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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable 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 14335C48BD9 for ; Thu, 27 Jun 2019 17:26:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E387B2064A for ; Thu, 27 Jun 2019 17:26:14 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="M4aPeAy3" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726578AbfF0R0N (ORCPT ); Thu, 27 Jun 2019 13:26:13 -0400 Received: from mail-pf1-f194.google.com ([209.85.210.194]:33272 "EHLO mail-pf1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726315AbfF0R0N (ORCPT ); Thu, 27 Jun 2019 13:26:13 -0400 Received: by mail-pf1-f194.google.com with SMTP id x15so1578228pfq.0 for ; Thu, 27 Jun 2019 10:26:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=yC2k06ZrEbrPsihnFyfnuoaYxoQZIAB/UpnmdloBBeM=; b=M4aPeAy351r9m7DiPtmkWbyW8Ee0+gq/RD1Lg9wqwC8OOoQUCONycYei3PscpDyOhk OkKPaUedgsFtCO1shdwjpN4h163e76jNh/Co8Wn7gl19QplRZcMrhqfV5KsibtyZlnn4 hPQtpynZ7mgK5bBWvSUIRosOTKb186+XC2IUI= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=yC2k06ZrEbrPsihnFyfnuoaYxoQZIAB/UpnmdloBBeM=; b=qwOE4K/CNFJVOC+FDkZMFZtVpT7XZnsFl1rjoW/+tjI4c6HT8/SJIvnOVAKVE+ldEM Dar3RopCiUk/igfPOFie0aBkWSGE6uz53XbD3545tzg4tHFzFF3TCLtdHpoRnXeXkLsT ynibTYdQw/HWL0jAg3GHOlR7eeKZOJreNU16NWnVho2z5lpE3Xlil82yXJsqH8kQ6Mep +bwV6Nc6MVQjwT3NumzVlYeK3S+AG8c835+MY5SBmPtITdOaGN7fK7aVdhdA+etlTG+G gy3+KMKoPPOCkLYAiYuur4DBRlZ3Q9f0wK+7sQYQsn2taO6SVD47e/WZ9yJt6p6V3jpb csGQ== X-Gm-Message-State: APjAAAW75NohxJIqgG7Z1owFDbDeu22Iw3VEcNAxZdYbbaAHqvjFQ5qk vb+5RJqTLjCcwi2IPyLhZDU88g== X-Google-Smtp-Source: APXvYqwf1jdzj0nrLT8fzBbcq9r+JxRpv7xWxbAyaYhGiAa9jeVaHMzeWiFPuJE8tePBzv+dt30lhA== X-Received: by 2002:a17:90a:26ef:: with SMTP id m102mr7318879pje.50.1561656372771; Thu, 27 Jun 2019 10:26:12 -0700 (PDT) Received: from www.outflux.net (smtp.outflux.net. [198.145.64.163]) by smtp.gmail.com with ESMTPSA id h18sm4658023pfr.75.2019.06.27.10.26.11 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Thu, 27 Jun 2019 10:26:12 -0700 (PDT) Date: Thu, 27 Jun 2019 10:26:11 -0700 From: Kees Cook To: Andy Lutomirski Cc: x86@kernel.org, LKML , Florian Weimer , Jann Horn , stable@vger.kernel.org, Borislav Petkov , Kernel Hardening , Peter Zijlstra , Thomas Gleixner Subject: Re: [PATCH v2 1/8] x86/vsyscall: Remove the vsyscall=native documentation Message-ID: <201906271026.6AB1D9493@keescook> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jun 26, 2019 at 09:45:02PM -0700, Andy Lutomirski wrote: > The vsyscall=native feature is gone -- remove the docs. > > Fixes: 076ca272a14c ("x86/vsyscall/64: Drop "native" vsyscalls") > Cc: stable@vger.kernel.org > Cc: Kees Cook > Cc: Borislav Petkov > Cc: Kernel Hardening > Cc: Peter Zijlstra > Cc: Thomas Gleixner > Signed-off-by: Andy Lutomirski Acked-by: Kees Cook -Kees > --- > Documentation/admin-guide/kernel-parameters.txt | 6 ------ > 1 file changed, 6 deletions(-) > > diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt > index 138f6664b2e2..0082d1e56999 100644 > --- a/Documentation/admin-guide/kernel-parameters.txt > +++ b/Documentation/admin-guide/kernel-parameters.txt > @@ -5102,12 +5102,6 @@ > emulate [default] Vsyscalls turn into traps and are > emulated reasonably safely. > > - native Vsyscalls are native syscall instructions. > - This is a little bit faster than trapping > - and makes a few dynamic recompilers work > - better than they would in emulation mode. > - It also makes exploits much easier to write. > - > none Vsyscalls don't work at all. This makes > them quite hard to use for exploits but > might break your system. > -- > 2.21.0 > -- Kees Cook