From: Søren Sandmann <ssp@redhat.com>
Date: Wed, 9 Apr 2014 18:14:12 +0000 (-0400)
Subject: create_bits(): Cast the result of height * stride to size_t
X-Git-Tag: pixman-0.33.2~61
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=857e40f3d2bc2cfb714913e0cd7e6184cf69aca3;p=platform%2Fupstream%2Fpixman.git

create_bits(): Cast the result of height * stride to size_t

In create_bits() both height and stride are ints, so the result is
also an int, which will overflow if height or stride are big enough
and size_t is bigger than int.

This patch simply casts height to size_t to prevent these overflows,
which prevents the crash in:

    https://bugzilla.redhat.com/show_bug.cgi?id=972647

It's not even close to fixing the full problem of supporting big
images in pixman.

See also

    https://bugs.freedesktop.org/show_bug.cgi?id=69014
---

diff --git a/pixman/pixman-bits-image.c b/pixman/pixman-bits-image.c
index f9121a3..dcdcc69 100644
--- a/pixman/pixman-bits-image.c
+++ b/pixman/pixman-bits-image.c
@@ -926,7 +926,7 @@ create_bits (pixman_format_code_t format,
     if (_pixman_multiply_overflows_size (height, stride))
 	return NULL;
 
-    buf_size = height * stride;
+    buf_size = (size_t)height * stride;
 
     if (rowstride_bytes)
 	*rowstride_bytes = stride;