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=-17.6 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, UNPARSEABLE_RELAY,USER_AGENT_SANE_1 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 F0E7AC2B9F7 for ; Fri, 28 May 2021 13:34:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B7348613E5 for ; Fri, 28 May 2021 13:34:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235607AbhE1Nf5 (ORCPT ); Fri, 28 May 2021 09:35:57 -0400 Received: from mx0b-00069f02.pphosted.com ([205.220.177.32]:17450 "EHLO mx0b-00069f02.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229653AbhE1Nft (ORCPT ); Fri, 28 May 2021 09:35:49 -0400 Received: from pps.filterd (m0246630.ppops.net [127.0.0.1]) by mx0b-00069f02.pphosted.com (8.16.0.43/8.16.0.43) with SMTP id 14SDKU0Q001860; Fri, 28 May 2021 13:33:27 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=date : from : to : cc : subject : message-id : references : mime-version : content-type : in-reply-to; s=corp-2020-01-29; bh=HLUSfFNsvepNfOshN0c8ooQ73thlVw/e2Bq6VxGepJc=; b=MGZhgWhg95roXsJDEqHHYCO9dXvFbeEACtvc4AUZmGaH/OSA0LptpxmiGBe9HiKzfOuB YeqeRyzqFi25xsZT5aQ3FOhnWGlLt5uF5NloiM9oXt+ULCe8FAdpqzrntKJgscO9QCOH YDl9a1v08Bv1PpLyUKvafDTaM4Vov8lOuuHrbMftKkgASkEFVfs4aT6U02D2CDAFhC3o kdKM8/mz3eYEV16T+dEpVDrW3rKwyopsI86aaD4ra84Pv1UVUv2ELT77xelkgdmdI5cb CsQdHYjjXtv1cEkjK1TWIANUF2JFS73YioYCpsa/1SXfwRMYXPKfRqLmSsjTWisDGZq7 PA== Received: from oracle.com (aserp3020.oracle.com [141.146.126.70]) by mx0b-00069f02.pphosted.com with ESMTP id 38sn3yrwmj-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 28 May 2021 13:33:27 +0000 Received: from aserp3020.oracle.com (aserp3020.oracle.com [127.0.0.1]) by pps.podrdrct (8.16.0.36/8.16.0.36) with SMTP id 14SDLxuX117567; Fri, 28 May 2021 13:33:26 GMT Received: from pps.reinject (localhost [127.0.0.1]) by aserp3020.oracle.com with ESMTP id 38rehkyxhp-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 28 May 2021 13:33:26 +0000 Received: from aserp3020.oracle.com (aserp3020.oracle.com [127.0.0.1]) by pps.reinject (8.16.0.36/8.16.0.36) with SMTP id 14SDXPtD194449; Fri, 28 May 2021 13:33:25 GMT Received: from aserv0122.oracle.com (aserv0122.oracle.com [141.146.126.236]) by aserp3020.oracle.com with ESMTP id 38rehkyxh4-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 28 May 2021 13:33:25 +0000 Received: from abhmp0019.oracle.com (abhmp0019.oracle.com [141.146.116.25]) by aserv0122.oracle.com (8.14.4/8.14.4) with ESMTP id 14SDXISv026221; Fri, 28 May 2021 13:33:23 GMT Received: from kadam (/41.212.42.34) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Fri, 28 May 2021 06:33:17 -0700 Date: Fri, 28 May 2021 16:33:09 +0300 From: Dan Carpenter To: Dongliang Mu Cc: perex@perex.cz, tiwai@suse.com, alsa-devel@alsa-project.org, linux-kernel@vger.kernel.org, syzbot+08a7d8b51ea048a74ffb@syzkaller.appspotmail.com Subject: Re: [PATCH] ALSA: control led: fix memory leak in snd_ctl_led_register Message-ID: <20210528133309.GR24442@kadam> References: <20210528131757.2269989-1-mudongliangabcd@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210528131757.2269989-1-mudongliangabcd@gmail.com> User-Agent: Mutt/1.9.4 (2018-02-28) X-Proofpoint-GUID: UVSJdCaZHlkVip_h0yaymPkF8ZNnex7o X-Proofpoint-ORIG-GUID: UVSJdCaZHlkVip_h0yaymPkF8ZNnex7o Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, May 28, 2021 at 09:17:57PM +0800, Dongliang Mu wrote: > The snd_ctl_led_sysfs_add and snd_ctl_led_sysfs_remove should contain > the refcount operations in pair. However, snd_ctl_led_sysfs_remove fails > to decrease the refcount to zero, which causes device_release never to > be invoked. This leads to memory leak to some resources, like struct > device_private. > > Fix this by calling put_device at the end of snd_ctl_led_sysfs_remove > > Reported-by: syzbot+08a7d8b51ea048a74ffb@syzkaller.appspotmail.com > Fixes: a135dfb5de1 ("ALSA: led control - add sysfs kcontrol LED marking layer") > Signed-off-by: Dongliang Mu > --- > sound/core/control_led.c | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/sound/core/control_led.c b/sound/core/control_led.c > index 25f57c14f294..fff2688b5019 100644 > --- a/sound/core/control_led.c > +++ b/sound/core/control_led.c > @@ -371,6 +371,10 @@ static void snd_ctl_led_disconnect(struct snd_card *card) > snd_ctl_led_refresh(); > } > > +static void snd_ctl_led_release(struct device *dev) > +{ > +} Whatever you're trying to do, adding a dummy function is never the answer. regards, dan carpenter