mac80211: validate extended element ID is present

Before attempting to parse an extended element, verify that
the extended element ID is present.

Fixes: 41cbb0f5a2 ("mac80211: add support for HE")
Reported-by: syzbot+59bdff68edce82e393b6@syzkaller.appspotmail.com
Link: https://lore.kernel.org/r/20211211201023.f30a1b128c07.I5cacc176da94ba316877c6e10fe3ceec8b4dbd7d@changeid
Cc: stable@vger.kernel.org
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This commit is contained in:
Johannes Berg 2021-12-11 20:10:24 +01:00
parent e08ebd6d7b
commit 768c0b19b5

View File

@ -943,7 +943,12 @@ static void ieee80211_parse_extension_element(u32 *crc,
struct ieee802_11_elems *elems)
{
const void *data = elem->data + 1;
u8 len = elem->datalen - 1;
u8 len;
if (!elem->datalen)
return;
len = elem->datalen - 1;
switch (elem->data[0]) {
case WLAN_EID_EXT_HE_MU_EDCA: