Bug #72143 [Csd]: preg_replace uses int instead of size_t on zend_string_allocs

Edit report at https://bugs.php.net/bug.php?id=72143&edit=1 ID: 72143 Updated by: krakjoe@php.net Reported by: burmartke at gmail dot com Summary: preg_replace uses int instead of size_t on zend_string_allocs Status: Closed Type: Bug Package: PCRE related Operating System: Ubuntu 16.04 LTS PHP Version: 7.0.6 -Assigned To: +Assigned To: krakjoe Block user comment: N Private report: N New Comment: Thanks. I didn't add a test, this is an obvious programming error, and it's unreasonable to create tests that allocate that much memory, I think. Previous Comments: ------------------------------------------------------------------------ [2016-05-14 07:21:45] krakjoe@php.net Automatic comment on behalf of krakjoe Revision: http://git.php.net/?p=php-src.git;a=commit;h=fb951553be0175712f4b757e05004110d7421e04 Log: fix #72143 (preg_replace uses int instead of size_t on zend_string_allocs) ------------------------------------------------------------------------ [2016-05-14 07:21:35] krakjoe@php.net Automatic comment on behalf of krakjoe Revision: http://git.php.net/?p=php-src.git;a=commit;h=90f46f2c5bdd3ab0e5dbc3aec1b3294ea1981abe Log: fix #72143 (preg_replace uses int instead of size_t on zend_string_allocs) ------------------------------------------------------------------------ [2016-05-03 12:53:02] burmartke at gmail dot com Description: ------------ preg_replace() declares its alloc_len as an int, and zend_string_(re)alloc() expects a size_t, so when it tries to allocate a string >= 0x40000000 it gets sign-extended and the alloc fails. Test script: --------------- <?php error_log( "++++++++++++++++++++++++++begin " ); $str = str_repeat( 'a', 0x40000000 ) . 'b'; $len = strlen( $str ); error_log( "len=$len (0x" . dechex( $len ) . ")" . ", 18446744071562068000 (0x" . dechex( 18446744071562068000 ) . ")" ); $out = preg_replace( '/b/', '', $str ); error_log( "++++++++++++++++++++++++++end " ); Expected result: ---------------- A successful replace. ++++++++++++++++++++++++++begin len=1073741825 (0x40000001), 18446744071562068000 (0xffffffff80000000) ++++++++++++++++++++++++++end Actual result: -------------- Either a PHP Fatal error: Out of memory (allocated 1075843072) (tried to allocate 18446744071562068000 bytes) or a segmentation fault. ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=72143&edit=1