diff --git a/library/psa_crypto.c b/library/psa_crypto.c
index 37389f8..b9369fe 100644
--- a/library/psa_crypto.c
+++ b/library/psa_crypto.c
@@ -3558,6 +3558,12 @@
 {
     psa_status_t status;
     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
+
+    if( operation->alg == 0 )
+    {
+        return( PSA_ERROR_BAD_STATE );
+    }
+
     if( operation->iv_set || ! operation->iv_required )
     {
         return( PSA_ERROR_BAD_STATE );
@@ -3602,6 +3608,12 @@
 {
     psa_status_t status;
     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
+
+    if( operation->alg == 0 )
+    {
+        return( PSA_ERROR_BAD_STATE );
+    }
+
     if( operation->iv_set || ! operation->iv_required )
     {
         return( PSA_ERROR_BAD_STATE );
diff --git a/library/psa_crypto_driver_wrappers.c b/library/psa_crypto_driver_wrappers.c
index 6c94472..9fbc610 100644
--- a/library/psa_crypto_driver_wrappers.c
+++ b/library/psa_crypto_driver_wrappers.c
@@ -779,7 +779,7 @@
 #endif /* PSA_CRYPTO_DRIVER_TEST */
         default:
             /* Key is declared with a lifetime not known to us */
-            return( PSA_ERROR_NOT_SUPPORTED );
+            return( PSA_ERROR_INVALID_ARGUMENT );
     }
 #else /* PSA_CRYPTO_DRIVER_PRESENT */
     (void)slot;
@@ -860,7 +860,7 @@
 #endif /* PSA_CRYPTO_DRIVER_TEST */
         default:
             /* Key is declared with a lifetime not known to us */
-            return( PSA_ERROR_NOT_SUPPORTED );
+            return( PSA_ERROR_INVALID_ARGUMENT );
     }
 #else /* PSA_CRYPTO_DRIVER_PRESENT */
     (void)slot;
@@ -896,7 +896,7 @@
 #endif /* PSA_CRYPTO_DRIVER_TEST */
         default:
             /* Key is attached to a driver not known to us */
-            return( PSA_ERROR_BAD_STATE );
+            return( PSA_ERROR_INVALID_ARGUMENT );
     }
 #else /* PSA_CRYPTO_DRIVER_PRESENT */
     (void) operation;
@@ -930,7 +930,7 @@
 #endif /* PSA_CRYPTO_DRIVER_TEST */
         default:
             /* Key is attached to a driver not known to us */
-            return( PSA_ERROR_BAD_STATE );
+            return( PSA_ERROR_INVALID_ARGUMENT );
     }
 #else /* PSA_CRYPTO_DRIVER_PRESENT */
     (void) operation;
@@ -972,7 +972,7 @@
 #endif /* PSA_CRYPTO_DRIVER_TEST */
         default:
             /* Key is attached to a driver not known to us */
-            return( PSA_ERROR_BAD_STATE );
+            return( PSA_ERROR_INVALID_ARGUMENT );
     }
 #else /* PSA_CRYPTO_DRIVER_PRESENT */
     (void) operation;
@@ -1011,7 +1011,7 @@
 #endif /* PSA_CRYPTO_DRIVER_TEST */
         default:
             /* Key is attached to a driver not known to us */
-            return( PSA_ERROR_BAD_STATE );
+            return( PSA_ERROR_INVALID_ARGUMENT );
     }
 #else /* PSA_CRYPTO_DRIVER_PRESENT */
     (void) operation;
@@ -1062,7 +1062,7 @@
 #endif /* PSA_CRYPTO_DRIVER_TEST */
         default:
             /* Operation is attached to a driver not known to us */
-            return( PSA_ERROR_BAD_STATE );
+            return( PSA_ERROR_INVALID_ARGUMENT );
     }
 #else /* PSA_CRYPTO_DRIVER_PRESENT */
     (void)operation;