Bug #54265 [NEW]: crash when variable gets reassigned in error handler

From: stas Operating system: MacOS X 10.6.6 PHP version: 5.3SVN-2011-03-16 (snap) Package: Reproducible crash Bug Type: Bug Bug description:crash when variable gets reassigned in error handler Description: ------------ Reported by Christian Holler on mailing list, the code below produces invalid memory access due to the fact that the line: if (!Z_OBJ_HT_P(object)->write_property) { tries to access handler table of the object variable while it's not an object and is not initialized. Test script: --------------- <?php function my_errorhandler($errno,$errormsg) { global $my_var; $my_var = 0; } set_error_handler("my_errorhandler"); $my_var = str_repeat("A",$my_var[0]->errormsg = "xyz"); Actual result: -------------- ==81019== Invalid read of size 4 ==81019== at 0x563FE7: zend_assign_to_object (in /Users/smalyshev/mphp) ==81019== by 0x563C0A: ZEND_ASSIGN_OBJ_SPEC_VAR_CONST_HANDLER (in /Users/smalyshev/mphp) ==81019== by 0x53AACF: execute (in /Users/smalyshev/mphp) ==81019== by 0x510740: zend_execute_scripts (in /Users/smalyshev/mphp) ==81019== by 0x49D190: php_execute_script (in /Users/smalyshev/mphp) ==81019== by 0x5D2C35: main (in /Users/smalyshev/mphp) ==81019== Address 0x10 is not stack'd, malloc'd or (recently) free'd ==81019== -- Edit bug report at http://bugs.php.net/bug.php?id=54265&edit=1 -- Try a snapshot (PHP 5.2): http://bugs.php.net/fix.php?id=54265&r=trysnapshot52 Try a snapshot (PHP 5.3): http://bugs.php.net/fix.php?id=54265&r=trysnapshot53 Try a snapshot (trunk): http://bugs.php.net/fix.php?id=54265&r=trysnapshottrunk Fixed in SVN: http://bugs.php.net/fix.php?id=54265&r=fixed Fixed in SVN and need be documented: http://bugs.php.net/fix.php?id=54265&r=needdocs Fixed in release: http://bugs.php.net/fix.php?id=54265&r=alreadyfixed Need backtrace: http://bugs.php.net/fix.php?id=54265&r=needtrace Need Reproduce Script: http://bugs.php.net/fix.php?id=54265&r=needscript Try newer version: http://bugs.php.net/fix.php?id=54265&r=oldversion Not developer issue: http://bugs.php.net/fix.php?id=54265&r=support Expected behavior: http://bugs.php.net/fix.php?id=54265&r=notwrong Not enough info: http://bugs.php.net/fix.php?id=54265&r=notenoughinfo Submitted twice: http://bugs.php.net/fix.php?id=54265&r=submittedtwice register_globals: http://bugs.php.net/fix.php?id=54265&r=globals PHP 4 support discontinued: http://bugs.php.net/fix.php?id=54265&r=php4 Daylight Savings: http://bugs.php.net/fix.php?id=54265&r=dst IIS Stability: http://bugs.php.net/fix.php?id=54265&r=isapi Install GNU Sed: http://bugs.php.net/fix.php?id=54265&r=gnused Floating point limitations: http://bugs.php.net/fix.php?id=54265&r=float No Zend Extensions: http://bugs.php.net/fix.php?id=54265&r=nozend MySQL Configuration Error: http://bugs.php.net/fix.php?id=54265&r=mysqlcfg