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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,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 027DAC432C3 for ; Tue, 19 Nov 2019 06:12:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C8B7420692 for ; Tue, 19 Nov 2019 06:12:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1574143955; bh=Jx7N3naRKuizoBu6BtVpPJsrEwHfHDwHNVNCUvzTgPk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=mzK6I/Ph1+oTwfx6gTuk/fmJSGn0/wcMulh8Ny1vE6EOdiaT/rs321jPWi/c8lEkE VpvMDyfNfgI+Us65QBZgvSvQcLL4vUUoxTZIFIC3OC85wuYATgxqv2KXYjrAqr9dB1 9uLljwi31VZTyZQ2I0V6X3HubaC/IGQjt9LX56OU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727591AbfKSFV7 (ORCPT ); Tue, 19 Nov 2019 00:21:59 -0500 Received: from mail.kernel.org ([198.145.29.99]:37116 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727539AbfKSFV6 (ORCPT ); Tue, 19 Nov 2019 00:21:58 -0500 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 6CF2022317; Tue, 19 Nov 2019 05:21:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1574140916; bh=Jx7N3naRKuizoBu6BtVpPJsrEwHfHDwHNVNCUvzTgPk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=WqN1/A2GzX74/6RQCRxmQyW2iDKgSe9FfNyXPeWhl4sBlG3eJuZlICpWyTNrEFKqh Yde5In4m7OPh0SpXOpYPF0UMfrbYlGr4+wl6H8wXy2XI/jPLa7rWxHzcKoE9tM0Bl0 Ic50pB2X3OeCIJnTElIOg/Uercyrjjj/d+pTN/Jw= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Ido Schimmel , Jiri Pirko , "David S. Miller" Subject: [PATCH 5.3 03/48] devlink: disallow reload operation during device cleanup Date: Tue, 19 Nov 2019 06:19:23 +0100 Message-Id: <20191119050949.815080213@linuxfoundation.org> X-Mailer: git-send-email 2.24.0 In-Reply-To: <20191119050946.745015350@linuxfoundation.org> References: <20191119050946.745015350@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 From: Jiri Pirko [ Upstream commit 5a508a254bed9a2e36a5fb96c9065532a6bf1e9c ] There is a race between driver code that does setup/cleanup of device and devlink reload operation that in some drivers works with the same code. Use after free could we easily obtained by running: while true; do echo "0000:00:10.0" >/sys/bus/pci/drivers/mlxsw_spectrum2/bind devlink dev reload pci/0000:00:10.0 & echo "0000:00:10.0" >/sys/bus/pci/drivers/mlxsw_spectrum2/unbind done Fix this by enabling reload only after setup of device is complete and disabling it at the beginning of the cleanup process. Reported-by: Ido Schimmel Fixes: 2d8dc5bbf4e7 ("devlink: Add support for reload") Signed-off-by: Jiri Pirko Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- drivers/net/ethernet/mellanox/mlx4/main.c | 3 ++ drivers/net/ethernet/mellanox/mlxsw/core.c | 6 +++- drivers/net/netdevsim/dev.c | 2 + include/net/devlink.h | 3 ++ net/core/devlink.c | 39 ++++++++++++++++++++++++++++- 5 files changed, 51 insertions(+), 2 deletions(-) --- a/drivers/net/ethernet/mellanox/mlx4/main.c +++ b/drivers/net/ethernet/mellanox/mlx4/main.c @@ -3982,6 +3982,7 @@ static int mlx4_init_one(struct pci_dev goto err_params_unregister; devlink_params_publish(devlink); + devlink_reload_enable(devlink); pci_save_state(pdev); return 0; @@ -4093,6 +4094,8 @@ static void mlx4_remove_one(struct pci_d struct devlink *devlink = priv_to_devlink(priv); int active_vfs = 0; + devlink_reload_disable(devlink); + if (mlx4_is_slave(dev)) persist->interface_state |= MLX4_INTERFACE_STATE_NOWAIT; --- a/drivers/net/ethernet/mellanox/mlxsw/core.c +++ b/drivers/net/ethernet/mellanox/mlxsw/core.c @@ -1128,8 +1128,10 @@ __mlxsw_core_bus_device_register(const s if (err) goto err_thermal_init; - if (mlxsw_driver->params_register) + if (mlxsw_driver->params_register) { devlink_params_publish(devlink); + devlink_reload_enable(devlink); + } return 0; @@ -1191,6 +1193,8 @@ void mlxsw_core_bus_device_unregister(st { struct devlink *devlink = priv_to_devlink(mlxsw_core); + if (!reload) + devlink_reload_disable(devlink); if (mlxsw_core->reload_fail) { if (!reload) /* Only the parts that were not de-initialized in the --- a/drivers/net/netdevsim/dev.c +++ b/drivers/net/netdevsim/dev.c @@ -297,6 +297,7 @@ nsim_dev_create(struct nsim_bus_dev *nsi if (err) goto err_debugfs_exit; + devlink_reload_enable(devlink); return nsim_dev; err_debugfs_exit: @@ -314,6 +315,7 @@ static void nsim_dev_destroy(struct nsim { struct devlink *devlink = priv_to_devlink(nsim_dev); + devlink_reload_disable(devlink); nsim_bpf_dev_exit(nsim_dev); nsim_dev_debugfs_exit(nsim_dev); devlink_unregister(devlink); --- a/include/net/devlink.h +++ b/include/net/devlink.h @@ -35,6 +35,7 @@ struct devlink { struct device *dev; possible_net_t _net; struct mutex lock; + u8 reload_enabled:1; char priv[0] __aligned(NETDEV_ALIGN); }; @@ -594,6 +595,8 @@ struct ib_device; struct devlink *devlink_alloc(const struct devlink_ops *ops, size_t priv_size); int devlink_register(struct devlink *devlink, struct device *dev); void devlink_unregister(struct devlink *devlink); +void devlink_reload_enable(struct devlink *devlink); +void devlink_reload_disable(struct devlink *devlink); void devlink_free(struct devlink *devlink); int devlink_port_register(struct devlink *devlink, struct devlink_port *devlink_port, --- a/net/core/devlink.c +++ b/net/core/devlink.c @@ -2677,7 +2677,7 @@ static int devlink_nl_cmd_reload(struct struct devlink *devlink = info->user_ptr[0]; int err; - if (!devlink->ops->reload) + if (!devlink->ops->reload || !devlink->reload_enabled) return -EOPNOTSUPP; err = devlink_resources_validate(devlink, NULL, info); @@ -5559,6 +5559,8 @@ EXPORT_SYMBOL_GPL(devlink_register); void devlink_unregister(struct devlink *devlink) { mutex_lock(&devlink_mutex); + WARN_ON(devlink_reload_supported(devlink) && + devlink->reload_enabled); devlink_notify(devlink, DEVLINK_CMD_DEL); list_del(&devlink->list); mutex_unlock(&devlink_mutex); @@ -5566,6 +5568,41 @@ void devlink_unregister(struct devlink * EXPORT_SYMBOL_GPL(devlink_unregister); /** + * devlink_reload_enable - Enable reload of devlink instance + * + * @devlink: devlink + * + * Should be called at end of device initialization + * process when reload operation is supported. + */ +void devlink_reload_enable(struct devlink *devlink) +{ + mutex_lock(&devlink_mutex); + devlink->reload_enabled = true; + mutex_unlock(&devlink_mutex); +} +EXPORT_SYMBOL_GPL(devlink_reload_enable); + +/** + * devlink_reload_disable - Disable reload of devlink instance + * + * @devlink: devlink + * + * Should be called at the beginning of device cleanup + * process when reload operation is supported. + */ +void devlink_reload_disable(struct devlink *devlink) +{ + mutex_lock(&devlink_mutex); + /* Mutex is taken which ensures that no reload operation is in + * progress while setting up forbidded flag. + */ + devlink->reload_enabled = false; + mutex_unlock(&devlink_mutex); +} +EXPORT_SYMBOL_GPL(devlink_reload_disable); + +/** * devlink_free - Free devlink instance resources * * @devlink: devlink