From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 472103C9EEB; Mon, 29 Jun 2026 22:42:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782772950; cv=none; b=H2xsMSTgyPwI2X7lLeanp0ZUf+49h7a6exaEXi7m7Rb9jtfDTN0SsNLkk1hpGz5ZYaiZ4JGVFsrdiGRxlVWtZji7HpKWunrvOBt9hobiOuO8L4+N06YpKV52SrtVNo0hhJlPacDbYEg5xl6BNFI11Pl58uLLqEHGdG6xdEXDgQQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782772950; c=relaxed/simple; bh=Y1FUyUQ+6pDo3Q5u+Ak9XpYlYqm3oNTdVvT0dujNB3g=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=EoN4dKKOzxgBAIYrBp7hjzJacQhHN/uf2Z4fqfd4mip3Ep8Z/0HXK4Q43iWDJ3ldTkrdTo4wjOQld1trI+QkCU6tyloFWJtiVD49eZGdOiA94uc6wcbbTo/q6KxhklPYINdSL2omez93nZSKM1Sa9ok0Rus5JaYZESh6CqnR+14= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=NrAiodgO; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="NrAiodgO" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 735301F000E9; Mon, 29 Jun 2026 22:42:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1782772948; bh=dfGsgo+yOeIxzkSlnKWKokDKNnAd9uFqZ03mLJMQ/38=; h=Date:From:To:Cc:Subject:In-Reply-To:References; b=NrAiodgObb2yFqGGJQri6AIaCve5EmL2LVTm6FpN01BrRMSNXahENgpFLJAahKPOi ExapQOm/WvJl1AO2YcwcAG2x8sg3jmsvc9e48/n9JN5sIr8koTWYFEL26+vyr3GanM 9mC2jOadOH1TrlWpeDkNti3BwaWvfSVKEKykoiUU53Pf/uqEdEwcXiMkzssDjuPyEq fpF8U5r4y3GTBMZNi/hjcFvH319MhdwJ6q7Py5ShfPZnnjuyFtC6a/lr2UUJYcdKVj Ge43D38j4hwNblZ0DZ9nzuUebhZLUOsDpAgk+OZpPlMszbdFPLX9O61Kbyb1qaJNPR gTg6gMY8i77HQ== Date: Mon, 29 Jun 2026 15:42:27 -0700 From: Jakub Kicinski To: Samuel Moelius Cc: Toke =?UTF-8?B?SMO4aWxhbmQtSsO4cmdlbnNlbg==?= , Jamal Hadi Salim , Jiri Pirko , "David S. Miller" , Eric Dumazet , Paolo Abeni , Simon Horman , "moderated list:CAKE QDISC" , "open list:TC subsystem" , open list Subject: Re: [PATCH net v2] net/sched: cake: reject overhead values that underflow length Message-ID: <20260629154227.741f2051@kernel.org> In-Reply-To: References: <20260609232935.1602659.8545fdb04fbe.cake-overhead-underflow@trailofbits.com> <20260613142626.1b2183eb@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable On Mon, 29 Jun 2026 14:44:28 -0400 Samuel Moelius wrote: > On Mon, Jun 29, 2026 at 1:24=E2=80=AFPM Samuel Moelius > wrote: > > > > On Sat, Jun 13, 2026 at 5:26=E2=80=AFPM Jakub Kicinski wrote: =20 > > > > > > On Tue, 9 Jun 2026 23:29:36 +0000 Samuel Moelius wrote: =20 > [...] =20 > > > > > > Both Sashiko's complain - these values are neither safe nor sufficien= t. > > > > > > How was the -64 chosen? It looks suspiciously close the min ethernet > > > frame length. =20 > > > > That's how it was chosen. But as you've shown, it was not a good choice. > > > > I would like to submit a revised patch that does the check on the > > datapath, as you suggested. Should I send that patch? Or would you > > prefer to wait for a response from Toke? =20 >=20 > Apologies. I just noticed Toke did reply. Should I send a patch > consistent with what he suggested? Yes please