private function validateFilePath($form, $dirs)
    {
        foreach ($form->getData() as $fileName) {
            $fileInDir = array_filter($dirs, function ($dir) use ($fileName) {
                $filePath = realpath($dir.'/'.$fileName);
                $topDirPath = realpath($dir);
                return strpos($filePath, $topDirPath) === 0 && $filePath !== $topDirPath;
            });
            if (!$fileInDir) {
                $form->getRoot()['product_image']->addError(new FormError(trans('admin.product.image__invalid_path')));
            }
        }
    }