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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5ADEEC433F5 for ; Tue, 17 May 2022 13:05:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1347021AbiEQNFg (ORCPT ); Tue, 17 May 2022 09:05:36 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36894 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1347346AbiEQNE6 (ORCPT ); Tue, 17 May 2022 09:04:58 -0400 Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D75FC4EA01; Tue, 17 May 2022 06:03:46 -0700 (PDT) Received: from dggpemm500021.china.huawei.com (unknown [172.30.72.53]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4L2br036l8zgYFS; Tue, 17 May 2022 21:02:24 +0800 (CST) Received: from dggpemm500007.china.huawei.com (7.185.36.183) by dggpemm500021.china.huawei.com (7.185.36.109) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Tue, 17 May 2022 21:03:44 +0800 Received: from [10.174.178.174] (10.174.178.174) by dggpemm500007.china.huawei.com (7.185.36.183) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Tue, 17 May 2022 21:03:44 +0800 Subject: Re: [PATCH -next] drivers: w1: use kfree_sensitive() To: Greg KH CC: , , , , References: <20220511064954.3401381-1-yangyingliang@huawei.com> <2cf24169-ea56-9c72-fa95-a1e6625c8545@huawei.com> From: Yang Yingliang Message-ID: <16959408-3e91-774d-484f-508caff1f8f7@huawei.com> Date: Tue, 17 May 2022 21:03:43 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:68.0) Gecko/20100101 Thunderbird/68.7.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset="utf-8"; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US X-Originating-IP: [10.174.178.174] X-ClientProxiedBy: dggems703-chm.china.huawei.com (10.3.19.180) To dggpemm500007.china.huawei.com (7.185.36.183) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2022/5/17 18:18, Greg KH wrote: > On Wed, May 11, 2022 at 03:25:52PM +0800, Yang Yingliang wrote: >> Hi, >> >> On 2022/5/11 14:45, Greg KH wrote: >>> On Wed, May 11, 2022 at 02:49:54PM +0800, Yang Yingliang wrote: >>>> Use kfree_sensitive() instead of open-coding it. >>>> >>>> Signed-off-by: Yang Yingliang >>>> --- >>>> drivers/w1/w1.c | 3 +-- >>>> 1 file changed, 1 insertion(+), 2 deletions(-) >>>> >>>> diff --git a/drivers/w1/w1.c b/drivers/w1/w1.c >>>> index f2ae2e563dc5..a0a6c3c739d9 100644 >>>> --- a/drivers/w1/w1.c >>>> +++ b/drivers/w1/w1.c >>>> @@ -73,8 +73,7 @@ static void w1_master_release(struct device *dev) >>>> struct w1_master *md = dev_to_w1_master(dev); >>>> dev_dbg(dev, "%s: Releasing %s.\n", __func__, md->name); >>>> - memset(md, 0, sizeof(struct w1_master) + sizeof(struct w1_bus_master)); >>>> - kfree(md); >>>> + kfree_sensitive(md); >>> Does this actually change anything? Why is the memset being called here >>> at all? >> It's no functional change and I got this by >> scripts/coccinelle/api/kfree_sensitive.cocci. >> I'm not sure why using memset() here. > I think the memset() can just be dropped. Can you make that change and > test it to verify it still works properly with that change? I can make change and send a patch for this, but I don't have device to test it. > > thanks, > > greg k-h > .