From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ursula Braun Subject: [PATCH net 1/1] net/smc: keep clcsock reference in smc_tcp_listen_work() Date: Wed, 25 Apr 2018 12:48:58 +0200 Message-ID: <20180425104858.48953-1-ubraun@linux.ibm.com> Cc: netdev@vger.kernel.org, linux-s390@vger.kernel.org, schwidefsky@de.ibm.com, heiko.carstens@de.ibm.com, raspl@linux.vnet.ibm.com, ubraun@linux.vnet.ibm.com To: davem@davemloft.net Return-path: Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:50954 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1754470AbeDYKtM (ORCPT ); Wed, 25 Apr 2018 06:49:12 -0400 Received: from pps.filterd (m0098413.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.22/8.16.0.22) with SMTP id w3PAnAZO067784 for ; Wed, 25 Apr 2018 06:49:11 -0400 Received: from e06smtp10.uk.ibm.com (e06smtp10.uk.ibm.com [195.75.94.106]) by mx0b-001b2d01.pphosted.com with ESMTP id 2hjnjxfknh-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Wed, 25 Apr 2018 06:49:11 -0400 Received: from localhost by e06smtp10.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Wed, 25 Apr 2018 11:49:07 +0100 Sender: netdev-owner@vger.kernel.org List-ID: The internal CLC socket should exist till the SMC-socket is released. Function tcp_listen_worker() releases the internal CLC socket of a listen socket, if an smc_close_active() is called. This function is called for the final release(), but it is called for shutdown SHUT_RDWR as well. This opens a door for protection faults, if socket calls using the internal CLC socket are called for a shutdown listen socket. With the changes of commit 3d502067599f ("net/smc: simplify wait when closing listen socket") there is no need anymore to release the internal CLC socket in function tcp_listen_worker((). It is sufficient to release it in smc_release(). Fixes: 127f49705823 ("net/smc: release clcsock from tcp_listen_worker") Signed-off-by: Ursula Braun Reported-by: syzbot+9045fc589fcd196ef522@syzkaller.appspotmail.com Reported-by: syzbot+28a2c86cf19c81d871fa@syzkaller.appspotmail.com Reported-by: syzbot+9605e6cace1b5efd4a0a@syzkaller.appspotmail.com Reported-by: syzbot+cf9012c597c8379d535c@syzkaller.appspotmail.com --- net/smc/af_smc.c | 4 ---- 1 file changed, 4 deletions(-) diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c index f5d4b69dbabc..4470501374bf 100644 --- a/net/smc/af_smc.c +++ b/net/smc/af_smc.c @@ -978,10 +978,6 @@ static void smc_tcp_listen_work(struct work_struct *work) } out: - if (lsmc->clcsock) { - sock_release(lsmc->clcsock); - lsmc->clcsock = NULL; - } release_sock(lsk); sock_put(&lsmc->sk); /* sock_hold in smc_listen */ } -- 2.13.5