Re: [PULL] vhost: cleanups and fixes

[Bijan Mottahedeh]

On 11/30/2018 5:44 AM, Michael S. Tsirkin wrote:
> On Thu, Nov 01, 2018 at 04:06:19PM -0700, Linus Torvalds wrote:
> > On Thu, Nov 1, 2018 at 4:00 PM Kees Cook <keescook@xxxxxxxxxxxx> wrote:
> > > +       memset(&rsp, 0, sizeof(rsp));
> > > +       rsp.response = VIRTIO_SCSI_S_FUNCTION_REJECTED;
> > > +       resp = vq->iov[out].iov_base;
> > > +       ret = __copy_to_user(resp, &rsp, sizeof(rsp));
> > >
> > > Is it actually safe to trust that iov_base has passed an earlier
> > > access_ok() check here? Why not just use copy_to_user() instead?
> > Good point.
> >
> > We really should have removed those double-underscore things ages ago.
> >
> > Also, apart from the address, what about the size? Wouldn't it be
> > better to use copy_to_iter() rather than implement it badly by hand?
> >
> >                 Linus
> Bijan can you respond please?
> Are you going to look into this and convert code to copy_to_iter?
> I don't think we should release Linux like this, so if you don't
> have the time I'd rather revert for now and you can look
> into reposting for the next release.
>
> Thanks,

Sure, will do. Can I send an individual patch for the fix to 
vhost_scsi_send_tmf_reject()?

Thanks.

--bijan