From patchwork Sat Mar 5 12:28:42 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Sven Eckelmann X-Patchwork-Id: 857 Return-Path: Received: from v3-1039.vlinux.de (narfation.org [79.140.41.39]) by open-mesh.org (Postfix) with ESMTPS id 4E104154316 for ; Sat, 5 Mar 2011 13:30:31 +0100 (CET) Authentication-Results: open-mesh.org; dkim=pass (1024-bit key) header.i=@narfation.org; dkim-adsp=pass Received: from sven-desktop.home.narfation.org (i59F6B254.versanet.de [89.246.178.84]) by v3-1039.vlinux.de (Postfix) with ESMTPSA id CE165940C8; Sat, 5 Mar 2011 13:30:32 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=narfation.org; s=mail; t=1299328233; bh=bRc6H2SnEhNqzi0xbZtSz0luZ2IfZ9WEyoQUkq0PTUI=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version:Content-Type:Content-Transfer-Encoding; b=Jvfwl0rfrsIEzp4Ei+Lzqe5maqbvCXKfE/ns9DysivvwyALPWnnOnduO2f2FEwjK2 hugoy4lh449brkSxGmgnKAof9LpPtjHrTb6vr9UarhyOov+TgaEdmPp8c1+COeHz3C EIxcZE05NkV86HVoLKZeP4fp3cBtwZYqLxPUNcMY= From: Sven Eckelmann To: davem@davemloft.net Date: Sat, 5 Mar 2011 13:28:42 +0100 Message-Id: <1299328122-21468-29-git-send-email-sven@narfation.org> X-Mailer: git-send-email 1.7.2.3 In-Reply-To: <1299328122-21468-1-git-send-email-sven@narfation.org> References: <1299328122-21468-1-git-send-email-sven@narfation.org> MIME-Version: 1.0 Cc: netdev@vger.kernel.org, b.a.t.m.a.n@lists.open-mesh.org, Marek Lindner Subject: [B.A.T.M.A.N.] [PATCH 28/28] batman-adv: Disallow regular interface as mesh device X-BeenThere: b.a.t.m.a.n@lists.open-mesh.org X-Mailman-Version: 2.1.13 Precedence: list Reply-To: The list for a Better Approach To Mobile Ad-hoc Networking List-Id: The list for a Better Approach To Mobile Ad-hoc Networking List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 05 Mar 2011 12:30:31 -0000 When trying to associate a net_device with another net_device which already exists, batman-adv assumes that this interface is a fully initialized batman mesh interface without checking it. The behaviour when accessing data behind netdev_priv of a random net_device is undefined and potentially dangerous. Reported-by: Linus Lüssing Signed-off-by: Marek Lindner --- net/batman-adv/hard-interface.c | 34 ++++++++++++++++++++++------------ net/batman-adv/soft-interface.c | 13 +++++++++++++ net/batman-adv/soft-interface.h | 1 + 3 files changed, 36 insertions(+), 12 deletions(-) diff --git a/net/batman-adv/hard-interface.c b/net/batman-adv/hard-interface.c index 95a35b6..b3058e4 100644 --- a/net/batman-adv/hard-interface.c +++ b/net/batman-adv/hard-interface.c @@ -79,13 +79,8 @@ static int is_valid_iface(struct net_device *net_dev) return 0; /* no batman over batman */ -#ifdef HAVE_NET_DEVICE_OPS - if (net_dev->netdev_ops->ndo_start_xmit == interface_tx) + if (softif_is_valid(net_dev)) return 0; -#else - if (net_dev->hard_start_xmit == interface_tx) - return 0; -#endif /* Device is being bridged */ /* if (net_dev->priv_flags & IFF_BRIDGE_PORT) @@ -282,6 +277,8 @@ int hardif_enable_interface(struct hard_iface *hard_iface, char *iface_name) { struct bat_priv *bat_priv; struct batman_packet *batman_packet; + struct net_device *soft_iface; + int ret; if (hard_iface->if_status != IF_NOT_IN_USE) goto out; @@ -289,18 +286,30 @@ int hardif_enable_interface(struct hard_iface *hard_iface, char *iface_name) if (!atomic_inc_not_zero(&hard_iface->refcount)) goto out; - hard_iface->soft_iface = dev_get_by_name(&init_net, iface_name); + soft_iface = dev_get_by_name(&init_net, iface_name); - if (!hard_iface->soft_iface) { - hard_iface->soft_iface = softif_create(iface_name); + if (!soft_iface) { + soft_iface = softif_create(iface_name); - if (!hard_iface->soft_iface) + if (!soft_iface) { + ret = -ENOMEM; goto err; + } /* dev_get_by_name() increases the reference counter for us */ - dev_hold(hard_iface->soft_iface); + dev_hold(soft_iface); + } + + if (!softif_is_valid(soft_iface)) { + pr_err("Can't create batman mesh interface %s: " + "already exists as regular interface\n", + soft_iface->name); + dev_put(soft_iface); + ret = -EINVAL; + goto err; } + hard_iface->soft_iface = soft_iface; bat_priv = netdev_priv(hard_iface->soft_iface); hard_iface->packet_len = BAT_PACKET_LEN; hard_iface->packet_buff = kmalloc(hard_iface->packet_len, GFP_ATOMIC); @@ -308,6 +317,7 @@ int hardif_enable_interface(struct hard_iface *hard_iface, char *iface_name) if (!hard_iface->packet_buff) { bat_err(hard_iface->soft_iface, "Can't add interface packet " "(%s): out of memory\n", hard_iface->net_dev->name); + ret = -ENOMEM; goto err; } @@ -370,7 +380,7 @@ out: err: hardif_free_ref(hard_iface); - return -ENOMEM; + return ret; } void hardif_disable_interface(struct hard_iface *hard_iface) diff --git a/net/batman-adv/soft-interface.c b/net/batman-adv/soft-interface.c index 6b514ec..9ed2614 100644 --- a/net/batman-adv/soft-interface.c +++ b/net/batman-adv/soft-interface.c @@ -622,6 +622,19 @@ void softif_destroy(struct net_device *soft_iface) unregister_netdevice(soft_iface); } +int softif_is_valid(struct net_device *net_dev) +{ +#ifdef HAVE_NET_DEVICE_OPS + if (net_dev->netdev_ops->ndo_start_xmit == interface_tx) + return 1; +#else + if (net_dev->hard_start_xmit == interface_tx) + return 1; +#endif + + return 0; +} + /* ethtool */ static int bat_get_settings(struct net_device *dev, struct ethtool_cmd *cmd) { diff --git a/net/batman-adv/soft-interface.h b/net/batman-adv/soft-interface.h index 80a3607..4789b6f 100644 --- a/net/batman-adv/soft-interface.h +++ b/net/batman-adv/soft-interface.h @@ -31,5 +31,6 @@ void interface_rx(struct net_device *soft_iface, int hdr_size); struct net_device *softif_create(char *name); void softif_destroy(struct net_device *soft_iface); +int softif_is_valid(struct net_device *net_dev); #endif /* _NET_BATMAN_ADV_SOFT_INTERFACE_H_ */