From patchwork Fri Nov 27 16:41:22 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Daniel Vetter X-Patchwork-Id: 1407327 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=linux-pci-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=ffwll.ch Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; secure) header.d=ffwll.ch header.i=@ffwll.ch header.a=rsa-sha256 header.s=google header.b=KobUOV0h; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 4CjL5z2zkrz9sVJ for ; Sat, 28 Nov 2020 03:43:03 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731772AbgK0QmL (ORCPT ); Fri, 27 Nov 2020 11:42:11 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54030 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731716AbgK0QmK (ORCPT ); Fri, 27 Nov 2020 11:42:10 -0500 Received: from mail-wm1-x341.google.com (mail-wm1-x341.google.com [IPv6:2a00:1450:4864:20::341]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 89CFEC061A47 for ; Fri, 27 Nov 2020 08:42:09 -0800 (PST) Received: by mail-wm1-x341.google.com with SMTP id d3so2540862wmb.4 for ; Fri, 27 Nov 2020 08:42:09 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ffwll.ch; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=rOg+qp39SVj5WC86VkdFnTzL9jP06PEcpQhmqKQ3t14=; b=KobUOV0hD77WVAdN6sE1FCbuddcx+Y7JofzkUlxRd9nWy9jlHdO1T8SsUttmc9LdEH 18FkNkVd0nL6VbYr5rOcMNJq8lcpuHF9LitOz/7CtQcZOgTCuvVk9HlpE337IvJ3CeQo TbfkBVcsC/WpwsEsC3qnjZtZkVocnIVEGrM9Q= 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:in-reply-to :references:mime-version:content-transfer-encoding; bh=rOg+qp39SVj5WC86VkdFnTzL9jP06PEcpQhmqKQ3t14=; b=RzMCPneYyGBWkhFF5k0U+XOujMElcODC+spdfrAVjKKnrU2dK4y7kQZpBfdfkuOH6W 3rxWOSmd/yJbQDe5NfXrJhsusfD8HTS1wKLQAztxGwylaV7d7YHiqM9qev3QwVZELmM+ sLQvUoZ1W4a9fyKESuZSBqwYYz3zmq9xPCxzCadlVPt3JvMuR/HK7H904vJK5ZIzwThM 9g+9M3P59yNrt5evCPa0ADAAv2zbOFuCqFo5826TEfHDp9pHSQFuMTrPryZfXY+RKbGq iSG6Ae9AHL5y6ZK4zT0ds8olK6pmd+tiO7q7nDsTwudG9HjVTNsIPwdxddfyUNvmv6mC mbhw== X-Gm-Message-State: AOAM530eFsb2+7WVhXctYGd8H5zPaezHpi/zf94l/oofmgBNUYqRjk1R vmoDwQlSMBEMPOvO6tBNLuwULQ== X-Google-Smtp-Source: ABdhPJzZvF4udC7vFRIpQiicdsquYnu262AHQt4sYjvK76p1I545qbyBbBNxGngNqssLcpNV9573Nw== X-Received: by 2002:a1c:4944:: with SMTP id w65mr10125938wma.50.1606495328317; Fri, 27 Nov 2020 08:42:08 -0800 (PST) Received: from phenom.ffwll.local ([2a02:168:57f4:0:efd0:b9e5:5ae6:c2fa]) by smtp.gmail.com with ESMTPSA id q12sm14859078wrx.86.2020.11.27.08.42.07 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 27 Nov 2020 08:42:07 -0800 (PST) From: Daniel Vetter To: DRI Development , LKML Cc: kvm@vger.kernel.org, linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, linux-samsung-soc@vger.kernel.org, linux-media@vger.kernel.org, Daniel Vetter , Bjorn Helgaas , Daniel Vetter , Jason Gunthorpe , Kees Cook , Dan Williams , Andrew Morton , John Hubbard , =?utf-8?b?SsOpcsO0bWUgR2xpc3Nl?= , Jan Kara , linux-pci@vger.kernel.org Subject: [PATCH v7 08/17] PCI: Obey iomem restrictions for procfs mmap Date: Fri, 27 Nov 2020 17:41:22 +0100 Message-Id: <20201127164131.2244124-9-daniel.vetter@ffwll.ch> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201127164131.2244124-1-daniel.vetter@ffwll.ch> References: <20201127164131.2244124-1-daniel.vetter@ffwll.ch> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org There's three ways to access PCI BARs from userspace: /dev/mem, sysfs files, and the old proc interface. Two check against iomem_is_exclusive, proc never did. And with CONFIG_IO_STRICT_DEVMEM, this starts to matter, since we don't want random userspace having access to PCI BARs while a driver is loaded and using it. Fix this by adding the same iomem_is_exclusive() check we already have on the sysfs side in pci_mmap_resource(). Acked-by: Bjorn Helgaas References: 90a545e98126 ("restrict /dev/mem to idle io memory ranges") Signed-off-by: Daniel Vetter Cc: Jason Gunthorpe Cc: Kees Cook Cc: Dan Williams Cc: Andrew Morton Cc: John Hubbard Cc: Jérôme Glisse Cc: Jan Kara Cc: Dan Williams Cc: linux-mm@kvack.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-samsung-soc@vger.kernel.org Cc: linux-media@vger.kernel.org Cc: Bjorn Helgaas Cc: linux-pci@vger.kernel.org Signed-off-by: Daniel Vetter --- v2: Improve commit message (Bjorn) --- drivers/pci/proc.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/pci/proc.c b/drivers/pci/proc.c index d35186b01d98..3a2f90beb4cb 100644 --- a/drivers/pci/proc.c +++ b/drivers/pci/proc.c @@ -274,6 +274,11 @@ static int proc_bus_pci_mmap(struct file *file, struct vm_area_struct *vma) else return -EINVAL; } + + if (dev->resource[i].flags & IORESOURCE_MEM && + iomem_is_exclusive(dev->resource[i].start)) + return -EINVAL; + ret = pci_mmap_page_range(dev, i, vma, fpriv->mmap_state, write_combine); if (ret < 0) From patchwork Fri Nov 27 16:41:25 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Daniel Vetter X-Patchwork-Id: 1407329 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=linux-pci-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=ffwll.ch Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; secure) header.d=ffwll.ch header.i=@ffwll.ch header.a=rsa-sha256 header.s=google header.b=PQkuXj5f; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 4CjL6118K0z9sVN for ; Sat, 28 Nov 2020 03:43:05 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731852AbgK0QmQ (ORCPT ); Fri, 27 Nov 2020 11:42:16 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54064 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731856AbgK0QmP (ORCPT ); Fri, 27 Nov 2020 11:42:15 -0500 Received: from mail-wr1-x444.google.com (mail-wr1-x444.google.com [IPv6:2a00:1450:4864:20::444]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B7CBEC061A04 for ; Fri, 27 Nov 2020 08:42:13 -0800 (PST) Received: by mail-wr1-x444.google.com with SMTP id l1so6193567wrb.9 for ; Fri, 27 Nov 2020 08:42:13 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ffwll.ch; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=rW60Jo5EYOrfW48enxn4HuDZHwz18Yu4cEXjV+kmxhI=; b=PQkuXj5frTE5y11eiKAgq79LrIZ8tE/zx4eh3eEZQp6giLCWCHkekWBtjZn+b6apiX OettDGs7KeV6c1u5GVEgBTyePxi+k0YgxvAkEqvC0lu/PHO5FoD5SaGsKYrsR8iraWxV gzEOq3melTr0FDtkd450cWQdzdipC9arwKkow= 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:in-reply-to :references:mime-version:content-transfer-encoding; bh=rW60Jo5EYOrfW48enxn4HuDZHwz18Yu4cEXjV+kmxhI=; b=pBvJGCNdrz4trOXj4FHzSXJWtDaF9JeTzjQkz3IYceH/4yzGEOEN+8QdY8cHeVA9l3 eTnGnHZQhtacqdvwb9DOKcqdwXLGSqyzjlI6RklgoR0eLbCwjj8n9ogHvG57Pz6bhnnK uBcFSiCOXncHR3ssrWPtkB/zdJLsKAwqa/ECjver+zPf22T9IXjgyFpRpeLkb800zMIa NLx04Vz70B/9PAjBspck/9+bmNY/onv33gfVcHw3njCatF/B5AJxvSJfU8WzeFSdDIDC p9CCn9XUNQU+qv9ZTVkn9wMYZSThGUDmwX+I5j1XjA8nv1+xSZAcdO46G2Et90xHtydE XsSQ== X-Gm-Message-State: AOAM532pXcV1yPKUA21EjLQOy7xkRsRV1HUVvRC3mb2LYFMCT9B6aP3G cx6qD3WI3fWzrjgTNGi+I/jWcA== X-Google-Smtp-Source: ABdhPJy7N8sWlvrZkrO6DwKDVYKhPGfBm7BDjLJVeT6c/8cd28+5xGF25PU+qwVqK2WiY3xNRptmuw== X-Received: by 2002:adf:f3d1:: with SMTP id g17mr11762819wrp.201.1606495332522; Fri, 27 Nov 2020 08:42:12 -0800 (PST) Received: from phenom.ffwll.local ([2a02:168:57f4:0:efd0:b9e5:5ae6:c2fa]) by smtp.gmail.com with ESMTPSA id q12sm14859078wrx.86.2020.11.27.08.42.11 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 27 Nov 2020 08:42:11 -0800 (PST) From: Daniel Vetter To: DRI Development , LKML Cc: kvm@vger.kernel.org, linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, linux-samsung-soc@vger.kernel.org, linux-media@vger.kernel.org, Daniel Vetter , Greg Kroah-Hartman , Daniel Vetter , Jason Gunthorpe , Kees Cook , Dan Williams , Andrew Morton , John Hubbard , =?utf-8?b?SsOpcsO0bWUgR2xpc3Nl?= , Jan Kara , Bjorn Helgaas , linux-pci@vger.kernel.org, "Rafael J. Wysocki" , Christian Brauner , "David S. Miller" , Michael Ellerman , Sourabh Jain , Mauro Carvalho Chehab , Nayna Jain Subject: [PATCH v7 11/17] sysfs: Support zapping of binary attr mmaps Date: Fri, 27 Nov 2020 17:41:25 +0100 Message-Id: <20201127164131.2244124-12-daniel.vetter@ffwll.ch> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201127164131.2244124-1-daniel.vetter@ffwll.ch> References: <20201127164131.2244124-1-daniel.vetter@ffwll.ch> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org We want to be able to revoke pci mmaps so that the same access rules applies as for /dev/kmem. Revoke support for devmem was added in 3234ac664a87 ("/dev/mem: Revoke mappings when a driver claims the region"). The simplest way to achieve this is by having the same filp->f_mapping for all mappings, so that unmap_mapping_range can find them all, no matter through which file they've been created. Since this must be set at open time we need sysfs support for this. Add an optional mapping parameter bin_attr, which is only consulted when there's also an mmap callback, since without mmap support allowing to adjust the ->f_mapping makes no sense. Reviewed-by: Greg Kroah-Hartman Signed-off-by: Daniel Vetter Cc: Jason Gunthorpe Cc: Kees Cook Cc: Dan Williams Cc: Andrew Morton Cc: John Hubbard Cc: Jérôme Glisse Cc: Jan Kara Cc: Dan Williams Cc: linux-mm@kvack.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-samsung-soc@vger.kernel.org Cc: linux-media@vger.kernel.org Cc: Bjorn Helgaas Cc: linux-pci@vger.kernel.org Cc: Greg Kroah-Hartman Cc: "Rafael J. Wysocki" Cc: Christian Brauner Cc: "David S. Miller" Cc: Michael Ellerman Cc: Sourabh Jain Cc: Daniel Vetter Cc: Mauro Carvalho Chehab Cc: Nayna Jain Signed-off-by: Daniel Vetter --- fs/sysfs/file.c | 11 +++++++++++ include/linux/sysfs.h | 2 ++ 2 files changed, 13 insertions(+) diff --git a/fs/sysfs/file.c b/fs/sysfs/file.c index 96d0da65e088..9aefa7779b29 100644 --- a/fs/sysfs/file.c +++ b/fs/sysfs/file.c @@ -170,6 +170,16 @@ static int sysfs_kf_bin_mmap(struct kernfs_open_file *of, return battr->mmap(of->file, kobj, battr, vma); } +static int sysfs_kf_bin_open(struct kernfs_open_file *of) +{ + struct bin_attribute *battr = of->kn->priv; + + if (battr->mapping) + of->file->f_mapping = battr->mapping; + + return 0; +} + void sysfs_notify(struct kobject *kobj, const char *dir, const char *attr) { struct kernfs_node *kn = kobj->sd, *tmp; @@ -241,6 +251,7 @@ static const struct kernfs_ops sysfs_bin_kfops_mmap = { .read = sysfs_kf_bin_read, .write = sysfs_kf_bin_write, .mmap = sysfs_kf_bin_mmap, + .open = sysfs_kf_bin_open, }; int sysfs_add_file_mode_ns(struct kernfs_node *parent, diff --git a/include/linux/sysfs.h b/include/linux/sysfs.h index 2caa34c1ca1a..d76a1ddf83a3 100644 --- a/include/linux/sysfs.h +++ b/include/linux/sysfs.h @@ -164,11 +164,13 @@ __ATTRIBUTE_GROUPS(_name) struct file; struct vm_area_struct; +struct address_space; struct bin_attribute { struct attribute attr; size_t size; void *private; + struct address_space *mapping; ssize_t (*read)(struct file *, struct kobject *, struct bin_attribute *, char *, loff_t, size_t); ssize_t (*write)(struct file *, struct kobject *, struct bin_attribute *, From patchwork Fri Nov 27 16:41:26 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Daniel Vetter X-Patchwork-Id: 1407328 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=linux-pci-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=ffwll.ch Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; secure) header.d=ffwll.ch header.i=@ffwll.ch header.a=rsa-sha256 header.s=google header.b=bfdMAxwy; 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Fri, 27 Nov 2020 08:42:13 -0800 (PST) Received: from phenom.ffwll.local ([2a02:168:57f4:0:efd0:b9e5:5ae6:c2fa]) by smtp.gmail.com with ESMTPSA id q12sm14859078wrx.86.2020.11.27.08.42.12 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 27 Nov 2020 08:42:13 -0800 (PST) From: Daniel Vetter To: DRI Development , LKML Cc: kvm@vger.kernel.org, linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, linux-samsung-soc@vger.kernel.org, linux-media@vger.kernel.org, Daniel Vetter , Bjorn Helgaas , Dan Williams , Daniel Vetter , Jason Gunthorpe , Kees Cook , Andrew Morton , John Hubbard , =?utf-8?b?SsOpcsO0bWUgR2xpc3Nl?= , Jan Kara , Greg Kroah-Hartman , linux-pci@vger.kernel.org Subject: [PATCH v7 12/17] PCI: Revoke mappings like devmem Date: Fri, 27 Nov 2020 17:41:26 +0100 Message-Id: <20201127164131.2244124-13-daniel.vetter@ffwll.ch> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201127164131.2244124-1-daniel.vetter@ffwll.ch> References: <20201127164131.2244124-1-daniel.vetter@ffwll.ch> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Since 3234ac664a87 ("/dev/mem: Revoke mappings when a driver claims the region") /dev/kmem zaps ptes when the kernel requests exclusive acccess to an iomem region. And with CONFIG_IO_STRICT_DEVMEM, this is the default for all driver uses. Except there's two more ways to access PCI BARs: sysfs and proc mmap support. Let's plug that hole. For revoke_devmem() to work we need to link our vma into the same address_space, with consistent vma->vm_pgoff. ->pgoff is already adjusted, because that's how (io_)remap_pfn_range works, but for the mapping we need to adjust vma->vm_file->f_mapping. The cleanest way is to adjust this at at ->open time: - for sysfs this is easy, now that binary attributes support this. We just set bin_attr->mapping when mmap is supported - for procfs it's a bit more tricky, since procfs pci access has only one file per device, and access to a specific resources first needs to be set up with some ioctl calls. But mmap is only supported for the same resources as sysfs exposes with mmap support, and otherwise rejected, so we can set the mapping unconditionally at open time without harm. A special consideration is for arch_can_pci_mmap_io() - we need to make sure that the ->f_mapping doesn't alias between ioport and iomem space. There's only 2 ways in-tree to support mmap of ioports: generic pci mmap (ARCH_GENERIC_PCI_MMAP_RESOURCE), and sparc as the single architecture hand-rolling. Both approach support ioport mmap through a special pfn range and not through magic pte attributes. Aliasing is therefore not a problem. The only difference in access checks left is that sysfs PCI mmap does not check for CAP_RAWIO. I'm not really sure whether that should be added or not. Acked-by: Bjorn Helgaas Reviewed-by: Dan Williams Signed-off-by: Daniel Vetter Cc: Jason Gunthorpe Cc: Kees Cook Cc: Dan Williams Cc: Andrew Morton Cc: John Hubbard Cc: Jérôme Glisse Cc: Jan Kara Cc: Dan Williams Cc: Greg Kroah-Hartman Cc: linux-mm@kvack.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-samsung-soc@vger.kernel.org Cc: linux-media@vger.kernel.org Cc: Bjorn Helgaas Cc: linux-pci@vger.kernel.org Signed-off-by: Daniel Vetter --- v2: - Totally new approach: Adjust filp->f_mapping at open time. Note that this now works on all architectures, not just those support ARCH_GENERIC_PCI_MMAP_RESOURCE --- drivers/pci/pci-sysfs.c | 4 ++++ drivers/pci/proc.c | 1 + 2 files changed, 5 insertions(+) diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c index d15c881e2e7e..3f1c31bc0b7c 100644 --- a/drivers/pci/pci-sysfs.c +++ b/drivers/pci/pci-sysfs.c @@ -929,6 +929,7 @@ void pci_create_legacy_files(struct pci_bus *b) b->legacy_io->read = pci_read_legacy_io; b->legacy_io->write = pci_write_legacy_io; b->legacy_io->mmap = pci_mmap_legacy_io; + b->legacy_io->mapping = iomem_get_mapping(); pci_adjust_legacy_attr(b, pci_mmap_io); error = device_create_bin_file(&b->dev, b->legacy_io); if (error) @@ -941,6 +942,7 @@ void pci_create_legacy_files(struct pci_bus *b) b->legacy_mem->size = 1024*1024; b->legacy_mem->attr.mode = 0600; b->legacy_mem->mmap = pci_mmap_legacy_mem; + b->legacy_io->mapping = iomem_get_mapping(); pci_adjust_legacy_attr(b, pci_mmap_mem); error = device_create_bin_file(&b->dev, b->legacy_mem); if (error) @@ -1156,6 +1158,8 @@ static int pci_create_attr(struct pci_dev *pdev, int num, int write_combine) res_attr->mmap = pci_mmap_resource_uc; } } + if (res_attr->mmap) + res_attr->mapping = iomem_get_mapping(); res_attr->attr.name = res_attr_name; res_attr->attr.mode = 0600; res_attr->size = pci_resource_len(pdev, num); diff --git a/drivers/pci/proc.c b/drivers/pci/proc.c index 3a2f90beb4cb..9bab07302bbf 100644 --- a/drivers/pci/proc.c +++ b/drivers/pci/proc.c @@ -298,6 +298,7 @@ static int proc_bus_pci_open(struct inode *inode, struct file *file) fpriv->write_combine = 0; file->private_data = fpriv; + file->f_mapping = iomem_get_mapping(); return 0; }