netdev - Re: [PATCH net-next v3 5/7] net: devmem: add ring parameter filtering

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: <CAMArcTX+j4patttqm+F8zLAE55DDn1mpBuXQoWpf3NCHo96cYw@mail.gmail.com>
Date: Fri, 4 Oct 2024 13:01:17 +0900
From: Taehee Yoo <ap420073@...il.com>
To: Brett Creeley <bcreeley@....com>
Cc: davem@...emloft.net, kuba@...nel.org, pabeni@...hat.com, 
	edumazet@...gle.com, almasrymina@...gle.com, netdev@...r.kernel.org, 
	linux-doc@...r.kernel.org, donald.hunter@...il.com, corbet@....net, 
	michael.chan@...adcom.com, kory.maincent@...tlin.com, andrew@...n.ch, 
	maxime.chevallier@...tlin.com, danieller@...dia.com, hengqi@...ux.alibaba.com, 
	ecree.xilinx@...il.com, przemyslaw.kitszel@...el.com, hkallweit1@...il.com, 
	ahmed.zaki@...el.com, paul.greenwalt@...el.com, rrameshbabu@...dia.com, 
	idosch@...dia.com, asml.silence@...il.com, kaiyuanz@...gle.com, 
	willemb@...gle.com, aleksander.lobakin@...el.com, dw@...idwei.uk, 
	sridhar.samudrala@...el.com
Subject: Re: [PATCH net-next v3 5/7] net: devmem: add ring parameter filtering

On Fri, Oct 4, 2024 at 3:35 AM Brett Creeley <bcreeley@....com> wrote:
>

Hi Brett,
Thanks a lot for your review!

>
>
> On 10/3/2024 9:06 AM, Taehee Yoo wrote:
> > Caution: This message originated from an External Source. Use proper caution when opening attachments, clicking links, or responding.
> >
> >
> > If driver doesn't support ring parameter or tcp-data-split configuration
> > is not sufficient, the devmem should not be set up.
> > Before setup the devmem, tcp-data-split should be ON and
> > tcp-data-split-thresh value should be 0.
> >
> > Signed-off-by: Taehee Yoo <ap420073@...il.com>
> > ---
> >
> > v3:
> >   - Patch added.
> >
> >   net/core/devmem.c | 18 ++++++++++++++++++
> >   1 file changed, 18 insertions(+)
> >
> > diff --git a/net/core/devmem.c b/net/core/devmem.c
> > index 11b91c12ee11..a9e9b15028e0 100644
> > --- a/net/core/devmem.c
> > +++ b/net/core/devmem.c
> > @@ -8,6 +8,8 @@
> >    */
> >
> >   #include <linux/dma-buf.h>
> > +#include <linux/ethtool.h>
> > +#include <linux/ethtool_netlink.h>
> >   #include <linux/genalloc.h>
> >   #include <linux/mm.h>
> >   #include <linux/netdevice.h>
> > @@ -131,6 +133,8 @@ int net_devmem_bind_dmabuf_to_queue(struct net_device *dev, u32 rxq_idx,
> >                                      struct net_devmem_dmabuf_binding *binding,
> >                                      struct netlink_ext_ack *extack)
> >   {
> > +       struct kernel_ethtool_ringparam kernel_ringparam = {};
> > +       struct ethtool_ringparam ringparam = {};
> >          struct netdev_rx_queue *rxq;
> >          u32 xa_idx;
> >          int err;
> > @@ -146,6 +150,20 @@ int net_devmem_bind_dmabuf_to_queue(struct net_device *dev, u32 rxq_idx,
> >                  return -EEXIST;
> >          }
> >
> > +       if (!dev->ethtool_ops->get_ringparam) {
> > +               NL_SET_ERR_MSG(extack, "can't get ringparam");
> > +               return -EINVAL;
> > +       }
>
> Is EINVAL the correct return value here? I think it makes more sense as
> EOPNOTSUPP.

Yes, Thanks for catching this.

>
> > +
> > +       dev->ethtool_ops->get_ringparam(dev, &ringparam,
> > +                                       &kernel_ringparam, extack);
> > +       if (kernel_ringparam.tcp_data_split != ETHTOOL_TCP_DATA_SPLIT_ENABLED ||
> > +           kernel_ringparam.tcp_data_split_thresh) {
> > +               NL_SET_ERR_MSG(extack,
> > +                              "tcp-header-data-split is disabled or threshold is not zero");
> > +               return -EINVAL;
> > +       }
> > +
> Maybe just my personal opinion, but IMHO these checks should be separate
> so the error message can be more concise/clear.

I agree, the error message is not clear, it contains two conditions.

>
> Also, a small nit, but I think both of these checks should be before
> getting the rxq via __netif_get_rx_queue().
>

I will drop this patch in a v4 patch.

Thanks a lot!
Taehee Yoo

>
> Thanks,
>
> Brett
> >   #ifdef CONFIG_XDP_SOCKETS
> >          if (rxq->pool) {
> >                  NL_SET_ERR_MSG(extack, "designated queue already in use by AF_XDP");
> > --
> > 2.34.1
> >