The following can be  implemented to get the user details 

    global $user;
    $user->field_f_name[LANGUAGE_NONE][0]['value'] ;
    $user->field_l_name[LANGUAGE_NONE][0]['value'] ;
    $user->field_phone[LANGUAGE_NONE][0]['value'] ;
    $user->field_address[LANGUAGE_NONE][0]['value']