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=-8.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS, URIBL_BLOCKED,USER_AGENT_MUTT 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 3AC38C43387 for ; Fri, 21 Dec 2018 01:21:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 05C8F21903 for ; Fri, 21 Dec 2018 01:21:22 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="Ctoge73q" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388087AbeLUBVU (ORCPT ); Thu, 20 Dec 2018 20:21:20 -0500 Received: from mail-pg1-f193.google.com ([209.85.215.193]:38775 "EHLO mail-pg1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730371AbeLUBVU (ORCPT ); Thu, 20 Dec 2018 20:21:20 -0500 Received: by mail-pg1-f193.google.com with SMTP id g189so1700240pgc.5 for ; Thu, 20 Dec 2018 17:21:19 -0800 (PST) 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:user-agent; bh=zgoeSxe5mtUlsZsWEbnATz+W4ImKvS18Ft5ypkuHqKo=; b=Ctoge73qewfatKl+O3Ght2qED3joRNXkyMGnANNbMGXJoNoFbcDppV7LNjkP/TNHlA ShZMS/i+f0V2EQFmSp/zRfVbtCVbhun1X5bBgFgbxv9E8pd1OdZoCIYgw/BTMtKlh/Dr NbyDzoFfAW8cQf8tqZ6iU2Nuc71BfNyCQJQC8= 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:user-agent; bh=zgoeSxe5mtUlsZsWEbnATz+W4ImKvS18Ft5ypkuHqKo=; b=pM5nGtAx9NhewHfFJ9aMxWYp7WBHq7MUKLg1pO8E4UMPhA1M9xHcswHF5adnGXGs7H tFh96aoXHJ1Fnvr7XoL6BsSYfxUQb/QzY8xLvnwS+hTQq/WowuhsmX7mIaXCuh8Gh13+ h0ywlpEibba+0y9cipanzPT3HBWGcgv171PgAXpLWFw+1+ezrU+AZRwqedrYKP/MPS+r tEy8Z6D/e6Fa7I513uwmrqLF56N2AtKC08qnb70KFJGZumHR/AypNaCNvvmx6MiUQecE huuAYANXJ1bSjtNEUXg7jAwzQTgRbOZTPdgMc7Xrizutim5n2D6L6KI4hDAs9t+ffUdC zk5w== X-Gm-Message-State: AA+aEWbwVXxbkUskO5Y4WyjF57ZWn8JjwxIEgD0NQygVTJ2uHIPMQ4xF oklieDg3Lr8mkSp5Qjm9HPPIlA== X-Google-Smtp-Source: AFSGD/UWmJzwTz4BE3RqDnVnlVm93grGI6k6XBgM5bjNy52u1bRHGCUWmyq/jObUmYJnilGMBTqrSA== X-Received: by 2002:a62:8893:: with SMTP id l141mr469240pfd.1.1545355279300; Thu, 20 Dec 2018 17:21:19 -0800 (PST) Received: from google.com ([2620:15c:202:1:534:b7c0:a63c:460c]) by smtp.gmail.com with ESMTPSA id z8sm31006615pgg.62.2018.12.20.17.21.18 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Thu, 20 Dec 2018 17:21:18 -0800 (PST) Date: Thu, 20 Dec 2018 17:21:16 -0800 From: Brian Norris To: Evan Green Cc: Andy Gross , Bjorn Andersson , Ben Chan , linux-arm-msm@vger.kernel.org, David Brown , linux-kernel@vger.kernel.org Subject: Re: [PATCH v1 2/2] soc: qcom: rmtfs-mem: Make sysfs attributes world-readable Message-ID: <20181221012115.GB189656@google.com> References: <20181218000834.201748-1-evgreen@chromium.org> <20181218000834.201748-3-evgreen@chromium.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181218000834.201748-3-evgreen@chromium.org> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Dec 17, 2018 at 04:08:34PM -0800, Evan Green wrote: > In order to run an rmtfs daemon as an unprivileged user, that user would > need access to the phys_addr and size sysfs attributes. Sharing these > attributes with unprivileged users doesn't really leak anything > sensitive, since if you have access to physical memory, the jig is > up anyway. > > Make those attributes readable by all. > > Signed-off-by: Evan Green > --- Seems fine to me. Reviewed-by: Brian Norris > > drivers/soc/qcom/rmtfs_mem.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/drivers/soc/qcom/rmtfs_mem.c b/drivers/soc/qcom/rmtfs_mem.c > index 0bf800ee2a978..4eeb9f02e7889 100644 > --- a/drivers/soc/qcom/rmtfs_mem.c > +++ b/drivers/soc/qcom/rmtfs_mem.c > @@ -45,9 +45,9 @@ static ssize_t qcom_rmtfs_mem_show(struct device *dev, > struct device_attribute *attr, > char *buf); > > -static DEVICE_ATTR(phys_addr, 0400, qcom_rmtfs_mem_show, NULL); > -static DEVICE_ATTR(size, 0400, qcom_rmtfs_mem_show, NULL); > -static DEVICE_ATTR(client_id, 0400, qcom_rmtfs_mem_show, NULL); > +static DEVICE_ATTR(phys_addr, 0444, qcom_rmtfs_mem_show, NULL); > +static DEVICE_ATTR(size, 0444, qcom_rmtfs_mem_show, NULL); > +static DEVICE_ATTR(client_id, 0444, qcom_rmtfs_mem_show, NULL); > > static ssize_t qcom_rmtfs_mem_show(struct device *dev, > struct device_attribute *attr, > -- > 2.18.1 >