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=-13.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, 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 194D7C433ED for ; Tue, 14 Jul 2020 19:04:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E9A062240B for ; Tue, 14 Jul 2020 19:04:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1594753492; bh=/63arVv2yF+aZ8Pzf5dquTJuilNwkjyY26Szdcnco3I=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=l8aElRXSbYYSmjAxfeL15RrJXnjSsgaMWfVXMax04rMf04nx9zRIA9ea49esjQxbQ FbUuWcZTlGaGTc4n2y/vlyrj51tmnAdoqb9V5w+MIu7Awo0IJPiyv1WXONwH/Tb4HO BCJRTJ2O1N/RhqGQOOAYN4dPoRRu8GqB1Y5XObcs= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729893AbgGNTEt (ORCPT ); Tue, 14 Jul 2020 15:04:49 -0400 Received: from mail.kernel.org ([198.145.29.99]:53438 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729718AbgGNSzl (ORCPT ); Tue, 14 Jul 2020 14:55:41 -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 45A5B22282; Tue, 14 Jul 2020 18:55:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1594752940; bh=/63arVv2yF+aZ8Pzf5dquTJuilNwkjyY26Szdcnco3I=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=NjN+rqZNn1AG3hf1g8nE5GGEhJHvU/z8Scmdz1xfcDG/ZIRzDqRcM4cvPscceS88K SrkZy8PYPeimR5H5U2UgduOJ3vO3LhO9IuiwVMnL34XqtiA8HWm+dLJ4BIB0MhYT6A ko4TtK4UqBdhFl5Yn5H/TSPPnmnP9HHhEOChD0Sk= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Rajat Jain , Ashok Raj , Mika Westerberg , Lu Baolu , Joerg Roedel , Sasha Levin Subject: [PATCH 5.7 028/166] iommu/vt-d: Dont apply gfx quirks to untrusted devices Date: Tue, 14 Jul 2020 20:43:13 +0200 Message-Id: <20200714184117.232454967@linuxfoundation.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714184115.844176932@linuxfoundation.org> References: <20200714184115.844176932@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Rajat Jain [ Upstream commit 67e8a5b18d41af9298db5c17193f671f235cce01 ] Currently, an external malicious PCI device can masquerade the VID:PID of faulty gfx devices, and thus apply iommu quirks to effectively disable the IOMMU restrictions for itself. Thus we need to ensure that the device we are applying quirks to, is indeed an internal trusted device. Signed-off-by: Rajat Jain Reviewed-by: Ashok Raj Reviewed-by: Mika Westerberg Acked-by: Lu Baolu Link: https://lore.kernel.org/r/20200622231345.29722-4-baolu.lu@linux.intel.com Signed-off-by: Joerg Roedel Signed-off-by: Sasha Levin --- drivers/iommu/intel-iommu.c | 37 +++++++++++++++++++++++++++++++++++++ 1 file changed, 37 insertions(+) diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c index 34b2ed91cf4d9..2acf2842c3bd2 100644 --- a/drivers/iommu/intel-iommu.c +++ b/drivers/iommu/intel-iommu.c @@ -6206,6 +6206,23 @@ intel_iommu_domain_set_attr(struct iommu_domain *domain, return ret; } +/* + * Check that the device does not live on an external facing PCI port that is + * marked as untrusted. Such devices should not be able to apply quirks and + * thus not be able to bypass the IOMMU restrictions. + */ +static bool risky_device(struct pci_dev *pdev) +{ + if (pdev->untrusted) { + pci_info(pdev, + "Skipping IOMMU quirk for dev [%04X:%04X] on untrusted PCI link\n", + pdev->vendor, pdev->device); + pci_info(pdev, "Please check with your BIOS/Platform vendor about this\n"); + return true; + } + return false; +} + const struct iommu_ops intel_iommu_ops = { .capable = intel_iommu_capable, .domain_alloc = intel_iommu_domain_alloc, @@ -6235,6 +6252,9 @@ const struct iommu_ops intel_iommu_ops = { static void quirk_iommu_igfx(struct pci_dev *dev) { + if (risky_device(dev)) + return; + pci_info(dev, "Disabling IOMMU for graphics on this chipset\n"); dmar_map_gfx = 0; } @@ -6276,6 +6296,9 @@ DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x163D, quirk_iommu_igfx); static void quirk_iommu_rwbf(struct pci_dev *dev) { + if (risky_device(dev)) + return; + /* * Mobile 4 Series Chipset neglects to set RWBF capability, * but needs it. Same seems to hold for the desktop versions. @@ -6306,6 +6329,9 @@ static void quirk_calpella_no_shadow_gtt(struct pci_dev *dev) { unsigned short ggc; + if (risky_device(dev)) + return; + if (pci_read_config_word(dev, GGC, &ggc)) return; @@ -6339,6 +6365,12 @@ static void __init check_tylersburg_isoch(void) pdev = pci_get_device(PCI_VENDOR_ID_INTEL, 0x3a3e, NULL); if (!pdev) return; + + if (risky_device(pdev)) { + pci_dev_put(pdev); + return; + } + pci_dev_put(pdev); /* System Management Registers. Might be hidden, in which case @@ -6348,6 +6380,11 @@ static void __init check_tylersburg_isoch(void) if (!pdev) return; + if (risky_device(pdev)) { + pci_dev_put(pdev); + return; + } + if (pci_read_config_dword(pdev, 0x188, &vtisochctrl)) { pci_dev_put(pdev); return; -- 2.25.1