From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932833AbaE2EgH (ORCPT ); Thu, 29 May 2014 00:36:07 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:58194 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932775AbaE2Ef7 (ORCPT ); Thu, 29 May 2014 00:35:59 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Antonio Quartulli , Marek Lindner Subject: [PATCH 3.14 134/140] batman-adv: increase orig refcount when storing ref in gw_node Date: Wed, 28 May 2014 21:34:33 -0700 Message-Id: <20140529043106.591017117@linuxfoundation.org> X-Mailer: git-send-email 2.0.0.rc3.2.g998f840 In-Reply-To: <20140529043049.661315084@linuxfoundation.org> References: <20140529043049.661315084@linuxfoundation.org> User-Agent: quilt/0.60-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Antonio Quartulli [ Upstream commit 377fe0f968b30a1a714fab53a908061914f30e26 ] A pointer to the orig_node representing a bat-gateway is stored in the gw_node->orig_node member, but the refcount for such orig_node is never increased. This leads to memory faults when gw_node->orig_node is accessed and the originator has already been freed. Fix this by increasing the refcount on gw_node creation and decreasing it on gw_node free. Signed-off-by: Antonio Quartulli Signed-off-by: Marek Lindner Signed-off-by: Greg Kroah-Hartman --- net/batman-adv/gateway_client.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) --- a/net/batman-adv/gateway_client.c +++ b/net/batman-adv/gateway_client.c @@ -42,8 +42,10 @@ static void batadv_gw_node_free_ref(struct batadv_gw_node *gw_node) { - if (atomic_dec_and_test(&gw_node->refcount)) + if (atomic_dec_and_test(&gw_node->refcount)) { + batadv_orig_node_free_ref(gw_node->orig_node); kfree_rcu(gw_node, rcu); + } } static struct batadv_gw_node * @@ -408,9 +410,14 @@ static void batadv_gw_node_add(struct ba if (gateway->bandwidth_down == 0) return; + if (!atomic_inc_not_zero(&orig_node->refcount)) + return; + gw_node = kzalloc(sizeof(*gw_node), GFP_ATOMIC); - if (!gw_node) + if (!gw_node) { + batadv_orig_node_free_ref(orig_node); return; + } INIT_HLIST_NODE(&gw_node->list); gw_node->orig_node = orig_node;