From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp105.iad3a.emailsrvr.com (smtp105.iad3a.emailsrvr.com [173.203.187.105]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.bufferbloat.net (Postfix) with ESMTPS id E61A33CB35 for ; Thu, 4 Jan 2018 17:02:46 -0500 (EST) Received: from smtp14.relay.iad3a.emailsrvr.com (localhost [127.0.0.1]) by smtp14.relay.iad3a.emailsrvr.com (SMTP Server) with ESMTP id 74A2625324; Thu, 4 Jan 2018 17:02:46 -0500 (EST) X-SMTPDoctor-Processed: csmtpprox beta Received: from smtp14.relay.iad3a.emailsrvr.com (localhost [127.0.0.1]) by smtp14.relay.iad3a.emailsrvr.com (SMTP Server) with ESMTP id 6DC73253D4; Thu, 4 Jan 2018 17:02:46 -0500 (EST) Received: from app6.wa-webapps.iad3a (relay-webapps.rsapps.net [172.27.255.140]) by smtp14.relay.iad3a.emailsrvr.com (SMTP Server) with ESMTP id 5098125324; Thu, 4 Jan 2018 17:02:46 -0500 (EST) X-Sender-Id: dpreed@deepplum.com Received: from app6.wa-webapps.iad3a (relay-webapps.rsapps.net [172.27.255.140]) by 0.0.0.0:25 (trex/5.7.12); Thu, 04 Jan 2018 17:02:46 -0500 Received: from deepplum.com (localhost.localdomain [127.0.0.1]) by app6.wa-webapps.iad3a (Postfix) with ESMTP id 40741E056C; Thu, 4 Jan 2018 17:02:46 -0500 (EST) Received: by apps.rackspace.com (Authenticated sender: dpreed@deepplum.com, from: dpreed@deepplum.com) with HTTP; Thu, 4 Jan 2018 17:02:46 -0500 (EST) X-Auth-ID: dpreed@deepplum.com Date: Thu, 4 Jan 2018 17:02:46 -0500 (EST) From: "dpreed@deepplum.com" To: "=?utf-8?Q?Joel_Wir=C4=81mu_Pauling?=" Cc: "Jonathan Morton" , cerowrt-devel@lists.bufferbloat.net MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_20180104170246000000_84689" Importance: Normal X-Priority: 3 (Normal) X-Type: html Message-ID: <1515103366.261714700@apps.rackspace.com> X-Mailer: webmail/12.9.10-RC Subject: Re: [Cerowrt-devel] =?utf-8?q?KASLR=3A_Do_we_have_to_worry_about_othe?= =?utf-8?q?r_arches_than_x86=3F?= X-BeenThere: cerowrt-devel@lists.bufferbloat.net X-Mailman-Version: 2.1.20 Precedence: list List-Id: Development issues regarding the cerowrt test router project List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 04 Jan 2018 22:02:47 -0000 ------=_20180104170246000000_84689 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable =0AHmm... protection datacentres tend to require lower latencies than can b= e achieved running on hypervisors.=0A =0AWhich doesn't mean that some datac= enters don't do that.=0A =0AAs far as NFV is concerned, Meltdown only break= s security if a userspace application is running on a machine where another= user has data running through kernel address space. NFV environments don't= tend to run NFV in userspace under an OS that has kernel data in the page = tables that are reachable from CR3.=0A =0AThe key issue in Meltdown is that= CR3 is not changed between userspace and kernelspace. Which means that the= memory access pipeline in userspace can use a kernelspace address (what In= tel calls a "linear" address) without a check that the pagetables enable us= erspace access. The check happens after the speculative execution of the me= mory access.=0A =0AI repeat this, because many pseudo-experts who love to b= e quoted in the press as saying "be afraid, be very afraid" are saying a lo= t of nonsense about Meltdown and Sceptre. It seems to be an echo chamber ef= fect - the papers were released yesterday afternoon, but in a rush to get "= quoted", all the wannabe-quoted people are saying things that are just plai= n NOT TRUE.=0A =0A =0A-----Original Message-----=0AFrom: "Joel Wir=C4=81mu = Pauling" =0ASent: Thursday, January 4, 2018 4:44pm=0ATo:= "Jonathan Morton" =0ACc: cerowrt-devel@lists.buffer= bloat.net=0ASubject: Re: [Cerowrt-devel] KASLR: Do we have to worry about o= ther arches than x86?=0A=0A=0A=0A=0A=0A=0AOn 5 January 2018 at 01:09, Jonat= han Morton <[ chromatix99@gmail.com ]( mailto:chromatix99@gmail.com )> wrot= e:=0A=0A=0A I don't think we need to worry about it too much in a router co= ntext. Virtual server folks, OTOH...=0A=0A=0A=0A - Jonathan Morton=0A=0A= =0A=0A=E2=80=8BDisagree - The Router is pretty much synonymous with NFV=E2= =80=8B =0A=E2=80=8B; I run my lede instances at home on hypervisors - and t= his is definitely the norm in Datacentres now. We need to work through this= quite carefully. =E2=80=8B ------=_20180104170246000000_84689 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable

Hmm... protection datacentres tend to require lower latencies than can be = achieved running on hypervisors.

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Which does= n't mean that some datacenters don't do that.

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As far as NFV is concerned, Meltdown only breaks security if a userspace= application is running on a machine where another user has data running th= rough kernel address space. NFV environments don't tend to run NFV in users= pace under an OS that has kernel data in the page tables that are reachable= from CR3.

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=0A<= p style=3D"margin:0;padding:0;margin: 0; padding: 0; font-family: arial; fo= nt-size: 10pt; overflow-wrap: break-word;">The key issue in Meltdown is tha= t CR3 is not changed between userspace and kernelspace. Which means that th= e memory access pipeline in userspace can use a kernelspace address (what I= ntel calls a "linear" address) without a check that the pagetables enable u= serspace access. The check happens after the speculative execution of the m= emory access.

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I repeat this, because many = pseudo-experts who love to be quoted in the press as saying "be afraid, be = very afraid" are saying a lot of nonsense about Meltdown and Sceptre. It se= ems to be an echo chamber effect - the papers were released yesterday after= noon, but in a rush to get "quoted", all the wannabe-quoted people are sayi= ng things that are just plain NOT TRUE.

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&nb= sp;

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-----Original Message= -----
From: "Joel Wir=C4=81mu Pauling" <joel@aenertia.net>
= Sent: Thursday, January 4, 2018 4:44pm
To: "Jonathan Morton" <chrom= atix99@gmail.com>
Cc: cerowrt-devel@lists.bufferbloat.net
Subj= ect: Re: [Cerowrt-devel] KASLR: Do we have to worry about other arches than= x86?

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On 5 Ja= nuary 2018 at 01:09, Jonathan Morton <chromatix99@gmail.com> wrote:
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I don= 't think we need to worry about it too much in a router context.  Virt= ual server folks, OTOH...
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 - Jonathan Morton

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=E2=80=8BDisagree - The Router is pretty much syno= nymous with NFV=E2=80=8B
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=E2=80=8B; I run my= lede instances at home on hypervisors - and this is definitely the norm in= Datacentres now. We need to work through this quite carefully. =E2=80=8B=0A
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