From: valvatne at pvv dot org
Operating system: RedHat Linux 9 - Kernel 2.4.20-8
PHP version: 4CVS-2004-03-08 (stable)
PHP Bug Type: Reproducible crash
Bug description: preg_match segfaults on certain patterns involving lookahead
assertions
Description:
------------
PHP segfaults when running preg_match() with a simple pattern intended to
match any sequence of characters which are not followed by a given
character (lookahead assertion). The segfault only happens if the string
being matched approaches 10k characters in length, but at that point it
seems to be 100% reproducible.
Config line:
./configure --with-apxs2=/usr/local/apache2/bin/apxs --with-mysql
--with-pgsql --enable-sockets --enable-debug
Reproduce code:
---------------
$strlen = 10000;
$string = '';
for($i=0;$i<$strlen;$i++) {
$string .= "a";
}
$pattern = '/(.(?!b))*/';
echo preg_match($pattern, $string);
Expected result:
----------------
1
Actual result:
--------------
Segmentation fault. I can't seem to get gdb to behave right now, so if
someone else could reproduce the bug and post a backtrace, that would be
nice.
--
Edit bug report at http://bugs.php.net/?id=27525&edit=1
--
Try a CVS snapshot (php4): http://bugs.php.net/fix.php?id=27525&r=trysnapshot4
Try a CVS snapshot (php5): http://bugs.php.net/fix.php?id=27525&r=trysnapshot5
Fixed in CVS: http://bugs.php.net/fix.php?id=27525&r=fixedcvs
Fixed in release: http://bugs.php.net/fix.php?id=27525&r=alreadyfixed
Need backtrace: http://bugs.php.net/fix.php?id=27525&r=needtrace
Need Reproduce Script: http://bugs.php.net/fix.php?id=27525&r=needscript
Try newer version: http://bugs.php.net/fix.php?id=27525&r=oldversion
Not developer issue: http://bugs.php.net/fix.php?id=27525&r=support
Expected behavior: http://bugs.php.net/fix.php?id=27525&r=notwrong
Not enough info: http://bugs.php.net/fix.php?id=27525&r=notenoughinfo
Submitted twice: http://bugs.php.net/fix.php?id=27525&r=submittedtwice
register_globals: http://bugs.php.net/fix.php?id=27525&r=globals
PHP 3 support discontinued: http://bugs.php.net/fix.php?id=27525&r=php3
Daylight Savings: http://bugs.php.net/fix.php?id=27525&r=dst
IIS Stability: http://bugs.php.net/fix.php?id=27525&r=isapi
Install GNU Sed: http://bugs.php.net/fix.php?id=27525&r=gnused
Floating point limitations: http://bugs.php.net/fix.php?id=27525&r=float
