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=-5.6 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,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 3C322C4363A for ; Mon, 26 Oct 2020 16:52:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E7F00223B0 for ; Mon, 26 Oct 2020 16:52:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1603731144; bh=Xb2UwSkNcM9cbBM3zlY+jbuzH3M6a/pJtoQEPvBsp7k=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=jVyxS3yOKOrRvJOoPACGqHJaP/RegQfQMgnmUZIBW0Ef6RIhkRX/wx9dEjrwxAwvY u68TBYzSwkZ1x7DOI/7Unoe0EJvOdmScCWtN8T2RwWkDk5ppD/ooBIZQyaO1825NDX ia5U/9Yeod9Go8d/Y1IQEoiArL8h9F7maB7GXBNs= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1786551AbgJZQwR (ORCPT ); Mon, 26 Oct 2020 12:52:17 -0400 Received: from mail.kernel.org ([198.145.29.99]:44992 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1781267AbgJZQva (ORCPT ); Mon, 26 Oct 2020 12:51:30 -0400 Received: from localhost (fw-tnat.cambridge.arm.com [217.140.96.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 66404221FC; Mon, 26 Oct 2020 16:51:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1603731089; bh=Xb2UwSkNcM9cbBM3zlY+jbuzH3M6a/pJtoQEPvBsp7k=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=n0OeLdOtic5bPMHrJNTDAZZk8om61ybbk/lRM2morVVr0p0gU5pxKpJ4ky+5XuUFC Ueqjsz/CimTtIXrSzJ4EsJ+6cFUVL3htTzpmmNkqnHb/PeJeGrvVrRpv50GvRYw3O+ hsZProyK79R1Ngd6rjPchjVWWDcfW2JaFoFrTEA0= Date: Mon, 26 Oct 2020 16:51:25 +0000 From: Mark Brown To: Dave Martin Cc: Catalin Marinas , Topi Miettinen , Mark Rutland , Salvatore Mesoraca , systemd-devel@lists.freedesktop.org, Kees Cook , kernel-hardening@lists.openwall.com, Will Deacon , "linux-kernel@vger.kernel.org" , Jeremy Linton , linux-hardening@vger.kernel.org, libc-alpha@sourceware.org, "linux-arm-kernel@lists.infradead.org" Subject: Re: BTI interaction between seccomp filters in systemd and glibc mprotect calls, causing service failures Message-ID: <20201026165125.GF7402@sirena.org.uk> References: <8584c14f-5c28-9d70-c054-7c78127d84ea@arm.com> <20201022075447.GO3819@arm.com> <78464155-f459-773f-d0ee-c5bdbeb39e5d@gmail.com> <202010221256.A4F95FD11@keescook> <20201023090232.GA25736@gaia> <20201026145245.GD3117@gaia> <20201026155628.GA27285@arm.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="cpvLTH7QU4gwfq3S" Content-Disposition: inline In-Reply-To: <20201026155628.GA27285@arm.com> X-Cookie: Safety Third. User-Agent: Mutt/1.10.1 (2018-07-13) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --cpvLTH7QU4gwfq3S Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Mon, Oct 26, 2020 at 03:56:35PM +0000, Dave Martin wrote: > On Mon, Oct 26, 2020 at 02:52:46PM +0000, Catalin Marinas via Libc-alpha wrote: > > Now, if the dynamic loader silently ignores the mprotect() failure on > > the main executable, is there much value in exposing a flag in the aux > > vectors? It saves a few (one?) mprotect() calls but I don't think it > > matters much. Anyway, I don't mind the flag. > I don't see a problem with the aforementioned patch [2] to pre-set BTI > on the pages of the main binary. Me either FWIW. --cpvLTH7QU4gwfq3S Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAABCgAdFiEEreZoqmdXGLWf4p/qJNaLcl1Uh9AFAl+W/owACgkQJNaLcl1U h9BOigf8CXtljKYe6CrS8pjN5GZ0G4Ck5VOuFDx7E+7wl6HjW0EnIfZJJ+R5GO4N PgFC5QZ6B1Owa5cpdGcqRKoY17ZgkD6doR4DTvxdCUrquxRXYQIlOM9MtwGFhd1W NzfCPYvUokn9d/y76Arklbzo+pFcrGI1Bo4y78S4mz6JOfsg1+8DQsyrPRqwIIbs 4xTXIyOfSsQph8bBbkR/BZdy+z40qGNDzw0YQRIwvIcxWDQM1+Tim5uAuZLuEe7M V0giL+8RNDUFkBMCYwnlvtdnl/pUfcJ9QlWvSVJokUf3iWuDy1Gynj5Tau+/zzx0 Ch3k65pQs41XF6BKzS4lhttNnT6Rog== =Rtx1 -----END PGP SIGNATURE----- --cpvLTH7QU4gwfq3S--