From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS, URIBL_BLOCKED,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 36C6EC43142 for ; Fri, 3 Aug 2018 03:13:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D1D0B216EE for ; Fri, 3 Aug 2018 03:13:26 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=ozlabs.org header.i=@ozlabs.org header.b="j1+OC/9s" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D1D0B216EE Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=ozlabs.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728284AbeHCFHe (ORCPT ); Fri, 3 Aug 2018 01:07:34 -0400 Received: from ozlabs.org ([203.11.71.1]:42337 "EHLO ozlabs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726353AbeHCFHe (ORCPT ); Fri, 3 Aug 2018 01:07:34 -0400 Received: by ozlabs.org (Postfix, from userid 1003) id 41hXDf01cyz9s3Z; Fri, 3 Aug 2018 13:13:21 +1000 (AEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ozlabs.org; s=201707; t=1533266002; bh=UYbEv5KLltTctk3RA2mBy4F74bubu9dPJuuEIjnxR+A=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=j1+OC/9sDuTl/qRuMd2SaomwBOUl2TQEaPTWk8OqSfLjVeBpmid4WyFrYx+iCkN52 FJoTeQSYtHVFNzw0F8BIUZe8wLRnORzvydFPSdSmEzNoBFVcrBoM811xY629is77M0 b3v4rs8Ty8yrnSjhknHqNoCTXcLpAVtOI/HUkEuyea+eNm/73aA2jeOw0Wk7cC/oSc ZY1uw5h76JES00qbBhj7ZjtCp3hl8om1OrkZROV5uU6MiAzSTq0JHvzpoC2q0zNBUM QNtKIfcN/m6wDckr3BhMyUHWcc4Qe2YmqkSvjwsXOoQrQUZub8RjX2+qIzHSldWQAc wBo8CshRUZFmA== Date: Fri, 3 Aug 2018 13:13:15 +1000 From: Paul Mackerras To: Kees Cook Cc: Arnd Bergmann , "David S. Miller" , Herbert Xu , Eric Biggers , "Gustavo A. R. Silva" , linux-ppp@vger.kernel.org, Networking , Linux Kernel Mailing List Subject: Re: [PATCH] ppp: mppe: Remove VLA usage Message-ID: <20180803031315.GA30807@fergus> References: <20180716040516.GA32783@beast> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Aug 02, 2018 at 04:27:01PM -0700, Kees Cook wrote: > On Mon, Jul 16, 2018 at 4:01 AM, Arnd Bergmann wrote: > > On Mon, Jul 16, 2018 at 6:05 AM, Kees Cook wrote: > >> In the quest to remove all stack VLA usage from the kernel[1], this > >> removes the discouraged use of AHASH_REQUEST_ON_STACK (and associated > >> VLA) by switching to shash directly and keeping the associated descriptor > >> allocated with the regular state on the heap. > >> > >> [1] https://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@mail.gmail.com > >> > >> Signed-off-by: Kees Cook > > > > I had concerns at first that this approach might make it slower, but > > upon reading through implementation of the shash_ahash_ implementation, > > I concluded that it can only be better than before, improving both > > performance and stack usage. > > > > Acked-by: Arnd Bergmann > > Paul, > > Is this something you can take via your tree? No, it would go via the netdev tree, I expect. Paul.