Make GTK length validation easier to analyze

Bounds checking for gd->gtk_len in wpa_supplicant_check_group_cipher()
was apparently too complex for some static analyzers. Use a local
variable and a more explicit validation step to avoid false report.
(CID 62864)

Signed-off-by: Jouni Malinen <j@w1.fi>
This commit is contained in:
Jouni Malinen 2014-12-05 23:05:11 +02:00
parent 369d07afc1
commit c397eff828

View File

@ -1276,8 +1276,9 @@ static int wpa_supplicant_process_1_of_2_wpa(struct wpa_sm *sm,
u16 ver, struct wpa_gtk_data *gd)
{
size_t maxkeylen;
u16 gtk_len;
gd->gtk_len = WPA_GET_BE16(key->key_length);
gtk_len = WPA_GET_BE16(key->key_length);
maxkeylen = key_data_len;
if (ver == WPA_KEY_INFO_TYPE_HMAC_SHA1_AES) {
if (maxkeylen < 8) {
@ -1289,11 +1290,13 @@ static int wpa_supplicant_process_1_of_2_wpa(struct wpa_sm *sm,
maxkeylen -= 8;
}
if (wpa_supplicant_check_group_cipher(sm, sm->group_cipher,
gd->gtk_len, maxkeylen,
if (gtk_len > maxkeylen ||
wpa_supplicant_check_group_cipher(sm, sm->group_cipher,
gtk_len, maxkeylen,
&gd->key_rsc_len, &gd->alg))
return -1;
gd->gtk_len = gtk_len;
gd->keyidx = (key_info & WPA_KEY_INFO_KEY_INDEX_MASK) >>
WPA_KEY_INFO_KEY_INDEX_SHIFT;
if (ver == WPA_KEY_INFO_TYPE_HMAC_MD5_RC4) {