Fix the vendor defined message length check in requester.

Signed-off-by: Jiewen Yao <[email protected]>

library/spdm_requester_lib/libspdm_req_vendor_request.c

@@ -1,5 +1,5 @@
 /**
- *  Copyright 2023 DMTF. All rights reserved.
+ *  Copyright 2023-2024 DMTF. All rights reserved.
  *  License: BSD 3-Clause License. For full text see link: https://github.com/DMTF/libspdm/blob/main/LICENSE.md
  **/
 
@@ -147,10 +147,7 @@ libspdm_return_t libspdm_try_vendor_send_request_receive_response(
     }
 
     /* -=[Validate Response Phase]=- */
-    /* check response buffer size at least spdm response default header plus
-     * number of bytes required by vendor id and 2 bytes for response payload size */
-    if (spdm_response_size < sizeof(spdm_vendor_defined_response_msg_t) +
-        spdm_response->vendor_id_len + sizeof(uint16_t)) {
+    if (spdm_response_size < sizeof(spdm_message_header_t)) {
         status = LIBSPDM_STATUS_INVALID_MSG_SIZE;
         goto done;
     }
@@ -172,6 +169,18 @@ libspdm_return_t libspdm_try_vendor_send_request_receive_response(
         goto done;
     }
 
+    if (spdm_response_size < sizeof(spdm_vendor_defined_response_msg_t)) {
+        status = LIBSPDM_STATUS_INVALID_MSG_SIZE;
+        goto done;
+    }
+    /* check response buffer size at least spdm response default header plus
+     * number of bytes required by vendor id and 2 bytes for response payload size */
+    if (spdm_response_size < sizeof(spdm_vendor_defined_response_msg_t) +
+        spdm_response->vendor_id_len + sizeof(uint16_t)) {
+        status = LIBSPDM_STATUS_INVALID_MSG_SIZE;
+        goto done;
+    }
+
     *resp_standard_id = spdm_response->standard_id;
     if (*resp_vendor_id_len < spdm_response->vendor_id_len) {
         status = LIBSPDM_STATUS_INVALID_MSG_SIZE;