Bug #55035 [NEW]: pcre_exec() deadlock causing Segmentation fault (11)

From: Operating system: Ubuntu 11.04 and Trisquel 4.5 PHP version: 5.3.6 Package: PCRE related Bug Type: Bug Bug description:pcre_exec() deadlock causing Segmentation fault (11) Description: ------------ It appears that PHP can deadlock in pcre_exec(), repeatingly calling a function(itself?). Was converting a vBulletin forum to phpBB, therefore might be hard to reproduce. Despite that I managed to reproduce it on three different computers. I spent several hours debugging this, and will dig deeper into the code that caused this problem to find the specific string causing this. Expect more debug data soon. Test script: --------------- phpBB 3.0.8, converting from vBulletin 3.8.x, with code attached to http://www.phpbb.com/community/viewtopic.php?f=65&t=1722325#p10391895 You also need a database to convert. Expected result: ---------------- Normal phpBB progress when converting (php deliving an HTML page) Actual result: -------------- PHP delivered a blank php script file to the browser and apache logged a segfault (11). After a very long session trying to debug this I finally managed to generate a stacktrace with gdb. The resource below will be accessible as long as this bug is unresolved. http://jimmy.axenhus.com/gdb.txt -- Edit bug report at http://bugs.php.net/bug.php?id=55035&edit=1 -- Try a snapshot (PHP 5.2): http://bugs.php.net/fix.php?id=55035&r=trysnapshot52 Try a snapshot (PHP 5.3): http://bugs.php.net/fix.php?id=55035&r=trysnapshot53 Try a snapshot (trunk): http://bugs.php.net/fix.php?id=55035&r=trysnapshottrunk Fixed in SVN: http://bugs.php.net/fix.php?id=55035&r=fixed Fixed in SVN and need be documented: http://bugs.php.net/fix.php?id=55035&r=needdocs Fixed in release: http://bugs.php.net/fix.php?id=55035&r=alreadyfixed Need backtrace: http://bugs.php.net/fix.php?id=55035&r=needtrace Need Reproduce Script: http://bugs.php.net/fix.php?id=55035&r=needscript Try newer version: http://bugs.php.net/fix.php?id=55035&r=oldversion Not developer issue: http://bugs.php.net/fix.php?id=55035&r=support Expected behavior: http://bugs.php.net/fix.php?id=55035&r=notwrong Not enough info: http://bugs.php.net/fix.php?id=55035&r=notenoughinfo Submitted twice: http://bugs.php.net/fix.php?id=55035&r=submittedtwice register_globals: http://bugs.php.net/fix.php?id=55035&r=globals PHP 4 support discontinued: http://bugs.php.net/fix.php?id=55035&r=php4 Daylight Savings: http://bugs.php.net/fix.php?id=55035&r=dst IIS Stability: http://bugs.php.net/fix.php?id=55035&r=isapi Install GNU Sed: http://bugs.php.net/fix.php?id=55035&r=gnused Floating point limitations: http://bugs.php.net/fix.php?id=55035&r=float No Zend Extensions: http://bugs.php.net/fix.php?id=55035&r=nozend MySQL Configuration Error: http://bugs.php.net/fix.php?id=55035&r=mysqlcfg