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@xxxxxxxxxxxxxxxx>
---
net/mac80211/ieee80211_i.h | 6 ++----
net/mac80211/mlme.c | 3 ---
net/mac80211/util.c | 8 ++++----
3 files changed, 6 insertions(+), 11 deletions(-)
--- everything.orig/net/mac80211/ieee80211_i.h 2008-10-07 16:52:04.000000000 +0200
+++ everything/net/mac80211/ieee80211_i.h 2008-10-07 16:53:04.000000000 +0200
@@ -816,8 +816,8 @@ struct ieee802_11_elems {
u8 *ext_supp_rates;
u8 *wmm_info;
u8 *wmm_param;
- u8 *ht_cap_elem;
- u8 *ht_info_elem;
+ struct ieee80211_ht_cap *ht_cap_elem;
+ struct ieee80211_ht_addt_info *ht_info_elem;
u8 *mesh_config;
u8 *mesh_id;
u8 *peer_link;
@@ -844,8 +844,6 @@ struct ieee802_11_elems {
u8 ext_supp_rates_len;
u8 wmm_info_len;
u8 wmm_param_len;
- u8 ht_cap_elem_len;
- u8 ht_info_elem_len;
u8 mesh_config_len;
u8 mesh_id_len;
u8 peer_link_len;
--- everything.orig/net/mac80211/mlme.c 2008-10-07 16:52:45.000000000 +0200
+++ everything/net/mac80211/mlme.c 2008-10-07 16:54:01.000000000 +0200
@@ -1347,10 +1347,8 @@ static void ieee80211_rx_mgmt_assoc_resp
(ifsta->flags & IEEE80211_STA_WMM_ENABLED)) {
struct ieee80211_ht_bss_info bss_info;
ieee80211_ht_cap_ie_to_ht_info(
- (struct ieee80211_ht_cap *)
elems.ht_cap_elem, &sta->sta.ht_info);
ieee80211_ht_addt_info_ie_to_ht_bss_info(
- (struct ieee80211_ht_addt_info *)
elems.ht_info_elem, &bss_info);
ieee80211_handle_ht(local, 1, &sta->sta.ht_info, &bss_info);
}
@@ -1713,7 +1711,6 @@ static void ieee80211_rx_mgmt_beacon(str
struct ieee80211_ht_bss_info bss_info;
ieee80211_ht_addt_info_ie_to_ht_bss_info(
- (struct ieee80211_ht_addt_info *)
elems.ht_info_elem, &bss_info);
changed |= ieee80211_handle_ht(local, 1, &conf->ht_conf,
&bss_info);
--- everything.orig/net/mac80211/util.c 2008-10-07 16:51:56.000000000 +0200
+++ everything/net/mac80211/util.c 2008-10-07 16:54:57.000000000 +0200
@@ -529,12 +529,12 @@ void ieee802_11_parse_elems(u8 *start, s
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;
--
To unsubscribe from this list: send the line "unsubscribe linux-wireless" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
