diff --git a/core/lib/Drupal/Core/Entity/EntityPermissionProvider.php b/core/lib/Drupal/Core/Entity/EntityPermissionProvider.php
index b47b0ba..f8b9d5b 100644
--- a/core/lib/Drupal/Core/Entity/EntityPermissionProvider.php
+++ b/core/lib/Drupal/Core/Entity/EntityPermissionProvider.php
@@ -92,12 +92,16 @@ public function buildPermissions(EntityTypeInterface $entity_type) {
       ];
     }
     // Generate the other permissions based on granularity.
-    if ($entity_type->getPermissionGranularity() == 'entity_type') {
+    $entity_type_permission_granularity = $entity_type->getPermissionGranularity();
+    if ($entity_type_permission_granularity === 'entity_type') {
       $permissions += $this->buildEntityTypePermissions($entity_type);
     }
-    else {
+    else if ($entity_type_permission_granularity == 'bundle') {
       $permissions += $this->buildBundlePermissions($entity_type);
     }
+    else {
+      throw new EntityMalformedException('The entity type does not have an valid permission_granularity.');
+    }
 
     foreach ($permissions as $name => $permission) {
       $permissions[$name] += [