From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751945AbdJTGoq (ORCPT ); Fri, 20 Oct 2017 02:44:46 -0400 Received: from smtp.nue.novell.com ([195.135.221.5]:55487 "EHLO smtp.nue.novell.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751014AbdJTGoo (ORCPT ); Fri, 20 Oct 2017 02:44:44 -0400 Date: Fri, 20 Oct 2017 14:44:31 +0800 From: joeyli To: David Howells Cc: linux-security-module@vger.kernel.org, gnomes@lxorguk.ukuu.org.uk, linux-efi@vger.kernel.org, matthew.garrett@nebula.com, gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org, jforbes@redhat.com Subject: Re: [PATCH 13/27] asus-wmi: Restrict debugfs interface when the kernel is locked down Message-ID: <20171020064431.GU3285@linux-l9pv.suse> References: <150842463163.7923.11081723749106843698.stgit@warthog.procyon.org.uk> <150842473184.7923.9538070958624850416.stgit@warthog.procyon.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <150842473184.7923.9538070958624850416.stgit@warthog.procyon.org.uk> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Oct 19, 2017 at 03:52:11PM +0100, David Howells wrote: > From: Matthew Garrett > > We have no way of validating what all of the Asus WMI methods do on a given > machine - and there's a risk that some will allow hardware state to be > manipulated in such a way that arbitrary code can be executed in the > kernel, circumventing module loading restrictions. Prevent that if the > kernel is locked down. > > Signed-off-by: Matthew Garrett > Signed-off-by: David Howells I have reviewed this patch. Please feel free to add: Reviewed-by: "Lee, Chun-Yi" Thanks! Joey Lee > cc: acpi4asus-user@lists.sourceforge.net > cc: platform-driver-x86@vger.kernel.org > --- > > drivers/platform/x86/asus-wmi.c | 9 +++++++++ > 1 file changed, 9 insertions(+) > > diff --git a/drivers/platform/x86/asus-wmi.c b/drivers/platform/x86/asus-wmi.c > index 48e1541dc8d4..ef5587469337 100644 > --- a/drivers/platform/x86/asus-wmi.c > +++ b/drivers/platform/x86/asus-wmi.c > @@ -1905,6 +1905,9 @@ static int show_dsts(struct seq_file *m, void *data) > int err; > u32 retval = -1; > > + if (kernel_is_locked_down("Asus WMI")) > + return -EPERM; > + > err = asus_wmi_get_devstate(asus, asus->debug.dev_id, &retval); > > if (err < 0) > @@ -1921,6 +1924,9 @@ static int show_devs(struct seq_file *m, void *data) > int err; > u32 retval = -1; > > + if (kernel_is_locked_down("Asus WMI")) > + return -EPERM; > + > err = asus_wmi_set_devstate(asus->debug.dev_id, asus->debug.ctrl_param, > &retval); > > @@ -1945,6 +1951,9 @@ static int show_call(struct seq_file *m, void *data) > union acpi_object *obj; > acpi_status status; > > + if (kernel_is_locked_down("Asus WMI")) > + return -EPERM; > + > status = wmi_evaluate_method(ASUS_WMI_MGMT_GUID, > 0, asus->debug.method_id, > &input, &output); > > -- > To unsubscribe from this list: send the line "unsubscribe linux-efi" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html