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 6508DCDB482 for ; Wed, 11 Oct 2023 20:31:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233360AbjJKUbr (ORCPT ); Wed, 11 Oct 2023 16:31:47 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54526 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233427AbjJKUbq (ORCPT ); Wed, 11 Oct 2023 16:31:46 -0400 Received: from mx0b-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com [148.163.158.5]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2274091; Wed, 11 Oct 2023 13:31:45 -0700 (PDT) Received: from pps.filterd (m0353723.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 39BKErVt006601; Wed, 11 Oct 2023 20:31:40 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=message-id : date : mime-version : subject : to : cc : references : from : in-reply-to : content-type : content-transfer-encoding; s=pp1; bh=Wz952yxI+W2urZ0VD9E40vDqhU0tEtGlzr5j5jcMADw=; b=X424MufFhCuSu0IZiWUXDgA0yr1GP+uhey6nLJEXwzaaFwB5jC3dD75dpbCVSzjQAtd8 si7oeoriz9bNTcLZLjrnnKNelnItVoKzGaAcrS5PIMqPev4coNSQLx7kOIbVLGskDXvE emagMB6svEt6hhF6DDCWORfZtY36yLH2fmXTJGxeOTEbLOnAyfHsnGCp7RNlAjhmuZRU anODlyEx8hGgMzGc3kKiyl+iZmj4HwiwjYTL+28daFOc4jJQsdE+YFLWsO9UPF1yJ+nM uSGmrzCkM/m4sHKVBE6n/YTC7ynRrDBU5OJLrpjrzusiraUWpaDaqyhusppnwjvPx38d oQ== Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 3tp2jugjac-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 11 Oct 2023 20:31:39 +0000 Received: from m0353723.ppops.net (m0353723.ppops.net [127.0.0.1]) by pps.reinject (8.17.1.5/8.17.1.5) with ESMTP id 39BKPNL5012901; Wed, 11 Oct 2023 20:31:39 GMT Received: from ppma22.wdc07v.mail.ibm.com (5c.69.3da9.ip4.static.sl-reverse.com [169.61.105.92]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 3tp2jugja1-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 11 Oct 2023 20:31:39 +0000 Received: from pps.filterd (ppma22.wdc07v.mail.ibm.com [127.0.0.1]) by ppma22.wdc07v.mail.ibm.com (8.17.1.19/8.17.1.19) with ESMTP id 39BILYbR028188; Wed, 11 Oct 2023 20:31:38 GMT Received: from smtprelay05.wdc07v.mail.ibm.com ([172.16.1.72]) by ppma22.wdc07v.mail.ibm.com (PPS) with ESMTPS id 3tkj1yb0f4-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 11 Oct 2023 20:31:38 +0000 Received: from smtpav01.wdc07v.mail.ibm.com (smtpav01.wdc07v.mail.ibm.com [10.39.53.228]) by smtprelay05.wdc07v.mail.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 39BKVbUR27394682 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 11 Oct 2023 20:31:37 GMT Received: from smtpav01.wdc07v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 42F5158059; Wed, 11 Oct 2023 20:31:37 +0000 (GMT) Received: from smtpav01.wdc07v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 870BC5804B; Wed, 11 Oct 2023 20:31:35 +0000 (GMT) Received: from [9.171.29.13] (unknown [9.171.29.13]) by smtpav01.wdc07v.mail.ibm.com (Postfix) with ESMTP; Wed, 11 Oct 2023 20:31:35 +0000 (GMT) Message-ID: Date: Wed, 11 Oct 2023 22:31:34 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH net 1/5] net/smc: fix dangling sock under state SMC_APPFINCLOSEWAIT Content-Language: en-GB To: "D. Wythe" , kgraul@linux.ibm.com, jaka@linux.ibm.com, wintera@linux.ibm.com Cc: kuba@kernel.org, davem@davemloft.net, netdev@vger.kernel.org, linux-s390@vger.kernel.org, linux-rdma@vger.kernel.org References: <1697009600-22367-1-git-send-email-alibuda@linux.alibaba.com> <1697009600-22367-2-git-send-email-alibuda@linux.alibaba.com> From: Wenjia Zhang In-Reply-To: <1697009600-22367-2-git-send-email-alibuda@linux.alibaba.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 X-Proofpoint-ORIG-GUID: GyiSunecSvoAHVnxNuwSVWlrlOcK-b6i X-Proofpoint-GUID: JqdmAmwyOrN2dAHJjyNZlq23tbcQKitD X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.267,Aquarius:18.0.980,Hydra:6.0.619,FMLib:17.11.176.26 definitions=2023-10-11_15,2023-10-11_01,2023-05-22_02 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 suspectscore=0 mlxlogscore=999 clxscore=1015 priorityscore=1501 adultscore=0 phishscore=0 bulkscore=0 impostorscore=0 spamscore=0 lowpriorityscore=0 mlxscore=0 malwarescore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2309180000 definitions=main-2310110179 Precedence: bulk List-ID: X-Mailing-List: linux-s390@vger.kernel.org On 11.10.23 09:33, D. Wythe wrote: > From: "D. Wythe" > > Considering scenario: > > smc_cdc_rx_handler_rwwi > __smc_release > sock_set_flag > smc_close_active() > sock_set_flag > > __set_bit(DEAD) __set_bit(DONE) > > Dues to __set_bit is not atomic, the DEAD or DONE might be lost. > if the DEAD flag lost, the state SMC_CLOSED will be never be reached > in smc_close_passive_work: > > if (sock_flag(sk, SOCK_DEAD) && > smc_close_sent_any_close(conn)) { > sk->sk_state = SMC_CLOSED; > } else { > /* just shutdown, but not yet closed locally */ > sk->sk_state = SMC_APPFINCLOSEWAIT; > } > > Replace sock_set_flags or __set_bit to set_bit will fix this problem. > Since set_bit is atomic. > I didn't really understand the scenario. What is smc_cdc_rx_handler_rwwi()? What does it do? Don't it get the lock during the runtime? > Signed-off-by: D. Wythe > --- > net/smc/af_smc.c | 4 ++-- > net/smc/smc.h | 5 +++++ > net/smc/smc_cdc.c | 2 +- > net/smc/smc_close.c | 2 +- > 4 files changed, 9 insertions(+), 4 deletions(-) > > diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c > index bacdd97..5ad2a9f 100644 > --- a/net/smc/af_smc.c > +++ b/net/smc/af_smc.c > @@ -275,7 +275,7 @@ static int __smc_release(struct smc_sock *smc) > > if (!smc->use_fallback) { > rc = smc_close_active(smc); > - sock_set_flag(sk, SOCK_DEAD); > + smc_sock_set_flag(sk, SOCK_DEAD); > sk->sk_shutdown |= SHUTDOWN_MASK; > } else { > if (sk->sk_state != SMC_CLOSED) { > @@ -1742,7 +1742,7 @@ static int smc_clcsock_accept(struct smc_sock *lsmc, struct smc_sock **new_smc) > if (new_clcsock) > sock_release(new_clcsock); > new_sk->sk_state = SMC_CLOSED; > - sock_set_flag(new_sk, SOCK_DEAD); > + smc_sock_set_flag(new_sk, SOCK_DEAD); > sock_put(new_sk); /* final */ > *new_smc = NULL; > goto out; > diff --git a/net/smc/smc.h b/net/smc/smc.h > index 24745fd..e377980 100644 > --- a/net/smc/smc.h > +++ b/net/smc/smc.h > @@ -377,4 +377,9 @@ void smc_fill_gid_list(struct smc_link_group *lgr, > int smc_nl_enable_hs_limitation(struct sk_buff *skb, struct genl_info *info); > int smc_nl_disable_hs_limitation(struct sk_buff *skb, struct genl_info *info); > > +static inline void smc_sock_set_flag(struct sock *sk, enum sock_flags flag) > +{ > + set_bit(flag, &sk->sk_flags); > +} > + > #endif /* __SMC_H */ > diff --git a/net/smc/smc_cdc.c b/net/smc/smc_cdc.c > index 89105e9..01bdb79 100644 > --- a/net/smc/smc_cdc.c > +++ b/net/smc/smc_cdc.c > @@ -385,7 +385,7 @@ static void smc_cdc_msg_recv_action(struct smc_sock *smc, > smc->sk.sk_shutdown |= RCV_SHUTDOWN; > if (smc->clcsock && smc->clcsock->sk) > smc->clcsock->sk->sk_shutdown |= RCV_SHUTDOWN; > - sock_set_flag(&smc->sk, SOCK_DONE); > + smc_sock_set_flag(&smc->sk, SOCK_DONE); > sock_hold(&smc->sk); /* sock_put in close_work */ > if (!queue_work(smc_close_wq, &conn->close_work)) > sock_put(&smc->sk); > diff --git a/net/smc/smc_close.c b/net/smc/smc_close.c > index dbdf03e..449ef45 100644 > --- a/net/smc/smc_close.c > +++ b/net/smc/smc_close.c > @@ -173,7 +173,7 @@ void smc_close_active_abort(struct smc_sock *smc) > break; > } > > - sock_set_flag(sk, SOCK_DEAD); > + smc_sock_set_flag(sk, SOCK_DEAD); > sk->sk_state_change(sk); > > if (release_clcsock) {