From patchwork Mon May 10 09:50:11 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Claire Chang X-Patchwork-Id: 12247367 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=-19.4 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 757AFC433B4 for ; Mon, 10 May 2021 09:50:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 52D8D610CC for ; Mon, 10 May 2021 09:50:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230254AbhEJJvp (ORCPT ); Mon, 10 May 2021 05:51:45 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57838 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230383AbhEJJvo (ORCPT ); Mon, 10 May 2021 05:51:44 -0400 Received: from mail-pg1-x52d.google.com (mail-pg1-x52d.google.com [IPv6:2607:f8b0:4864:20::52d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1BC6AC061761 for ; Mon, 10 May 2021 02:50:40 -0700 (PDT) Received: by mail-pg1-x52d.google.com with SMTP id m37so12899409pgb.8 for ; Mon, 10 May 2021 02:50:40 -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=suql6mxhF7VWacBQX+vVI90y4jo7pK7o7lRK42P1ziE=; b=lOHb/wGLPI35HYDpC1OybPS0wSHtEceWE9NWy4yGK8ilXXldfGkKtOa8K66bNr4LEO Pr9azSla0OuJEaDOigJpQisql/QT6Rzgq/OL94Z5dEW4Jo9qDvVnUfwuUeDl/NGvpzhn KxdIcdeNTo8YF1ZknPwF9akS+XlqzfXmq6cBU= 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=suql6mxhF7VWacBQX+vVI90y4jo7pK7o7lRK42P1ziE=; b=G3G4oXrHkP2wWcNmyUPPEV8XKRKqU/pFTFD6AOVGe3tyqt1IL3QEguwSzKRp49Bbzw /dvdluAJo/tvkwFM3MIjpLXJMJ2aKPFdAMxrUfI/Wev7+vTL8MrJE6WoJcPvKQO0DPz1 s6csM9cd/PpWZ+yoUxi3F4NSA51lw13oUo5VofLE1lM4S2PbRDyGZF2lTL2Xm7hOwAc+ fY1pY4SJFYYf24zOs7BKrt0h643cxQvkDEKPbEhVaPliTmU2ojCUFZdl7ivGf/qoIxAV 2IWhDMBNWUhHio4si2tVktlFolRwjstgUcbgW9eJOiVm/wEurvKMPpp5VGgs0/Nj+P+b JDPQ== X-Gm-Message-State: AOAM5315YT0TVz/YtgojfFhfXDuayKaA+T0yq6z4+NE7sVVazJeS8fj3 +GgGfet0Q0Oniu3Akz43sb4dmQ== X-Google-Smtp-Source: ABdhPJxaRNqwofbH1Q1gT6hjDo7UCjX7KCvjB0rJLaDOY22mJQZwGH/owOzO7oGoIZrGlaECEV1xwQ== X-Received: by 2002:a62:2a14:0:b029:263:20c5:6d8c with SMTP id q20-20020a622a140000b029026320c56d8cmr24491637pfq.23.1620640239613; Mon, 10 May 2021 02:50:39 -0700 (PDT) Received: from localhost ([2401:fa00:95:205:a524:abe8:94e3:5601]) by smtp.gmail.com with UTF8SMTPSA id 3sm10134744pff.132.2021.05.10.02.50.32 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 10 May 2021 02:50:39 -0700 (PDT) From: Claire Chang To: Rob Herring , mpe@ellerman.id.au, 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, Claire Chang Subject: [PATCH v6 00/15] Restricted DMA Date: Mon, 10 May 2021 17:50:11 +0800 Message-Id: <20210510095026.3477496-1-tientzu@chromium.org> X-Mailer: git-send-email 2.31.1.607.g51e8a6a459-goog MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org From: Claire Chang 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 v6: Address the comments in v5 v5: Rebase on latest linux-next https://lore.kernel.org/patchwork/cover/1416899/ v4: - Fix spinlock bad magic - Use rmem->name for debugfs entry - Address the comments in v3 https://lore.kernel.org/patchwork/cover/1378113/ 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/ *** BLURB HERE *** Claire Chang (15): 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 | 27 ++ 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 | 63 +++-- kernel/dma/direct.h | 9 +- kernel/dma/swiotlb.c | 242 +++++++++++++----- 15 files changed, 356 insertions(+), 97 deletions(-)