Re: [PATCH] uio_pci_generic does not export memory resources

Hans J. Koch
2012-06-10T19:11:46Z

On Sun, Jun 10, 2012 at 10:00:36PM +0300, Michael S. Tsirkin wrote:
>
> One thing I stand corrected on: assigning a PF that does DMA with VFIO
> *might* be secure, and sometimes, maybe often, is.
> There's just no way to make sure.
> This is unlike uio_pci_generic where it would always be insecure.

You need to be root to access a UIO device, and if you're root, you can
compromise a system in many ways. Before UIO, people used /dev/mem for
similar purposes, and UIO is certainly a seccurity improvement over that.

But of course, UIO presents security risks. Like many other things below
/dev, you need to know what you're doing, and who gets access to /dev/uioX.

Thanks,
Hans