#46147 [Asn->Csd]: after stream seek, appending stream filter reads incorrect data

ID: 46147 Updated by: cellog@php.net Reported By: cellog@php.net -Status: Assigned +Status: Closed Bug Type: Streams related Operating System: n/a PHP Version: 5.3CVS-2008-09-22 (CVS) Assigned To: cellog New Comment: This bug has been fixed in CVS. 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/. Thank you for the report, and for helping us make PHP better. Previous Comments: ------------------------------------------------------------------------ [2008-09-22 01:23:21] cellog@php.net Description: ------------ appending a stream filter to a stream that has already had data read into its buffer can cause unfiltered data to be read back in. This is because the data is written to writepos, but read from readpos, and so the buffer should be invalidated (writepos/readpos set to 0) prior to writing back the filtered data. This bug affects all PHP versions, and will be fixed in 5.2, 5.3, and 6.0 by me, I have a working patch ready to commit momentarily This bug was causing ext/phar/tests/zip/badalias.phpt to fail Reproduce code: --------------- execute within php5/ext/phar/tests/zip: <?php $a = fopen(dirname(__FILE__) . '/files/' . "badalias1.phar.zip", 'rb'); fseek($a, 37); // seek to zip header $b = fread($a, 30); fseek($a, 82); // seek to file data stream_filter_append($a, 'zlib.inflate', STREAM_FILTER_READ); var_dump(fread($a, 8)); ?> Expected result: ---------------- string(8) "hi/there" Actual result: -------------- string(8) "&#65533;&#65533;&#65533;/&#65533;H-J" ------------------------------------------------------------------------ -- Edit this bug report at http://bugs.php.net/?id=46147&edit=1