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=-6.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=ham 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 96AD6C2D0F4 for ; Wed, 8 Apr 2020 16:59:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6898D2072F for ; Wed, 8 Apr 2020 16:59:49 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="GShUeMzL" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730477AbgDHQ7s (ORCPT ); Wed, 8 Apr 2020 12:59:48 -0400 Received: from mail-pg1-f195.google.com ([209.85.215.195]:40819 "EHLO mail-pg1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729453AbgDHQ7s (ORCPT ); Wed, 8 Apr 2020 12:59:48 -0400 Received: by mail-pg1-f195.google.com with SMTP id c5so3581358pgi.7 for ; Wed, 08 Apr 2020 09:59:47 -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=iazuwtOmYpAvBrdVj8TEytSBmpAo+XIqBVbhsQf9qWM=; b=GShUeMzLckvv1Tmg/eAf8t2/jmGL2cG48LI9uDJAFRP21EjcCDQiSiVBJ+ufSQw2X+ zL3weCklxHnyTNA/snfQcDCUMSk26gYSWAy6MWK2OB5pnBbGPUaXkSO8yZD5WO11PdF2 7SNL4pPJ+c1FzVG0s72ZaI3wsEdVbtmkhh8eQ= 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=iazuwtOmYpAvBrdVj8TEytSBmpAo+XIqBVbhsQf9qWM=; b=QmvlugzoZTygcnQQLti+DcCftVtIYR06jBfNBzsVOOVuar7URvrJoUs1p7Bd7j7EPv otZfa82fQvGuWrA+2CkVMSIzzP9pMlzUV0WWs+D8Hh7EpiUyk3OZypZrhYGkFJThHmtb tWLdRsejnWzGpyb/iJccPIos6Q/ocdWkHVbRNnSTd56+ToUlrrkX3epzr59X3x8IJm2W T5yC6I/bPW3VpXKZamfxAehzZNEZ4h92THlyXVUMjEHIZ1X+Uzso5m9NuIXcQ0pfP2sk uUDO4wkb2IRp8Ba5J+zGRmv55vHGoOxqiudp+lzYByGQgrlGKX7zw98zMZwVzt7Bp4BL wAXg== X-Gm-Message-State: AGi0PuZPjNN0vUncoVLDOIR3nh7ejJp6yFX077UJmmjACxm2rADWtw0P z6VXDCqxynWVM0CSiPY2ms7zPg== X-Google-Smtp-Source: APiQypLbXC98cOz1Gk+AUmoZ9LfVbVf3dMcxa3rqqbc4bIsPb4a7998lvJd5neuYRjqaKOSq7JvUbQ== X-Received: by 2002:a63:f658:: with SMTP id u24mr836796pgj.357.1586365186839; Wed, 08 Apr 2020 09:59:46 -0700 (PDT) Received: from www.outflux.net (smtp.outflux.net. [198.145.64.163]) by smtp.gmail.com with ESMTPSA id h34sm60200pjb.47.2020.04.08.09.59.45 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 08 Apr 2020 09:59:45 -0700 (PDT) Date: Wed, 8 Apr 2020 09:59:44 -0700 From: Kees Cook To: Yan Zhao Cc: alex.williamson@redhat.com, cohuck@redhat.com, kvm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] vfio: checking of validity of user vaddr in vfio_dma_rw Message-ID: <202004080959.8C71F8DF7@keescook> References: <20200408071121.25645-1-yan.y.zhao@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200408071121.25645-1-yan.y.zhao@intel.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Apr 08, 2020 at 03:11:21AM -0400, Yan Zhao wrote: > instead of calling __copy_to/from_user(), use copy_to_from_user() to > ensure vaddr range is a valid user address range before accessing them. > > Cc: Kees Cook > > Fixes: 8d46c0cca5f4 ("vfio: introduce vfio_dma_rw to read/write a range of IOVAs") > Signed-off-by: Yan Zhao Thanks! Reported-by: Kees Cook Reviewed-by: Kees Cook -Kees > --- > drivers/vfio/vfio_iommu_type1.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c > index 3aefcc8e2933..fbc58284b333 100644 > --- a/drivers/vfio/vfio_iommu_type1.c > +++ b/drivers/vfio/vfio_iommu_type1.c > @@ -2345,10 +2345,10 @@ static int vfio_iommu_type1_dma_rw_chunk(struct vfio_iommu *iommu, > vaddr = dma->vaddr + offset; > > if (write) > - *copied = __copy_to_user((void __user *)vaddr, data, > + *copied = copy_to_user((void __user *)vaddr, data, > count) ? 0 : count; > else > - *copied = __copy_from_user(data, (void __user *)vaddr, > + *copied = copy_from_user(data, (void __user *)vaddr, > count) ? 0 : count; > if (kthread) > unuse_mm(mm); > -- > 2.17.1 > -- Kees Cook