HS 2.0: Verify assoc_req_ie buffer size for indication elements

While the buffer is expected to be large enough for all the IEs, it is
better to check for this explicitly when adding the HS 2.0 Indication
element. (CID 68601)

Signed-off-by: Jouni Malinen <j@w1.fi>

wpa_supplicant/sme.c

@@ -361,11 +361,17 @@ static void sme_send_authentication(struct wpa_supplicant *wpa_s,
 		hs20 = wpabuf_alloc(20);
 		if (hs20) {
 			int pps_mo_id = hs20_get_pps_mo_id(wpa_s, ssid);
+			size_t len;
+
 			wpas_hs20_add_indication(hs20, pps_mo_id);
-			os_memcpy(wpa_s->sme.assoc_req_ie +
-				  wpa_s->sme.assoc_req_ie_len,
-				  wpabuf_head(hs20), wpabuf_len(hs20));
-			wpa_s->sme.assoc_req_ie_len += wpabuf_len(hs20);
+			len = sizeof(wpa_s->sme.assoc_req_ie) -
+				wpa_s->sme.assoc_req_ie_len;
+			if (wpabuf_len(hs20) <= len) {
+				os_memcpy(wpa_s->sme.assoc_req_ie +
+					  wpa_s->sme.assoc_req_ie_len,
+					  wpabuf_head(hs20), wpabuf_len(hs20));
+				wpa_s->sme.assoc_req_ie_len += wpabuf_len(hs20);
+			}
 			wpabuf_free(hs20);
 		}
 	}

wpa_supplicant/wpa_supplicant.c

@@ -1656,10 +1656,15 @@ static void wpas_start_assoc_cb(struct wpa_radio_work *work, int deinit)
 		hs20 = wpabuf_alloc(20);
 		if (hs20) {
 			int pps_mo_id = hs20_get_pps_mo_id(wpa_s, ssid);
+			size_t len;
+
 			wpas_hs20_add_indication(hs20, pps_mo_id);
-			os_memcpy(wpa_ie + wpa_ie_len, wpabuf_head(hs20),
-				  wpabuf_len(hs20));
-			wpa_ie_len += wpabuf_len(hs20);
+			len = sizeof(wpa_ie) - wpa_ie_len;
+			if (wpabuf_len(hs20) <= len) {
+				os_memcpy(wpa_ie + wpa_ie_len,
+					  wpabuf_head(hs20), wpabuf_len(hs20));
+				wpa_ie_len += wpabuf_len(hs20);
+			}
 			wpabuf_free(hs20);
 		}
 	}