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=-5.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 06FE1C5519F for ; Sun, 22 Nov 2020 21:00:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B769120782 for ; Sun, 22 Nov 2020 21:00:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727813AbgKVVAf (ORCPT ); Sun, 22 Nov 2020 16:00:35 -0500 Received: from jabberwock.ucw.cz ([46.255.230.98]:42558 "EHLO jabberwock.ucw.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727418AbgKVVAf (ORCPT ); Sun, 22 Nov 2020 16:00:35 -0500 Received: by jabberwock.ucw.cz (Postfix, from userid 1017) id 46B251C0BA9; Sun, 22 Nov 2020 22:00:32 +0100 (CET) Date: Sun, 22 Nov 2020 22:00:31 +0100 From: Pavel Machek To: Tushar Sugandhi Cc: zohar@linux.ibm.com, stephen.smalley.work@gmail.com, casey@schaufler-ca.com, agk@redhat.com, snitzer@redhat.com, gmazyland@gmail.com, paul@paul-moore.com, tyhicks@linux.microsoft.com, sashal@kernel.org, jmorris@namei.org, nramas@linux.microsoft.com, linux-integrity@vger.kernel.org, selinux@vger.kernel.org, linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org, dm-devel@redhat.com Subject: Re: [PATCH v6 0/8] IMA: support for measuring kernel integrity critical data Message-ID: <20201122210031.GA26756@amd> References: <20201119232611.30114-1-tusharsu@linux.microsoft.com> <20201120124657.GA31468@duo.ucw.cz> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="PEIAKu/WMn1b1Hv9" Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.23 (2014-03-12) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --PEIAKu/WMn1b1Hv9 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Hi! > >How is it supposed to be useful? > > > >I'm pretty sure there are critical data that are not measured by > >proposed module... and that are written under normal circumstances. > > > The goal of this series is to introduce the IMA hook > measure_critical_data() and the necessary policies to use it; and > illustrate that use with one example (SELinux). It is not scalable to > identify and update all the critical data sources to use the proposed > module at once. >=20 > A piecemeal approach to add more critical data measurement in subsequent > patches would be easy to implement and review. Basically every other data structure in kernel is "critical" by your definition, and you can't really measure them all; some of them change rather often. Going piecemeal does not really help here. Example of critical data structure: page table entries for process I own. Best regards, Pavel --=20 http://www.livejournal.com/~pavelmachek --PEIAKu/WMn1b1Hv9 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iEYEARECAAYFAl+60W8ACgkQMOfwapXb+vIcigCeMzGk7j6mjC+lCez6JgfwCYJI Z1YAnihbhsor2KAe3Vx6iXF3suE279VG =O8SH -----END PGP SIGNATURE----- --PEIAKu/WMn1b1Hv9--