SonataUserBundle/Resources/config/security_acl.xml

<?xml version="1.0" encoding="UTF-8"?>

<container xmlns="http://symfony.com/schema/dic/services"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://symfony.com/schema/dic/services http://symfony.com/schema/dic/services/services-1.0.xsd">

    <parameters>
        <parameter key="security.acl.user_voter.class">Sonata\UserBundle\Security\Authorization\Voter\UserAclVoter</parameter>
    </parameters>

    <services>
        <service id="security.acl.voter.user_permissions" class="%security.acl.user_voter.class%" public="false">
            <tag name="monolog.logger" channel="security" />
            <argument type="service" id="security.acl.provider" />
            <argument type="service" id="security.acl.object_identity_retrieval_strategy" />
            <argument type="service" id="security.acl.security_identity_retrieval_strategy" />
            <argument type="service" id="security.acl.permission.map" />
            <argument type="service" id="logger" on-invalid="null" />
            <tag name="security.voter" priority="255" />
        </service>
    </services>    
</container>