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 7E87DC48BE8 for ; Sat, 22 Jun 2019 23:59:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 563BC20862 for ; Sat, 22 Jun 2019 23:59:47 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="hdw3d9Tk" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726481AbfFVX7q (ORCPT ); Sat, 22 Jun 2019 19:59:46 -0400 Received: from mail-pl1-f193.google.com ([209.85.214.193]:36679 "EHLO mail-pl1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726460AbfFVX7q (ORCPT ); Sat, 22 Jun 2019 19:59:46 -0400 Received: by mail-pl1-f193.google.com with SMTP id k8so4811131plt.3 for ; Sat, 22 Jun 2019 16:59:45 -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=bgrPjW7Kb7wUUX+DYrIOPFY5PfDgfePLDwa4gYfP52s=; b=hdw3d9Tkc9CTEuLiBL+v1GlT08Ye3N3vWBXfp9XuasCNI4S9OWAU6zx9TF7hFJDjU0 QIg3GIqC6FN3TzNUEOMrDsWUObccrdJCTI4md9CDw6UjxoB65gOs/KVaBYVAzTfaoGiL Rq5S5gjb5GDHuNNLba1IbMH7ohCl2ajLwIsy4= 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=bgrPjW7Kb7wUUX+DYrIOPFY5PfDgfePLDwa4gYfP52s=; b=SpsMQXiOJET2w/7UfXyVzVCmikCOJryJVaBnYG/VJ5ATwgNnT0kjfJEuJS/38XcZ3k Q4A/qPl6CGKYGTabQ4sVy+AvZiTCltV14fVN9TeXRU5s4knpCjxR1bkVPh0RS+GlasqZ nKEuKGjrzfZxkGuwITGyvYfNztVe2sUAW/OInsDr9eg4o8hmOc7F/VPV64IrEuSoHzYS UHL4UmN2EhAcwYbEfYXj7/yOB+KaUylvyttjF7zIsMoNtsOI56x4ISxB05IRVu6Z6CTu Vmenkuwtf4rgSkSgH9tUfUjq4BRd5AymKrygwAjECOqysGJPROlthmAsQ6qjAuUYKzYV VkCg== X-Gm-Message-State: APjAAAWZJ0VRSizhan4cGWGNPASgIqB0D2VCSMjJ1vj44pR8vhzeLo6c DC0LamSbpHk9WNbk/xy15DuDuA== X-Google-Smtp-Source: APXvYqxLFdr+xtXxViVFj1IN/jBNDDj9LPM0uAcMBAdURV0Qzqbd67foxSaQjGo3StJksc55FRXPcw== X-Received: by 2002:a17:902:e65:: with SMTP id 92mr133083051plw.13.1561247985604; Sat, 22 Jun 2019 16:59:45 -0700 (PDT) Received: from www.outflux.net (smtp.outflux.net. [198.145.64.163]) by smtp.gmail.com with ESMTPSA id y14sm6218653pjr.13.2019.06.22.16.59.44 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Sat, 22 Jun 2019 16:59:44 -0700 (PDT) Date: Sat, 22 Jun 2019 16:59:44 -0700 From: Kees Cook To: Matthew Garrett Cc: jmorris@namei.org, linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org, linux-api@vger.kernel.org, Josh Boyer , David Howells , Matthew Garrett , Dave Young , linux-acpi@vger.kernel.org Subject: Re: [PATCH V34 15/29] acpi: Ignore acpi_rsdp kernel param when the kernel has been locked down Message-ID: <201906221659.A04260B5@keescook> References: <20190622000358.19895-1-matthewgarrett@google.com> <20190622000358.19895-16-matthewgarrett@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190622000358.19895-16-matthewgarrett@google.com> Sender: linux-acpi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org On Fri, Jun 21, 2019 at 05:03:44PM -0700, Matthew Garrett wrote: > From: Josh Boyer > > This option allows userspace to pass the RSDP address to the kernel, which > makes it possible for a user to modify the workings of hardware . Reject > the option when the kernel is locked down. > > Signed-off-by: Josh Boyer Reviewed-by: Kees Cook -Kees > Signed-off-by: David Howells > Signed-off-by: Matthew Garrett > cc: Dave Young > cc: linux-acpi@vger.kernel.org > --- > drivers/acpi/osl.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c > index f29e427d0d1d..60cda8a0f36b 100644 > --- a/drivers/acpi/osl.c > +++ b/drivers/acpi/osl.c > @@ -40,6 +40,7 @@ > #include > #include > #include > +#include > > #include > #include > @@ -194,7 +195,7 @@ acpi_physical_address __init acpi_os_get_root_pointer(void) > acpi_physical_address pa; > > #ifdef CONFIG_KEXEC > - if (acpi_rsdp) > + if (acpi_rsdp && !security_locked_down(LOCKDOWN_ACPI_TABLES)) > return acpi_rsdp; > #endif > pa = acpi_arch_get_root_pointer(); > -- > 2.22.0.410.gd8fdbe21b5-goog > -- Kees Cook