shm: Fix xselinux resource initialization for xinerama pixmaps

This is necessary to avoid a NULL pointer deference when the pixmap is
used later.

[ajax: massaged commit message, fixed it to compile]

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=89748
Reviewed-by: Adam Jackson <ajax@redhat.com>
Signed-off-by: Brent Collins <bcollins@trustedcs.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/Xext/shm.c b/Xext/shm.c
index 52d997425..b359a9035 100644
--- a/Xext/shm.c
+++ b/Xext/shm.c
@@ -971,6 +971,12 @@ ProcPanoramiXShmCreatePixmap(ClientPtr client)
                                                        stuff->offset);
 
         if (pMap) {
+            result = XaceHook(XACE_RESOURCE_ACCESS, client, stuff->pid,
+                              RT_PIXMAP, pMap, RT_NONE, NULL, DixCreateAccess);
+            if (result != Success) {
+                pDraw->pScreen->DestroyPixmap(pMap);
+                return result;
+            }
             dixSetPrivate(&pMap->devPrivates, shmPixmapPrivateKey, shmdesc);
             shmdesc->refcnt++;
             pMap->drawable.serialNumber = NEXT_SERIAL_NUMBER;