Subject: CVS commit: pkgsrc/x11
From: Maya Rashish
Date: 2020-07-31 18:50:57
Message id: 20200731165057.A4F86FB28@cvs.NetBSD.org

Log Message:
modular-xorg-*: provide patch (making this package equivalent to
xorg-server 1.20.9, couldn't find a tarball).

X.Org security advisory: July 31, 2020

X Server Pixel Data Uninitialized Memory Information Disclosure
===============================================================

CVE-2020-14347

Allocation for pixmap data in AllocatePixmap() does not initialize the
memory in xserver, it leads to leak uninitialize heap memory to
clients. When the X server runs with elevated privileges.

This flaw can lead to ASLR bypass, which when combined with other
flaws (known/unknown) could lead to lead to privilege elevation in the
client.

Patch
=====

A patch for this issue has been commited to the xorg server git
repository.  xorg-server 1.20.9 will be released shortly and will
include this patch.

https://gitlab.freedesktop.org/xorg/xserver.git

diff --git a/dix/pixmap.c b/dix/pixmap.c
index 1186d7dbb..5a0146bbb 100644
--- a/dix/pixmap.c
+++ b/dix/pixmap.c
@@ -116,7 +116,7 @@ AllocatePixmap(ScreenPtr pScreen, int pixDataSize)
     if (pScreen->totalPixmapSize > ((size_t) - 1) - pixDataSize)
         return NullPixmap;

-    pPixmap = malloc(pScreen->totalPixmapSize + pixDataSize);
+    pPixmap = calloc(1, pScreen->totalPixmapSize + pixDataSize);
     if (!pPixmap)
         return NullPixmap;

Thanks
======

This vulnerability was discovered by Jan-Niklas Sohn working with
Trend Micro Zero Day Initiative.

Files:
RevisionActionfile
1.1addpkgsrc/x11/modular-xorg-server/patches/patch-dix_pixmap.c
1.8modifypkgsrc/x11/modular-xorg-xwayland/Makefile
1.20modifypkgsrc/x11/modular-xorg-xephyr/Makefile
1.102modifypkgsrc/x11/modular-xorg-server/distinfo
1.128modifypkgsrc/x11/modular-xorg-server/Makefile