Re: [Qemu-devel] Re: [PATCHv2 09/12] vhost: vhost net support

[Paul Brook]

> > I'm pretty sure a guest can cause those to change and I'm not 100%
> > sure,   but I think it's a potential source of exploits if you assume a
> > mapping. In the very least, a guest can trick vhost into writing to ram
> > that it wouldn't normally write to.
> 
> This seems harmless. guest can write anywhere in ram, anyway.

Surely writing to the wrong address is always a fatal flaw.  There certainly 
exist machines that can change physical RAM mapping.  While I wouldn't expect 
this to happen during normal operation, it could occur between a (virtio-
aware) bootloader/BIOS and real kernel.

Paul