#50264 [NEW]: Possible pcre memory leak

From: laszlo dot janszky at gmail dot com Operating system: Windows XP PHP version: 5.3.1 PHP Bug Type: PCRE related Bug description: Possible pcre memory leak Description: ------------ I have a huge recursive regex (about 500bytes), which needs a lot of memory for backtrace. The regex matches on templates like {command1 arg1=$arg1 arg2=$arg2|modifier2 arg3="text"|modifier3:modarg31:modarg32} etc.... If I use the regex with preg_match_all, then the backtrace memory usage depends on the count of the commands superexponential. So: R^2 = 0,9977 (R^2 for trendline) ln ln M = 0,0787 * N + 1,9304 [M] = used backtrack memory in bytes [N] = number of command calls It don't think that more than 1Mb memory usage is normal for a 0.0002Mb string. The recursion memory usage is normal(under 1kb). I'm pretty disappointed because I can't use my template engine because of a badly written pcre engine. Reproduce code: --------------- $template1=' {display var=$link} {display var=$link} {display var=$link} {display var=$link} {display var=$link} {display var=$link} {display var=$link} {display var=$link} {display var=$link} {display var=$link} '; $template2=' {display var=$link} {display var=$link} {display var=$link} {display var=$link} test test test test test test test test test test test test test test test test test test test test test test test test test test test test test test test test test test test test test test test test test test test test test test test test test test '; $regex='%\\{(?<function>(?:\\w+))(?:(?<list>\\s(?:[\\w_]+(?:\\s[\\w_]+)*\\s)?(?:\\$\\w+(?:->\\w+|\\.\\w+)*|"(?:.*?)"|\\d+(?:\\.\\d+)?)(?:\\|\\w+(?::(?:\\$\\w+(?:->\\w+|\\.\\w+)*|"(?:.*?)"|\\d+(?:\\.\\d+)?))*)*(?:\\s[\\w_]+(?:\\s[\\w_]+)*\\s(?:\\$\\w+(?:->\\w+|\\.\\w+)*|"(?:.*?)"|\\d+(?:\\.\\d+)?)(?:\\|\\w+(?::(?:\\$\\w+(?:->\\w+|\\.\\w+)*|"(?:.*?)"|\\d+(?:\\.\\d+)?))*)*)*(?:\\s[\\w_]+(?:\\s[\\w_]+)*)?)|(?<hash>(?:\\s\\w+=(?:\\$\\w+(?:->\\w+|\\.\\w+)*|"(?:.*?)"|\\d+(?:\\.\\d+)?)(?:\\|\\w+(?::(?:\\$\\w+(?:->\\w+|\\.\\w+)*|"(?:.*?)"|\\d+(?:\\.\\d+)?))*)*)*))(?:\\}(?<block>.*?(?:(?0).*?)*?)\\{/(?P=function))?\\}%usD'; $one_Mb=1024*1024; $one_kb=1024; ini_set('pcre.backtrack_limit', $one_Mb); ini_set('pcre.recursion_limit', $one_kb); preg_match_all($regex,$template1,$matches1,PREG_SET_ORDER); preg_match_all($regex,$template2,$matches2,PREG_SET_ORDER); echo 'test1:<br />'; echo (!count($matches1)?'failed':'ok').'<br />'; echo 'test2:<br />'; echo (!count($matches2)?'failed':'ok').'<br />'; Expected result: ---------------- test1: ok test2: ok Actual result: -------------- test1: failed test2: ok -- Edit bug report at http://bugs.php.net/?id=50264&edit=1 -- Try a snapshot (PHP 5.2): http://bugs.php.net/fix.php?id=50264&r=trysnapshot52 Try a snapshot (PHP 5.3): http://bugs.php.net/fix.php?id=50264&r=trysnapshot53 Try a snapshot (PHP 6.0): http://bugs.php.net/fix.php?id=50264&r=trysnapshot60 Fixed in SVN: http://bugs.php.net/fix.php?id=50264&r=fixed Fixed in SVN and need be documented: http://bugs.php.net/fix.php?id=50264&r=needdocs Fixed in release: http://bugs.php.net/fix.php?id=50264&r=alreadyfixed Need backtrace: http://bugs.php.net/fix.php?id=50264&r=needtrace Need Reproduce Script: http://bugs.php.net/fix.php?id=50264&r=needscript Try newer version: http://bugs.php.net/fix.php?id=50264&r=oldversion Not developer issue: http://bugs.php.net/fix.php?id=50264&r=support Expected behavior: http://bugs.php.net/fix.php?id=50264&r=notwrong Not enough info: http://bugs.php.net/fix.php?id=50264&r=notenoughinfo Submitted twice: http://bugs.php.net/fix.php?id=50264&r=submittedtwice register_globals: http://bugs.php.net/fix.php?id=50264&r=globals PHP 4 support discontinued: http://bugs.php.net/fix.php?id=50264&r=php4 Daylight Savings: http://bugs.php.net/fix.php?id=50264&r=dst IIS Stability: http://bugs.php.net/fix.php?id=50264&r=isapi Install GNU Sed: http://bugs.php.net/fix.php?id=50264&r=gnused Floating point limitations: http://bugs.php.net/fix.php?id=50264&r=float No Zend Extensions: http://bugs.php.net/fix.php?id=50264&r=nozend MySQL Configuration Error: http://bugs.php.net/fix.php?id=50264&r=mysqlcfg