vhost: Fix Spectre V1 vulnerability
The idx in vhost_vring_ioctl() was controlled by userspace, hence a
potential exploitation of the Spectre variant 1 vulnerability.
Fixing this by sanitizing idx before using it to index d->vqs.
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
CVE-2017-5753
(cherry picked from commit
ff002269a4ee9c769dbf9365acef633ebcbd6cbe)
Signed-off-by: Juerg Haefliger <juergh@canonical.com>
Acked-by: Stefan Bader <stefan.bader@canonical.com>
Acked-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>