gnu: gd: Fix CVE-2016-7568.

* gnu/packages/patches/gd-CVE-2016-7568.patch: New file.
* gnu/local.mk (dist_patch_DATA): Add it.
* gnu/packages/gd.scm (gd)[source]: Use it.

gnu/local.mk

@@ -529,6 +529,7 @@ dist_patch_DATA =						\
   %D%/packages/patches/gcc-cross-environment-variables.patch	\
   %D%/packages/patches/gcc-libvtv-runpath.patch			\
   %D%/packages/patches/gcc-5.0-libvtv-runpath.patch		\
+  %D%/packages/patches/gd-CVE-2016-7568.patch			\
   %D%/packages/patches/gd-fix-gd2-read-test.patch		\
   %D%/packages/patches/gd-fix-tests-on-i686.patch		\
   %D%/packages/patches/gegl-CVE-2012-4433.patch			\

gnu/packages/gd.scm

@@ -50,7 +50,8 @@
              (sha256
               (base32
                "0g3xz8jpz1pl2zzmssglrpa9nxiaa7rmcmvgpbrjz8k9cyynqsvl"))
-             (patches (search-patches "gd-fix-gd2-read-test.patch"
+             (patches (search-patches "gd-CVE-2016-7568.patch"
+                                      "gd-fix-gd2-read-test.patch"
                                       "gd-fix-tests-on-i686.patch"))))
     (build-system gnu-build-system)
     (native-inputs

gnu/packages/patches/gd-CVE-2016-7568.patch

@@ -0,0 +1,44 @@
+Fix CVE-2016-7568 (integer overflow in gdImageWebpCtx()):
+
+https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-7568
+
+Patch copied from upstream source repository:
+
+https://github.com/libgd/libgd/commit/2806adfdc27a94d333199345394d7c302952b95f
+
+From 2806adfdc27a94d333199345394d7c302952b95f Mon Sep 17 00:00:00 2001
+From: trylab <trylab@users.noreply.github.com>
+Date: Tue, 6 Sep 2016 18:35:32 +0800
+Subject: [PATCH] Fix integer overflow in gdImageWebpCtx
+
+Integer overflow can be happened in expression gdImageSX(im) * 4 *
+gdImageSY(im). It could lead to heap buffer overflow in the following
+code. This issue has been reported to the PHP Bug Tracking System. The
+proof-of-concept file will be supplied some days later. This issue was
+discovered by Ke Liu of Tencent's Xuanwu LAB.
+---
+ src/gd_webp.c | 8 ++++++++
+ 1 file changed, 8 insertions(+)
+
+diff --git a/src/gd_webp.c b/src/gd_webp.c
+index 8eb4dee..9886399 100644
+--- a/src/gd_webp.c
++++ b/src/gd_webp.c
+@@ -199,6 +199,14 @@ BGD_DECLARE(void) gdImageWebpCtx (gdImagePtr im, gdIOCtx * outfile, int quality)
+ 		quality = 80;
+ 	}
+ 
++	if (overflow2(gdImageSX(im), 4)) {
++		return;
++	}
++
++	if (overflow2(gdImageSX(im) * 4, gdImageSY(im))) {
++		return;
++	}
++
+ 	argb = (uint8_t *)gdMalloc(gdImageSX(im) * 4 * gdImageSY(im));
+ 	if (!argb) {
+ 		return;
+-- 
+2.10.0
+