Re: [PATCH bpf-next v2 0/6] selftests/bpf: Various sockmap-related fixes

From: Michal Luczaj
Date: Wed Oct 02 2024 - 04:28:18 EST


On 9/27/24 11:15, Jakub Sitnicki wrote:
> On Fri, Sep 27, 2024 at 12:54 AM +02, Michal Luczaj wrote:
>> ...
>> Here's a follow up: my guess is that some checks are missing. I'm not sure
>> if it's the best approach, but this fixes things for me:
>
> So you have already found a bug with a negative test. Nice.
>
> Your patch makes sense to me.

Great, I'll submit it properly.

Another thing I've noticed is that unsupported (non-TCP) sk_msg redirects
fail silently, i.e. send() is successful, then packet appears to be
dropped, but because the BPF_SK_MSG_VERDICT program is never run, the
verdict[SK_DROP] isn't updated. Is this by design?

Also, for unsupported af_vsock sk_skb-to-ingress we hit the warning:

[ 233.396654] rx_queue is empty, but rx_bytes is non-zero
[ 233.396702] WARNING: CPU: 11 PID: 40601 at net/vmw_vsock/virtio_transport_common.c:589 virtio_transport_stream_dequeue+0x2e5/0x2f0

I'll try to fix that. Now, the series begin to grow long. Should the fixes
come separately?

> FYI, I've started a GH repo for anciallary materials for sockmap.
> Code samples, pointers to resources, a backlog of stuff to do (?).
> Inspired by the xdp-project repo:
>
> https://github.com/xdp-project/xdp-project
>
> We can move it to a dedicated project namespace, right now it's at:
>
> https://github.com/jsitnicki/sockmap-project/
>
> Feel free to add stuff there.

Not that I have anything to add, but sure, thanks :)

Michal