Re: [PATCH v8 3/3] hv_netvsc: Use vmbus_requestor to generate transaction IDs for VMBus hardening

From: Andrea Parri
Date: Wed Nov 04 2020 - 22:33:16 EST


On Wed, Nov 04, 2020 at 01:45:05PM -0800, Jakub Kicinski wrote:
> On Wed, 4 Nov 2020 13:43:48 -0800 Jakub Kicinski wrote:
> > On Wed, 4 Nov 2020 16:40:27 +0100 Andrea Parri (Microsoft) wrote:
> > > From: Andres Beltran <lkmlabelt@xxxxxxxxx>
> > >
> > > Currently, pointers to guest memory are passed to Hyper-V as
> > > transaction IDs in netvsc. In the face of errors or malicious
> > > behavior in Hyper-V, netvsc should not expose or trust the transaction
> > > IDs returned by Hyper-V to be valid guest memory addresses. Instead,
> > > use small integers generated by vmbus_requestor as requests
> > > (transaction) IDs.
> > >
> > > Signed-off-by: Andres Beltran <lkmlabelt@xxxxxxxxx>
> > > Co-developed-by: Andrea Parri (Microsoft) <parri.andrea@xxxxxxxxx>
> > > Signed-off-by: Andrea Parri (Microsoft) <parri.andrea@xxxxxxxxx>
> > > Reviewed-by: Michael Kelley <mikelley@xxxxxxxxxxxxx>
> >
> > I'm assuming this is targeting net-next? If so could you please tag it
> > as [PATCH net-next vN]?
>
> Ah, you don't 'cause you only sent us the third patch. In that case with
> the nit below addressed:
>
> Acked-by: Jakub Kicinski <kuba@xxxxxxxxxx>

I fixed the declarations locally. Thank you for the review, Jakub.

(Yes, FWIW, I was imaging the series to go via hyperv-next...)

Thanks,
Andrea


>
> > > @@ -695,10 +695,19 @@ static void netvsc_send_tx_complete(struct net_device *ndev,
> > > const struct vmpacket_descriptor *desc,
> > > int budget)
> > > {
> > > - struct sk_buff *skb = (struct sk_buff *)(unsigned long)desc->trans_id;
> > > + struct sk_buff *skb;
> > > struct net_device_context *ndev_ctx = netdev_priv(ndev);
> >
> > Swap these two lines please to keep the variables declaration lines
> > longest to shortest.
>