Re: [PATCH 3/4] net-next: frags: add inetpeer frag_mem tracking

From: Eric Dumazet
Date: Thu Sep 01 2022 - 12:07:27 EST


On Thu, Sep 1, 2022 at 8:03 AM Richard Gobert <richardbgobert@xxxxxxxxx> wrote:
>
> On Mon, Aug 29, 2022 at 03:15:47PM -0700, Eric Dumazet wrote:
> > We tried to get rid of any dependence over inetpeer, which is not
> > resistant against DDOS attacks.
> >
> > So I would not add a new dependency.
>
> I see your point. What do you suggest doing differently?
>
> The inetpeer mechanism is used for IPv4 frags. If it isn't resistant
> against DDoS attacks, can it perhaps be improved?

It can be disabled if needed, by changing ipfrag_max_dist sysctl.

Quite frankly IPv4 reassembly unit is a toy, I am always surprised
some applications are still relying on IP fragments.