Bug #63369 [Opn->Csd]: (un)serialize() leaves dangling pointers, causes crashes

Edit report at https://bugs.php.net/bug.php?id=63369&edit=1 ID: 63369 Updated by: tony2001@php.net Reported by: tony2001@php.net Summary: (un)serialize() leaves dangling pointers, causes crashes -Status: Open +Status: Closed Type: Bug Package: Reproducible crash Operating System: * PHP Version: 5.4Git-2012-10-26 (Git) Block user comment: N Private report: N New Comment: Automatic comment on behalf of tony2001 Revision: http://git.php.net/?p=php-src.git;a=commit;h=f2bffdc2e48174e38a059d425953e8b1c08dd4bf Log: fix bug #63369 Previous Comments: ------------------------------------------------------------------------ [2012-10-26 12:24:03] tony2001@php.net The following patch has been added/updated: Patch Name: the-patch Revision: 1351254242 URL: https://bugs.php.net/patch-display.php?bug=63369&patch=the-patch&revision=1351254242 ------------------------------------------------------------------------ [2012-10-26 12:23:16] tony2001@php.net Description: ------------ When a fatal error happens in a __sleep/__wakeup function, BG(serialize) and BG(unserialize) contents is left intact and the next request will get those pointers again, even though at that moment they are already freed by Zend memory manager during request shutdown. If you're lucky, there is a chance you'll reuse them, which causes immediate crash. The attached scripts demonstrates the problem with serialize() and I'm kinda lazy to do the same for unserialize(), especially taking into account that the patch is extremely simple. Test script: --------------- class bar1 { function __sleep() { foo(); } } class foo1 { function __sleep() { var_dump(serialize(array("test", "1", 234))); var_dump(serialize(new bar1)); } } $o = new foo1; var_dump(unserialize('O:8:"stdclass":0:{}')); //to clear BG(serialize_lock) var_dump(serialize($o)); Expected result: ---------------- . Actual result: -------------- . ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=63369&edit=1