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=-0.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED 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 53EC8C433DF for ; Tue, 7 Jul 2020 14:10:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 23309206E2 for ; Tue, 7 Jul 2020 14:10:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1594131034; bh=fS6mwHW4Azmod0g4YK5OopksQeFsmgWg0DrLuXR70dU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=TbN4uNFZaawTzts0FInuhsUTH7pSJmyy3HGLT8RLLrFfwH/TgPZW+ST597IMfu5PI AUNvXfYoEHdg3T0r0h5pD8Fa5rwF0/TVI6GuUtshfwnI06B35ujS2Ju+M1yr2M2XEM rqMxyHkm+vipG0k7kp3PUybBNjg0+8A7aHVaLTIo= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726805AbgGGOKd (ORCPT ); Tue, 7 Jul 2020 10:10:33 -0400 Received: from mail.kernel.org ([198.145.29.99]:46936 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725944AbgGGOKd (ORCPT ); Tue, 7 Jul 2020 10:10:33 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (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 AF01A2064B; Tue, 7 Jul 2020 14:10:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1594131033; bh=fS6mwHW4Azmod0g4YK5OopksQeFsmgWg0DrLuXR70dU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=KJpsr+HTeXaS6bPz27rREoX4/rxysooNVSnSdp8xkVwHA1Aoh6PH033UAXtY7b2Un cJ40dmwHu/GLO0kNAV4SiCAAoV2AkVMRl+LP9+Co0/HZuSdpbjFP7HGUwEO6W3C2fl zZbVftnoZHdUlvtKVV3N2eqG70mZzR97lHP5Wwds= Date: Tue, 7 Jul 2020 16:10:31 +0200 From: Greg Kroah-Hartman To: Ard Biesheuvel Cc: Peter Jones , "# 3.4.x" Subject: Re: WTF: patch "[PATCH] efi: Make it possible to disable efivar_ssdt entirely" was seriously submitted to be applied to the 5.7-stable tree? Message-ID: <20200707141031.GD4064836@kroah.com> References: <1593422635243184@kroah.com> <20200629154844.GA512815@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org On Mon, Jun 29, 2020 at 08:30:21PM +0200, Ard Biesheuvel wrote: > On Mon, 29 Jun 2020 at 17:48, Greg Kroah-Hartman > wrote: > > > > On Mon, Jun 29, 2020 at 05:18:08PM +0200, Ard Biesheuvel wrote: > > > On Mon, 29 Jun 2020 at 11:32, wrote: > > > > > > > > The patch below was submitted to be applied to the 5.7-stable tree. > > > > > > > > I fail to see how this patch meets the stable kernel rules as found at > > > > Documentation/process/stable-kernel-rules.rst. > > > > > > > > I could be totally wrong, and if so, please respond to > > > > and let me know why this patch should be > > > > applied. Otherwise, it is now dropped from my patch queues, never to be > > > > seen again. > > > > > > > > > > Without this patch, there is no way to disable sideloading of SSDTs > > > via EFI variables, which is a security hole. The fact that this is not > > > governed by the existing ACPI_TABLE_UPGRADE Kconfig option was an > > > oversight, and so distros currently have this functionality enabled > > > inadvertently (although most of them have the lockdown check > > > incorporated as well) > > > > > > SSDTs can manipulate any memory (even kernel memory that has been > > > mapped read-only) by using SystemMemory OpRegions in _INI AML methods, > > > and setting an EFI variable once will make this persist across > > > reboots. > > > > All of this was not in the description of the patch at all, how were we > > supposed to know this? > > > > Good point. This patch was the result of same off-list discussion, so > it was obvious to those involved but not for anyone else. > > > And this really looks like a new feature now that you are supporting > > something that we previously could not do. To know that this is a "fix" > > is not obvious :( > > > > I'll go queue it up, but how far back should it go? > > > > The feature was added in v4.8, so as close as we can get to that please. Ok, got it applied back to 4.9 now, thanks. greg k-h