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From: Florian Westphal <fw@strlen.de>
To: Pablo Neira Ayuso <pablo@netfilter.org>
Cc: Qi Tang <tpluszz77@gmail.com>,
	netfilter-devel@vger.kernel.org, netdev@vger.kernel.org,
	herbert@gondor.apana.org.au, michael.bommarito@gmail.com,
	lyutoon@gmail.com
Subject: Re: [RFC] netfilter: disable payload mangling in userns
Date: Mon, 18 May 2026 15:39:18 +0200	[thread overview]
Message-ID: <agsWhgktcApPkJY7@strlen.de> (raw)
In-Reply-To: <agr9ry_EKdTfgoaj@chamomile>

Pablo Neira Ayuso <pablo@netfilter.org> wrote:
> > I think we have to update nfqueue to do rudimentary header revalidation
> > and drop the packet on failure, e.g. at least making sure tot_len is not
> > past skb->len.
> 
> Agreed, nfqueue has been there for long time and such parser would
> validate the packet is correct from stack POV.
> 
> But if a new function to validate that the IP header mangling is not
> valid is feasible, then why not simply apply the same sanitization
> from inet hooks to nft_payload/nft_exthdr?

Ok, I will have a look.  Thanks for the feedback.

      reply	other threads:[~2026-05-18 13:39 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-05-15 10:04 [RFC] netfilter: disable payload mangling in userns Florian Westphal
2026-05-15 11:48 ` Qi Tang
2026-05-15 12:48   ` Florian Westphal
2026-05-18 11:53     ` Pablo Neira Ayuso
2026-05-18 13:39       ` Florian Westphal [this message]

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