1 files changed, 3 insertions, 1 deletions
diff --git a/pkcs11.c b/pkcs11.c
index 914607e..88ad883 100644
--- a/pkcs11.c
+++ b/pkcs11.c
@@ -2405,10 +2405,12 @@ static CK_RV sign_ecdsa(p11_session_t *session,
   }
 
   if (pSignature != NULL && !hal_check(hal_ecdsa_sign(key, pData, ulDataLen,
-                                                      pSignature, pulSignatureLen, *pulSignatureLen,
+                                                      pSignature, &signature_len, *pulSignatureLen,
                                                       HAL_ECDSA_SIGNATURE_FORMAT_PKCS11)))
     lose(CKR_FUNCTION_FAILED);
 
+  assert(signature_len == *pulSignatureLen);
+
   rv = CKR_OK;                  /* Fall through */
 
  fail: