mac80211: check power constraint IE size when parsing

The power constraint IE is always a single byte
so check the size when parsing instead of later.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This commit is contained in:
Johannes Berg 2012-09-05 13:07:00 +02:00
parent f8fffc7e51
commit 761a48d260
3 changed files with 6 additions and 10 deletions

View file

@ -1165,7 +1165,6 @@ struct ieee802_11_elems {
u8 prep_len;
u8 perr_len;
u8 country_elem_len;
u8 pwr_constr_elem_len;
u8 quiet_elem_len;
u8 num_of_quiet_elem; /* can be more the one */
u8 timeout_int_len;

View file

@ -821,18 +821,13 @@ void ieee80211_sta_process_chanswitch(struct ieee80211_sub_if_data *sdata,
}
static void ieee80211_handle_pwr_constr(struct ieee80211_sub_if_data *sdata,
u16 capab_info, u8 *pwr_constr_elem,
u8 pwr_constr_elem_len)
u16 capab_info, u8 *pwr_constr_elem)
{
struct ieee80211_conf *conf = &sdata->local->hw.conf;
if (!(capab_info & WLAN_CAPABILITY_SPECTRUM_MGMT))
return;
/* Power constraint IE length should be 1 octet */
if (pwr_constr_elem_len != 1)
return;
if ((*pwr_constr_elem <= conf->channel->max_reg_power) &&
(*pwr_constr_elem != sdata->local->power_constr_level)) {
sdata->local->power_constr_level = *pwr_constr_elem;
@ -2552,8 +2547,7 @@ static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata,
if (elems.pwr_constr_elem)
ieee80211_handle_pwr_constr(sdata,
le16_to_cpu(mgmt->u.probe_resp.capab_info),
elems.pwr_constr_elem,
elems.pwr_constr_elem_len);
elems.pwr_constr_elem);
}
ieee80211_bss_info_change_notify(sdata, changed);

View file

@ -792,8 +792,11 @@ u32 ieee802_11_parse_elems_crc(u8 *start, size_t len,
elems->country_elem_len = elen;
break;
case WLAN_EID_PWR_CONSTRAINT:
if (elen != 1) {
elem_parse_failed = true;
break;
}
elems->pwr_constr_elem = pos;
elems->pwr_constr_elem_len = elen;
break;
case WLAN_EID_TIMEOUT_INTERVAL:
elems->timeout_int = pos;