Bug 1306681 (CVE-2013-7447)

Summary:	CVE-2013-7447 gtk2, gtk3: Integer overflow in image handling
Product:	[Other] Security Response	Reporter:	Adam Mariš <amaris>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED WONTFIX	QA Contact:
Severity:	low	Docs Contact:
Priority:	low
Version:	unspecified	CC:	anemec, ccecchi, mclasen, otte, slawomir
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2016-03-14 06:21:57 UTC	Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:	1306682, 1306683
Bug Blocks:	1306685

Description Adam Mariš 2016-02-11 15:04:25 UTC

An integer overflow vulnerability in gtk+2.0 and gtk+3.0 in image handling was found when supplying large pixbufs to gdk_cairo_set_source_pixbuf, gdkcairo tries to allocate an immense number of bytes.

Upstream patch:

https://git.gnome.org/browse/gtk+/commit?id=894b1ae76a32720f4bb3d39cf460402e3ce331d6

CVE request:

http://seclists.org/oss-sec/2016/q1/302

Comment 1 Adam Mariš 2016-02-11 15:06:42 UTC

Created gtk2 tracking bugs for this issue:

Affects: fedora-all [bug 1306682]

Comment 2 Adam Mariš 2016-02-11 15:06:47 UTC

Created gtk3 tracking bugs for this issue:

Affects: fedora-all [bug 1306683]

Comment 3 Huzaifa S. Sidhpurwala 2016-03-14 06:08:00 UTC

This is basically a DoS flaw when opening a crafted image. When g_malloc() is asked to malloc huge amount of memory, and it is unable to do it, it crashes with a g_error() amount similar to:

(eog:18754): GLib-ERROR **: /build/buildd/glib2.0-2.36.0/./glib/gmem.c:165: failed to allocate 18446744071914584320 bytes

Also it looks like gtk3 is not affected by this flaw, since the code there is completely different. 

In gdk_cairo_set_source_pixbuf() rather than doing:

cairo_pixels = g_malloc (height * cairo_stride); and creating a "surface" after that by using cairo_image_surface_create_for_data() what gtk3 does is that it uses the cairo function cairo_surface_create_similar_image() to create the surface.

cairo_surface_create_similar_image() uses pixman_image_create() which calculates the size of the buffer needed to hold the image. 

pixman_image_create() handles it correctly by using the following code:

 pixels = FbPixelsCreate (width, height, format->depth);
     if (pixels == NULL)
 	return NULL;