From: Johannes Berg johannes.berg@intel.com
commit 768c0b19b50665e337c96858aa2b7928d6dcf756 upstream.
Before attempting to parse an extended element, verify that the extended element ID is present.
Fixes: 41cbb0f5a295 ("mac80211: add support for HE") Reported-by: syzbot+59bdff68edce82e393b6@syzkaller.appspotmail.com Link: https://lore.kernel.org/r/20211211201023.f30a1b128c07.I5cacc176da94ba316877c... Cc: stable@vger.kernel.org Signed-off-by: Johannes Berg johannes.berg@intel.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/mac80211/util.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)
--- a/net/mac80211/util.c +++ b/net/mac80211/util.c @@ -950,7 +950,12 @@ static void ieee80211_parse_extension_el 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: