Re: [RFC PATCH v2 2/3] virtio/vsock: WARN_ONCE() for invalid state of socket

[Stefano Garzarella]

On Tue, Mar 28, 2023 at 11:35 AM Arseniy Krasnov
<avkrasnov@xxxxxxxxxxxxxx> wrote:
>
>
>
> On 28.03.2023 12:29, Stefano Garzarella wrote:
> > On Sun, Mar 26, 2023 at 01:09:25AM +0300, Arseniy Krasnov wrote:
> >> This adds WARN_ONCE() and return from stream dequeue callback when
> >> socket's queue is empty, but 'rx_bytes' still non-zero.
> >
> > Nit: I would explain why we add this, for example:
> >
> > This allows the detection of potential bugs due to packet merging
> > (see previous patch).
> >
> >>
> >> Signed-off-by: Arseniy Krasnov <AVKrasnov@xxxxxxxxxxxxxx>
> >> ---
> >> net/vmw_vsock/virtio_transport_common.c | 7 +++++++
> >> 1 file changed, 7 insertions(+)
> >
> >>
> >> diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c
> >> index b9144af71553..ad70531de133 100644
> >> --- a/net/vmw_vsock/virtio_transport_common.c
> >> +++ b/net/vmw_vsock/virtio_transport_common.c
> >> @@ -398,6 +398,13 @@ virtio_transport_stream_do_dequeue(struct vsock_sock *vsk,
> >>     u32 free_space;
> >>
> >>     spin_lock_bh(&vvs->rx_lock);
> >> +
> >> +    if (WARN_ONCE(skb_queue_empty(&vvs->rx_queue) && vvs->rx_bytes,
> >> +              "No skbuffs with non-zero 'rx_bytes'\n")) {
> >
> > Nit: I would rephrase it this way:
> > "rx_queue is empty, but rx_bytes is non-zero"
> >
> >> +        spin_unlock_bh(&vvs->rx_lock);
> >> +        return err;
> >> +    }
> >> +
> >>     while (total < len && !skb_queue_empty(&vvs->rx_queue)) {
> >>         skb = skb_peek(&vvs->rx_queue);
> >>
> >> --
> >> 2.25.1
> >>
> >
> > Anyway the patch LGTM!
>
> Thanks for review! Since only string value and commit message should be
> updated, i can resend it with 'net' (as it is fix) and update two thing
> above in 'net' version?

Yep, sure!

And you can already add my R-b ;-)

Thanks,
Stefano

>
> Thanks, Arseniy
> >
> > Reviewed-by: Stefano Garzarella <sgarzare@xxxxxxxxxx>
> >
>