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=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS 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 2AD59C31E46 for ; Wed, 12 Jun 2019 14:42:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0C76A208CA for ; Wed, 12 Jun 2019 14:42:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2437957AbfFLOmF (ORCPT ); Wed, 12 Jun 2019 10:42:05 -0400 Received: from foss.arm.com ([217.140.110.172]:54838 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731969AbfFLOmF (ORCPT ); Wed, 12 Jun 2019 10:42:05 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 6763C2B; Wed, 12 Jun 2019 07:42:04 -0700 (PDT) Received: from [10.1.196.72] (e119884-lin.cambridge.arm.com [10.1.196.72]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id EF8A33F557; Wed, 12 Jun 2019 07:41:58 -0700 (PDT) Subject: Re: [PATCH v17 14/15] vfio/type1, arm64: untag user pointers in vaddr_get_pfn To: Andrey Konovalov , linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, amd-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-rdma@vger.kernel.org, linux-media@vger.kernel.org, kvm@vger.kernel.org, linux-kselftest@vger.kernel.org Cc: Catalin Marinas , Will Deacon , Mark Rutland , Andrew Morton , Greg Kroah-Hartman , Kees Cook , Yishai Hadas , Felix Kuehling , Alexander Deucher , Christian Koenig , Mauro Carvalho Chehab , Jens Wiklander , Alex Williamson , Leon Romanovsky , Luc Van Oostenryck , Dave Martin , Khalid Aziz , enh , Jason Gunthorpe , Christoph Hellwig , Dmitry Vyukov , Kostya Serebryany , Evgeniy Stepanov , Lee Smith , Ramana Radhakrishnan , Jacob Bramley , Ruben Ayrapetyan , Robin Murphy , Kevin Brodsky , Szabolcs Nagy References: From: Vincenzo Frascino Message-ID: Date: Wed, 12 Jun 2019 15:41:57 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On 12/06/2019 12:43, Andrey Konovalov wrote: > This patch is a part of a series that extends arm64 kernel ABI to allow to > pass tagged user pointers (with the top byte set to something else other > than 0x00) as syscall arguments. > > vaddr_get_pfn() uses provided user pointers for vma lookups, which can > only by done with untagged pointers. > > Untag user pointers in this function. > > Reviewed-by: Catalin Marinas > Reviewed-by: Kees Cook > Signed-off-by: Andrey Konovalov Reviewed-by: Vincenzo Frascino > --- > drivers/vfio/vfio_iommu_type1.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c > index 3ddc375e7063..528e39a1c2dd 100644 > --- a/drivers/vfio/vfio_iommu_type1.c > +++ b/drivers/vfio/vfio_iommu_type1.c > @@ -384,6 +384,8 @@ static int vaddr_get_pfn(struct mm_struct *mm, unsigned long vaddr, > > down_read(&mm->mmap_sem); > > + vaddr = untagged_addr(vaddr); > + > vma = find_vma_intersection(mm, vaddr, vaddr + 1); > > if (vma && vma->vm_flags & VM_PFNMAP) { > -- Regards, Vincenzo