如何修复因不正确的字节计数长度而损坏的序列化字符串？

php serialization mysql content-management-system

2022-08-30 07:27:31

我正在将Hotaru CMS与图像上传插件一起使用，如果我尝试将图像附加到帖子，则会出现此错误，否则没有错误：

unserialize（） [function.unserialize]：偏移处的错误

有问题的代码（错误指向与 **一行）：

/**
     * Retrieve submission step data
     *
     * @param $key - empty when setting
     * @return bool
     */
    public function loadSubmitData($h, $key = '')
    {
        // delete everything in this table older than 30 minutes:
        $this->deleteTempData($h->db);

        if (!$key) { return false; }

        $cleanKey = preg_replace('/[^a-z0-9]+/','',$key);
        if (strcmp($key,$cleanKey) != 0) {
            return false;
        } else {
            $sql = "SELECT tempdata_value FROM " . TABLE_TEMPDATA . " WHERE tempdata_key = %s ORDER BY tempdata_updatedts DESC LIMIT 1";
            $submitted_data = $h->db->get_var($h->db->prepare($sql, $key));
            **if ($submitted_data) { return unserialize($submitted_data); } else { return false; }** 
        }
    }

来自表格的数据，请注意末尾位有图像信息，我不是PHP专家，所以我想知道你们/gals会怎么想？

tempdata_value：

a:10:{s:16:"submit_editorial";b:0;s:15:"submit_orig_url";s:13:"www.bbc.co.uk";s:12:"submit_title";s:14:"No title found";s:14:"submit_content";s:12:"dnfsdkfjdfdf";s:15:"submit_category";i:2;s:11:"submit_tags";s:3:"bbc";s:9:"submit_id";b:0;s:16:"submit_subscribe";i:0;s:15:"submit_comments";s:4:"open";s:5:"image";s:19:"C:fakepath100.jpg";}

编辑：我想我已经找到了序列化位...

/**
     * Save submission step data
     *
     * @return bool
     */
    public function saveSubmitData($h)
    {
        // delete everything in this table older than 30 minutes:
        $this->deleteTempData($h->db);

        $sid = preg_replace('/[^a-z0-9]+/i', '', session_id());
        $key = md5(microtime() . $sid . rand());
        $sql = "INSERT INTO " . TABLE_TEMPDATA . " (tempdata_key, tempdata_value, tempdata_updateby) VALUES (%s,%s, %d)";
        $h->db->query($h->db->prepare($sql, $key, serialize($h->vars['submitted_data']), $h->currentUser->id));
        return $key;
    }

答案 1

unserialize() [function.unserialize]: Error at offset由于长度无效而致invalid serialization data

快速修复

您可以做的是序列化数组中的元素recalculating the length

您当前的序列化数据

$data = 'a:10:{s:16:"submit_editorial";b:0;s:15:"submit_orig_url";s:13:"www.bbc.co.uk";s:12:"submit_title";s:14:"No title found";s:14:"submit_content";s:12:"dnfsdkfjdfdf";s:15:"submit_category";i:2;s:11:"submit_tags";s:3:"bbc";s:9:"submit_id";b:0;s:16:"submit_subscribe";i:0;s:15:"submit_comments";s:4:"open";s:5:"image";s:19:"C:fakepath100.jpg";}';

无需重新计算的示例

var_dump(unserialize($data));

输出

Notice: unserialize() [function.unserialize]: Error at offset 337 of 338 bytes

重新计算

$data = preg_replace('!s:(\d+):"(.*?)";!e', "'s:'.strlen('$2').':\"$2\";'", $data);
var_dump(unserialize($data));

输出

array
  'submit_editorial' => boolean false
  'submit_orig_url' => string 'www.bbc.co.uk' (length=13)
  'submit_title' => string 'No title found' (length=14)
  'submit_content' => string 'dnfsdkfjdfdf' (length=12)
  'submit_category' => int 2
  'submit_tags' => string 'bbc' (length=3)
  'submit_id' => boolean false
  'submit_subscribe' => int 0
  'submit_comments' => string 'open' (length=4)
  'image' => string 'C:fakepath100.jpg' (length=17)

建议..我

而不是使用这种快速修复...我会建议你更新问题

如何序列化数据
你如何保存它 ..

================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================

错误

生成错误是因为使用双引号而不是单引号，这就是为什么转换为"'C:\fakepath\100.pngC:fakepath100.jpg

修复错误

你需要改变从（注意单一相当$h->vars['submitted_data']' )

取代

 $h->vars['submitted_data']['image'] = "C:\fakepath\100.png" ;

跟

 $h->vars['submitted_data']['image'] = 'C:\fakepath\100.png' ;

附加过滤器

您还可以在调用序列化之前添加此简单筛选器

function satitize(&$value, $key)
{
    $value = addslashes($value);
}

array_walk($h->vars['submitted_data'], "satitize");

如果您有 UTF 字符，您也可以运行

 $h->vars['submitted_data'] = array_map("utf8_encode",$h->vars['submitted_data']);

如何在将来的序列化数据中检测问题

  findSerializeError ( $data1 ) ;

输出

Diffrence 9 != 7
    -> ORD number 57 != 55
    -> Line Number = 315
    -> Section Data1  = pen";s:5:"image";s:19:"C:fakepath100.jpg
    -> Section Data2  = pen";s:5:"image";s:17:"C:fakepath100.jpg
                                            ^------- The Error (Element Length)

findSerializeError功能

function findSerializeError($data1) {
    echo "<pre>";
    $data2 = preg_replace ( '!s:(\d+):"(.*?)";!e', "'s:'.strlen('$2').':\"$2\";'",$data1 );
    $max = (strlen ( $data1 ) > strlen ( $data2 )) ? strlen ( $data1 ) : strlen ( $data2 );

    echo $data1 . PHP_EOL;
    echo $data2 . PHP_EOL;

    for($i = 0; $i < $max; $i ++) {

        if (@$data1 {$i} !== @$data2 {$i}) {

            echo "Diffrence ", @$data1 {$i}, " != ", @$data2 {$i}, PHP_EOL;
            echo "\t-> ORD number ", ord ( @$data1 {$i} ), " != ", ord ( @$data2 {$i} ), PHP_EOL;
            echo "\t-> Line Number = $i" . PHP_EOL;

            $start = ($i - 20);
            $start = ($start < 0) ? 0 : $start;
            $length = 40;

            $point = $max - $i;
            if ($point < 20) {
                $rlength = 1;
                $rpoint = - $point;
            } else {
                $rpoint = $length - 20;
                $rlength = 1;
            }

            echo "\t-> Section Data1  = ", substr_replace ( substr ( $data1, $start, $length ), "<b style=\"color:green\">{$data1 {$i}}</b>", $rpoint, $rlength ), PHP_EOL;
            echo "\t-> Section Data2  = ", substr_replace ( substr ( $data2, $start, $length ), "<b style=\"color:red\">{$data2 {$i}}</b>", $rpoint, $rlength ), PHP_EOL;
        }

    }

}

保存到数据库的更好方法

$toDatabse = base64_encode(serialize($data));  // Save to database
$fromDatabase = unserialize(base64_decode($data)); //Getting Save Format

答案 2

我没有足够的声誉来评论，所以我希望使用上述“正确”答案的人能看到这一点：

从 php 5.5 开始，preg_replace（）中的 /e 修饰符已被完全弃用，上面的preg_match将出错。php文档建议使用preg_match_callback代替它。

请找到以下解决方案，作为上述建议preg_match的替代方法。

$fixed_data = preg_replace_callback ( '!s:(\d+):"(.*?)";!', function($match) {      
    return ($match[1] == strlen($match[2])) ? $match[0] : 's:' . strlen($match[2]) . ':"' . $match[2] . '";';
},$bad_data );