php.net |  support |  documentation |  report a bug |  advanced search |  search howto |  statistics |  random bug |  login
Bug #32754 Segmentation fault when running xpath
Submitted: 2005-04-18 22:50 UTC Modified: 2005-04-19 02:07 UTC
From: php at max-imp dot com Assigned:
Status: Not a bug Package: DOM XML related
PHP Version: 5.0.4 OS: Red Hat
Private report: No CVE-ID: None
 [2005-04-18 22:50 UTC] php at max-imp dot com
Description:
------------
The code below causes a segmentation fault. The line it crashes on is
$nodelist = $xpath->query( '/*' );

The machine I have the problem on is running
PHP 5.0.4
libxml 2-2.6.19

On a different machine running the following we have no issues
PHP 5.0.4-dev
libxml 2.6.16

We have installed the newest snapshot of PHP as of the April 16th, but still had issues so we went back to PHP 5.0.4.

(There are a few notes in the code below.)

Thanks.


Reproduce code:
---------------
<?php
$x = new DOMDocument();


// This line gives a segmentation fault.
$x->loadXml( '<template xmlns="http://blah.com"/>');

// ... but if i comment the line above out and uncomment the next line there are no issues. It does not matter what xmlns is set to in the line above.
//$x->loadXml( '<template/>' );

$xpath = new DOMXPath( $x );
$nodelist = $xpath->query( '/*' );
?>

Expected result:
----------------
Nothing should really output in this example...but we expect no segmentation fault. :-)

Actual result:
--------------
Segmentation fault

This is what GDB gives me.
(gdb) run test.php
Starting program: /usr/local/bin/php test.php
[New Thread 1024 (LWP 18035)]

Program received signal SIGSEGV, Segmentation fault.
[Switching to Thread 1024 (LWP 18035)]
__pthread_mutex_lock (mutex=0x1528) at mutex.c:99
99      mutex.c: No such file or directory.
        in mutex.c
(gdb) bt
#0  __pthread_mutex_lock (mutex=0x1528) at mutex.c:99
#1  0x402d2974 in __libc_free (mem=0x83b22a0) at malloc.c:3152
#2  0x4020c4c6 in xmlFreePatParserContext (ctxt=0x83b22a0) at pattern.c:293
#3  0x4020e3ef in xmlPatterncompile (pattern=0x83aa3dc "/*", dict=0x0, flags=0, namespaces=0x83af450) at pattern.c:1899
#4  0x401b282b in xmlXPathTryStreamCompile (ctxt=0x83b0760, str=0x83aa3dc "/*") at xpath.c:11270
#5  0x401b2afa in xmlXPathEvalExpr (ctxt=0x83af268) at xpath.c:11452
#6  0x401b2d53 in xmlXPathEvalExpression (str=0x83aa3dc "/*", ctxt=0x83b0760) at xpath.c:11549
#7  0x0808f552 in zif_dom_xpath_query (ht=1, return_value=0x83af224, this_ptr=0x83b228c, return_value_used=1) at /home/krisw/php-5.0.4/ext/dom/xpath.c:198
#8  0x4040b7e1 in get_module () from /usr/local/Zend/lib/Optimizer-2.5.7/php-5.0.x/ZendOptimizer.so
#9  0x4041985a in zend_oe () from /usr/local/Zend/lib/Optimizer-2.5.7/php-5.0.x/ZendOptimizer.so
#10 0x081714ee in php_execute_script (primary_file=0xbfffe0e0) at /home/krisw/php-5.0.4/main/main.c:1632
#11 0x081dd1e0 in main (argc=2, argv=0xbfffe184) at /home/krisw/php-5.0.4/sapi/cli/php_cli.c:946
#12 0x40272306 in __libc_start_main (main=0x81dc888 <main>, argc=2, ubp_av=0xbfffe184, init=0x807a580 <_init>, fini=0x81f9f10 <_fini>,
    rtld_fini=0x4000d2cc <_dl_fini>, stack_end=0xbfffe17c) at ../sysdeps/generic/libc-start.c:129
(gdb)


Patches

Pull Requests

History

AllCommentsChangesGit/SVN commitsRelated reports
 [2005-04-19 02:04 UTC] php at max-imp dot com
Installing libxml 2.6.16 seems to have solved the issue. There seems to be some incompatibility issue between PHP 5.0.4 and libxml 2.6.19
 [2005-04-19 02:07 UTC] rrichards@php.net
Do not file bugs when you have Zend extensions (zend_extension=)
loaded. Examples are Zend Optimizer, Zend Debugger, Turck MM Cache,
APC, Xdebug and ionCube loader.  These extensions often modify engine
behavior which is not related to PHP itself.


 
PHP Copyright © 2001-2024 The PHP Group
All rights reserved.
Last updated: Wed Dec 04 19:01:32 2024 UTC