mwifiex: Don't abort on small, spec-compliant vendor IEs

Per the 802.11 specification, vendor IEs are (at minimum) only required
to contain an OUI. A type field is also included in ieee80211.h (struct
ieee80211_vendor_ie) but doesn't appear in the specification. The
remaining fields (subtype, version) are a convention used in WMM
headers.

Thus, we should not reject vendor-specific IEs that have only the
minimum length (3 bytes) -- we should skip over them (since we only want
to match longer IEs, that match either WMM or WPA formats). We can
reject elements that don't have the minimum-required 3 byte OUI.

While we're at it, move the non-standard subtype and version fields into
the WMM structs, to avoid this confusion in the future about generic
"vendor header" attributes.

Fixes: 685c9b7750 ("mwifiex: Abort at too short BSS descriptor element")
Cc: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Brian Norris <briannorris@chromium.org>
Reviewed-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
This commit is contained in:
Brian Norris 2019-06-14 17:13:20 -07:00 committed by Kalle Valo
parent 608fd72143
commit 63d7ef3610
4 changed files with 23 additions and 13 deletions

View File

@ -1759,9 +1759,10 @@ struct mwifiex_ie_types_wmm_queue_status {
struct ieee_types_vendor_header {
u8 element_id;
u8 len;
u8 oui[4]; /* 0~2: oui, 3: oui_type */
u8 oui_subtype;
u8 version;
struct {
u8 oui[3];
u8 oui_type;
} __packed oui;
} __packed;
struct ieee_types_wmm_parameter {
@ -1775,6 +1776,9 @@ struct ieee_types_wmm_parameter {
* Version [1]
*/
struct ieee_types_vendor_header vend_hdr;
u8 oui_subtype;
u8 version;
u8 qos_info_bitmap;
u8 reserved;
struct ieee_types_wmm_ac_parameters ac_params[IEEE80211_NUM_ACS];
@ -1792,6 +1796,8 @@ struct ieee_types_wmm_info {
* Version [1]
*/
struct ieee_types_vendor_header vend_hdr;
u8 oui_subtype;
u8 version;
u8 qos_info_bitmap;
} __packed;

View File

@ -1361,21 +1361,25 @@ int mwifiex_update_bss_desc_with_ie(struct mwifiex_adapter *adapter,
break;
case WLAN_EID_VENDOR_SPECIFIC:
if (element_len + 2 < sizeof(vendor_ie->vend_hdr))
return -EINVAL;
vendor_ie = (struct ieee_types_vendor_specific *)
current_ptr;
if (!memcmp
(vendor_ie->vend_hdr.oui, wpa_oui,
sizeof(wpa_oui))) {
/* 802.11 requires at least 3-byte OUI. */
if (element_len < sizeof(vendor_ie->vend_hdr.oui.oui))
return -EINVAL;
/* Not long enough for a match? Skip it. */
if (element_len < sizeof(wpa_oui))
break;
if (!memcmp(&vendor_ie->vend_hdr.oui, wpa_oui,
sizeof(wpa_oui))) {
bss_entry->bcn_wpa_ie =
(struct ieee_types_vendor_specific *)
current_ptr;
bss_entry->wpa_offset = (u16)
(current_ptr - bss_entry->beacon_buf);
} else if (!memcmp(vendor_ie->vend_hdr.oui, wmm_oui,
} else if (!memcmp(&vendor_ie->vend_hdr.oui, wmm_oui,
sizeof(wmm_oui))) {
if (total_ie_len ==
sizeof(struct ieee_types_wmm_parameter) ||

View File

@ -1351,7 +1351,7 @@ mwifiex_set_gen_ie_helper(struct mwifiex_private *priv, u8 *ie_data_ptr,
/* Test to see if it is a WPA IE, if not, then
* it is a gen IE
*/
if (!memcmp(pvendor_ie->oui, wpa_oui,
if (!memcmp(&pvendor_ie->oui, wpa_oui,
sizeof(wpa_oui))) {
/* IE is a WPA/WPA2 IE so call set_wpa function
*/
@ -1361,7 +1361,7 @@ mwifiex_set_gen_ie_helper(struct mwifiex_private *priv, u8 *ie_data_ptr,
goto next_ie;
}
if (!memcmp(pvendor_ie->oui, wps_oui,
if (!memcmp(&pvendor_ie->oui, wps_oui,
sizeof(wps_oui))) {
/* Test to see if it is a WPS IE,
* if so, enable wps session flag

View File

@ -240,7 +240,7 @@ mwifiex_wmm_setup_queue_priorities(struct mwifiex_private *priv,
mwifiex_dbg(priv->adapter, INFO,
"info: WMM Parameter IE: version=%d,\t"
"qos_info Parameter Set Count=%d, Reserved=%#x\n",
wmm_ie->vend_hdr.version, wmm_ie->qos_info_bitmap &
wmm_ie->version, wmm_ie->qos_info_bitmap &
IEEE80211_WMM_IE_AP_QOSINFO_PARAM_SET_CNT_MASK,
wmm_ie->reserved);