From patchwork Fri Jun 11 15:26:45 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Claire Chang X-Patchwork-Id: 12315965 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=-18.9 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 8CFFBC48BE6 for ; Fri, 11 Jun 2021 15:28:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 79E8F61403 for ; Fri, 11 Jun 2021 15:28:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231861AbhFKPad (ORCPT ); Fri, 11 Jun 2021 11:30:33 -0400 Received: from mail-pf1-f175.google.com ([209.85.210.175]:44928 "EHLO mail-pf1-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231722AbhFKPaW (ORCPT ); Fri, 11 Jun 2021 11:30:22 -0400 Received: by mail-pf1-f175.google.com with SMTP id u18so4707375pfk.11 for ; Fri, 11 Jun 2021 08:28:12 -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=HzdTumh9BrSYWktV5WZf7y51LbAaw3C3h39TEtEC61A=; b=glnoPPl5BjuEU+aHwo6DAiEerdZdwKnsli+A2zYzDPxEZiqMUG0n7GdfkjKsK9QW0e 93P4fACu9M1YhL7kJ17IJaADBozzkAYJ7IX93Y7kPx7ZOfCFV+3jbYHpDWgy2cTfANYo 0mhxwlPjX1zbtnhLTHogjuk/5yAGZZVOgaVh4= 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=HzdTumh9BrSYWktV5WZf7y51LbAaw3C3h39TEtEC61A=; b=ooGB3aM3h/e3t4b2jYJBmnl2EkKal4LQYPfBg1QU33KADfPCWG6zyOyG+GMeQizhHR KZB8cg9qxZt7XXSsQFd/V1Es6xf5zSKLsgdFp04ZEzYFDPhNArETQILrlayuDjxra7fA HoajWn9QK7gLf3ZPthw/YupSNYtE8x+dvjTaUZkH44SO01EA/t+d+cV0InvRFRdMPbDJ y19J6uMxwSmuuCyX2NZNC1brtYC4aWpRM5w7VaUd6aZjMcvGdD/0rE9D2DzRffOIprnA Ai46K9u2cyc1iAi0cNXayTwHbEZVYBxDpFObmHzNBREh/8kLeg/Jv//5U/TNxeCzF57D RC/w== X-Gm-Message-State: AOAM532CDGxDp6IYuNSyyB9irgufS+/q3MM8jqZPrnN2BXHmi3Ux/kYR bkERgEorv4yOKrm4xl9LBPCyvg== X-Google-Smtp-Source: ABdhPJz1S7kolJJDhDCqvr+nlVhh2CsYK+ut0dTmzSatQWDsZRkoRFJesVPfEDUsaDthsVEt0zyWaw== X-Received: by 2002:aa7:828f:0:b029:200:6e27:8c8f with SMTP id s15-20020aa7828f0000b02902006e278c8fmr8819226pfm.44.1623425232214; Fri, 11 Jun 2021 08:27:12 -0700 (PDT) Received: from localhost ([2401:fa00:95:205:33c8:8e01:1161:6797]) by smtp.gmail.com with UTF8SMTPSA id m18sm5552391pff.88.2021.06.11.08.27.04 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 11 Jun 2021 08:27:11 -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, rodrigo.vivi@intel.com, thomas.hellstrom@linux.intel.com Subject: [PATCH v9 00/14] Restricted DMA Date: Fri, 11 Jun 2021 23:26:45 +0800 Message-Id: <20210611152659.2142983-1-tientzu@chromium.org> X-Mailer: git-send-email 2.32.0.272.g935e593368-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 v9: Address the comments in v7 to - set swiotlb active pool to dev->dma_io_tlb_mem - get rid of get_io_tlb_mem - dig out the device struct for is_swiotlb_active - move debugfs_create_dir out of swiotlb_create_debugfs - do set_memory_decrypted conditionally in swiotlb_init_io_tlb_mem - use IS_ENABLED in kernel/dma/direct.c - fix redefinition of 'of_dma_set_restricted_buffer' v8: - Fix reserved-memory.txt and add the reg property in example. - Fix sizeof for of_property_count_elems_of_size in drivers/of/address.c#of_dma_set_restricted_buffer. - Apply Will's suggestion to try the OF node having DMA configuration in drivers/of/address.c#of_dma_set_restricted_buffer. - Fix typo in the comment of drivers/of/address.c#of_dma_set_restricted_buffer. - Add error message for PageHighMem in kernel/dma/swiotlb.c#rmem_swiotlb_device_init and move it to rmem_swiotlb_setup. - Fix the message string in rmem_swiotlb_setup. https://lore.kernel.org/patchwork/cover/1437112/ v7: Fix debugfs, PageHighMem and comment style in rmem_swiotlb_device_init https://lore.kernel.org/patchwork/cover/1431031/ v6: Address the comments in v5 https://lore.kernel.org/patchwork/cover/1423201/ 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/ Claire Chang (14): swiotlb: Refactor swiotlb init functions swiotlb: Refactor swiotlb_create_debugfs swiotlb: Set dev->dma_io_tlb_mem to the swiotlb pool used swiotlb: Add restricted DMA pool initialization 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 | 36 ++- 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 | 33 +++ drivers/of/device.c | 6 + drivers/of/of_private.h | 6 + drivers/pci/xen-pcifront.c | 2 +- drivers/xen/swiotlb-xen.c | 2 +- include/linux/device.h | 4 + include/linux/swiotlb.h | 45 +++- kernel/dma/Kconfig | 14 + kernel/dma/direct.c | 62 +++-- kernel/dma/direct.h | 9 +- kernel/dma/swiotlb.c | 242 +++++++++++++----- 15 files changed, 376 insertions(+), 101 deletions(-)