CFileValidator double filesize error

Don’t know it is normal behavior when uploading to large file:

My php.ini upload_max_filesize is 20M

My validation rules are set for 15M

public function rules()


        return array(

            array('plik', 'file', 'allowEmpty'=>false),

            array('plik', 'file', 'maxSize'=>(15*1024*1024)),



When I’m trying to upload for example 30M file I get two erros:

Shouldn’t only lowest value trigger error?

One more thing when uploaded file exceded post_max_size which is 64M for my settings I get no error and my app frozen.