gnu: imlib2: Fix CVE-2016-4024.

* gnu/packages/patches/imlib2-CVE-2016-4024.patch: New file.
* gnu/local.mk (dist_patch_DATA): Add it.
* gnu/packages/image.scm (imlib2): Use it.

1 files changed, 52 insertions, 0 deletions

diff --git a/gnu/packages/patches/imlib2-CVE-2016-4024.patch b/gnu/packages/patches/imlib2-CVE-2016-4024.patch
new file mode 100644
index 0000000000..c4f1f21b28
--- /dev/null
+++ b/gnu/packages/patches/imlib2-CVE-2016-4024.patch
@@ -0,0 +1,52 @@
+Fix CVE-2016-4024 (integer overflow in lib/image.h).
+
+https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-4024
+
+Upstream source:
+https://git.enlightenment.org/legacy/imlib2.git/commit/?id=7eba2e4c8ac0e20838947f10f29d0efe1add8227
+
+From 7eba2e4c8ac0e20838947f10f29d0efe1add8227 Mon Sep 17 00:00:00 2001
+From: "Yuriy M. Kaminskiy" <yumkam@gmail.com>
+Date: Wed, 6 Apr 2016 03:34:01 +0300
+Subject: Fix integer overflow resulting in insufficient heap allocation
+
+IMAGE_DIMENSIONS_OK ensures that image width and height are less then
+46340, so that maximum number of pixels is ~2**31.
+
+Unfortunately, there are a lot of code that allocates image data with
+something like
+
+   malloc(w * h * sizeof(DATA32));
+
+Obviously, on 32-bit machines this results in integer overflow,
+insufficient heap allocation, with [massive] out-of-bounds heap
+overwrite.
+Either X_MAX should be reduced to 32767, or (w)*(h) should be checked to
+not exceed ULONG_MAX/sizeof(DATA32).
+
+Security implications:
+*) for 32-bit machines: insufficient heap allocation and heap overwrite
+in many image loaders, with escalation potential to remote code
+execution;
+*) for 64-bit machines: it seems, no impact.
+---
+ src/lib/image.h | 3 ++-
+ 1 file changed, 2 insertions(+), 1 deletion(-)
+
+diff --git a/src/lib/image.h b/src/lib/image.h
+index e9eb678..5fae6ed 100644
+--- a/src/lib/image.h
++++ b/src/lib/image.h
+@@ -188,7 +188,8 @@ void                __imlib_SaveImage(ImlibImage * im, const char *file,
+ 
+ /* The maximum pixmap dimension is 65535. */
+ /* However, for now, use 46340 (46340^2 < 2^31) to avoid buffer overflow issues. */
+-#define X_MAX_DIM 46340
++/* Reduced further to 32767, so that (w * h * sizeof(DATA32)) won't exceed ULONG_MAX */
++#define X_MAX_DIM 32767
+ 
+ #define IMAGE_DIMENSIONS_OK(w, h) \
+    ( ((w) > 0) && ((h) > 0) && ((w) < X_MAX_DIM) && ((h) < X_MAX_DIM) )
+-- 
+cgit v0.12
+