From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from Chamillionaire.breakpoint.cc (Chamillionaire.breakpoint.cc [91.216.245.30]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E3C312931F5 for ; Mon, 24 Aug 2026 19:56:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.216.245.30 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787601411; cv=none; b=PpDboCZRfel+gYTFsoHbCaTu96lZREO+t2UW6t7mXKn+etAnoYj82YWlKoxykF2vMtaj/VQZ0scamNSZtdleXol33PGcUBNvZ0DBqT8a4mR8UiaZUh9dZ6Baa2tNF7BHRfpFZsKwtC5KzV1JELou/l144KekOQwbVX9bnNuRbPQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787601411; c=relaxed/simple; bh=d/sexpj4nf8NbLIPRBTxnG1vmqg/YyjiaM1wKDEZ1Fk=; h=Date:From:To:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=NABogRSL1MmWazDzWP1A0M4dg0d7S5SA8kvKU8eXGOLFJ3Exg48GvTwYqsXeIZYSFE+mxABY3Zzxx8X5Xv+tYFkgaCfJH3antQxUmQriGZWIphBCcQawsZDrM3mQ/ssbtqXqH95/rXUutVHR4We+AIG6ya5c/1EQUy3PziK5iwo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=strlen.de; spf=pass smtp.mailfrom=strlen.de; arc=none smtp.client-ip=91.216.245.30 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=strlen.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=strlen.de Received: by Chamillionaire.breakpoint.cc (Postfix, from userid 1003) id A439360388; Mon, 24 Aug 2026 21:56:47 +0200 (CEST) Date: Mon, 24 Aug 2026 21:56:46 +0200 From: Florian Westphal To: netfilter-devel@vger.kernel.org Subject: Re: [PATCH nf] netfilter: nft_payload: restrict checksum offsets to known values Message-ID: References: <20260824192843.28439-1-fw@strlen.de> Precedence: bulk X-Mailing-List: netfilter-devel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260824192843.28439-1-fw@strlen.de> Florian Westphal wrote: > We need to prevent userspace from corrupting e.g. tcp->doff, because > many locations in conntrack and conntrack helpers rely on > nf_conntrack_in() having validated the packet headers. > nft_payload allows to alter headers later which invalidates this > assumption. https://sashiko.dev/#/patchset/20260824192843.28439-1-fw%40strlen.de Can't make sense of it, afaics this patch is fine.