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=-17.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 C3083C49EA2 for ; Wed, 16 Jun 2021 12:08:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9BA046128B for ; Wed, 16 Jun 2021 12:08:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231856AbhFPMK6 (ORCPT ); Wed, 16 Jun 2021 08:10:58 -0400 Received: from mail.kernel.org ([198.145.29.99]:45412 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229456AbhFPMKz (ORCPT ); Wed, 16 Jun 2021 08:10:55 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id CD51A61245; Wed, 16 Jun 2021 12:08:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1623845329; bh=QlkI38WT3hL5S6bnBl68cYI3mNCvqwOg2BtN6RClOD8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=gNoqbf4BoEB+mMSkF0LbPACcE8hfdhWziBuc3On0yCSF1OPpARGrphJEZzi5R8zhj EQBk9eSasfJ21LDYEs5fQgad/5i5kQ4hvjwr2VzkCT5qsBkbBa2YuO73damjDS9tPT gEWv6ceU59Ud8WyKcV32BLXCIyoDzCKKiI1Qx1b1D7h7TGQnS6Yc8Hh4jwg0vvdXHU 1ESCA6NJ9d+xly0Ts4XCXJSqpVE+kwtWKvwUzczVJ12VkVaF8vrrLoIIMNmcUpnUot CLEWTlb2HNfBG1sx2OnHpHCbJjguomfMTK9NnEnMModJku7GBFKFrxYfN57naGCL26 kwPvkXDDNtLyg== Date: Wed, 16 Jun 2021 13:08:38 +0100 From: Will Deacon To: Claire Chang Cc: Rob Herring , mpe@ellerman.id.au, Joerg Roedel , Frank Rowand , Konrad Rzeszutek Wilk , boris.ostrovsky@oracle.com, jgross@suse.com, Christoph Hellwig , Marek Szyprowski , benh@kernel.crashing.org, paulus@samba.org, "list@263.net:IOMMU DRIVERS" , sstabellini@kernel.org, Robin Murphy , grant.likely@arm.com, xypron.glpk@gmx.de, Thierry Reding , mingo@kernel.org, bauerman@linux.ibm.com, peterz@infradead.org, Greg KH , Saravana Kannan , "Rafael J . Wysocki" , heikki.krogerus@linux.intel.com, Andy Shevchenko , Randy Dunlap , Dan Williams , Bartosz Golaszewski , linux-devicetree , lkml , linuxppc-dev@lists.ozlabs.org, xen-devel@lists.xenproject.org, Nicolas Boichat , Jim Quinlan , tfiga@chromium.org, bskeggs@redhat.com, bhelgaas@google.com, chris@chris-wilson.co.uk, daniel@ffwll.ch, airlied@linux.ie, dri-devel@lists.freedesktop.org, intel-gfx@lists.freedesktop.org, jani.nikula@linux.intel.com, jxgao@google.com, joonas.lahtinen@linux.intel.com, linux-pci@vger.kernel.org, maarten.lankhorst@linux.intel.com, matthew.auld@intel.com, rodrigo.vivi@intel.com, thomas.hellstrom@linux.intel.com Subject: Re: [PATCH v12 00/12] Restricted DMA Message-ID: <20210616120837.GA22783@willie-the-truck> References: <20210616062157.953777-1-tientzu@chromium.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210616062157.953777-1-tientzu@chromium.org> User-Agent: Mutt/1.10.1 (2018-07-13) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Claire, On Wed, Jun 16, 2021 at 02:21:45PM +0800, Claire Chang wrote: > This series implements mitigations for lack of DMA access control on > systems without an IOMMU, which could result in the DMA accessing the > system memory at unexpected times and/or unexpected addresses, possibly > leading to data leakage or corruption. > > For example, we plan to use the PCI-e bus for Wi-Fi and that PCI-e bus is > not behind an IOMMU. As PCI-e, by design, gives the device full access to > system memory, a vulnerability in the Wi-Fi firmware could easily escalate > to a full system exploit (remote wifi exploits: [1a], [1b] that shows a > full chain of exploits; [2], [3]). > > To mitigate the security concerns, we introduce restricted DMA. Restricted > DMA utilizes the existing swiotlb to bounce streaming DMA in and out of a > specially allocated region and does memory allocation from the same region. > The feature on its own provides a basic level of protection against the DMA > overwriting buffer contents at unexpected times. However, to protect > against general data leakage and system memory corruption, the system needs > to provide a way to restrict the DMA to a predefined memory region (this is > usually done at firmware level, e.g. MPU in ATF on some ARM platforms [4]). > > [1a] https://googleprojectzero.blogspot.com/2017/04/over-air-exploiting-broadcoms-wi-fi_4.html > [1b] https://googleprojectzero.blogspot.com/2017/04/over-air-exploiting-broadcoms-wi-fi_11.html > [2] https://blade.tencent.com/en/advisories/qualpwn/ > [3] https://www.bleepingcomputer.com/news/security/vulnerabilities-found-in-highly-popular-firmware-for-wifi-chips/ > [4] https://github.com/ARM-software/arm-trusted-firmware/blob/master/plat/mediatek/mt8183/drivers/emi_mpu/emi_mpu.c#L132 > > v12: > Split is_dev_swiotlb_force into is_swiotlb_force_bounce (patch 06/12) and > is_swiotlb_for_alloc (patch 09/12) I took this for a spin in an arm64 KVM guest with virtio devices using the DMA API and it works as expected on top of swiotlb devel/for-linus-5.14, so: Tested-by: Will Deacon Thanks! Will 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=-15.3 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,INCLUDES_CR_TRAILER,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 4B343C48BE5 for ; Wed, 16 Jun 2021 12:09:23 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 953C26115C for ; Wed, 16 Jun 2021 12:09:22 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 953C26115C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4G4kWP66gvz3c0d for ; Wed, 16 Jun 2021 22:09:21 +1000 (AEST) Authentication-Results: lists.ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20201202 header.b=gNoqbf4B; dkim-atps=neutral Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=kernel.org (client-ip=198.145.29.99; helo=mail.kernel.org; envelope-from=will@kernel.org; receiver=) Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20201202 header.b=gNoqbf4B; dkim-atps=neutral Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4G4kVs58b0z2ykR for ; Wed, 16 Jun 2021 22:08:53 +1000 (AEST) Received: by mail.kernel.org (Postfix) with ESMTPSA id CD51A61245; Wed, 16 Jun 2021 12:08:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1623845329; bh=QlkI38WT3hL5S6bnBl68cYI3mNCvqwOg2BtN6RClOD8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=gNoqbf4BoEB+mMSkF0LbPACcE8hfdhWziBuc3On0yCSF1OPpARGrphJEZzi5R8zhj EQBk9eSasfJ21LDYEs5fQgad/5i5kQ4hvjwr2VzkCT5qsBkbBa2YuO73damjDS9tPT gEWv6ceU59Ud8WyKcV32BLXCIyoDzCKKiI1Qx1b1D7h7TGQnS6Yc8Hh4jwg0vvdXHU 1ESCA6NJ9d+xly0Ts4XCXJSqpVE+kwtWKvwUzczVJ12VkVaF8vrrLoIIMNmcUpnUot CLEWTlb2HNfBG1sx2OnHpHCbJjguomfMTK9NnEnMModJku7GBFKFrxYfN57naGCL26 kwPvkXDDNtLyg== Date: Wed, 16 Jun 2021 13:08:38 +0100 From: Will Deacon To: Claire Chang Subject: Re: [PATCH v12 00/12] Restricted DMA Message-ID: <20210616120837.GA22783@willie-the-truck> References: <20210616062157.953777-1-tientzu@chromium.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210616062157.953777-1-tientzu@chromium.org> User-Agent: Mutt/1.10.1 (2018-07-13) X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: heikki.krogerus@linux.intel.com, thomas.hellstrom@linux.intel.com, peterz@infradead.org, joonas.lahtinen@linux.intel.com, dri-devel@lists.freedesktop.org, chris@chris-wilson.co.uk, grant.likely@arm.com, paulus@samba.org, Frank Rowand , mingo@kernel.org, Marek Szyprowski , sstabellini@kernel.org, Saravana Kannan , Joerg Roedel , "Rafael J . Wysocki" , Christoph Hellwig , Bartosz Golaszewski , bskeggs@redhat.com, linux-pci@vger.kernel.org, xen-devel@lists.xenproject.org, Thierry Reding , intel-gfx@lists.freedesktop.org, matthew.auld@intel.com, linux-devicetree , jxgao@google.com, daniel@ffwll.ch, Konrad Rzeszutek Wilk , maarten.lankhorst@linux.intel.com, airlied@linux.ie, Dan Williams , linuxppc-dev@lists.ozlabs.org, jani.nikula@linux.intel.com, Rob Herring , rodrigo.vivi@intel.com, bhelgaas@google.com, boris.ostrovsky@oracle.com, Andy Shevchenko , jgross@suse.com, Nicolas Boichat , Greg KH , Randy Dunlap , lkml , tfiga@chromium.org, "list@263.net:IOMMU DRIVERS" , Jim Quinlan , xypron.glpk@gmx.de, Robin Murphy , bauerman@linux.ibm.com Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" Hi Claire, On Wed, Jun 16, 2021 at 02:21:45PM +0800, Claire Chang wrote: > This series implements mitigations for lack of DMA access control on > systems without an IOMMU, which could result in the DMA accessing the > system memory at unexpected times and/or unexpected addresses, possibly > leading to data leakage or corruption. > > For example, we plan to use the PCI-e bus for Wi-Fi and that PCI-e bus is > not behind an IOMMU. As PCI-e, by design, gives the device full access to > system memory, a vulnerability in the Wi-Fi firmware could easily escalate > to a full system exploit (remote wifi exploits: [1a], [1b] that shows a > full chain of exploits; [2], [3]). > > To mitigate the security concerns, we introduce restricted DMA. Restricted > DMA utilizes the existing swiotlb to bounce streaming DMA in and out of a > specially allocated region and does memory allocation from the same region. > The feature on its own provides a basic level of protection against the DMA > overwriting buffer contents at unexpected times. However, to protect > against general data leakage and system memory corruption, the system needs > to provide a way to restrict the DMA to a predefined memory region (this is > usually done at firmware level, e.g. MPU in ATF on some ARM platforms [4]). > > [1a] https://googleprojectzero.blogspot.com/2017/04/over-air-exploiting-broadcoms-wi-fi_4.html > [1b] https://googleprojectzero.blogspot.com/2017/04/over-air-exploiting-broadcoms-wi-fi_11.html > [2] https://blade.tencent.com/en/advisories/qualpwn/ > [3] https://www.bleepingcomputer.com/news/security/vulnerabilities-found-in-highly-popular-firmware-for-wifi-chips/ > [4] https://github.com/ARM-software/arm-trusted-firmware/blob/master/plat/mediatek/mt8183/drivers/emi_mpu/emi_mpu.c#L132 > > v12: > Split is_dev_swiotlb_force into is_swiotlb_force_bounce (patch 06/12) and > is_swiotlb_for_alloc (patch 09/12) I took this for a spin in an arm64 KVM guest with virtio devices using the DMA API and it works as expected on top of swiotlb devel/for-linus-5.14, so: Tested-by: Will Deacon Thanks! Will 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=-15.3 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,INCLUDES_CR_TRAILER,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 305C7C48BE6 for ; Wed, 16 Jun 2021 12:08:54 +0000 (UTC) Received: from smtp4.osuosl.org (smtp4.osuosl.org [140.211.166.137]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id D77C8613D8 for ; Wed, 16 Jun 2021 12:08:53 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D77C8613D8 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=iommu-bounces@lists.linux-foundation.org Received: from localhost (localhost [127.0.0.1]) by smtp4.osuosl.org (Postfix) with ESMTP id 9EC0F40207; Wed, 16 Jun 2021 12:08:53 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp4.osuosl.org ([127.0.0.1]) by localhost (smtp4.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id iUWe5eEGhlXG; Wed, 16 Jun 2021 12:08:52 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [IPv6:2605:bc80:3010:104::8cd3:938]) by smtp4.osuosl.org (Postfix) with ESMTPS id 07376401E3; Wed, 16 Jun 2021 12:08:51 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id CAAEBC000D; Wed, 16 Jun 2021 12:08:51 +0000 (UTC) Received: from smtp1.osuosl.org (smtp1.osuosl.org [140.211.166.138]) by lists.linuxfoundation.org (Postfix) with ESMTP id F25E0C000B for ; Wed, 16 Jun 2021 12:08:50 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp1.osuosl.org (Postfix) with ESMTP id D2E9D82F40 for ; Wed, 16 Jun 2021 12:08:50 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Authentication-Results: smtp1.osuosl.org (amavisd-new); dkim=pass (2048-bit key) header.d=kernel.org Received: from smtp1.osuosl.org ([127.0.0.1]) by localhost (smtp1.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id oj2QeHEkbC4Q for ; Wed, 16 Jun 2021 12:08:50 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.8.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp1.osuosl.org (Postfix) with ESMTPS id 0E9F382EBA for ; Wed, 16 Jun 2021 12:08:49 +0000 (UTC) Received: by mail.kernel.org (Postfix) with ESMTPSA id CD51A61245; Wed, 16 Jun 2021 12:08:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1623845329; bh=QlkI38WT3hL5S6bnBl68cYI3mNCvqwOg2BtN6RClOD8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=gNoqbf4BoEB+mMSkF0LbPACcE8hfdhWziBuc3On0yCSF1OPpARGrphJEZzi5R8zhj EQBk9eSasfJ21LDYEs5fQgad/5i5kQ4hvjwr2VzkCT5qsBkbBa2YuO73damjDS9tPT gEWv6ceU59Ud8WyKcV32BLXCIyoDzCKKiI1Qx1b1D7h7TGQnS6Yc8Hh4jwg0vvdXHU 1ESCA6NJ9d+xly0Ts4XCXJSqpVE+kwtWKvwUzczVJ12VkVaF8vrrLoIIMNmcUpnUot CLEWTlb2HNfBG1sx2OnHpHCbJjguomfMTK9NnEnMModJku7GBFKFrxYfN57naGCL26 kwPvkXDDNtLyg== Date: Wed, 16 Jun 2021 13:08:38 +0100 From: Will Deacon To: Claire Chang Subject: Re: [PATCH v12 00/12] Restricted DMA Message-ID: <20210616120837.GA22783@willie-the-truck> References: <20210616062157.953777-1-tientzu@chromium.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20210616062157.953777-1-tientzu@chromium.org> User-Agent: Mutt/1.10.1 (2018-07-13) Cc: heikki.krogerus@linux.intel.com, thomas.hellstrom@linux.intel.com, peterz@infradead.org, benh@kernel.crashing.org, joonas.lahtinen@linux.intel.com, dri-devel@lists.freedesktop.org, chris@chris-wilson.co.uk, grant.likely@arm.com, paulus@samba.org, Frank Rowand , mingo@kernel.org, sstabellini@kernel.org, Saravana Kannan , mpe@ellerman.id.au, "Rafael J . Wysocki" , Christoph Hellwig , Bartosz Golaszewski , bskeggs@redhat.com, linux-pci@vger.kernel.org, xen-devel@lists.xenproject.org, Thierry Reding , intel-gfx@lists.freedesktop.org, matthew.auld@intel.com, linux-devicetree , jxgao@google.com, daniel@ffwll.ch, Konrad Rzeszutek Wilk , maarten.lankhorst@linux.intel.com, airlied@linux.ie, Dan Williams , linuxppc-dev@lists.ozlabs.org, jani.nikula@linux.intel.com, Rob Herring , rodrigo.vivi@intel.com, bhelgaas@google.com, boris.ostrovsky@oracle.com, Andy Shevchenko , jgross@suse.com, Nicolas Boichat , Greg KH , Randy Dunlap , lkml , "list@263.net:IOMMU DRIVERS" , Jim Quinlan , xypron.glpk@gmx.de, Robin Murphy , bauerman@linux.ibm.com X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: iommu-bounces@lists.linux-foundation.org Sender: "iommu" Hi Claire, On Wed, Jun 16, 2021 at 02:21:45PM +0800, Claire Chang wrote: > This series implements mitigations for lack of DMA access control on > systems without an IOMMU, which could result in the DMA accessing the > system memory at unexpected times and/or unexpected addresses, possibly > leading to data leakage or corruption. > > For example, we plan to use the PCI-e bus for Wi-Fi and that PCI-e bus is > not behind an IOMMU. As PCI-e, by design, gives the device full access to > system memory, a vulnerability in the Wi-Fi firmware could easily escalate > to a full system exploit (remote wifi exploits: [1a], [1b] that shows a > full chain of exploits; [2], [3]). > > To mitigate the security concerns, we introduce restricted DMA. Restricted > DMA utilizes the existing swiotlb to bounce streaming DMA in and out of a > specially allocated region and does memory allocation from the same region. > The feature on its own provides a basic level of protection against the DMA > overwriting buffer contents at unexpected times. However, to protect > against general data leakage and system memory corruption, the system needs > to provide a way to restrict the DMA to a predefined memory region (this is > usually done at firmware level, e.g. MPU in ATF on some ARM platforms [4]). > > [1a] https://googleprojectzero.blogspot.com/2017/04/over-air-exploiting-broadcoms-wi-fi_4.html > [1b] https://googleprojectzero.blogspot.com/2017/04/over-air-exploiting-broadcoms-wi-fi_11.html > [2] https://blade.tencent.com/en/advisories/qualpwn/ > [3] https://www.bleepingcomputer.com/news/security/vulnerabilities-found-in-highly-popular-firmware-for-wifi-chips/ > [4] https://github.com/ARM-software/arm-trusted-firmware/blob/master/plat/mediatek/mt8183/drivers/emi_mpu/emi_mpu.c#L132 > > v12: > Split is_dev_swiotlb_force into is_swiotlb_force_bounce (patch 06/12) and > is_swiotlb_for_alloc (patch 09/12) I took this for a spin in an arm64 KVM guest with virtio devices using the DMA API and it works as expected on top of swiotlb devel/for-linus-5.14, so: Tested-by: Will Deacon Thanks! Will _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu 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=-15.3 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,INCLUDES_CR_TRAILER,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham 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 7D021C48BE6 for ; Wed, 16 Jun 2021 12:08:51 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 2C3766128C for ; Wed, 16 Jun 2021 12:08:51 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2C3766128C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 97D2989838; Wed, 16 Jun 2021 12:08:50 +0000 (UTC) Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by gabe.freedesktop.org (Postfix) with ESMTPS id B8D0689838; Wed, 16 Jun 2021 12:08:49 +0000 (UTC) Received: by mail.kernel.org (Postfix) with ESMTPSA id CD51A61245; Wed, 16 Jun 2021 12:08:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1623845329; bh=QlkI38WT3hL5S6bnBl68cYI3mNCvqwOg2BtN6RClOD8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=gNoqbf4BoEB+mMSkF0LbPACcE8hfdhWziBuc3On0yCSF1OPpARGrphJEZzi5R8zhj EQBk9eSasfJ21LDYEs5fQgad/5i5kQ4hvjwr2VzkCT5qsBkbBa2YuO73damjDS9tPT gEWv6ceU59Ud8WyKcV32BLXCIyoDzCKKiI1Qx1b1D7h7TGQnS6Yc8Hh4jwg0vvdXHU 1ESCA6NJ9d+xly0Ts4XCXJSqpVE+kwtWKvwUzczVJ12VkVaF8vrrLoIIMNmcUpnUot CLEWTlb2HNfBG1sx2OnHpHCbJjguomfMTK9NnEnMModJku7GBFKFrxYfN57naGCL26 kwPvkXDDNtLyg== Date: Wed, 16 Jun 2021 13:08:38 +0100 From: Will Deacon To: Claire Chang Subject: Re: [PATCH v12 00/12] Restricted DMA Message-ID: <20210616120837.GA22783@willie-the-truck> References: <20210616062157.953777-1-tientzu@chromium.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210616062157.953777-1-tientzu@chromium.org> User-Agent: Mutt/1.10.1 (2018-07-13) X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: heikki.krogerus@linux.intel.com, thomas.hellstrom@linux.intel.com, peterz@infradead.org, dri-devel@lists.freedesktop.org, chris@chris-wilson.co.uk, grant.likely@arm.com, paulus@samba.org, Frank Rowand , mingo@kernel.org, Marek Szyprowski , sstabellini@kernel.org, Saravana Kannan , mpe@ellerman.id.au, Joerg Roedel , "Rafael J . Wysocki" , Christoph Hellwig , Bartosz Golaszewski , bskeggs@redhat.com, linux-pci@vger.kernel.org, xen-devel@lists.xenproject.org, Thierry Reding , intel-gfx@lists.freedesktop.org, matthew.auld@intel.com, linux-devicetree , jxgao@google.com, Konrad Rzeszutek Wilk , airlied@linux.ie, Dan Williams , linuxppc-dev@lists.ozlabs.org, Rob Herring , rodrigo.vivi@intel.com, bhelgaas@google.com, boris.ostrovsky@oracle.com, Andy Shevchenko , jgross@suse.com, Nicolas Boichat , Greg KH , Randy Dunlap , lkml , tfiga@chromium.org, "list@263.net:IOMMU DRIVERS" , Jim Quinlan , xypron.glpk@gmx.de, Robin Murphy , bauerman@linux.ibm.com Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Hi Claire, On Wed, Jun 16, 2021 at 02:21:45PM +0800, Claire Chang wrote: > This series implements mitigations for lack of DMA access control on > systems without an IOMMU, which could result in the DMA accessing the > system memory at unexpected times and/or unexpected addresses, possibly > leading to data leakage or corruption. > > For example, we plan to use the PCI-e bus for Wi-Fi and that PCI-e bus is > not behind an IOMMU. As PCI-e, by design, gives the device full access to > system memory, a vulnerability in the Wi-Fi firmware could easily escalate > to a full system exploit (remote wifi exploits: [1a], [1b] that shows a > full chain of exploits; [2], [3]). > > To mitigate the security concerns, we introduce restricted DMA. Restricted > DMA utilizes the existing swiotlb to bounce streaming DMA in and out of a > specially allocated region and does memory allocation from the same region. > The feature on its own provides a basic level of protection against the DMA > overwriting buffer contents at unexpected times. However, to protect > against general data leakage and system memory corruption, the system needs > to provide a way to restrict the DMA to a predefined memory region (this is > usually done at firmware level, e.g. MPU in ATF on some ARM platforms [4]). > > [1a] https://googleprojectzero.blogspot.com/2017/04/over-air-exploiting-broadcoms-wi-fi_4.html > [1b] https://googleprojectzero.blogspot.com/2017/04/over-air-exploiting-broadcoms-wi-fi_11.html > [2] https://blade.tencent.com/en/advisories/qualpwn/ > [3] https://www.bleepingcomputer.com/news/security/vulnerabilities-found-in-highly-popular-firmware-for-wifi-chips/ > [4] https://github.com/ARM-software/arm-trusted-firmware/blob/master/plat/mediatek/mt8183/drivers/emi_mpu/emi_mpu.c#L132 > > v12: > Split is_dev_swiotlb_force into is_swiotlb_force_bounce (patch 06/12) and > is_swiotlb_for_alloc (patch 09/12) I took this for a spin in an arm64 KVM guest with virtio devices using the DMA API and it works as expected on top of swiotlb devel/for-linus-5.14, so: Tested-by: Will Deacon Thanks! Will 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=-15.3 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,INCLUDES_CR_TRAILER,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 81072C48BE5 for ; Wed, 16 Jun 2021 12:12:11 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 355B46128B for ; Wed, 16 Jun 2021 12:12:11 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 355B46128B Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=intel-gfx-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 879B76E02D; Wed, 16 Jun 2021 12:12:10 +0000 (UTC) Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by gabe.freedesktop.org (Postfix) with ESMTPS id B8D0689838; Wed, 16 Jun 2021 12:08:49 +0000 (UTC) Received: by mail.kernel.org (Postfix) with ESMTPSA id CD51A61245; Wed, 16 Jun 2021 12:08:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1623845329; bh=QlkI38WT3hL5S6bnBl68cYI3mNCvqwOg2BtN6RClOD8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=gNoqbf4BoEB+mMSkF0LbPACcE8hfdhWziBuc3On0yCSF1OPpARGrphJEZzi5R8zhj EQBk9eSasfJ21LDYEs5fQgad/5i5kQ4hvjwr2VzkCT5qsBkbBa2YuO73damjDS9tPT gEWv6ceU59Ud8WyKcV32BLXCIyoDzCKKiI1Qx1b1D7h7TGQnS6Yc8Hh4jwg0vvdXHU 1ESCA6NJ9d+xly0Ts4XCXJSqpVE+kwtWKvwUzczVJ12VkVaF8vrrLoIIMNmcUpnUot CLEWTlb2HNfBG1sx2OnHpHCbJjguomfMTK9NnEnMModJku7GBFKFrxYfN57naGCL26 kwPvkXDDNtLyg== Date: Wed, 16 Jun 2021 13:08:38 +0100 From: Will Deacon To: Claire Chang Message-ID: <20210616120837.GA22783@willie-the-truck> References: <20210616062157.953777-1-tientzu@chromium.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20210616062157.953777-1-tientzu@chromium.org> User-Agent: Mutt/1.10.1 (2018-07-13) X-Mailman-Approved-At: Wed, 16 Jun 2021 12:12:09 +0000 Subject: Re: [Intel-gfx] [PATCH v12 00/12] Restricted DMA X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: heikki.krogerus@linux.intel.com, thomas.hellstrom@linux.intel.com, peterz@infradead.org, benh@kernel.crashing.org, dri-devel@lists.freedesktop.org, chris@chris-wilson.co.uk, grant.likely@arm.com, paulus@samba.org, Frank Rowand , mingo@kernel.org, Marek Szyprowski , sstabellini@kernel.org, Saravana Kannan , mpe@ellerman.id.au, Joerg Roedel , "Rafael J . Wysocki" , Christoph Hellwig , Bartosz Golaszewski , bskeggs@redhat.com, linux-pci@vger.kernel.org, xen-devel@lists.xenproject.org, Thierry Reding , intel-gfx@lists.freedesktop.org, matthew.auld@intel.com, linux-devicetree , jxgao@google.com, Konrad Rzeszutek Wilk , airlied@linux.ie, Dan Williams , linuxppc-dev@lists.ozlabs.org, Rob Herring , bhelgaas@google.com, boris.ostrovsky@oracle.com, Andy Shevchenko , jgross@suse.com, Nicolas Boichat , Greg KH , Randy Dunlap , lkml , tfiga@chromium.org, "list@263.net:IOMMU DRIVERS" , Jim Quinlan , xypron.glpk@gmx.de, Robin Murphy , bauerman@linux.ibm.com Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" Hi Claire, On Wed, Jun 16, 2021 at 02:21:45PM +0800, Claire Chang wrote: > This series implements mitigations for lack of DMA access control on > systems without an IOMMU, which could result in the DMA accessing the > system memory at unexpected times and/or unexpected addresses, possibly > leading to data leakage or corruption. > > For example, we plan to use the PCI-e bus for Wi-Fi and that PCI-e bus is > not behind an IOMMU. As PCI-e, by design, gives the device full access to > system memory, a vulnerability in the Wi-Fi firmware could easily escalate > to a full system exploit (remote wifi exploits: [1a], [1b] that shows a > full chain of exploits; [2], [3]). > > To mitigate the security concerns, we introduce restricted DMA. Restricted > DMA utilizes the existing swiotlb to bounce streaming DMA in and out of a > specially allocated region and does memory allocation from the same region. > The feature on its own provides a basic level of protection against the DMA > overwriting buffer contents at unexpected times. However, to protect > against general data leakage and system memory corruption, the system needs > to provide a way to restrict the DMA to a predefined memory region (this is > usually done at firmware level, e.g. MPU in ATF on some ARM platforms [4]). > > [1a] https://googleprojectzero.blogspot.com/2017/04/over-air-exploiting-broadcoms-wi-fi_4.html > [1b] https://googleprojectzero.blogspot.com/2017/04/over-air-exploiting-broadcoms-wi-fi_11.html > [2] https://blade.tencent.com/en/advisories/qualpwn/ > [3] https://www.bleepingcomputer.com/news/security/vulnerabilities-found-in-highly-popular-firmware-for-wifi-chips/ > [4] https://github.com/ARM-software/arm-trusted-firmware/blob/master/plat/mediatek/mt8183/drivers/emi_mpu/emi_mpu.c#L132 > > v12: > Split is_dev_swiotlb_force into is_swiotlb_force_bounce (patch 06/12) and > is_swiotlb_for_alloc (patch 09/12) I took this for a spin in an arm64 KVM guest with virtio devices using the DMA API and it works as expected on top of swiotlb devel/for-linus-5.14, so: Tested-by: Will Deacon Thanks! Will _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx