Re: [Qemu-devel] [PATCH] hw/virtio/virtio-balloon: zero-initialize the virtio_balloon_config struct

[Peter Maydell]

On Mon, 21 Jan 2019 at 10:42, Philippe Mathieu-Daudé <address@hidden> wrote:
>
> On 1/18/19 7:36 PM, Peter Maydell wrote:
> > In virtio_balloon_get_config() we initialize a struct virtio_balloon_config
> > which we then copy to guest memory. However, the local variable is not
> > zero initialized. This works OK at the moment because we initialize
> > all the fields in it; however an upcoming kernel header change will
> > add some new fields. If we don't zero out the whole struct then we
> > will start leaking a small amount of the contents of QEMU's stack
> > to the guest as soon as we update linux-headers/ to a set of headers
> > that includes the new fields.
>
> Is it worth Cc'ing address@hidden

Good idea, that will avoid possible future problems if we backport
a headers change to stable.

I'll apply this to master directly.

thanks
-- PMM