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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 ED54FC3A5A8 for ; Wed, 4 Sep 2019 18:21:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C84372087E for ; Wed, 4 Sep 2019 18:21:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1567621284; bh=3dQiJ0I3nOjQlJ5QXGYzOKeUQs0f52s6ysCBJrBzAZk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=Nb0eUAzk345LlCMEYzOA+zBO2IgmLfSsk87FEq8895sODMlEA4vSubtwt5+liP21d avKluJ/avvFat4yc6lFQMHx9Ha6ke2KhpxyOqyyGwKZ8qO+QP4+QnJ+zt+eE+GWI9h RdIArkwh9IRe9laFaJ0O1J4ApTb5wb0StYRVk2rI= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388768AbfIDSGp (ORCPT ); Wed, 4 Sep 2019 14:06:45 -0400 Received: from mail.kernel.org ([198.145.29.99]:48854 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732321AbfIDSGo (ORCPT ); Wed, 4 Sep 2019 14:06:44 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 0C61C208E4; Wed, 4 Sep 2019 18:06:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1567620403; bh=3dQiJ0I3nOjQlJ5QXGYzOKeUQs0f52s6ysCBJrBzAZk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=HjoAC5mhX40fikAT20evM3zwu4Ni8sxlcP9c4DIlzb7bCwLykNCmEi2SNhAkmhqaZ kWaqt8lNCYD+OHb6IL9APLKtLlTtCjZgP51awR15Py27G4IWn2XI1UmAsjymUTsGvK 5++Zl4/upRxOS5bOLVbvczJnnvoZoixl6hsNIoHs= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Logan Gunthorpe , Sagi Grimberg , Max Gurtovoy , Sasha Levin Subject: [PATCH 4.19 07/93] nvmet-loop: Flush nvme_delete_wq when removing the port Date: Wed, 4 Sep 2019 19:53:09 +0200 Message-Id: <20190904175303.699597924@linuxfoundation.org> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20190904175302.845828956@linuxfoundation.org> References: <20190904175302.845828956@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org [ Upstream commit 86b9a63e595ff03f9d0a7b92b6acc231fecefc29 ] After calling nvme_loop_delete_ctrl(), the controllers will not yet be deleted because nvme_delete_ctrl() only schedules work to do the delete. This means a race can occur if a port is removed but there are still active controllers trying to access that memory. To fix this, flush the nvme_delete_wq before returning from nvme_loop_remove_port() so that any controllers that might be in the process of being deleted won't access a freed port. Signed-off-by: Logan Gunthorpe Reviewed-by: Sagi Grimberg Reviewed-by: Max Gurtovoy Reviewed-by : Chaitanya Kulkarni Signed-off-by: Sagi Grimberg Signed-off-by: Sasha Levin --- drivers/nvme/target/loop.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/drivers/nvme/target/loop.c b/drivers/nvme/target/loop.c index 9908082b32c4b..137a27fa369cb 100644 --- a/drivers/nvme/target/loop.c +++ b/drivers/nvme/target/loop.c @@ -678,6 +678,14 @@ static void nvme_loop_remove_port(struct nvmet_port *port) mutex_lock(&nvme_loop_ports_mutex); list_del_init(&port->entry); mutex_unlock(&nvme_loop_ports_mutex); + + /* + * Ensure any ctrls that are in the process of being + * deleted are in fact deleted before we return + * and free the port. This is to prevent active + * ctrls from using a port after it's freed. + */ + flush_workqueue(nvme_delete_wq); } static const struct nvmet_fabrics_ops nvme_loop_ops = { -- 2.20.1