From patchwork Tue Jul 17 15:19:43 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Simon Wunderlich X-Patchwork-Id: 17424 X-Patchwork-Delegate: sw@simonwunderlich.de Return-Path: X-Original-To: patchwork@open-mesh.org Delivered-To: patchwork@open-mesh.org Received: from open-mesh.org (localhost [IPv6:::1]) by open-mesh.org (Postfix) with ESMTP id CC9E482733; Tue, 17 Jul 2018 17:26:07 +0200 (CEST) Received-SPF: Pass (mailfrom) identity=mailfrom; client-ip=2001:4d88:2000:24::c0de; helo=mail.mail.packetmixer.de; envelope-from=sw@simonwunderlich.de; receiver= X-Greylist: delayed 359 seconds by postgrey-1.36 at open-mesh.org; Tue, 17 Jul 2018 17:25:51 CEST Received: from mail.mail.packetmixer.de (packetmixer.de [IPv6:2001:4d88:2000:24::c0de]) by open-mesh.org (Postfix) with ESMTPS id F0C3581935 for ; Tue, 17 Jul 2018 17:25:51 +0200 (CEST) Received: from kero.packetmixer.de (p200300C593D61D0054FF2B5AC1794F2F.dip0.t-ipconnect.de [IPv6:2003:c5:93d6:1d00:54ff:2b5a:c179:4f2f]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.mail.packetmixer.de (Postfix) with ESMTPSA id D73E762057; Tue, 17 Jul 2018 17:19:53 +0200 (CEST) From: Simon Wunderlich To: davem@davemloft.net Date: Tue, 17 Jul 2018 17:19:43 +0200 Message-Id: <20180717151946.31900-4-sw@simonwunderlich.de> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20180717151946.31900-1-sw@simonwunderlich.de> References: <20180717151946.31900-1-sw@simonwunderlich.de> Subject: [B.A.T.M.A.N.] [PATCH 3/6] batman-adv: Fix debugfs path for renamed hardif X-BeenThere: b.a.t.m.a.n@lists.open-mesh.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: The list for a Better Approach To Mobile Ad-hoc Networking List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: The list for a Better Approach To Mobile Ad-hoc Networking Cc: netdev@vger.kernel.org, b.a.t.m.a.n@lists.open-mesh.org Errors-To: b.a.t.m.a.n-bounces@lists.open-mesh.org Sender: "B.A.T.M.A.N" From: Sven Eckelmann batman-adv is creating special debugfs directories in the init net_namespace for each valid hard-interface (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 net_device which gets the name "wlan0" assigned by default. batman-adv is also adding a new directory under $debugfs/batman-adv/ with the name "wlan0". The user then decides to rename this device to "wl_pri" and registers a different device. The kernel may now decide to use the name "wlan0" again for this new device. batman-adv will detect it as a valid net_device and tries to create a directory with the name "wlan0" under $debugfs/batman-adv/. 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 hard-interfaces whenever it detects such a net_device rename. Fixes: 5bc7c1eb44f2 ("batman-adv: add debugfs structure for information per interface") Reported-by: John Soros Signed-off-by: Sven Eckelmann Signed-off-by: Simon Wunderlich --- net/batman-adv/debugfs.c | 20 ++++++++++++++++++++ net/batman-adv/debugfs.h | 6 ++++++ net/batman-adv/hard-interface.c | 3 +++ 3 files changed, 29 insertions(+) diff --git a/net/batman-adv/debugfs.c b/net/batman-adv/debugfs.c index 4229b01ac7b5..7e5de7b9f6d5 100644 --- a/net/batman-adv/debugfs.c +++ b/net/batman-adv/debugfs.c @@ -19,6 +19,7 @@ #include "debugfs.h" #include "main.h" +#include #include #include #include @@ -344,6 +345,25 @@ int batadv_debugfs_add_hardif(struct batadv_hard_iface *hard_iface) } /** + * batadv_debugfs_rename_hardif() - Fix debugfs path for renamed hardif + * @hard_iface: hard interface which was renamed + */ +void batadv_debugfs_rename_hardif(struct batadv_hard_iface *hard_iface) +{ + const char *name = hard_iface->net_dev->name; + struct dentry *dir; + struct dentry *d; + + dir = hard_iface->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_hardif() - delete the base directory for a hard interface * in debugfs. * @hard_iface: hard interface which is deleted. diff --git a/net/batman-adv/debugfs.h b/net/batman-adv/debugfs.h index 37b069698b04..8538a7a75e93 100644 --- a/net/batman-adv/debugfs.h +++ b/net/batman-adv/debugfs.h @@ -32,6 +32,7 @@ void batadv_debugfs_destroy(void); int batadv_debugfs_add_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); void batadv_debugfs_del_hardif(struct batadv_hard_iface *hard_iface); #else @@ -60,6 +61,11 @@ int batadv_debugfs_add_hardif(struct batadv_hard_iface *hard_iface) } static inline +void batadv_debugfs_rename_hardif(struct batadv_hard_iface *hard_iface) +{ +} + +static inline void batadv_debugfs_del_hardif(struct batadv_hard_iface *hard_iface) { } diff --git a/net/batman-adv/hard-interface.c b/net/batman-adv/hard-interface.c index c405d15befd6..dc2763b11107 100644 --- a/net/batman-adv/hard-interface.c +++ b/net/batman-adv/hard-interface.c @@ -1051,6 +1051,9 @@ static int batadv_hard_if_event(struct notifier_block *this, if (batadv_is_wifi_hardif(hard_iface)) hard_iface->num_bcasts = BATADV_NUM_BCASTS_WIRELESS; break; + case NETDEV_CHANGENAME: + batadv_debugfs_rename_hardif(hard_iface); + break; default: break; }