File u_0002_integer_overflow_in_XF86DRIGetClientDriverName_CVE-2013-1993.patch of Package Mesa.1845

[Mesa-dev] [PATCH:mesa 2/2] integer overflow in XF86DRIGetClientDriverName() [CVE-2013-1993 2/2]
Alan Coopersmith alan.coopersmith at oracle.com

clientDriverNameLength is a CARD32 and needs to be bounds checked before
adding one to it to come up with the total size to allocate, to avoid
integer overflow leading to underallocation and writing data from the
network past the end of the allocated buffer.

Reported-by: Ilja Van Sprundel <ivansprundel at ioactive.com>
Signed-off-by: Alan Coopersmith <alan.coopersmith at oracle.com>
---
 src/glx/XF86dri.c |    8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

Index: mesa-8.0.4/src/glx/XF86dri.c
===================================================================
--- mesa-8.0.4.orig/src/glx/XF86dri.c
+++ mesa-8.0.4/src/glx/XF86dri.c
@@ -300,9 +300,11 @@ XF86DRIGetClientDriverName(Display * dpy
    *ddxDriverPatchVersion = rep.ddxDriverPatchVersion;
 
    if (rep.length) {
-      if (!
-          (*clientDriverName =
-           (char *) Xcalloc(rep.clientDriverNameLength + 1, 1))) {
+      if (rep.clientDriverNameLength < INT_MAX)
+         *clientDriverName = calloc(rep.clientDriverNameLength + 1, 1);
+      else
+         *clientDriverName = NULL;
+      if (*clientDriverName == NULL) {
          _XEatData(dpy, ((rep.clientDriverNameLength + 3) & ~3));
          UnlockDisplay(dpy);
          SyncHandle();