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 159F8C433EF for ; Tue, 1 Mar 2022 12:55:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234866AbiCAM4X (ORCPT ); Tue, 1 Mar 2022 07:56:23 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34234 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230415AbiCAM4W (ORCPT ); Tue, 1 Mar 2022 07:56:22 -0500 Received: from gandalf.ozlabs.org (gandalf.ozlabs.org [150.107.74.76]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7CBF78A318 for ; Tue, 1 Mar 2022 04:55:40 -0800 (PST) Received: from authenticated.ozlabs.org (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by mail.ozlabs.org (Postfix) with ESMTPSA id 4K7HKk1xG8z4xPt; Tue, 1 Mar 2022 23:55:38 +1100 (AEDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ellerman.id.au; s=201909; t=1646139338; bh=3gAUw2bljeQgo+EIP3uDFWmam1knQZu7pffpGmaV4fk=; h=From:To:Cc:Subject:In-Reply-To:References:Date:From; b=dlVJsWZXk+G/5EIS6pOP76i9u12kyE3/AwRjYtkWQDUaSChKkxstgICysnR1WNgZi 7CrNqGb+0B5EdXQSh+3R7DzUA3c9CiOXS0Ozj5tDNG2V/e/ikkI83Ngdq/ndgw/TZQ 7yBJwtiN3X6oP638JzaoGKtuLi/MwoiZYogkr+9sLMKkiEL5waISY3OIbY6WdEX7QL YTgis/hp3vihz82rnv2XaKrdagoQDFgQbv3vmvkv33Ard89MNdONaFr9K/IeUu8cTf nrC6NDS5xQ1EPCapfFcHV6tZ0Zp/dsam/3TJ0jzg0BeBvZkoHuZ5gvEWWl0Wu83saW 04qgfukwQbWQQ== From: Michael Ellerman To: Hangyu Hua , benh@kernel.crashing.org, paulus@samba.org Cc: linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, Hangyu Hua Subject: Re: [PATCH] powerpc: kernel: fix a refcount leak in format_show() In-Reply-To: <20220228091103.39749-1-hbh25y@gmail.com> References: <20220228091103.39749-1-hbh25y@gmail.com> Date: Tue, 01 Mar 2022 23:55:35 +1100 Message-ID: <87o82pomrc.fsf@mpe.ellerman.id.au> MIME-Version: 1.0 Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hangyu Hua writes: > node needs to be dropped when of_property_read_string fails. So an earlier call > to of_node_put is required here. That's true but ... > diff --git a/arch/powerpc/kernel/secvar-sysfs.c b/arch/powerpc/kernel/secvar-sysfs.c > index a0a78aba2083..cd0fa7028d86 100644 > --- a/arch/powerpc/kernel/secvar-sysfs.c > +++ b/arch/powerpc/kernel/secvar-sysfs.c > @@ -30,13 +30,12 @@ static ssize_t format_show(struct kobject *kobj, struct kobj_attribute *attr, > return -ENODEV; There's also a reference leak there ^ So if you're going to touch this code I'd like you to fix both reference leaks in a single patch please. Having the error cases set rc and then goto "out" which does the of_node_put() is the obvious solution I think. cheers > rc = of_property_read_string(node, "format", &format); > + of_node_put(node); > if (rc) > return rc; > > rc = sprintf(buf, "%s\n", format); > > - of_node_put(node); > - > return rc; > } > > -- > 2.25.1