Commit dc92e54c authored by Benjamin Berg's avatar Benjamin Berg Committed by Johannes Berg
Browse files

wifi: cfg80211: use structs for TBTT information access 



Make the data access a bit nicer overall by using structs. There is a
small change here to also accept a TBTT information length of eight
bytes as we do not require the 20 MHz PSD information.

This also fixes a bug reading the short SSID on big endian machines.

Signed-off-by: default avatarBenjamin Berg <benjamin.berg@intel.com>
Signed-off-by: default avatarGregory Greenman <gregory.greenman@intel.com>
Link: https://lore.kernel.org/r/20230618214436.4c3f8901c1bc.Ic3e94fd6e1bccff7948a252ad3bb87e322690a17@changeid


Signed-off-by: default avatarJohannes Berg <johannes.berg@intel.com>
parent 50181fe4

include/linux/ieee80211.h

+0 −3
Original line number Diff line number Diff line
@@ -4483,9 +4483,6 @@ static inline bool for_each_element_completed(const struct element *element, 
#define IEEE80211_AP_INFO_TBTT_HDR_COUNT			0xF0

#define IEEE80211_TBTT_INFO_TYPE_TBTT				0

#define IEEE80211_TBTT_INFO_TYPE_MLD				1

#define IEEE80211_TBTT_INFO_OFFSET_BSSID_BSS_PARAM		9

#define IEEE80211_TBTT_INFO_OFFSET_BSSID_SSSID_BSS_PARAM	13

#define IEEE80211_TBTT_INFO_OFFSET_BSSID_SSSID_BSS_PARAM_MLD_PARAM	16



#define IEEE80211_RNR_TBTT_PARAMS_OCT_RECOMMENDED		0x01

#define IEEE80211_RNR_TBTT_PARAMS_SAME_SSID			0x02

net/wireless/scan.c

+33 −28
Original line number Diff line number Diff line
@@ -574,39 +574,41 @@ static void cfg80211_free_coloc_ap_list(struct list_head *coloc_ap_list) 
static int cfg80211_parse_ap_info(struct cfg80211_colocated_ap *entry,

				  const u8 *pos, u8 length,

				  const struct element *ssid_elem,

				  int s_ssid_tmp)

				  u32 s_ssid_tmp)

{

	/* skip the TBTT offset */

	pos++;

	u8 bss_params;



	/* ignore entries with invalid BSSID */

	if (!is_valid_ether_addr(pos))

		return -EINVAL;

	/* The length is already verified by the caller to contain bss_params */

	if (length > sizeof(struct ieee80211_tbtt_info_7_8_9)) {

		struct ieee80211_tbtt_info_ge_11 *tbtt_info = (void *)pos;



	memcpy(entry->bssid, pos, ETH_ALEN);

	pos += ETH_ALEN;



	if (length >= IEEE80211_TBTT_INFO_OFFSET_BSSID_SSSID_BSS_PARAM) {

		memcpy(&entry->short_ssid, pos,

		       sizeof(entry->short_ssid));

		memcpy(entry->bssid, tbtt_info->bssid, ETH_ALEN);

		entry->short_ssid = le32_to_cpu(tbtt_info->short_ssid);

		entry->short_ssid_valid = true;

		pos += 4;



		bss_params = tbtt_info->bss_params;

	} else {

		struct ieee80211_tbtt_info_7_8_9 *tbtt_info = (void *)pos;



		memcpy(entry->bssid, tbtt_info->bssid, ETH_ALEN);



		bss_params = tbtt_info->bss_params;

	}



	/* ignore entries with invalid BSSID */

	if (!is_valid_ether_addr(entry->bssid))

		return -EINVAL;



	/* skip non colocated APs */

	if (!cfg80211_parse_bss_param(*pos, entry))

	if (!cfg80211_parse_bss_param(bss_params, entry))

		return -EINVAL;

	pos++;



	if (length == IEEE80211_TBTT_INFO_OFFSET_BSSID_BSS_PARAM) {

		/*

		 * no information about the short ssid. Consider the entry valid

	/* no information about the short ssid. Consider the entry valid

	 * for now. It would later be dropped in case there are explicit

	 * SSIDs that need to be matched

	 */

		if (!entry->same_ssid)

	if (!entry->same_ssid && !entry->short_ssid_valid)

		return 0;

	}



	if (entry->same_ssid) {

		entry->short_ssid = s_ssid_tmp;
@@ -617,10 +619,10 @@ static int cfg80211_parse_ap_info(struct cfg80211_colocated_ap *entry, 
		 * cfg80211_parse_colocated_ap(), before calling this

		 * function.

		 */

		memcpy(&entry->ssid, &ssid_elem->data,

		       ssid_elem->datalen);

		memcpy(&entry->ssid, &ssid_elem->data, ssid_elem->datalen);

		entry->ssid_len = ssid_elem->datalen;

	}



	return 0;

}
@@ -682,8 +684,11 @@ static int cfg80211_parse_colocated_ap(const struct cfg80211_bss_ies *ies, 
		 * next AP info

		 */

		if (band != NL80211_BAND_6GHZ ||

		    (length != IEEE80211_TBTT_INFO_OFFSET_BSSID_BSS_PARAM &&

		     length < IEEE80211_TBTT_INFO_OFFSET_BSSID_SSSID_BSS_PARAM)) {

		    !(length == offsetofend(struct ieee80211_tbtt_info_7_8_9,

					    bss_params) ||

		      length == sizeof(struct ieee80211_tbtt_info_7_8_9) ||

		      length >= offsetofend(struct ieee80211_tbtt_info_ge_11,

					    bss_params))) {

			pos += count * length;

			continue;

		}