Commit c4863491 authored by Johannes Berg's avatar Johannes Berg Committed by Jialin Zhang
Browse files

wifi: cfg80211: ensure length byte is present before access 

stable inclusion
from stable-v5.10.148
commit 6144c97f96f5cc3ede984b224fdf8dde658cfcad
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I6D0WL

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=6144c97f96f5cc3ede984b224fdf8dde658cfcad



--------------------------------

commit 567e14e3 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.

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 avatarJialin Zhang <zhangjialin11@huawei.com>
Reviewed-by: default avatarZheng Zengkai <zhengzengkai@huawei.com>
parent e12ee596

net/wireless/scan.c

+4 −2
Original line number Diff line number Diff line
@@ -298,7 +298,8 @@ 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;
@@ -358,7 +359,8 @@ 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);