netdev - Re: [PATCH net-next v3 04/23] net: use zero value to restore rx_buf

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: <CAHS8izPuZRsrBXaQoTNBPyisEo3w7J2aF0qyyOOnUAV=2-8o+w@mail.gmail.com>
Date: Tue, 19 Aug 2025 12:27:27 -0700
From: Mina Almasry <almasrymina@...gle.com>
To: Pavel Begunkov <asml.silence@...il.com>
Cc: Jakub Kicinski <kuba@...nel.org>, netdev@...r.kernel.org, 
	Eric Dumazet <edumazet@...gle.com>, Willem de Bruijn <willemb@...gle.com>, 
	Paolo Abeni <pabeni@...hat.com>, andrew+netdev@...n.ch, horms@...nel.org, 
	davem@...emloft.net, sdf@...ichev.me, dw@...idwei.uk, 
	michael.chan@...adcom.com, dtatulea@...dia.com, ap420073@...il.com, 
	linux-kernel@...r.kernel.org, io-uring@...r.kernel.org
Subject: Re: [PATCH net-next v3 04/23] net: use zero value to restore
 rx_buf_len to default

On Tue, Aug 19, 2025 at 8:51 AM Pavel Begunkov <asml.silence@...il.com> wrote:
>
> On 8/19/25 01:07, Mina Almasry wrote:
> > On Mon, Aug 18, 2025 at 6:56 AM Pavel Begunkov <asml.silence@...il.com> wrote:
> >>
> >> From: Jakub Kicinski <kuba@...nel.org>
> >>
> >> Distinguish between rx_buf_len being driver default vs user config.
> >> Use 0 as a special value meaning "unset" or "restore driver default".
> >> This will be necessary later on to configure it per-queue, but
> >> the ability to restore defaults may be useful in itself.
> >>
> >> Signed-off-by: Jakub Kicinski <kuba@...nel.org>
> >> Signed-off-by: Pavel Begunkov <asml.silence@...il.com>
> >
> > I wonder if it should be extended to the other driver using
> > rx_buf_len, hns3. For that, I think the default buf size would be
> > HNS3_DEFAULT_RX_BUF_LEN.
>
> I'd rather avoid growing the series even more, let's follow up on
> that in a separate patch on top, that should be just fine. And
> thanks for the review
>
> > Other than that, seems fine to me,
> >
> > Reviewed-by: Mina Almasry <almasrymina@...gle.com>
>
> With the said above, do you want me to retain the review tag?
>

I initially thought adding my reviewed-by would be fine, but on closer
look, doesn't this series break rx_buf_len setting for hns3? AFAICT so
far, in patch 3 you're adding a check to ethnl_set_rings where it'll
be an error if rx_buf_len > rx_buf_len_max, and i'm guessing if the
driver never sets rx_buf_len_max it'll be 0 initialized and that check
would always fail? Or did I miss something?

-- 
Thanks,
Mina