Commit c17fe043 authored by Sara Sharon's avatar Sara Sharon Committed by Johannes Berg
Browse files

cfg80211: fix the IE inheritance of extension IEs 



Extension IEs have ID 255 followed by extension ID. Current
code is buggy in handling it in two ways:
1. When checking if IE is in the frame, it uses just the ID, which
   for extension elements is too broad.
2. It uses 0xFF to mark copied IEs, which will result in not copying
   extension IEs from the subelement.

Fix both issue.

Signed-off-by: default avatarSara Sharon <sara.sharon@intel.com>
Signed-off-by: default avatarJohannes Berg <johannes.berg@intel.com>
parent caf56338

net/wireless/scan.c

+13 −7
Original line number Diff line number Diff line
@@ -216,7 +216,13 @@ static size_t cfg80211_gen_new_ie(const u8 *ie, size_t ielen, 
			continue;

		}



		tmp = (u8 *)cfg80211_find_ie(tmp_old[0], sub_copy, subie_len);

		if (tmp_old[0] == WLAN_EID_EXTENSION)

			tmp = (u8 *)cfg80211_find_ext_ie(tmp_old[2], sub_copy,

							 subie_len);

		else

			tmp = (u8 *)cfg80211_find_ie(tmp_old[0], sub_copy,

						     subie_len);



		if (!tmp) {

			/* ie in old ie but not in subelement */

			if (tmp_old[0] != WLAN_EID_MULTIPLE_BSSID) {
@@ -226,8 +232,9 @@ static size_t cfg80211_gen_new_ie(const u8 *ie, size_t ielen, 
		} else {

			/* ie in transmitting ie also in subelement,

			 * copy from subelement and flag the ie in subelement

			 * as copied (by setting eid field to 0xff). For

			 * vendor ie, compare OUI + type + subType to

			 * as copied (by setting eid field to WLAN_EID_SSID,

			 * which is skipped anyway).

			 * For vendor ie, compare OUI + type + subType to

			 * determine if they are the same ie.

			 */

			if (tmp_old[0] == WLAN_EID_VENDOR_SPECIFIC) {
@@ -237,7 +244,7 @@ static size_t cfg80211_gen_new_ie(const u8 *ie, size_t ielen, 
					 */

					memcpy(pos, tmp, tmp[1] + 2);

					pos += tmp[1] + 2;

					tmp[0] = 0xff;

					tmp[0] = WLAN_EID_SSID;

				} else {

					memcpy(pos, tmp_old, tmp_old[1] + 2);

					pos += tmp_old[1] + 2;
@@ -246,7 +253,7 @@ static size_t cfg80211_gen_new_ie(const u8 *ie, size_t ielen, 
				/* copy ie from subelement into new ie */

				memcpy(pos, tmp, tmp[1] + 2);

				pos += tmp[1] + 2;

				tmp[0] = 0xff;

				tmp[0] = WLAN_EID_SSID;

			}

		}
@@ -263,8 +270,7 @@ static size_t cfg80211_gen_new_ie(const u8 *ie, size_t ielen, 
	while (tmp_new + tmp_new[1] + 2 - sub_copy <= subie_len) {

		if (!(tmp_new[0] == WLAN_EID_NON_TX_BSSID_CAP ||

		      tmp_new[0] == WLAN_EID_SSID ||

		      tmp_new[0] == WLAN_EID_MULTI_BSSID_IDX ||

		      tmp_new[0] == 0xff)) {

		      tmp_new[0] == WLAN_EID_MULTI_BSSID_IDX)) {

			memcpy(pos, tmp_new, tmp_new[1] + 2);

			pos += tmp_new[1] + 2;

		}

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