php：// input中的数据不等于解析并放在$ _POST中的数据

Question

I'm working out this odd bug in Wordpress, and I don't know how wordpress works, but I ran around for an hour trying to isolate the problem and see where the root of the issue comes from.

Turns out the problem is that the thing isn't updating because $_POST does not have the data that is being requested.

At the top of the file that I'm accessing from the browser, before any other code, I did the following:

echo file_get_contents("php://input");
print_r($_POST); exit();

I see that wordpress uses $_POST as a catch-all global and writes to it as well. I thought maybe wordpress kicks the data out somewhere but I couldn't find that. This is at the top of the file anyways, before anything else happens at all.. I don't think it's even possible for the variables to be modified before that

The output from that is

widget-text%5B3%5D%5Btitle%5D=Test&widget-text%5B3%5D%5Btext%5D=THISISATEST&sidebar=sidebar-1&sidebar-1_position=1&sidebar-2_position=&sidebar-3_position=&sidebar-4_position=&sidebar-5_position=&savewidget=Save+Widget&widget-id=text-3&id_base=text&multi_number=3&_wpnonce=36852083b6&_wp_http_referer=%2Fwp-admin%2Fwidgets.php%3Fmessage%3D0%26editwidget%3Dtext-3%26sidebar%3Dsidebar-1%26key%3D0
Array
(
    [widget-text] => Array
        (
            [3] => Array
                (
                    [title] => Test
                )

        )

    [sidebar] => sidebar-1
    [sidebar-1_position] => 1
    [sidebar-2_position] => 
    [sidebar-3_position] => 
    [sidebar-4_position] => 
    [sidebar-5_position] => 
    [savewidget] => Save Widget
    [widget-id] => text-3
    [id_base] => text
    [multi_number] => 3
    [_wpnonce] => 36852083b6
    [_wp_http_referer] => /wp-admin/widgets.php?message=0&editwidget=text-3&sidebar=sidebar-1&key=0
)

url_decoded:

widget-text[3][title]=Test&widget-text[3][text]=THISISATEST&sidebar=sidebar-1&sidebar-1_position=1&sidebar-2_position=&sidebar-3_position=&sidebar-4_position=&sidebar-5_position=&savewidget=Save Widget&widget-id=text-3&id_base=text&multi_number=3&_wpnonce=36852083b6&_wp_http_referer=/wp-admin/widgets.php?message=0&editwidget=text-3&sidebar=sidebar-1&key=0Array

Note how in the raw data, widget-text[3][text]=THISISATEST exists. But $_POST['widget-text']['3']['text'] is undefined.

I looked through phpinfo and can't find any relevant settings. I am on PHP Version 5.3.8, Apache 2, I'm running suse on AWS.

Does anyone have any ideas on how to make $_POST parse the raw data correctly?

Answer 1

This is indeed weird. Could be a bug in PHP or issue with configuration/extension.

1. Try changing configuration variables max_input_nesting_level, max_input_vars, max_input_time. If you're unsure about values just try default ones. Check the PHP documentation page to look up default values and their meaning.

2. If you're running suhosin extension, try disabling it and see if it helps. Also all suhosin.post.* configuration keys look interesting.

3. Googling reveals similar problems: one, two.

4. Try accessing it through $_REQUEST - $_REQUEST['widget-text']['3']['text']

Anyway, after some googling it seems like this happens in PHP 5.3.8. So upgrading may be another option.