vmsvga: shadow fifo registers
commit71798fda8b6ef8df47c7640ba0bc24d7060ad307
authorGerd Hoffmann <kraxel@redhat.com>
Mon, 30 May 2016 07:09:20 +0000 (30 09:09 +0200)
committerMichael Roth <mdroth@linux.vnet.ibm.com>
Fri, 5 Aug 2016 18:37:40 +0000 (5 13:37 -0500)
tree1668041a8904c476ac098f13d701158810831cb3
parent3141be668fa508f08d76de576c381692bccd99ad
vmsvga: shadow fifo registers

The fifo is normal ram.  So kvm vcpu threads and qemu iothread can
access the fifo in parallel without syncronization.  Which in turn
implies we can't use the fifo pointers in-place because the guest
can try changing them underneath us.  So add shadows for them, to
make sure the guest can't modify them after we've applied sanity
checks.

Fixes: CVE-2016-4454
Cc: qemu-stable@nongnu.org
Cc: P J P <ppandit@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Message-id: 1464592161-18348-4-git-send-email-kraxel@redhat.com
(cherry picked from commit 7e486f7577764a07aa35588e119903c80a5c30a2)
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
hw/display/vmware_vga.c