Index: media.php
===================================================================
--- media.php	(revision 31233)
+++ media.php	(working copy)
@@ -3311,10 +3311,14 @@
 		"SELECT post_id FROM $wpdb->postmeta WHERE meta_key = '_wp_attached_file' AND meta_value = %s",
 		$path
 	);
+
 	$post_id = $wpdb->get_var( $sql );
+
 	if ( ! empty( $post_id ) ) {
 		return (int) $post_id;
 	}
+
+	return 0;
 }
 
 /**