Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759571AbcLANub (ORCPT ); Thu, 1 Dec 2016 08:50:31 -0500 Received: from mail-yw0-f196.google.com ([209.85.161.196]:36144 "EHLO mail-yw0-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759436AbcLANu2 (ORCPT ); Thu, 1 Dec 2016 08:50:28 -0500 Date: Thu, 1 Dec 2016 08:50:25 -0500 From: William Breathitt Gray To: David Howells Cc: linux-kernel@vger.kernel.org, gnomes@lxorguk.ukuu.org.uk, minyard@acm.org, linux-iio@vger.kernel.org, linux-security-module@vger.kernel.org, keyrings@vger.kernel.org, Jonathan Cameron Subject: Re: [PATCH 10/39] Annotate hardware config module parameters in drivers/iio/ Message-ID: <20161201135025.GB30135@sophia> References: <148059537897.31612.9461043954611464597.stgit@warthog.procyon.org.uk> <148059545558.31612.1279403857733187213.stgit@warthog.procyon.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <148059545558.31612.1279403857733187213.stgit@warthog.procyon.org.uk> User-Agent: Mutt/1.7.1 (2016-10-04) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2537 Lines: 62 On Thu, Dec 01, 2016 at 12:30:55PM +0000, David Howells wrote: >When the kernel is running in secure boot mode, we lock down the kernel to >prevent userspace from modifying the running kernel image. Whilst this >includes prohibiting access to things like /dev/mem, it must also prevent >access by means of configuring driver modules in such a way as to cause a >device to access or modify the kernel image. > >To this end, annotate module_param* statements that refer to hardware >configuration and indicate for future reference what type of parameter they >specify. The parameter parser in the core sees this information and can >skip such parameters with an error message if the kernel is locked down. >The module initialisation then runs as normal, but just sees whatever the >default values for those parameters is. > >Note that we do still need to do the module initialisation because some >drivers have viable defaults set in case parameters aren't specified and >some drivers support automatic configuration (e.g. PNP or PCI) in addition >to manually coded parameters. > >This patch annotates drivers in drivers/iio/. > >Suggested-by: One Thousand Gnomes >Signed-off-by: David Howells >cc: William Breathitt Gray >cc: Jonathan Cameron >cc: linux-iio@vger.kernel.org Acked-by: William Breathitt Gray >--- > > drivers/iio/adc/stx104.c | 2 +- > drivers/iio/dac/cio-dac.c | 2 +- > 2 files changed, 2 insertions(+), 2 deletions(-) > >diff --git a/drivers/iio/adc/stx104.c b/drivers/iio/adc/stx104.c >index 7e3645749eaf..a805bd543acb 100644 >--- a/drivers/iio/adc/stx104.c >+++ b/drivers/iio/adc/stx104.c >@@ -49,7 +49,7 @@ > > static unsigned int base[max_num_isa_dev(STX104_EXTENT)]; > static unsigned int num_stx104; >-module_param_array(base, uint, &num_stx104, 0); >+module_param_hw_array(base, uint, ioport, &num_stx104, 0); > MODULE_PARM_DESC(base, "Apex Embedded Systems STX104 base addresses"); > > /** >diff --git a/drivers/iio/dac/cio-dac.c b/drivers/iio/dac/cio-dac.c >index 5a743e2a779d..dac086129edf 100644 >--- a/drivers/iio/dac/cio-dac.c >+++ b/drivers/iio/dac/cio-dac.c >@@ -39,7 +39,7 @@ > > static unsigned int base[max_num_isa_dev(CIO_DAC_EXTENT)]; > static unsigned int num_cio_dac; >-module_param_array(base, uint, &num_cio_dac, 0); >+module_param_hw_array(base, uint, ioport, &num_cio_dac, 0); > MODULE_PARM_DESC(base, "Measurement Computing CIO-DAC base addresses"); > > /** >