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=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 531D0C282DD for ; Thu, 9 Jan 2020 13:23:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 25D41206ED for ; Thu, 9 Jan 2020 13:23:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731045AbgAINXR (ORCPT ); Thu, 9 Jan 2020 08:23:17 -0500 Received: from foss.arm.com ([217.140.110.172]:58962 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727861AbgAINXR (ORCPT ); Thu, 9 Jan 2020 08:23:17 -0500 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 C00EE31B; Thu, 9 Jan 2020 05:23:16 -0800 (PST) Received: from [10.1.196.37] (e121345-lin.cambridge.arm.com [10.1.196.37]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id DAA833F534; Thu, 9 Jan 2020 05:23:15 -0800 (PST) Subject: Re: [PATCH] iommu/arm-smmu-v3: fix resource_size check To: Masahiro Yamada , Will Deacon , linux-arm-kernel@lists.infradead.org, Joerg Roedel , iommu@lists.linux-foundation.org Cc: linux-kernel@vger.kernel.org References: <20191226095056.30256-1-yamada.masahiro@socionext.com> From: Robin Murphy Message-ID: <2cd8ed11-56df-b46b-aa21-5ecc0e2e3082@arm.com> Date: Thu, 9 Jan 2020 13:23:14 +0000 User-Agent: Mozilla/5.0 (X11; Linux aarch64; rv:60.0) Gecko/20100101 Thunderbird/60.9.0 MIME-Version: 1.0 In-Reply-To: <20191226095056.30256-1-yamada.masahiro@socionext.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-GB Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 26/12/2019 9:50 am, Masahiro Yamada wrote: > This is an off-by-one mistake. > > resource_size() returns res->end - res->start + 1. Heh, despite the optimism of "Avoid one-off errors by introducing a resource_size() function", life finds a way... Reviewed-by: Robin Murphy > Signed-off-by: Masahiro Yamada > --- > > drivers/iommu/arm-smmu-v3.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c > index d9e0d9c19b4f..b463599559d2 100644 > --- a/drivers/iommu/arm-smmu-v3.c > +++ b/drivers/iommu/arm-smmu-v3.c > @@ -3599,7 +3599,7 @@ static int arm_smmu_device_probe(struct platform_device *pdev) > > /* Base address */ > res = platform_get_resource(pdev, IORESOURCE_MEM, 0); > - if (resource_size(res) + 1 < arm_smmu_resource_size(smmu)) { > + if (resource_size(res) < arm_smmu_resource_size(smmu)) { > dev_err(dev, "MMIO region too small (%pr)\n", res); > return -EINVAL; > } >