#30186 [Fbk->NoF]: passing empty string to xml_parser_create causes 100% CPU utilization

ID: 30186 Updated by: php-bugs@lists.php.net Reported By: johnkarl at nbnet dot nb dot ca -Status: Feedback +Status: No Feedback Bug Type: XML related Operating System: Windows 2000 Professional SP4 PHP Version: 5.0.1 New Comment: No feedback was provided for this bug for over a week, so it is being suspended automatically. If you are able to provide the information that was originally requested, please do so and change the status of the bug back to "Open". Previous Comments: ------------------------------------------------------------------------ [2005-02-12 22:50:00] tony2001@php.net Please try using this CVS snapshot: http://snaps.php.net/php5-STABLE-latest.tar.gz For Windows: http://snaps.php.net/win32/php5.0-win32-latest.zip ------------------------------------------------------------------------ [2004-09-27 20:23:11] johnkarl at nbnet dot nb dot ca Just tried it out with the snapshot you provided and still the same problem. Here are my specs: Windows 2004 Professional SP4 Apache/2.0.49 My workaround is to check the PHP version, and omit the empty string parameter if version >= 5 This isn't an isolated problem, either. I became aware of this through several individuals using my open source libraries. I'm not certain what they were running but I can proably find out if you can't replicate the problem. John ------------------------------------------------------------------------ [2004-09-27 19:47:43] iliaa@php.net Please try using this CVS snapshot: http://snaps.php.net/php5-STABLE-latest.tar.gz For Windows: http://snaps.php.net/win32/php5.0-win32-latest.zip Seems to work fine in recent code. ------------------------------------------------------------------------ [2004-09-21 21:11:55] johnkarl at nbnet dot nb dot ca Description: ------------ In PHP5, if xml_parser_create is called with an empty string as the character encoding parameter, a server will utilize 100% of the CPU. Restarting Apache will sometimes cause the system to revert to normal, but usually a reboot is needed. In PHP4, calling xml_parser_create("") will cause Expat to autodetect the character encoding. In the user comments of www.php.net, this is purportedly true of PHP5 as well; however this is not the case. This problem has been reproduced on a number of other machines as well. I'm not sure if the same happens with IIS. Reproduce code: --------------- $parser = xml_parser_create(""); Expected result: ---------------- a reference to the parser should be returned Actual result: -------------- Apache stalls, 100% CPU usage ------------------------------------------------------------------------ -- Edit this bug report at http://bugs.php.net/?id=30186&edit=1