Bug #68986 [Opn->Csd]: pointer returned by php_stream_fopen_temporary_file not validated in memory.c

Edit report at https://bugs.php.net/bug.php?id=68986&edit=1 ID: 68986 Updated by: laruence@php.net Reported by: nayana at ddproperty dot com Summary: pointer returned by php_stream_fopen_temporary_file not validated in memory.c -Status: Open +Status: Closed Type: Bug Package: Streams related Operating System: Linux PHP Version: master-Git-2015-02-05 (Git) -Assigned To: +Assigned To: laruence Block user comment: N Private report: N New Comment: The fix for this bug has been committed. Snapshots of the sources are packaged every three hours; this change will be in the next snapshot. You can grab the snapshot at http://snaps.php.net/. For Windows: http://windows.php.net/snapshots/ Thank you for the report, and for helping us make PHP better. Previous Comments: ------------------------------------------------------------------------ [2015-02-05 04:25:56] nayana at ddproperty dot com Description: ------------ it seems that the pointer returned by php_stream_fopen_temporary_file / php_stream_fopen_tmpfile is not validated prior to use in memory.c in the case where a script is executed in an environment where the TMPDIR is not writable to the user, it will cause a SIGSEGV. from the script side any code that utilize php://temp with 2MB+ buffer with the above condition will encounter this issue. i have fixed the problem on all the calling code in memory.c using php_error_docref, i see that in phar they have handled the condition with zend_throw_exception_ex. i am not in a position to decide which one is best at this time. i think a friendly warning is better than a SIGSEGV at this point :) i have validated this problem exists on github-master and releases 5.4.37, 5.4.17 i will post my pull-request in a comment Test script: --------------- #mkdir /tmp/x #chmod 444 /tmp/x #export TMPDIR=/tmp/x $fp = fopen('php://temp', 'r+'); $data = implode('', array_fill(0, (1024 * 1024 * 2), 'A')); fwrite($fp, $data); ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=68986&edit=1