From patchwork Thu Apr 22 08:14:52 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Claire Chang X-Patchwork-Id: 12217887 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=-18.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT 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 DCB06C43461 for ; Thu, 22 Apr 2021 08:15:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9BEB661426 for ; Thu, 22 Apr 2021 08:15:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235099AbhDVIPy (ORCPT ); Thu, 22 Apr 2021 04:15:54 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38224 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234773AbhDVIPx (ORCPT ); Thu, 22 Apr 2021 04:15:53 -0400 Received: from mail-pj1-x102b.google.com (mail-pj1-x102b.google.com [IPv6:2607:f8b0:4864:20::102b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 233D8C06138C for ; Thu, 22 Apr 2021 01:15:19 -0700 (PDT) Received: by mail-pj1-x102b.google.com with SMTP id f11-20020a17090a638bb02901524d3a3d48so539232pjj.3 for ; Thu, 22 Apr 2021 01:15:19 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=FvJrG6v4LzxdU4oF5EoFjO30pTB4A85M49SYo7WPBCw=; b=AMMWTSQCSdwHsUUdJCOC7YgUNrGXxRc8ufe8ShxXHlWgfWfBk0oS2HBubv7AQuSAMq M0urTLFpK7JN5/zRDUB5Fe/pClBUqpuo+IAb+avdRaxLPwR3C9WYDtIQPHvIq7nNv2DT 9Un/y51JxY/e6QYvwfJXjQ/aVxL0I13goxqlM= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=FvJrG6v4LzxdU4oF5EoFjO30pTB4A85M49SYo7WPBCw=; b=TrfHiOnTpx4NGLWUbpgX0CQoiKYj4Rgk5c7UZliZFMZDyOfm0BPojgSs4tl/Og7ZZJ JKn2mIAUC4gEIiCyvWD6h6Dn0/wcn105OkwR8sd09FEGLaZOrv0hNSctf193YBdxcGaB hepn9V9KafAjfU9NyMR6vZU/bJA+nBTF96YuwtpZYfS20J3Cg9fedNdDEWrVi6pGgATl P8d2Z+9Iqjq5BICLqjjFQ0A54i9I5NNuPKISMRfg6vVtjStMtf8Ngf/i1A7N4fcD2vMM jCCFw66AzZPGlCu+WAG16PiS4b0Rj1Y1zUix+gA6SjseyLQ6+EWT4IcoS47Cut5JxWT1 O09Q== X-Gm-Message-State: AOAM533Lq0AWDc04cnFZJ1ZKA+rkr+56TCRt9p3DGLytUwpvbRgwRhoR 8UeaaWIgwupWxhXytDf0KEfffA== X-Google-Smtp-Source: ABdhPJyk2JPTp3iko6u7v5EX3M6TzCT5gzjwwnFh5uBqfgtgyUVxzY91nyUWyB+4tQ6Gme84DA/b2g== X-Received: by 2002:a17:902:edd5:b029:e9:7477:5f0a with SMTP id q21-20020a170902edd5b02900e974775f0amr2141960plk.81.1619079318644; Thu, 22 Apr 2021 01:15:18 -0700 (PDT) Received: from localhost ([2401:fa00:1:10:1a8e:1bde:f79e:c302]) by smtp.gmail.com with UTF8SMTPSA id r1sm1538054pjo.26.2021.04.22.01.15.11 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 22 Apr 2021 01:15:18 -0700 (PDT) From: Claire Chang To: Joerg Roedel , Will Deacon , Frank Rowand , Konrad Rzeszutek Wilk , boris.ostrovsky@oracle.com, jgross@suse.com, Christoph Hellwig , Marek Szyprowski Cc: 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, tientzu@chromium.org, 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, nouveau@lists.freedesktop.org, rodrigo.vivi@intel.com, thomas.hellstrom@linux.intel.com Subject: [PATCH v5 00/16] Restricted DMA Date: Thu, 22 Apr 2021 16:14:52 +0800 Message-Id: <20210422081508.3942748-1-tientzu@chromium.org> X-Mailer: git-send-email 2.31.1.368.gbe11c130af-goog MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org 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 v5: Rebase on latest linux-next v4: - Fix spinlock bad magic - Use rmem->name for debugfs entry - Address the comments in v3 v3: Using only one reserved memory region for both streaming DMA and memory allocation. https://lore.kernel.org/patchwork/cover/1360992/ v2: Building on top of swiotlb. https://lore.kernel.org/patchwork/cover/1280705/ v1: Using dma_map_ops. https://lore.kernel.org/patchwork/cover/1271660/ Claire Chang (16): swiotlb: Fix the type of index swiotlb: Refactor swiotlb init functions swiotlb: Refactor swiotlb_create_debugfs swiotlb: Add DMA_RESTRICTED_POOL swiotlb: Add restricted DMA pool initialization swiotlb: Add a new get_io_tlb_mem getter swiotlb: Update is_swiotlb_buffer to add a struct device argument swiotlb: Update is_swiotlb_active to add a struct device argument swiotlb: Bounce data from/to restricted DMA pool if available swiotlb: Move alloc_size to find_slots swiotlb: Refactor swiotlb_tbl_unmap_single dma-direct: Add a new wrapper __dma_direct_free_pages() swiotlb: Add restricted DMA alloc/free support. dma-direct: Allocate memory from restricted DMA pool if available dt-bindings: of: Add restricted DMA pool of: Add plumbing for restricted DMA pool .../reserved-memory/reserved-memory.txt | 24 ++ drivers/gpu/drm/i915/gem/i915_gem_internal.c | 2 +- drivers/gpu/drm/nouveau/nouveau_ttm.c | 2 +- drivers/iommu/dma-iommu.c | 12 +- drivers/of/address.c | 25 ++ drivers/of/device.c | 3 + drivers/of/of_private.h | 5 + drivers/pci/xen-pcifront.c | 2 +- drivers/xen/swiotlb-xen.c | 2 +- include/linux/device.h | 4 + include/linux/swiotlb.h | 41 ++- kernel/dma/Kconfig | 14 + kernel/dma/direct.c | 57 +++-- kernel/dma/direct.h | 9 +- kernel/dma/swiotlb.c | 242 +++++++++++++----- 15 files changed, 347 insertions(+), 97 deletions(-)