Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 569d099d authored by Johannes Berg's avatar Johannes Berg Committed by Treehugger Robot
Browse files

UPSTREAM: wifi: cfg80211: ensure length byte is present before access 



commit 567e14e39e8f8c6997a1378bc3be615afca86063 upstream.

When iterating the elements here, ensure the length byte is
present before checking it to see if the entire element will
fit into the buffer.

Longer term, we should rewrite this code using the type-safe
element iteration macros that check all of this.

Bug: 254180332
Fixes: 0b8fb823 ("cfg80211: Parsing of Multiple BSSID information in scanning")
Reported-by: default avatarSoenke Huster <shuster@seemoo.tu-darmstadt.de>
Signed-off-by: default avatarJohannes Berg <johannes.berg@intel.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: default avatarLee Jones <joneslee@google.com>
Change-Id: I2ff6215eabd24d0fbb57a9467cdd548523ffbd9b
parent 916a29b4

net/wireless/scan.c

+4 −2
Original line number Diff line number Diff line
@@ -259,7 +259,8 @@ static size_t cfg80211_gen_new_ie(const u8 *ie, size_t ielen, 
	tmp_old = cfg80211_find_ie(WLAN_EID_SSID, ie, ielen);

	tmp_old = (tmp_old) ? tmp_old + tmp_old[1] + 2 : ie;



	while (tmp_old + tmp_old[1] + 2 - ie <= ielen) {

	while (tmp_old + 2 - ie <= ielen &&

	       tmp_old + tmp_old[1] + 2 - ie <= ielen) {

		if (tmp_old[0] == 0) {

			tmp_old++;

			continue;
@@ -319,7 +320,8 @@ static size_t cfg80211_gen_new_ie(const u8 *ie, size_t ielen, 
	 * copied to new ie, skip ssid, capability, bssid-index ie

	 */

	tmp_new = sub_copy;

	while (tmp_new + tmp_new[1] + 2 - sub_copy <= subie_len) {

	while (tmp_new + 2 - sub_copy <= subie_len &&

	       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)) {

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