How validation laravel array validation and display message with input field

1. How validate and display validate message in small tag

<div class="checkbox">
      @foreach($permissions as $permission)
          <li><input type="checkbox" value="" name="permissions[]" class="flat"> </li>
      @endforeach
 </div>
<small class="text-danger"></small>

controller Code

 'permissions' => 'required',

via Chebli Mohamed