diff --git a/library/psa_crypto_mac.c b/library/psa_crypto_mac.c
index 0189cde..d8e2293 100644
--- a/library/psa_crypto_mac.c
+++ b/library/psa_crypto_mac.c
@@ -243,7 +243,7 @@
     mbedtls_psa_mac_operation_t *operation,
     psa_algorithm_t alg )
 {
-    psa_status_t status = PSA_ERROR_NOT_SUPPORTED;
+    psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
 
     operation->alg = PSA_ALG_FULL_LENGTH_MAC( alg );
     operation->key_set = 0;
@@ -268,8 +268,7 @@
     else
 #endif /* BUILTIN_ALG_HMAC */
     {
-        if( ! PSA_ALG_IS_MAC( alg ) )
-            status = PSA_ERROR_INVALID_ARGUMENT;
+        status = PSA_ERROR_NOT_SUPPORTED;
     }
 
     if( status != PSA_SUCCESS )