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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no 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 936CBC433E0 for ; Wed, 20 May 2020 21:02:58 +0000 (UTC) Received: from fraxinus.osuosl.org (smtp4.osuosl.org [140.211.166.137]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 1FC4B2075F for ; Wed, 20 May 2020 21:02:57 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1FC4B2075F Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=ubuntu.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=ksummit-discuss-bounces@lists.linuxfoundation.org Received: from localhost (localhost [127.0.0.1]) by fraxinus.osuosl.org (Postfix) with ESMTP id CEE1D8718F; Wed, 20 May 2020 21:02:57 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from fraxinus.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id sCQthG2gfZik; Wed, 20 May 2020 21:02:57 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by fraxinus.osuosl.org (Postfix) with ESMTP id 4C7AA87195; Wed, 20 May 2020 21:02:57 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id F2260C088A; Wed, 20 May 2020 21:02:56 +0000 (UTC) Received: from whitealder.osuosl.org (smtp1.osuosl.org [140.211.166.138]) by lists.linuxfoundation.org (Postfix) with ESMTP id BA603C0176 for ; Wed, 20 May 2020 21:02:54 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by whitealder.osuosl.org (Postfix) with ESMTP id B5F5287F9A for ; Wed, 20 May 2020 21:02:54 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from whitealder.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id ZN7zDDDurVl1 for ; Wed, 20 May 2020 21:02:54 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from youngberry.canonical.com (youngberry.canonical.com [91.189.89.112]) by whitealder.osuosl.org (Postfix) with ESMTPS id D212987CB0 for ; Wed, 20 May 2020 21:02:53 +0000 (UTC) Received: from ip5f5af183.dynamic.kabel-deutschland.de ([95.90.241.131] helo=wittgenstein) by youngberry.canonical.com with esmtpsa (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.86_2) (envelope-from ) id 1jbVrX-0007LP-Qu; Wed, 20 May 2020 21:02:51 +0000 Date: Wed, 20 May 2020 23:02:51 +0200 From: Christian Brauner To: Kees Cook Message-ID: <20200520210251.goxnb2mq4lkhobms@wittgenstein> References: <202005200917.71E6A5B20@keescook> <20200520163102.GZ23230@ZenIV.linux.org.uk> <202005201104.72FED15776@keescook> <202005201151.AFA3C9E@keescook> <20200520202401.s22hstao4kzr5uma@wittgenstein> <202005201340.ED17EDC@keescook> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <202005201340.ED17EDC@keescook> Cc: Aleksa Sarai , ksummit Subject: Re: [Ksummit-discuss] [TECH TOPIC] seccomp feature development X-BeenThere: ksummit-discuss@lists.linuxfoundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: ksummit-discuss-bounces@lists.linuxfoundation.org Sender: "Ksummit-discuss" On Wed, May 20, 2020 at 01:52:30PM -0700, Kees Cook wrote: > On Wed, May 20, 2020 at 10:24:01PM +0200, Christian Brauner wrote: > > On Wed, May 20, 2020 at 12:08:52PM -0700, Linus Torvalds wrote: > > > On Wed, May 20, 2020 at 12:04 PM Kees Cook wrote: > > > > Perhaps the question is "how deeply does seccomp need to inspect?" > > > > and maybe it does not get to see anything beyond just the "top level" > > > > struct (i.e. struct clone_args) and all pointers within THAT become > > > > opaque? That certainly simplifies the design. > > > > > > Exactly. I think that's the most common situation by far. Does anybody > > > really really need to care at a deep level, and why? > > > > We mostly don't and making all second-level pointers opaque is ok imho. > > That'll make things MUCH easier. :) > > > But I think that we need some documented consensus on all that stuff > > which I stressed in other mails before. I'll hand something in about > > this, if that's ok than we can hash this out. > > Aleksa, I know you had an entire presentation[1] on the extensible > argument syscalls, but was there any text-based design doc that you made? > > It would be really nice to update Documentation/process/adding-syscalls.rst > with the specifics[2], and to (now) include the "no nested flags" > requirement. What do you think? I've sent out: https://lore.kernel.org/linux-doc/20191002151437.5367-1-christian.brauner@ubuntu.com/ a while back which we drafted together specifically to documented extensible syscalls. I wanted to resend it this week. I'll update it with all register based flag arguments should be unsigned int which I already droned about this week in another thread. The no nested flags requirement can go in there as well. Aleksa and I also had a joint session for Plumbers/Ksummit planned hence the "handing something in". Christian _______________________________________________ Ksummit-discuss mailing list Ksummit-discuss@lists.linuxfoundation.org https://lists.linuxfoundation.org/mailman/listinfo/ksummit-discuss