ID: 34704 Updated by: [EMAIL PROTECTED] Reported By: t dot starling at physics dot unimelb dot edu dot au -Status: Assigned +Status: Closed Bug Type: EXIF related Operating System: * PHP Version: 5CVS, 6CVS, 4CVS (2005-10-02) Assigned To: helly 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. Fixed for 4.4.1, 5.0.6, 5.1.0, HEAD Previous Comments: ------------------------------------------------------------------------ [2005-10-02 22:13:31] [EMAIL PROTECTED] Assigned to the "maintainer". ------------------------------------------------------------------------ [2005-10-02 21:33:13] t dot starling at physics dot unimelb dot edu dot au There are no significant changes between 4.4.0 and HEAD, you should be able to forward-port it without any trouble. See http://cvs.php.net/diff.php/php-src/ext/exif/exif.c?r1=1.173&r2=1.118.2.37.2.1&ty=h My patch comes in at around line 3039, as you can see there are only documentation changes. This patch is now in production on wikipedia.org and related websites. I for one don't want to see my website get DoSed because of this. ------------------------------------------------------------------------ [2005-10-02 13:05:29] [EMAIL PROTECTED] Please try using this CVS snapshot: http://snaps.php.net/php5-latest.tar.gz For Windows: http://snaps.php.net/win32/php5-win32-latest.zip ------------------------------------------------------------------------ [2005-10-02 09:07:14] t dot starling at physics dot unimelb dot edu dot au Description: ------------ An image, seen in the wild and probably generated non-maliciously, reliably causes exif_read_data() to go into infinite recursion. I've fixed the problem and created a patch against PHP 4.4.0: http://wikimedia.org/~tstarling/php/exif_IFD2.patch The test image is here: http://wikimedia.org/~tstarling/php/Carcraftbuckett.jpg The problem was an assumption that images would follow the spec and include a maximum of 2 IFD headers, IFD0 for the image and IFD1 for the thumbnail. The test image probably has the "next IFD offset" field pointing back to the same structure, creating an infinite loop. I haven't studied the test image in detail, but my patch allows PHP's Exif functions to read it without segfaulting, which is good enough for me. I decided to ignore any further IFDs beyond the first two rather than issue an error, for compatibility with possible future revisions of the Exif spec. -- Tim Starling (MediaWiki developer) ------------------------------------------------------------------------ -- Edit this bug report at http://bugs.php.net/?id=34704&edit=1