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=-10.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 7C5EAC433DF for ; Mon, 3 Aug 2020 08:13:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4CF2520678 for ; Mon, 3 Aug 2020 08:13:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1596442406; bh=Z3NZjfOhC3W1xjPseRYdO9bMJt2sAUY1ZaWIH+d8s3E=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=T80+sd4sPi2T0kxJhYTF8Ss6SZpOxzJLDOtY57I08NdVtzlpaS0K1Z8aVlc/Z0muS 6ymFrNCsWn2RYK+TkyFmA1I4fsK7reUZyll2uP5VjoAPo2aRU2Ew051SEQFmLjj4Ij bYNkxanzmeJFXprZs9yEMmfr+Mvy1YapR04bM4YU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725991AbgHCINZ (ORCPT ); Mon, 3 Aug 2020 04:13:25 -0400 Received: from mail.kernel.org ([198.145.29.99]:58582 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725806AbgHCINZ (ORCPT ); Mon, 3 Aug 2020 04:13:25 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 85BAC2065E; Mon, 3 Aug 2020 08:13:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1596442404; bh=Z3NZjfOhC3W1xjPseRYdO9bMJt2sAUY1ZaWIH+d8s3E=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=ZBQ3T5G6cVuW2XdvkWSc8FKh7JkTjwtGogcsfy4HRaitDqgYtSBLD3G5CyjW5nUlY rkib/sFZ6aeA7DqVjCX+odRY9EZrf0omTkTtF216Y0O/vwlywmTs9txgx1fWSY2d6o OsbZ3hrWfMn/QGwF4kS/tivppXPWerTqRiA9f260= Date: Mon, 3 Aug 2020 10:13:07 +0200 From: Greg Kroah-Hartman To: Andy Shevchenko Cc: linux-kernel@vger.kernel.org, "Rafael J. Wysocki" , Qu Wenruo , Heikki Krogerus Subject: Re: [PATCH v1] kobject: Restore old behaviour of kobject_del(NULL) Message-ID: <20200803081307.GB493272@kroah.com> References: <20200803073859.43664-1-andriy.shevchenko@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200803073859.43664-1-andriy.shevchenko@linux.intel.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Aug 03, 2020 at 10:38:59AM +0300, Andy Shevchenko wrote: > The commit 079ad2fb4bf9 ("kobject: Avoid premature parent object freeing in > kobject_cleanup()") inadvertently dropped a possibility to call kobject_del() > with NULL pointer. Restore the old behaviour. > > Fixes: 079ad2fb4bf9 ("kobject: Avoid premature parent object freeing in kobject_cleanup()") > Reported-by: Qu Wenruo > Cc: Heikki Krogerus > Signed-off-by: Andy Shevchenko > --- > lib/kobject.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/lib/kobject.c b/lib/kobject.c > index 3afb939f2a1c..f5f5273031d2 100644 > --- a/lib/kobject.c > +++ b/lib/kobject.c > @@ -637,7 +637,7 @@ static void __kobject_del(struct kobject *kobj) > */ > void kobject_del(struct kobject *kobj) > { > - struct kobject *parent = kobj->parent; > + struct kobject *parent = kobj ? kobj->parent : NULL; I _HATE_ "? :" logic, and it obscures the logic in this function, just add a simple: if (!kobj) return; to this function please. thanks, greg k-h