ID: 47376 Updated by: fel...@php.net Reported By: pahan at hubbitus dot spb dot su Status: Bogus Bug Type: PCRE related Operating System: Linux PHP Version: 5.3.0beta1 New Comment:
It's a known PCRE issue, and is documented: http://www.manpagez.com/man/3/pcrestack/ Previous Comments: ------------------------------------------------------------------------ [2009-02-13 10:01:29] fel...@php.net Your pattern could be: /(@@ -[\d,]+ \+[\d,]+ @@\s)(?1)+/ ------------------------------------------------------------------------ [2009-02-13 09:01:51] pahan at hubbitus dot spb dot su Thank you for the links it was pretty usefully. I'm read information on it. Very strange read PHP documentation like: ====QUOTE:http://ru.php.net/manual/en/pcre.configuration.php==== pcre.recursion_limit integer PCRE's recursion limit. Please note that if you set this value to a *high number you may consume all the available process stack and eventually crash PHP* (due to reaching the stack size limit imposed by the Operating System). ====/QUOTE==== Really you can't provide any runtime check and provide standard way to handle errors (or warnings)??? So, this low level limitation may be in pcre, but crash of PHP is PHP BUG in any case! And, If you a interesting, I'm make more investigation on this theme: On default OS limit: $ ulimit -s 10240 example script behaves as: //ini_set('pcre.recursion_limit', 9939);//Segmentation fault //ini_set('pcre.recursion_limit', 9938);//Work So, If I increase stack size on my system: $ ulimit -s 65536 all work fine, as expected!!! ------------------------------------------------------------------------ [2009-02-13 00:53:14] fel...@php.net It isn't a PHP bug. See bug#33468, bug#39387. Thanks. ------------------------------------------------------------------------ [2009-02-12 22:51:08] pahan at hubbitus dot spb dot su Sorry, sorry. Off course line "$text = file();" in reproduce code unnecessary. Please remove it. ------------------------------------------------------------------------ [2009-02-12 22:12:28] pahan at hubbitus dot spb dot su Description: ------------ On text, where search pattern repeated many times (>643 times by test) php segfaulted (Core dump you may download here: http://ru.bir.ru/_temp/php-pcre-bug/core.8729 ) on preg_replace. So, if we reduce length of test text ( http://ru.bir.ru/_temp/php-pcre-bug/pcre_bug.text ) on 1 line, or just limit repetition on 1 - it is worked. All Zend-modules was disabled. Reproduce code: --------------- <? $text = file_get_contents('pcre_bug.text'); echo preg_replace('/(@@ -[\d,]+ \+[\d,]+ @@\s){2,}/s', '-some data-', $text); //Segmentation fault $text = file(); # Interesting: #echo preg_replace('/(@@ -[\d,]+ \+[\d,]+ @@\s){2,642}/s', '-some data-', $text); //Work, but result it is not same as needed. #echo preg_replace('/(@@ -[\d,]+ \+[\d,]+ @@\s){2,643}/s', '-some data-', $text); //PHP Warning: preg_replace(): Compilation failed: regular expression is too large at offset 33 ?> Expected result: ---------------- Work as when text is less. Actual result: -------------- Segmentation fault ------------------------------------------------------------------------ -- Edit this bug report at http://bugs.php.net/?id=47376&edit=1
