kumquat-buildroot/package/cairo/0004-Fix-mask-usage-in-image-compositor.patch
Quentin Schulz 111ab56d84 package/cairo: fix CVE-2020-35492
Add an upstream patch to fix CVE-2020-35492:
A flaw was found in cairo's image-compositor.c in all versions prior to
1.17.4. This flaw allows an attacker who can provide a crafted input
file to cairo's image-compositor (for example, by convincing a user to
open a file in an application using cairo, or if an application uses
cairo on untrusted input) to cause a stack buffer overflow ->
out-of-bounds WRITE. The highest impact from this vulnerability is to
confidentiality, integrity, as well as system availability.

Important note: this is not the exact upstream patch. Indeed, the
upstream patch[1] contains a png file which appears as a binary diff
inside the patch. The `patch` tool which is used by Buildroot to apply
patches does not handle that kind of diff. Since it is just a test, it
shouldn't impact the quality of the CVE fix and all changes related to
the test are removed from the patch.

[1] 03a820b173
Cc: Quentin Schulz <foss+buildroot@0leil.net>
Signed-off-by: Quentin Schulz <quentin.schulz@theobroma-systems.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
2022-12-14 20:02:45 +01:00

57 lines
1.7 KiB
Diff

From 03a820b173ed1fdef6ff14b4468f5dbc02ff59be Mon Sep 17 00:00:00 2001
From: Heiko Lewin <heiko.lewin@worldiety.de>
Date: Tue, 15 Dec 2020 16:48:19 +0100
Subject: [PATCH] Fix mask usage in image-compositor
[Retrieved from
https://gitlab.freedesktop.org/cairo/cairo/-/commit/03a820b173ed1fdef6ff14b4468f5dbc02ff59be]
[Removed changes in test/ directory to remove binary diff so that the
patch can be applied by `patch` tool]
Signed-off-by: Quentin Schulz <quentin.schulz@theobroma-systems.com>
---
src/cairo-image-compositor.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/src/cairo-image-compositor.c b/src/cairo-image-compositor.c
index bbf4cf228..2352c478e 100644
--- a/src/cairo-image-compositor.c
+++ b/src/cairo-image-compositor.c
@@ -2601,14 +2601,14 @@ _inplace_src_spans (void *abstract_renderer, int y, int h,
unsigned num_spans)
{
cairo_image_span_renderer_t *r = abstract_renderer;
- uint8_t *m;
+ uint8_t *m, *base = (uint8_t*)pixman_image_get_data(r->mask);
int x0;
if (num_spans == 0)
return CAIRO_STATUS_SUCCESS;
x0 = spans[0].x;
- m = r->_buf;
+ m = base;
do {
int len = spans[1].x - spans[0].x;
if (len >= r->u.composite.run_length && spans[0].coverage == 0xff) {
@@ -2646,7 +2646,7 @@ _inplace_src_spans (void *abstract_renderer, int y, int h,
spans[0].x, y,
spans[1].x - spans[0].x, h);
- m = r->_buf;
+ m = base;
x0 = spans[1].x;
} else if (spans[0].coverage == 0x0) {
if (spans[0].x != x0) {
@@ -2675,7 +2675,7 @@ _inplace_src_spans (void *abstract_renderer, int y, int h,
#endif
}
- m = r->_buf;
+ m = base;
x0 = spans[1].x;
} else {
*m++ = spans[0].coverage;
--
2.38.1