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Date: Thu, 20 Aug 2026 19:37:10 +0200
From: Florian Westphal <fw@strlen.de>
To: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: netdev@vger.kernel.org, jiri@resnulli.us, victor@mojatatu.com
Subject: Re: [PATCH net 0/4] net/sched: reset conntrack after packet munging
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Jamal Hadi Salim <jhs@mojatatu.com> wrote:
> > Yes, e.g. what if pedit inflated th->doff?
> > nf_conntrack_in() checked that this was fine, but now the pipeline
> > can re-neg on that.
> 
> True.
> So my question to you then is: what about BPF, OVS, future thingy? Are
> you going to fix each individually?

I see no alternative?  I mean, what are you suggesting?
We can apply the patch from Kyle, that will stop the reproducer.
But I can tell you that we'll need hundreds of followup patches
all over.

I mean, we always relied on IP stack having checked that iph->ihl is
fine, the ipv6 header is complete, etc.

And that isn't exclusive to netfilter.

My best suggestion is to remove skb->_nfct and reparse everywhere,
but I will NOT make such a patch, IMO conntrack and netfilter might
as well be axed then.  Hey, would solve a few bugs.