Re: [PATCH net-next v5] net: pppoe: implement GRO/GSO support

Qingfang Deng <[email protected]> Fri, 27 Mar 2026 09:48:53 +0800

Newsgroups	org.kernel.vger.linux-ppp,org.kernel.vger.linux-kernel,org.kernel.vger.netdev
Message-ID	<CALW65javKc9H1zQ4m5cb0qPfXix+bWM9LcVZ+uQN5BdgdTQ=gQ@mail.gmail.com>

Hi,

On Thu, Mar 26, 2026 at 10:44 PM Xin Long <[email protected]> wrote:
>
> On Thu, Mar 26, 2026 at 10:43 AM Xin Long <[email protected]> wrote:
> >
> > On Wed, Mar 25, 2026 at 10:43 PM Qingfang Deng <[email protected]> wrote:
> > >
> > > Hi all,
> > >
> > > In some cases (such as BIG TCP) a GRO skb length can overflow a u16,
> > > then what should I do with the u16 length field here?
> >
> > I think you can either add a check in pppoe_gro_complete() to ensure
> sorry, I meant add a check in pppoe_gro_receive().
> > the aggregated size does not exceed U16_MAX, avoiding BIG TCP
> > behavior; Or, set phdr->length to 0 and rely on skb->len to determine
> > the actual length, as done in BIG TCP itself.

In my v6 patch, I set phdr->length to 0xFFFF. Is that okay?

https://lore.kernel.org/netdev/[email protected]/