diff --git a/core/lib/Drupal/Core/Entity/EntityTypeInterface.php b/core/lib/Drupal/Core/Entity/EntityTypeInterface.php
index 17d9555..650eefc 100644
--- a/core/lib/Drupal/Core/Entity/EntityTypeInterface.php
+++ b/core/lib/Drupal/Core/Entity/EntityTypeInterface.php
@@ -17,6 +17,8 @@
  */
 interface EntityTypeInterface {
 
+  const BUNDLE_MAX_LENGTH = 32;
+
   /**
    * Gets any arbitrary property.
    *
diff --git a/core/modules/comment/comment.module b/core/modules/comment/comment.module
index d9d86d4..f2fe09c 100644
--- a/core/modules/comment/comment.module
+++ b/core/modules/comment/comment.module
@@ -12,8 +12,12 @@
 
 use Drupal\comment\CommentInterface;
 use Drupal\comment\Plugin\Field\FieldType\CommentItemInterface;
+use Drupal\Component\Utility\String;
+use Drupal\Component\Utility\Unicode;
 use Drupal\Core\Entity\EntityInterface;
 use Drupal\Core\Entity\Display\EntityViewDisplayInterface;
+use Drupal\Core\Entity\EntityMalformedException;
+use Drupal\Core\Entity\EntityTypeInterface;
 use Drupal\Core\Url;
 use Drupal\field\FieldInstanceConfigInterface;
 use Drupal\field\FieldConfigInterface;
@@ -781,6 +785,26 @@ function comment_form_field_ui_field_overview_form_alter(&$form, $form_state) {
   if ($form['#entity_type'] == 'comment' && $request->attributes->has('commented_entity_type')) {
     $form['#title'] = \Drupal::service('comment.manager')->getFieldUIPageTitle($request->attributes->get('commented_entity_type'), $request->attributes->get('field_name'));
   }
+  $form['#validate'][] = 'comment_field_ui_overview_form_validate';
+}
+
+/**
+ * Form validation callback for field_ui_field_overview_form().
+ */
+function comment_field_ui_overview_form_validate(&$form, $form_state) {
+  $commented_entity_type_id = $form['#entity_type'];
+  $field_name = $form_state['values']['fields']['_add_new_field']['field_name'];
+  $type = $form_state['values']['fields']['_add_new_field']['field_name']['type'];
+  if ($type != 'comment') {
+    return;
+  }
+  $new_bundle = $commented_entity_type_id . '__' . $field_name;
+  if (Unicode::strlen($new_bundle) > EntityTypeInterface::BUNDLE_MAX_LENGTH) {
+    $this->setFormError('fields][_add_new_field][field_name', $form_state, $this->t('Add new field: The provided field name would exceed the maximum allowable length for a comment field on the %type entity type.', array(
+      '%type' => $commented_entity_type_id,
+    )));
+  }
+
 }
 
 /**
@@ -902,6 +926,25 @@ function comment_entity_predelete(EntityInterface $entity) {
 }
 
 /**
+ * Implements hook_entity_presave().
+ */
+function comment_entity_presave(EntityInterface $entity) {
+  if ($entity->getEntityTypeId() == 'field_config' && $entity->type == 'comment') {
+    $commented_entity_type = $entity->entity_type;
+    $field_name = $entity->name;
+    $bundle = $commented_entity_type . '__' . $field_name;
+    if (Unicode::strlen($bundle) > EntityTypeInterface::BUNDLE_MAX_LENGTH) {
+      throw new EntityMalformedException(t('You cannot create a comment field named %field_name on the %type Entity type, please select a shorter name such as %name',
+      array(
+        '%field_name' => $field_name,
+        '%type' => $commented_entity_type,
+        '%name' => substr($field_name, 0, EntityTypeInterface::BUNDLE_MAX_LENGTH - Unicode::strlen($bundle)),
+      )));
+    }
+  }
+}
+
+/**
  * Implements hook_node_update_index().
  */
 function comment_node_update_index(EntityInterface $node, $langcode) {