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=-18.8 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, USER_AGENT_GIT 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 847F7C4361B for ; Mon, 1 Mar 2021 18:54:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4883764DEE for ; Mon, 1 Mar 2021 18:54:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240665AbhCASxX (ORCPT ); Mon, 1 Mar 2021 13:53:23 -0500 Received: from mail.kernel.org ([198.145.29.99]:53936 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240421AbhCASqp (ORCPT ); Mon, 1 Mar 2021 13:46:45 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 7853264F45; Mon, 1 Mar 2021 17:14:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1614618851; bh=UDF5jyk/gV0RH6B4X9+TOSmZZHyWmpJTDx6OtgDFrbw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=zPaETHoe3fH9ggu/kvnGeFmVVKtOMEIY/35XsWnwuou6aG576AOcLf+4v9OkFJrQI 3Fwq3jKmi2kOthDdPkonhZwBlnXW0ktWJDhFx0Qo2+nWZdV5kwgZnpraH6ll1/0F1C VMSPuorHgmE2C1CEGOHPR2JQv+Olhz9YzV+7JGVg= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Elad Grupi , Sagi Grimberg , Christoph Hellwig , Sasha Levin Subject: [PATCH 5.10 241/663] nvmet-tcp: fix potential race of tcp socket closing accept_work Date: Mon, 1 Mar 2021 17:08:09 +0100 Message-Id: <20210301161153.745307078@linuxfoundation.org> X-Mailer: git-send-email 2.30.1 In-Reply-To: <20210301161141.760350206@linuxfoundation.org> References: <20210301161141.760350206@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Sagi Grimberg [ Upstream commit 0fbcfb089a3f2f2a731d01f0aec8f7697a849c28 ] When we accept a TCP connection and allocate an nvmet-tcp queue we should make sure not to fully establish it or reference it as the connection may be already closing, which triggers queue release work, which does not fence against queue establishment. In order to address such a race, we make sure to check the sk_state and contain the queue reference to be done underneath the sk_callback_lock such that the queue release work correctly fences against it. Fixes: 872d26a391da ("nvmet-tcp: add NVMe over TCP target driver") Reported-by: Elad Grupi Signed-off-by: Sagi Grimberg Signed-off-by: Christoph Hellwig Signed-off-by: Sasha Levin --- drivers/nvme/target/tcp.c | 28 ++++++++++++++++++---------- 1 file changed, 18 insertions(+), 10 deletions(-) diff --git a/drivers/nvme/target/tcp.c b/drivers/nvme/target/tcp.c index 577ce7d403ae9..8b0485ada315b 100644 --- a/drivers/nvme/target/tcp.c +++ b/drivers/nvme/target/tcp.c @@ -1485,17 +1485,27 @@ static int nvmet_tcp_set_queue_sock(struct nvmet_tcp_queue *queue) if (inet->rcv_tos > 0) ip_sock_set_tos(sock->sk, inet->rcv_tos); + ret = 0; write_lock_bh(&sock->sk->sk_callback_lock); - sock->sk->sk_user_data = queue; - queue->data_ready = sock->sk->sk_data_ready; - sock->sk->sk_data_ready = nvmet_tcp_data_ready; - queue->state_change = sock->sk->sk_state_change; - sock->sk->sk_state_change = nvmet_tcp_state_change; - queue->write_space = sock->sk->sk_write_space; - sock->sk->sk_write_space = nvmet_tcp_write_space; + if (sock->sk->sk_state != TCP_ESTABLISHED) { + /* + * If the socket is already closing, don't even start + * consuming it + */ + ret = -ENOTCONN; + } else { + sock->sk->sk_user_data = queue; + queue->data_ready = sock->sk->sk_data_ready; + sock->sk->sk_data_ready = nvmet_tcp_data_ready; + queue->state_change = sock->sk->sk_state_change; + sock->sk->sk_state_change = nvmet_tcp_state_change; + queue->write_space = sock->sk->sk_write_space; + sock->sk->sk_write_space = nvmet_tcp_write_space; + queue_work_on(queue_cpu(queue), nvmet_tcp_wq, &queue->io_work); + } write_unlock_bh(&sock->sk->sk_callback_lock); - return 0; + return ret; } static int nvmet_tcp_alloc_queue(struct nvmet_tcp_port *port, @@ -1543,8 +1553,6 @@ static int nvmet_tcp_alloc_queue(struct nvmet_tcp_port *port, if (ret) goto out_destroy_sq; - queue_work_on(queue_cpu(queue), nvmet_tcp_wq, &queue->io_work); - return 0; out_destroy_sq: mutex_lock(&nvmet_tcp_queue_mutex); -- 2.27.0