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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 85E3CC433EF for ; Mon, 7 Feb 2022 16:30:57 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 1BB816B0074; Mon, 7 Feb 2022 11:30:57 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 143F76B0075; Mon, 7 Feb 2022 11:30:57 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id F2D246B0078; Mon, 7 Feb 2022 11:30:56 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0028.hostedemail.com [216.40.44.28]) by kanga.kvack.org (Postfix) with ESMTP id DD90B6B0074 for ; Mon, 7 Feb 2022 11:30:56 -0500 (EST) Received: from smtpin11.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 96831180BE3A7 for ; Mon, 7 Feb 2022 16:30:56 +0000 (UTC) X-FDA: 79116522912.11.4BB41D6 Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by imf28.hostedemail.com (Postfix) with ESMTP id 959D4C0015 for ; Mon, 7 Feb 2022 16:30:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1644251455; x=1675787455; h=message-id:date:mime-version:to:cc:references:from: subject:in-reply-to:content-transfer-encoding; bh=/KVSVa7sgjsVxefcYGnYLwrI2Vchw9qvwnAjpTnywCY=; b=cIYioXmbBva7GiK2S6V/kHNNMQ42T5/+219mcMD73sxYmhJ1LlRzNbRa vbYa8VlyOfouRm1bFhPbAjLsGl2bjuVCh4rD7t2ep2rWzEjLNFc6aT5gc umi21HDz+xer1bgxennJR44V7uWJyRCFtCZgg5k1tSkQjj+8ifpv5bI4y WI0iVvpaV25xE5Jly/APRYHTWW8CKt7yGD7ArALungse6H24MRr4lpZOT kZucL/Tmizr0HougnxrD3vK5mGb0CSfGWITssxYJZH+xFEk23u4OAlSkv xJmTMclsWt7wOWVHcOpkyt29yKS52Q1zu8It/Za+MU97C8VqMj/ZYc0e4 w==; X-IronPort-AV: E=McAfee;i="6200,9189,10250"; a="236155235" X-IronPort-AV: E=Sophos;i="5.88,350,1635231600"; d="scan'208";a="236155235" Received: from orsmga007.jf.intel.com ([10.7.209.58]) by orsmga101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 07 Feb 2022 08:30:54 -0800 X-IronPort-AV: E=Sophos;i="5.88,350,1635231600"; d="scan'208";a="525193372" Received: from hgrunes-mobl1.amr.corp.intel.com (HELO [10.251.3.57]) ([10.251.3.57]) by orsmga007-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 07 Feb 2022 08:30:53 -0800 Message-ID: <8f96c2a6-9c03-f97a-df52-73ffc1d87957@intel.com> Date: Mon, 7 Feb 2022 08:30:50 -0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.5.0 Content-Language: en-US To: Adrian Reber , Mike Rapoport Cc: Rick Edgecombe , x86@kernel.org, "H . Peter Anvin" , Thomas Gleixner , Ingo Molnar , linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, linux-mm@kvack.org, linux-arch@vger.kernel.org, linux-api@vger.kernel.org, Arnd Bergmann , Andy Lutomirski , Balbir Singh , Borislav Petkov , Cyrill Gorcunov , Dave Hansen , Eugene Syromiatnikov , Florian Weimer , "H . J . Lu" , Jann Horn , Jonathan Corbet , Kees Cook , Mike Kravetz , Nadav Amit , Oleg Nesterov , Pavel Machek , Peter Zijlstra , Randy Dunlap , "Ravi V . Shankar" , Dave Martin , Weijiang Yang , "Kirill A . Shutemov" , joao.moreira@intel.com, John Allen , kcc@google.com, eranian@google.com, Andrei Vagin , Dmitry Safonov <0x7f454c46@gmail.com> References: <20220130211838.8382-1-rick.p.edgecombe@intel.com> From: Dave Hansen Subject: Re: [PATCH 00/35] Shadow stacks for userspace In-Reply-To: Content-Type: text/plain; charset=UTF-8 X-Stat-Signature: d6kb6sgab6dideuwqpywujo8wsonrgyt X-Rspam-User: nil Authentication-Results: imf28.hostedemail.com; dkim=pass header.d=intel.com header.s=Intel header.b=cIYioXmb; spf=none (imf28.hostedemail.com: domain of dave.hansen@intel.com has no SPF policy when checking 134.134.136.20) smtp.mailfrom=dave.hansen@intel.com; dmarc=pass (policy=none) header.from=intel.com X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: 959D4C0015 X-HE-Tag: 1644251455-805481 Content-Transfer-Encoding: quoted-printable X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On 2/6/22 23:20, Adrian Reber wrote: >>> CRIU Support >>> ------------ >>> In the past there was some speculation on the mailing list about=20 >>> whether CRIU would need to be taught about CET. It turns out, it doe= s.=20 >>> The first issue hit is that CRIU calls sigreturn directly from its=20 >>> =E2=80=9Cparasite code=E2=80=9D that it injects into the dumper proc= ess. This violates >>> this shadow stack implementation=E2=80=99s protection that intends t= o prevent >>> attackers from doing this. ... >>>From the CRIU side I can say that I would definitely like to see this > resolved. CRIU just went through a similar exercise with rseq() being > enabled in glibc and CI broke all around for us and other projects > relying on CRIU. Although rseq() was around for a long time we were not > aware of it but luckily 5.13 introduced a way to handle it for CRIU wit= h > ptrace. An environment variable existed but did not really help when > CRIU is called somewhere in the middle of the container software stack. >=20 >>>From my point of view a solution not involving an environment variable > would definitely be preferred. Have there been things like this for CRIU in the past? Something where CRIU needs control but that's also security-sensitive? Any thoughts on how you would _like_ to see this resolved?