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 4B7C3C433F5 for ; Wed, 11 May 2022 10:06:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239783AbiEKKGp (ORCPT ); Wed, 11 May 2022 06:06:45 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37436 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239823AbiEKKFn (ORCPT ); Wed, 11 May 2022 06:05:43 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B205D62A3A; Wed, 11 May 2022 03:05:24 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 1FBEEB82161; Wed, 11 May 2022 10:05:23 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 446B4C340EB; Wed, 11 May 2022 10:05:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1652263521; bh=eN6tRaNsKdXJ5b2UYaX+XtTfVsjOULKf85SSpTbupxU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=aavEMBHUNy33lh4iB/6lVCkiD+LzZNAaGsRNCNw5nHRojoLcQ5jTGzCVX9nuA1/n9 M8IqNM+wkoIGFUISczX0KY8nhQLXnah43fX64CnGO0IUDeDJ/FY+UAESUFpSZleJEW IIDryw91pZlUFsdRaGaW9IUEHwyafwqMSkVQcZAk= Date: Wed, 11 May 2022 12:05:18 +0200 From: Greg KH To: Yang Yingliang Cc: linux-kernel@vger.kernel.org, linux-hwmon@vger.kernel.org, zbr@ioremap.net, jdelvare@suse.com, linux@roeck-us.net Subject: Re: [PATCH -next] drivers: w1: use kfree_sensitive() Message-ID: References: <20220511064954.3401381-1-yangyingliang@huawei.com> <2cf24169-ea56-9c72-fa95-a1e6625c8545@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <2cf24169-ea56-9c72-fa95-a1e6625c8545@huawei.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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. That's an odd rule, and as you can see here, not always correct or needed. > I'm not sure why using memset() here. Then let's not make this change without figuring that out first please. thanks, greg k-h