mac80211: fix HT information element parsing
There's no checking that the HT IEs are of the right length
which can be used by an attacker to cause an out-of-bounds
access by sending a too short HT information/capability IE.
Fix it by simply pretending those IEs didn't exist when too
short.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/net/mac80211/util.c b/net/mac80211/util.c
index f32561e..cee4884 100644
--- a/net/mac80211/util.c
+++ b/net/mac80211/util.c
@@ -529,12 +529,12 @@
elems->ext_supp_rates_len = elen;
break;
case WLAN_EID_HT_CAPABILITY:
- elems->ht_cap_elem = pos;
- elems->ht_cap_elem_len = elen;
+ if (elen >= sizeof(struct ieee80211_ht_cap))
+ elems->ht_cap_elem = (void *)pos;
break;
case WLAN_EID_HT_EXTRA_INFO:
- elems->ht_info_elem = pos;
- elems->ht_info_elem_len = elen;
+ if (elen >= sizeof(struct ieee80211_ht_addt_info))
+ elems->ht_info_elem = (void *)pos;
break;
case WLAN_EID_MESH_ID:
elems->mesh_id = pos;