From patchwork Mon Mar 16 22:30:28 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sven Eckelmann X-Patchwork-Id: 229387 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=-9.9 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY,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 5E61BC2BB1D for ; Mon, 16 Mar 2020 22:31:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3765520663 for ; Mon, 16 Mar 2020 22:31:01 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=narfation.org header.i=@narfation.org header.b="C/yjj3Dd" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732798AbgCPWbA (ORCPT ); Mon, 16 Mar 2020 18:31:00 -0400 Received: from dvalin.narfation.org ([213.160.73.56]:48916 "EHLO dvalin.narfation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732743AbgCPWbA (ORCPT ); Mon, 16 Mar 2020 18:31:00 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=narfation.org; s=20121; t=1584397859; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=JVfmF46hxwEIPe/jQFn5XIW3ezmx88Pnjf3wnCV1tWE=; b=C/yjj3DdaNWGA/bphYD30ULk6fnotfUG5FoYCIZ/YrD9JlEIHPlsakJDSCxnZQTGP693wG K/RFvU3F/nuSPbtDL1pTlbt7rFsRZncndwDCdyAuAKglax2DidnsT62WRCsl0qn6pKLjz1 yGfCO8IjTrxGuzsjMdiDaRgjncwOx5k= From: Sven Eckelmann To: stable@vger.kernel.org Cc: Sven Eckelmann , Simon Wunderlich Subject: [PATCH 4.14 11/15] batman-adv: Fix debugfs path for renamed softif Date: Mon, 16 Mar 2020 23:30:28 +0100 Message-Id: <20200316223032.6236-12-sven@narfation.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200316223032.6236-1-sven@narfation.org> References: <20200316223032.6236-1-sven@narfation.org> MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org 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 --- net/batman-adv/debugfs.c | 24 +++++++++++++++++++++++ net/batman-adv/debugfs.h | 5 +++++ net/batman-adv/hard-interface.c | 34 +++++++++++++++++++++++++++------ 3 files changed, 57 insertions(+), 6 deletions(-) diff --git a/net/batman-adv/debugfs.c b/net/batman-adv/debugfs.c index 7ee828cd9778..4957d4824437 100644 --- a/net/batman-adv/debugfs.c +++ b/net/batman-adv/debugfs.c @@ -421,6 +421,30 @@ int batadv_debugfs_add_meshif(struct net_device *dev) 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); +} + +/** + * batadv_debugfs_del_meshif() - Remove interface dependent debugfs entries + * @dev: netdev struct of the soft interface + */ void batadv_debugfs_del_meshif(struct net_device *dev) { struct batadv_priv *bat_priv = netdev_priv(dev); diff --git a/net/batman-adv/debugfs.h b/net/batman-adv/debugfs.h index 295e11146818..901bbc357bf4 100644 --- a/net/batman-adv/debugfs.h +++ b/net/batman-adv/debugfs.h @@ -29,6 +29,7 @@ struct net_device; 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); @@ -49,6 +50,10 @@ static inline int batadv_debugfs_add_meshif(struct net_device *dev) return 0; } +static inline void batadv_debugfs_rename_meshif(struct net_device *dev) +{ +} + static inline void batadv_debugfs_del_meshif(struct net_device *dev) { } diff --git a/net/batman-adv/hard-interface.c b/net/batman-adv/hard-interface.c index e72e95208339..c43887fa29a9 100644 --- a/net/batman-adv/hard-interface.c +++ b/net/batman-adv/hard-interface.c @@ -955,6 +955,32 @@ void batadv_hardif_remove_interfaces(void) 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) { @@ -963,12 +989,8 @@ static int batadv_hard_if_event(struct notifier_block *this, 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 ||