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=-4.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED 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 570E8C43441 for ; Sun, 11 Nov 2018 20:07:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 257D72080D for ; Sun, 11 Nov 2018 20:07:59 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 257D72080D Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=decadent.org.uk Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731601AbeKLF5Z (ORCPT ); Mon, 12 Nov 2018 00:57:25 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:52220 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730938AbeKLF5Z (ORCPT ); Mon, 12 Nov 2018 00:57:25 -0500 Received: from [192.168.4.242] (helo=deadeye) by shadbolt.decadent.org.uk with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1gLvsy-0000lG-5t; Sun, 11 Nov 2018 19:59:08 +0000 Received: from ben by deadeye with local (Exim 4.91) (envelope-from ) id 1gLvsT-0001cl-Tp; Sun, 11 Nov 2018 19:58:37 +0000 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Sven Eckelmann" , "Simon Wunderlich" Date: Sun, 11 Nov 2018 19:49:05 +0000 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 188/366] batman-adv: Fix debugfs path for renamed softif In-Reply-To: X-SA-Exim-Connect-IP: 192.168.4.242 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.61-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Sven Eckelmann commit 6da7be7d24b2921f8215473ba7552796dff05fe1 upstream. batman-adv is creating special debugfs directories in the init net_namespace for each created soft-interface (batadv net_device). But it is possible to rename a net_device to a completely different name then the original one. It can therefore happen that a user registers a new batadv net_device with the name "bat0". batman-adv is then also adding a new directory under $debugfs/batman-adv/ with the name "wlan0". The user then decides to rename this device to "bat1" and registers a different batadv device with the name "bat0". batman-adv will then try to create a directory with the name "bat0" under $debugfs/batman-adv/ again. But there already exists one with this name under this path and thus this fails. batman-adv will detect a problem and rollback the registering of this device. batman-adv must therefore take care of renaming the debugfs directories for soft-interfaces whenever it detects such a net_device rename. Fixes: c6c8fea29769 ("net: Add batman-adv meshing protocol") Signed-off-by: Sven Eckelmann Signed-off-by: Simon Wunderlich [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings --- net/batman-adv/debugfs.c | 20 +++++++++++++++++++ net/batman-adv/debugfs.h | 5 +++++ net/batman-adv/hard-interface.c | 34 +++++++++++++++++++++++++++------ 3 files changed, 53 insertions(+), 6 deletions(-) --- a/net/batman-adv/debugfs.c +++ b/net/batman-adv/debugfs.c @@ -560,6 +560,26 @@ out: return -ENOMEM; } +/** + * batadv_debugfs_rename_meshif() - Fix debugfs path for renamed softif + * @dev: net_device which was renamed + */ +void batadv_debugfs_rename_meshif(struct net_device *dev) +{ + struct batadv_priv *bat_priv = netdev_priv(dev); + const char *name = dev->name; + struct dentry *dir; + struct dentry *d; + + dir = bat_priv->debug_dir; + if (!dir) + return; + + d = debugfs_rename(dir->d_parent, dir, dir->d_parent, name); + if (!d) + pr_err("Can't rename debugfs dir to %s\n", name); +} + void batadv_debugfs_del_meshif(struct net_device *dev) { struct batadv_priv *bat_priv = netdev_priv(dev); --- a/net/batman-adv/debugfs.h +++ b/net/batman-adv/debugfs.h @@ -25,6 +25,7 @@ void batadv_debugfs_init(void); void batadv_debugfs_destroy(void); int batadv_debugfs_add_meshif(struct net_device *dev); +void batadv_debugfs_rename_meshif(struct net_device *dev); void batadv_debugfs_del_meshif(struct net_device *dev); int batadv_debugfs_add_hardif(struct batadv_hard_iface *hard_iface); void batadv_debugfs_rename_hardif(struct batadv_hard_iface *hard_iface); @@ -45,6 +46,10 @@ static inline int batadv_debugfs_add_mes return 0; } +static inline void batadv_debugfs_rename_meshif(struct net_device *dev) +{ +} + static inline void batadv_debugfs_del_meshif(struct net_device *dev) { } --- a/net/batman-adv/hard-interface.c +++ b/net/batman-adv/hard-interface.c @@ -640,6 +640,32 @@ void batadv_hardif_remove_interfaces(voi rtnl_unlock(); } +/** + * batadv_hard_if_event_softif() - Handle events for soft interfaces + * @event: NETDEV_* event to handle + * @net_dev: net_device which generated an event + * + * Return: NOTIFY_* result + */ +static int batadv_hard_if_event_softif(unsigned long event, + struct net_device *net_dev) +{ + struct batadv_priv *bat_priv; + + switch (event) { + case NETDEV_REGISTER: + batadv_sysfs_add_meshif(net_dev); + bat_priv = netdev_priv(net_dev); + batadv_softif_create_vlan(bat_priv, BATADV_NO_FLAGS); + break; + case NETDEV_CHANGENAME: + batadv_debugfs_rename_meshif(net_dev); + break; + } + + return NOTIFY_DONE; +} + static int batadv_hard_if_event(struct notifier_block *this, unsigned long event, void *ptr) { @@ -648,12 +674,8 @@ static int batadv_hard_if_event(struct n struct batadv_hard_iface *primary_if = NULL; struct batadv_priv *bat_priv; - if (batadv_softif_is_valid(net_dev) && event == NETDEV_REGISTER) { - batadv_sysfs_add_meshif(net_dev); - bat_priv = netdev_priv(net_dev); - batadv_softif_create_vlan(bat_priv, BATADV_NO_FLAGS); - return NOTIFY_DONE; - } + if (batadv_softif_is_valid(net_dev)) + return batadv_hard_if_event_softif(event, net_dev); hard_iface = batadv_hardif_get_by_netdev(net_dev); if (!hard_iface && event == NETDEV_REGISTER)