop;
  
  	if (status->rx_flags & IEEE80211_RX_AMSDU) {
  		if (__ieee80211_rx_h_amsdu(rx, snap_offs - hdrlen) !=
  		    RX_QUEUED)
  			goto drop;
  
  		return true;
  	}
  
  	stats->last_rx = jiffies;
  	stats->last_rate = sta_stats_encode_rate(status);
  
  	stats->fragments++;
  	stats->packets++;
  
  	/* do the header conversion - first grab the addresses */
  	ether_addr_copy(addrs.da, skb->data + fast_rx->da_offs);
  	ether_addr_copy(addrs.sa, skb->data + fast_rx->sa_offs);
  	/* remove the SNAP but leave the ethertype */
  	skb_pull(skb, snap_offs + sizeof(rfc1042_header));
  	/* push the addresses in front */
  	memcpy(skb_push(skb, sizeof(addrs)), &addrs, sizeof(addrs));
  
  	skb->dev = fast_rx->dev;
  
  	ieee80211_rx_stats(fast_rx->dev, skb->len);
  
  	/* The seqno index has the same property as needed
  	 * for the rx_msdu field, i.e. it is IEEE80211_NUM_TIDS
  	 * for non-QoS-data frames. Here we know it's a data
  	 * frame, so count MSDUs.
  	 */
  	u64_stats_update_begin(&stats->syncp);
  	stats->msdu[rx->seqno_idx]++;
  	stats->bytes += orig_len;
  	u64_stats_update_end(&stats->syncp);
  
  	if (fast_rx->internal_forward) {
  		struct sk_buff *xmit_skb = NULL;
  		if (is_multicast_ether_addr(addrs.da)) {
  			xmit_skb = skb_copy(skb, GFP_ATOMIC);
  		} else if (!ether_addr_equal(addrs.da, addrs.sa) &&
  			   sta_info_get(rx->sdata, addrs.da)) {
  			xmit_skb = skb;
  			skb = NULL;
  		}
  
  		if (xmit_skb) {
  			/*
  			 * Send to wireless media and increase priority by 256
  			 * to keep the received priority instead of
  			 * reclassifying the frame (see cfg80211_classify8021d).
  			 */
  			xmit_skb->priority += 256;
  			xmit_skb->protocol = htons(ETH_P_802_3);
  			skb_reset_network_header(xmit_skb);
  			skb_reset_mac_header(xmit_skb);
  			dev_queue_xmit(xmit_skb);
  		}
  
  		if (!skb)
  			return true;
  	}
  
  	/* deliver to local stack */
  	skb->protocol = eth_type_trans(skb, fast_rx->dev);
  	memset(skb->cb, 0, sizeof(skb->cb));
  	if (rx->list)
  		list_add_tail(&skb->list, rx->list);
  	else
  		netif_receive_skb(skb);
  
  	return true;
   drop:
  	dev_kfree_skb(skb);
  	stats->dropped++;
  	return true;
  }
  
  /*
   * This function returns whether or not the SKB
   * was destined for RX processing or not, which,
   * if consume is true, is equivalent to whether
   * or not the skb was consumed.
   */
  static bool ieee80211_prepare_and_rx_handle(struct ieee80211_rx_data *rx,
  					    struct sk_buff *skb, bool consume)
  {
  	struct ieee80211_local *local = rx->local;
  	struct ieee80211_sub_if_data *sdata = rx->sdata;
  
  	rx->skb = skb;
  
  	/* See if we can do fast-rx; if we have to copy we already lost,
  	 * so punt in that case. We should never have to deliver a data
  	 * frame to multiple interfaces anyway.
  	 *
  	 * We skip the ieee80211_accept_frame() call and do the necessary
  	 * checking inside ieee80211_invoke_fast_rx().
  	 */
  	if (consume && rx->sta) {
  		struct ieee80211_fast_rx *fast_rx;
  
  		fast_rx = rcu_dereference(rx->sta->fast_rx);
  		if (fast_rx && ieee80211_invoke_fast_rx(rx, fast_rx))
  			return true;
  	}
  
  	if (!ieee80211_accept_frame(rx))
  		return false;
  
  	if (!consume) {
  		skb = skb_copy(skb, GFP_ATOMIC);
  		if (!skb) {
  			if (net_ratelimit())
  				wiphy_debug(local->hw.wiphy,
  					"failed to copy skb for %s\n",
  					sdata->name);
  			return true;
  		}
  
  		rx->skb = skb;
  	}
  
  	ieee80211_invoke_rx_handlers(rx);
  	return true;
  }
  
  /*
   * This is the actual Rx frames handler. as it belongs to Rx path it must
   * be called with rcu_read_lock protection.
   */
  static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
  					 struct ieee80211_sta *pubsta,
  					 struct sk_buff *skb,
  					 struct list_head *list)
  {
  	struct ieee80211_local *local = hw_to_local(hw);
  	struct ieee80211_sub_if_data *sdata;
  	struct ieee80211_hdr *hdr;
  	__le16 fc;
  	struct ieee80211_rx_data rx;
  	struct ieee80211_sub_if_data *prev;
  	struct rhlist_head *tmp;
  	int err = 0;
  
  	fc = ((struct ieee80211_hdr *)skb->data)->frame_control;
  	memset(&rx, 0, sizeof(rx));
  	rx.skb = skb;
  	rx.local = local;
  	rx.list = list;
  
  	if (ieee80211_is_data(fc) || ieee80211_is_mgmt(fc))
  		I802_DEBUG_INC(local->dot11ReceivedFragmentCount);
  
  	if (ieee80211_is_mgmt(fc)) {
  		/* drop frame if too short for header */
  		if (skb->len < ieee80211_hdrlen(fc))
  			err = -ENOBUFS;
  		else
  			err = skb_linearize(skb);
  	} else {
  		err = !pskb_may_pull(skb, ieee80211_hdrlen(fc));
  	}
  
  	if (err) {
  		dev_kfree_skb(skb);
  		return;
  	}
  
  	hdr = (struct ieee80211_hdr *)skb->data;
  	ieee80211_parse_qos(&rx);
  	ieee80211_verify_alignment(&rx);
  
  	if (unlikely(ieee80211_is_probe_resp(hdr->frame_control) ||
  		     ieee80211_is_beacon(hdr->frame_control) ||
  		     ieee80211_is_s1g_beacon(hdr->frame_control)))
  		ieee80211_scan_rx(local, skb);
  
  	if (ieee80211_is_data(fc)) {
  		struct sta_info *sta, *prev_sta;
  
  		if (pubsta) {
  			rx.sta = container_of(pubsta, struct sta_info, sta);
  			rx.sdata = rx.sta->sdata;
  			if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
  				return;
  			goto out;
  		}
  
  		prev_sta = NULL;
  
  		for_each_sta_info(local, hdr->addr2, sta, tmp) {
  			if (!prev_sta) {
  				prev_sta = sta;
  				continue;
  			}
  
  			rx.sta = prev_sta;
  			rx.sdata = prev_sta->sdata;
  			ieee80211_prepare_and_rx_handle(&rx, skb, false);
  
  			prev_sta = sta;
  		}
  
  		if (prev_sta) {
  			rx.sta = prev_sta;
  			rx.sdata = prev_sta->sdata;
  
  			if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
  				return;
  			goto out;
  		}
  	}
  
  	prev = NULL;
  
  	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
  		if (!ieee80211_sdata_running(sdata))
  			continue;
  
  		if (sdata->vif.type == NL80211_IFTYPE_MONITOR ||
  		    sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
  			continue;
  
  		/*
  		 * frame is destined for this interface, but if it's
  		 * not also for the previous one we handle that after
  		 * the loop to avoid copying the SKB once too much
  		 */
  
  		if (!prev) {
  			prev = sdata;
  			continue;
  		}
  
  		rx.sta = sta_info_get_bss(prev, hdr->addr2);
  		rx.sdata = prev;
  		ieee80211_prepare_and_rx_handle(&rx, skb, false);
  
  		prev = sdata;
  	}
  
  	if (prev) {
  		rx.sta = sta_info_get_bss(prev, hdr->addr2);
  		rx.sdata = prev;
  
  		if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
  			return;
  	}
  
   out:
  	dev_kfree_skb(skb);
  }
  
  /*
   * This is the receive path handler. It is called by a low level driver when an
   * 802.11 MPDU is received from the hardware.
   */
  void ieee80211_rx_list(struct ieee80211_hw *hw, struct ieee80211_sta *pubsta,
  		       struct sk_buff *skb, struct list_head *list)
  {
  	struct ieee80211_local *local = hw_to_local(hw);
  	struct ieee80211_rate *rate = NULL;
  	struct ieee80211_supported_band *sband;
  	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
  
  	WARN_ON_ONCE(softirq_count() == 0);
  
  	if (WARN_ON(status->band >= NUM_NL80211_BANDS))
  		goto drop;
  
  	sband = local->hw.wiphy->bands[status->band];
  	if (WARN_ON(!sband))
  		goto drop;
  
  	/*
  	 * If we're suspending, it is possible although not too likely
  	 * that we'd be receiving frames after having already partially
  	 * quiesced the stack. We can't process such frames then since
  	 * that might, for example, cause stations to be added or other
  	 * driver callbacks be invoked.
  	 */
  	if (unlikely(local->quiescing || local->suspended))
  		goto drop;
  
  	/* We might be during a HW reconfig, prevent Rx for the same reason */
  	if (unlikely(local->in_reconfig))
  		goto drop;
  
  	/*
  	 * The same happens when we're not even started,
  	 * but that's worth a warning.
  	 */
  	if (WARN_ON(!local->started))
  		goto drop;
  
  	if (likely(!(status->flag & RX_FLAG_FAILED_PLCP_CRC))) {
  		/*
  		 * Validate the rate, unless a PLCP error means that
  		 * we probably can't have a valid rate here anyway.
  		 */
  
  		switch (status->encoding) {
  		case RX_ENC_HT:
  			/*
  			 * rate_idx is MCS index, which can be [0-76]
  			 * as documented on:
  			 *
  			 * https://wireless.wiki.kernel.org/en/developers/Documentation/ieee80211/802.11n
  			 *
  			 * Anything else would be some sort of driver or
  			 * hardware error. The driver should catch hardware
  			 * errors.
  			 */
  			if (WARN(status->rate_idx > 76,
  				 "Rate marked as an HT rate but passed "
  				 "status->rate_idx is not "
  				 "an MCS index [0-76]: %d (0x%02x)\n",
  				 status->rate_idx,
  				 status->rate_idx))
  				goto drop;
  			break;
  		case RX_ENC_VHT:
  			if (WARN_ONCE(status->rate_idx > 9 ||
  				      !status->nss ||
  				      status->nss > 8,
  				      "Rate marked as a VHT rate but data is invalid: MCS: %d, NSS: %d\n",
  				      status->rate_idx, status->nss))
  				goto drop;
  			break;
  		case RX_ENC_HE:
  			if (WARN_ONCE(status->rate_idx > 11 ||
  				      !status->nss ||
  				      status->nss > 8,
  				      "Rate marked as an HE rate but data is invalid: MCS: %d, NSS: %d\n",
  				      status->rate_idx, status->nss))
  				goto drop;
  			break;
  		default:
  			WARN_ON_ONCE(1);
  			fallthrough;
  		case RX_ENC_LEGACY:
  			if (WARN_ON(status->rate_idx >= sband->n_bitrates))
  				goto drop;
  			rate = &sband->bitrates[status->rate_idx];
  		}
  	}
  
  	status->rx_flags = 0;
  
  	/*
  	 * Frames with failed FCS/PLCP checksum are not returned,
  	 * all other frames are returned without radiotap header
  	 * if it was previously present.
  	 * Also, frames with less than 16 bytes are dropped.
  	 */
  	skb = ieee80211_rx_monitor(local, skb, rate);
  	if (!skb)
  		return;
  
  	ieee80211_tpt_led_trig_rx(local,
  			((struct ieee80211_hdr *)skb->data)->frame_control,
  			skb->len);
  
  	__ieee80211_rx_handle_packet(hw, pubsta, skb, list);
  
  	return;
   drop:
  	kfree_skb(skb);
  }
  EXPORT_SYMBOL(ieee80211_rx_list);
  
  void ieee80211_rx_napi(struct ieee80211_hw *hw, struct ieee80211_sta *pubsta,
  		       struct sk_buff *skb, struct napi_struct *napi)
  {
  	struct sk_buff *tmp;
  	LIST_HEAD(list);
  
  
  	/*
  	 * key references and virtual interfaces are protected using RCU
  	 * and this requires that we are in a read-side RCU section during
  	 * receive processing
  	 */
  	rcu_read_lock();
  	ieee80211_rx_list(hw, pubsta, skb, &list);
  	rcu_read_unlock();
  
  	if (!napi) {
  		netif_receive_skb_list(&list);
  		return;
  	}
  
  	list_for_each_entry_safe(skb, tmp, &list, list) {
  		skb_list_del_init(skb);
  		napi_gro_receive(napi, skb);
  	}
  }
  EXPORT_SYMBOL(ieee80211_rx_napi);
  
  /* This is a version of the rx handler that can be called from hard irq
   * context. Post the skb on the queue and schedule the tasklet */
  void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb)
  {
  	struct ieee80211_local *local = hw_to_local(hw);
  
  	BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
  
  	skb->pkt_type = IEEE80211_RX_MSG;
  	skb_queue_tail(&local->skb_queue, skb);
  	tasklet_schedule(&local->tasklet);
  }
  EXPORT_SYMBOL(ieee80211_rx_irqsafe);
  