Segmentation fault (access null pointer) in ext/libxml/libxml.c

[YuanchengJiang]

Description

The following code:

<?php
  $dom = new DOMDocument;
  $dom->loadHTML('<span title=""y">x</span><span title=""z">x</span>');
  $html = simplexml_import_dom($dom);
  foreach ($html->body->span as $obj) {
  }
  $script1_dataflow = $html;
  $array = ['foo'];
  foreach ($array as $key => &$value) {
    unset($script1_dataflow[$key]);
  }

Resulted in this output:

Segmentation fault (core dumped)

UBSan:

/php-src/ext/libxml/libxml.c:333:16: runtime error: member access within null pointer of type 'php_libxml_node_object' (aka 'struct _php_libxml_node_object')
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior /php-src/ext/libxml/libxml.c:333:16

PHP Version

PHP 8.4.0-dev

Operating System

ubuntu 22.04