gnu: libxfont: Fix CVE-2017-13720, CVE-2017-13722.

* gnu/packages/patches/libxfont-CVE-2017-13720.patch,
  gnu/packages/patches/libxfont-CVE-2017-13722.patch: New files.
* gnu/local.mk (dist_patch_DATA): Register them.
* gnu/packages/xorg.scm (libxfont, libxfont2)[source]: Use them.

1 files changed, 53 insertions, 0 deletions

diff --git a/gnu/packages/patches/libxfont-CVE-2017-13722.patch b/gnu/packages/patches/libxfont-CVE-2017-13722.patch
new file mode 100644
index 0000000000..458fdfd1a7
--- /dev/null
+++ b/gnu/packages/patches/libxfont-CVE-2017-13722.patch
@@ -0,0 +1,53 @@
+Fix CVE-2017-13722.
+
+Copied from upstream source repository:
+<https://cgit.freedesktop.org/xorg/lib/libXfont/commit/?id=672bb944311392e2415b39c0d63b1e1902905bcd>
+
+From 672bb944311392e2415b39c0d63b1e1902905bcd Mon Sep 17 00:00:00 2001
+From: Michal Srb <msrb@suse.com>
+Date: Thu, 20 Jul 2017 17:05:23 +0200
+Subject: pcfGetProperties: Check string boundaries (CVE-2017-13722)
+
+Without the checks a malformed PCF file can cause the library to make
+atom from random heap memory that was behind the `strings` buffer.
+This may crash the process or leak information.
+
+Signed-off-by: Julien Cristau <jcristau@debian.org>
+
+diff --git a/src/bitmap/pcfread.c b/src/bitmap/pcfread.c
+index dab1c44..ae34c28 100644
+--- a/src/bitmap/pcfread.c
++++ b/src/bitmap/pcfread.c
+@@ -45,6 +45,7 @@ from The Open Group.
+ 
+ #include <stdarg.h>
+ #include <stdint.h>
++#include <string.h>
+ 
+ void
+ pcfError(const char* message, ...)
+@@ -311,11 +312,19 @@ pcfGetProperties(FontInfoPtr pFontInfo, FontFilePtr file,
+     if (IS_EOF(file)) goto Bail;
+     position += string_size;
+     for (i = 0; i < nprops; i++) {
++	if (props[i].name >= string_size) {
++	    pcfError("pcfGetProperties(): String starts out of bounds (%ld/%d)\n", props[i].name, string_size);
++	    goto Bail;
++	}
+ 	props[i].name = MakeAtom(strings + props[i].name,
+-				 strlen(strings + props[i].name), TRUE);
++				 strnlen(strings + props[i].name, string_size - props[i].name), TRUE);
+ 	if (isStringProp[i]) {
++	    if (props[i].value >= string_size) {
++		pcfError("pcfGetProperties(): String starts out of bounds (%ld/%d)\n", props[i].value, string_size);
++		goto Bail;
++	    }
+ 	    props[i].value = MakeAtom(strings + props[i].value,
+-				      strlen(strings + props[i].value), TRUE);
++				      strnlen(strings + props[i].value, string_size - props[i].value), TRUE);
+ 	}
+     }
+     free(strings);
+-- 
+cgit v0.10.2
+