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=-7.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,T_DKIMWL_WL_HIGH,URIBL_BLOCKED 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 6EB11C28CC5 for ; Sat, 8 Jun 2019 03:52:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 36F1A2146F for ; Sat, 8 Jun 2019 03:52:53 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="jSdD6RhF" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730471AbfFHDws (ORCPT ); Fri, 7 Jun 2019 23:52:48 -0400 Received: from mail-pf1-f194.google.com ([209.85.210.194]:38717 "EHLO mail-pf1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730445AbfFHDwr (ORCPT ); Fri, 7 Jun 2019 23:52:47 -0400 Received: by mail-pf1-f194.google.com with SMTP id a186so2231777pfa.5 for ; Fri, 07 Jun 2019 20:52:47 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=FvOvhN7lAMb05Jgucbn4i/kkfk6C+xm00bozwGUiDHE=; b=jSdD6RhFfZkeqgS8TcayMIER7Pkkx++KxJ0VlFLn9BvHk82PjgIJ2PrdItWwSzYW05 NLhWR71M5RDwErf/bBmmALg5hWrf7JykHz8MqC0HoRPvtnrf7wJZvYnVmInDaDa0hprb 7Wa5xVFo7VF+cw+RSx/ka7MEiF5SaHkm3s0FY= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=FvOvhN7lAMb05Jgucbn4i/kkfk6C+xm00bozwGUiDHE=; b=Mn7WGd3cJf2Qg5+wqfDjQm72Tt2YcHYUa0lMqYDW/1P6Id5CYXy3O+krvkmuEUdlGK aEtLp7d5K0vnGuhMXSNaKDprXqMc937sQKcCrih7V8iNK7c8K1YezDeQx6XFLBnKbGXm j95Dy5C7iZ0YURRrhaEsLFPkS92Z1fl3ZObQ3rH66DF3URtiIcEAo0rAdcbAPNTI3Qo+ naAgUFtzPM7oYs6GnPrTBwL5jBWSx2Aj4GO95kpTGDYIIkmDBzBrh9a5UZyYg9TJnflT cO+DLzzer3pvjvzVZFQ0BLM5DnAmmGYIOi7Hn2eKCs4u3BeqiIgqbUfgwrTPiyepcyuN dTCw== X-Gm-Message-State: APjAAAVTw7P/gQ4om5MI/NllYB2pBnEFFEouTfimgeT9/Pi/kgwGsibl EOYOG3nnzB0ZP8b5U8Ll8kf6UQ== X-Google-Smtp-Source: APXvYqwjIf2RUpKbV2HVLPuystSV0iOPs0w3Y10dXMrzubhjEtN6FPReOOA3bdEKg814UJFukvJHYg== X-Received: by 2002:a17:90a:37c8:: with SMTP id v66mr9429258pjb.33.1559965966947; Fri, 07 Jun 2019 20:52:46 -0700 (PDT) Received: from www.outflux.net (smtp.outflux.net. [198.145.64.163]) by smtp.gmail.com with ESMTPSA id l1sm3510268pgj.67.2019.06.07.20.52.45 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Fri, 07 Jun 2019 20:52:46 -0700 (PDT) Date: Fri, 7 Jun 2019 20:52:45 -0700 From: Kees Cook To: Andrey Konovalov Cc: 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, Catalin Marinas , Vincenzo Frascino , Will Deacon , Mark Rutland , Andrew Morton , Greg Kroah-Hartman , 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 , Mauro Carvalho Chehab Subject: Re: [PATCH v16 13/16] media/v4l2-core, arm64: untag user pointers in videobuf_dma_contig_user_get Message-ID: <201906072052.077135B@keescook> References: <31821f3538ddacb7e57e0248e86a3d28f9789d2f.1559580831.git.andreyknvl@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <31821f3538ddacb7e57e0248e86a3d28f9789d2f.1559580831.git.andreyknvl@google.com> Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Mon, Jun 03, 2019 at 06:55:15PM +0200, 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. > > videobuf_dma_contig_user_get() uses provided user pointers for vma > lookups, which can only by done with untagged pointers. > > Untag the pointers in this function. > > Acked-by: Mauro Carvalho Chehab > Signed-off-by: Andrey Konovalov Reviewed-by: Kees Cook -Kees > --- > drivers/media/v4l2-core/videobuf-dma-contig.c | 9 +++++---- > 1 file changed, 5 insertions(+), 4 deletions(-) > > diff --git a/drivers/media/v4l2-core/videobuf-dma-contig.c b/drivers/media/v4l2-core/videobuf-dma-contig.c > index e1bf50df4c70..8a1ddd146b17 100644 > --- a/drivers/media/v4l2-core/videobuf-dma-contig.c > +++ b/drivers/media/v4l2-core/videobuf-dma-contig.c > @@ -160,6 +160,7 @@ static void videobuf_dma_contig_user_put(struct videobuf_dma_contig_memory *mem) > static int videobuf_dma_contig_user_get(struct videobuf_dma_contig_memory *mem, > struct videobuf_buffer *vb) > { > + unsigned long untagged_baddr = untagged_addr(vb->baddr); > struct mm_struct *mm = current->mm; > struct vm_area_struct *vma; > unsigned long prev_pfn, this_pfn; > @@ -167,22 +168,22 @@ static int videobuf_dma_contig_user_get(struct videobuf_dma_contig_memory *mem, > unsigned int offset; > int ret; > > - offset = vb->baddr & ~PAGE_MASK; > + offset = untagged_baddr & ~PAGE_MASK; > mem->size = PAGE_ALIGN(vb->size + offset); > ret = -EINVAL; > > down_read(&mm->mmap_sem); > > - vma = find_vma(mm, vb->baddr); > + vma = find_vma(mm, untagged_baddr); > if (!vma) > goto out_up; > > - if ((vb->baddr + mem->size) > vma->vm_end) > + if ((untagged_baddr + mem->size) > vma->vm_end) > goto out_up; > > pages_done = 0; > prev_pfn = 0; /* kill warning */ > - user_address = vb->baddr; > + user_address = untagged_baddr; > > while (pages_done < (mem->size >> PAGE_SHIFT)) { > ret = follow_pfn(vma, user_address, &this_pfn); > -- > 2.22.0.rc1.311.g5d7573a151-goog > -- Kees Cook