From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from w4.tutanota.de (w4.tutanota.de [81.3.6.165]) (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 E019F55C07 for ; Mon, 18 Mar 2024 17:58:12 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=81.3.6.165 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1710784698; cv=none; b=Z9epKYFxdWAcj85cN803RQKvXXUSBhq35hQpz8hmUwCOcywPhvAZtFiTq0qElYuv9JIfA7vp6ACAoI9Goa/tDHUKGv70egbUv79FPNfvjUl2/YHr7SfuPTDsH92JNIjH43F52kTV/DYcp+oaz8UwTIj0YbW07VQEOYeXzcVE/hI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1710784698; c=relaxed/simple; bh=BozJnYrBkjqHICJFMZVYfh7cFw/AHonryra8lQWiM3s=; h=Date:From:To:Cc:Message-ID:In-Reply-To:References:Subject: MIME-Version:Content-Type; b=QOtFIwF3J7uHuQrpXzNF6fG348EA7bBe5PX0KFmwGGfo2svMYdwOUhEZi/viLJCJCXBB+wxudmKtw7FIDbMHxLXKeJG33Fe269h/HqdedJ2CPiN4JgRWIIb4q/dWmD+ZF9pQnyEM++32pjwtxOyeZrG9mULbiwBcb0e6BqV91Ao= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=lynne.ee; spf=pass smtp.mailfrom=lynne.ee; dkim=pass (2048-bit key) header.d=lynne.ee header.i=@lynne.ee header.b=JUBwSPJs; arc=none smtp.client-ip=81.3.6.165 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=lynne.ee Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=lynne.ee Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=lynne.ee header.i=@lynne.ee header.b="JUBwSPJs" Received: from tutadb.w10.tutanota.de (unknown [192.168.1.10]) by w4.tutanota.de (Postfix) with ESMTP id C867710602E7; Mon, 18 Mar 2024 17:58:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; t=1710784690; s=s1; d=lynne.ee; h=From:From:To:To:Subject:Subject:Content-Description:Content-ID:Content-Type:Content-Type:Content-Transfer-Encoding:Content-Transfer-Encoding:Cc:Cc:Date:Date:In-Reply-To:In-Reply-To:MIME-Version:MIME-Version:Message-ID:Message-ID:Reply-To:References:References:Sender; bh=BozJnYrBkjqHICJFMZVYfh7cFw/AHonryra8lQWiM3s=; b=JUBwSPJsxT86n0OhW4NjRg3SrrDA/hu0vgZrx4TlREJukHlF9FhGICgfirvOIP8b DZFNBGaR91y2qedmCLDjWw4QBhUmJsclwKlHnXLUyJAQ3hYOkFjDYQ4OrhkUSw2HE31 vyKKj2lDLXkND97bRXkxN1g2wNn48twHjY0p9dApzg6aJ/mYXjNz1dPNcIcdh0CuG0I vFYRM6Bhpk6P2N8JxRsEVzsnjh7EJdLA7lm/tXgkGTrFRR7KFUQ52q8okEEDy1k9d1L oc+3UrwFiuFGMqmHMOrNLWV3/2SM4EzrxTtw+PKWF8jpyAZDRMoHuMJtzBy5Nucuf6B WmHvOMymhQ== Date: Mon, 18 Mar 2024 18:58:10 +0100 (CET) From: Lynne To: Florian Westphal Cc: Netdev , Kuniyu , Willemdebruijn Kernel Message-ID: In-Reply-To: References: Subject: Re: Regarding UDP-Lite deprecation and removal Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Mar 18, 2024, 14:18 by fw@strlen.de: > Lynne wrote: > >> UDP-Lite was scheduled to be removed in 2025 in commit >> be28c14ac8bbe1ff due to a lack of real-world users, and >> a long-outstanding security bug being left undiscovered. >> >> I would like to open a discussion to perhaps either avoid this, >> or delay it, conditionally. >> > > Is there any evidence UDP-Lite works in practice? > > I am not aware of any HW that will peek into L3/L4 payload to figure out > that the 'udplite' payload should be passed up even though it has bad csum. > > So, AFAIU L2 FCS/CRC essentially renders entire 'partial csum' premise moot, > stack will never receive udplite frames that are damaged. > > Did things change? > I do somehow get CRC errors past the Ethernet layer on consumer rtl cards, by default, with no ethtool changes, so maybe things did change. I haven't sacrificed a good cable yet to get a definitive proof. The cargo-culted way to be sure is to enable rx-all.