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=-15.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, 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 952F1C64E7A for ; Wed, 2 Dec 2020 02:05:37 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id AB40821D7E for ; Wed, 2 Dec 2020 02:05:36 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org AB40821D7E Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=huawei.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:46512 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kkHWR-0003Cn-KI for qemu-devel@archiver.kernel.org; Tue, 01 Dec 2020 21:05:35 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:41908) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kkHTm-00024r-UR; Tue, 01 Dec 2020 21:02:50 -0500 Received: from szxga06-in.huawei.com ([45.249.212.32]:2106) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kkHTg-0003BD-Er; Tue, 01 Dec 2020 21:02:49 -0500 Received: from DGGEMS403-HUB.china.huawei.com (unknown [172.30.72.60]) by szxga06-in.huawei.com (SkyGuard) with ESMTP id 4Cm2K95rZmzhlSF; Wed, 2 Dec 2020 10:02:05 +0800 (CST) Received: from [10.174.187.138] (10.174.187.138) by DGGEMS403-HUB.china.huawei.com (10.3.19.203) with Microsoft SMTP Server id 14.3.487.0; Wed, 2 Dec 2020 10:02:18 +0800 Message-ID: <5FC6F5AB.30300@huawei.com> Date: Wed, 2 Dec 2020 10:02:19 +0800 From: Alex Chen User-Agent: Mozilla/5.0 (Windows NT 6.2; WOW64; rv:17.0) Gecko/20130509 Thunderbird/17.0.6 MIME-Version: 1.0 To: Eric Blake Subject: Re: [PATCH] qemu-nbd: Fix a memleak in nbd_client_thread() References: <20201201061349.110262-1-alex.chen@huawei.com> In-Reply-To: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.174.187.138] X-CFilter-Loop: Reflected Received-SPF: pass client-ip=45.249.212.32; envelope-from=alex.chen@huawei.com; helo=szxga06-in.huawei.com X-Spam_score_int: -41 X-Spam_score: -4.2 X-Spam_bar: ---- X-Spam_report: (-4.2 / 5.0 requ) BAYES_00=-1.9, NICE_REPLY_A=-0.001, RCVD_IN_DNSWL_MED=-2.3, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: qemu-trivial@nongnu.org, qemu-devel@nongnu.org, qemu-block@nongnu.org, zhang.zhanghailiang@huawei.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On 2020/12/2 4:15, Eric Blake wrote: > On 12/1/20 12:13 AM, Alex Chen wrote: >> When the qio_channel_socket_connect_sync() fails >> we should goto 'out_socket' label to free the 'sioc' instead of >> goto 'out' label. >> In addition, now the 'out' label is useless, delete it. >> >> Reported-by: Euler Robot >> Signed-off-by: Alex Chen >> --- >> qemu-nbd.c | 3 +-- >> 1 file changed, 1 insertion(+), 2 deletions(-) >> >> diff --git a/qemu-nbd.c b/qemu-nbd.c >> index 47587a709e..643b0777c0 100644 >> --- a/qemu-nbd.c >> +++ b/qemu-nbd.c >> @@ -275,7 +275,7 @@ static void *nbd_client_thread(void *arg) >> saddr, >> &local_error) < 0) { >> error_report_err(local_error); >> - goto out; >> + goto out_socket; >> } >> >> ret = nbd_receive_negotiate(NULL, QIO_CHANNEL(sioc), >> @@ -325,7 +325,6 @@ out_fd: >> close(fd); >> out_socket: >> object_unref(OBJECT(sioc)); >> -out: >> g_free(info.name); >> kill(getpid(), SIGTERM); >> return (void *) EXIT_FAILURE; >> > > While the patch looks correct, we have a lot of duplication. Simpler > might be a solution with only one exit label altogether: > Thanks for your review, I will modify the patch and send patch v2 according to your suggestion. BTW, do I need to split this patch into two patches, one to solve the memleak and the other to optimizes the redundant code? Thanks, Alex > diff --git i/qemu-nbd.c w/qemu-nbd.c > index a7075c5419d7..d7bdcd0011ba 100644 > --- i/qemu-nbd.c > +++ w/qemu-nbd.c > @@ -265,8 +265,8 @@ static void *nbd_client_thread(void *arg) > char *device = arg; > NBDExportInfo info = { .request_sizes = false, .name = g_strdup("") }; > QIOChannelSocket *sioc; > - int fd; > - int ret; > + int fd = -1; > + int ret = EXIT_FAILURE; > pthread_t show_parts_thread; > Error *local_error = NULL; > > @@ -278,26 +278,24 @@ static void *nbd_client_thread(void *arg) > goto out; > } > > - ret = nbd_receive_negotiate(NULL, QIO_CHANNEL(sioc), > - NULL, NULL, NULL, &info, &local_error); > - if (ret < 0) { > + if (nbd_receive_negotiate(NULL, QIO_CHANNEL(sioc), > + NULL, NULL, NULL, &info, &local_error) < 0) { > if (local_error) { > error_report_err(local_error); > } > - goto out_socket; > + goto out; > } > > fd = open(device, O_RDWR); > if (fd < 0) { > /* Linux-only, we can use %m in printf. */ > error_report("Failed to open %s: %m", device); > - goto out_socket; > + goto out; > } > > - ret = nbd_init(fd, sioc, &info, &local_error); > - if (ret < 0) { > + if (nbd_init(fd, sioc, &info, &local_error) < 0) { > error_report_err(local_error); > - goto out_fd; > + goto out; > } > > /* update partition table */ > @@ -311,24 +309,18 @@ static void *nbd_client_thread(void *arg) > dup2(STDOUT_FILENO, STDERR_FILENO); > } > > - ret = nbd_client(fd); > - if (ret) { > - goto out_fd; > + if (nbd_client(fd) == 0) { > + ret = EXIT_SUCCESS; > } > - close(fd); > - object_unref(OBJECT(sioc)); > - g_free(info.name); > - kill(getpid(), SIGTERM); > - return (void *) EXIT_SUCCESS; > > -out_fd: > - close(fd); > -out_socket: > + out: > + if (fd >= 0) { > + close(fd); > + } > object_unref(OBJECT(sioc)); > -out: > g_free(info.name); > kill(getpid(), SIGTERM); > - return (void *) EXIT_FAILURE; > + return (void *) (intptr_t) ret; > } > #endif /* HAVE_NBD_DEVICE */ >