From patchwork Mon Mar 6 04:08:48 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "D. Wythe" X-Patchwork-Id: 13160427 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 023E4C74A5B for ; Mon, 6 Mar 2023 04:10:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229750AbjCFEKD (ORCPT ); Sun, 5 Mar 2023 23:10:03 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42042 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229663AbjCFEJP (ORCPT ); Sun, 5 Mar 2023 23:09:15 -0500 Received: from out30-133.freemail.mail.aliyun.com (out30-133.freemail.mail.aliyun.com [115.124.30.133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 01F2FC67E; Sun, 5 Mar 2023 20:08:57 -0800 (PST) X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R451e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=ay29a033018046059;MF=alibuda@linux.alibaba.com;NM=1;PH=DS;RN=8;SR=0;TI=SMTPD_---0Vd8X437_1678075728; Received: from j66a10360.sqa.eu95.tbsite.net(mailfrom:alibuda@linux.alibaba.com fp:SMTPD_---0Vd8X437_1678075728) by smtp.aliyun-inc.com; Mon, 06 Mar 2023 12:08:55 +0800 From: "D. Wythe" To: kgraul@linux.ibm.com, wenjia@linux.ibm.com, jaka@linux.ibm.com Cc: kuba@kernel.org, davem@davemloft.net, netdev@vger.kernel.org, linux-s390@vger.kernel.org, linux-rdma@vger.kernel.org Subject: [PATCH net] net/smc: fix fallback failed while sendmsg with fastopen Date: Mon, 6 Mar 2023 12:08:48 +0800 Message-Id: <1678075728-18812-1-git-send-email-alibuda@linux.alibaba.com> X-Mailer: git-send-email 1.8.3.1 Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org From: "D. Wythe" Before determining whether the msg has unsupported options, it has been prematurely terminated by the wrong status check. For the application, the general method of MSG_FASTOPEN likes fd = socket(...) /* rather than connect */ sendto(fd, data, len, MSG_FASTOPEN) Hence, We need to check the flag before state check, because the sock state here is always SMC_INIT when applications tries MSG_FASTOPEN. Once we found unsupported options, fallback it to TCP. Fixes: ee9dfbef02d1 ("net/smc: handle sockopts forcing fallback") Signed-off-by: D. Wythe Signed-off-by: Simon Horman --- net/smc/af_smc.c | 26 ++++++++++++++++---------- 1 file changed, 16 insertions(+), 10 deletions(-) diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c index b233c94..fd80879 100644 --- a/net/smc/af_smc.c +++ b/net/smc/af_smc.c @@ -2662,24 +2662,30 @@ static int smc_sendmsg(struct socket *sock, struct msghdr *msg, size_t len) int rc = -EPIPE; smc = smc_sk(sk); - lock_sock(sk); - if ((sk->sk_state != SMC_ACTIVE) && - (sk->sk_state != SMC_APPCLOSEWAIT1) && - (sk->sk_state != SMC_INIT)) - goto out; + /* SMC do not support connect with fastopen */ if (msg->msg_flags & MSG_FASTOPEN) { + rc = -EINVAL; + lock_sock(sk); + /* not perform connect yet, fallback it */ if (sk->sk_state == SMC_INIT && !smc->connect_nonblock) { rc = smc_switch_to_fallback(smc, SMC_CLC_DECL_OPTUNSUPP); - if (rc) - goto out; - } else { - rc = -EINVAL; - goto out; + /* fallback success */ + if (rc == 0) + goto fallback; /* with sock lock hold */ } + release_sock(sk); + return rc; } + lock_sock(sk); + if (sk->sk_state != SMC_ACTIVE && + sk->sk_state != SMC_APPCLOSEWAIT1 && + sk->sk_state != SMC_INIT) + goto out; + if (smc->use_fallback) { +fallback: rc = smc->clcsock->ops->sendmsg(smc->clcsock, msg, len); } else { rc = smc_tx_sendmsg(smc, msg, len);