netdev - Re: [PATCH 1/1] RDMA/rxe: Fetch skb packets from ethernet layer

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <CAD=hENcAc8TZSeW1ba_BDiT7M7+HeyWUHSVwnFQjOi6vk5TPMQ@mail.gmail.com>
Date:   Tue, 10 Nov 2020 09:58:24 +0800
From:   Zhu Yanjun <zyjzyj2000@...il.com>
To:     Jakub Kicinski <kuba@...nel.org>
Cc:     Doug Ledford <dledford@...hat.com>, Jason Gunthorpe <jgg@...pe.ca>,
        linux-rdma@...r.kernel.org, netdev <netdev@...r.kernel.org>
Subject: Re: [PATCH 1/1] RDMA/rxe: Fetch skb packets from ethernet layer

On Tue, Nov 10, 2020 at 2:25 AM Jakub Kicinski <kuba@...nel.org> wrote:
>
> On Sun, 8 Nov 2020 13:27:32 +0800 Zhu Yanjun wrote:
> > On Sun, Nov 8, 2020 at 1:24 PM Zhu Yanjun <zyjzyj2000@...il.com> wrote:
> > > On Thu, 5 Nov 2020 19:12:01 +0800 Zhu Yanjun wrote:
> > >
> > > In the original design, in rx, skb packet would pass ethernet
> > > layer and IP layer, eventually reach udp tunnel.
> > >
> > > Now rxe fetches the skb packets from the ethernet layer directly.
> > > So this bypasses the IP and UDP layer. As such, the skb packets
> > > are sent to the upper protocals directly from the ethernet layer.
> > >
> > > This increases bandwidth and decreases latency.
> > >
> > > Signed-off-by: Zhu Yanjun <yanjunz@...dia.com>
> > >
> > >
> > > Nope, no stealing UDP packets with some random rx handlers.
> >
> > Why? Is there any risks?
>
> Are there risks in layering violations? Yes.
>
> For example - you do absolutely no protocol parsing,

Protocol parsing is in rxe driver.

> checksum validation, only support IPv4, etc.

Since only ipv4 is supported in rxe, if ipv6 is supported in rxe, I
will add ipv6.

>
> Besides it also makes the code far less maintainable, rx_handler is a

This rx_handler is also used in openvswitch and bridge.

Zhu Yanjun

> singleton, etc. etc.
>
> > > The tunnel socket is a correct approach.