From patchwork Wed Aug 5 12:51:45 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Antonio Quartulli X-Patchwork-Id: 503988 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 0D8D41402C8 for ; Wed, 5 Aug 2015 22:53:43 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752403AbbHEMxU (ORCPT ); Wed, 5 Aug 2015 08:53:20 -0400 Received: from s1.neomailbox.net ([5.148.176.57]:7751 "EHLO s1.neomailbox.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752122AbbHEMxJ (ORCPT ); Wed, 5 Aug 2015 08:53:09 -0400 From: Antonio Quartulli To: davem@davemloft.net Cc: netdev@vger.kernel.org, b.a.t.m.a.n@lists.open-mesh.org, Marek Lindner , Antonio Quartulli Subject: [PATCH 2/4] batman-adv: fix kernel crash due to missing NULL checks Date: Wed, 5 Aug 2015 14:51:45 +0200 Message-Id: <1438779107-12665-3-git-send-email-antonio@meshcoding.com> In-Reply-To: <1438779107-12665-1-git-send-email-antonio@meshcoding.com> References: <1438779107-12665-1-git-send-email-antonio@meshcoding.com> Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Marek Lindner batadv_softif_vlan_get() may return NULL which has to be verified by the caller. Fixes: 35df3b298fc8 ("batman-adv: fix TT VLAN inconsistency on VLAN re-add") Reported-by: Ryan Thompson Signed-off-by: Marek Lindner Signed-off-by: Antonio Quartulli --- net/batman-adv/soft-interface.c | 3 +++ net/batman-adv/translation-table.c | 18 ++++++++++++++---- 2 files changed, 17 insertions(+), 4 deletions(-) diff --git a/net/batman-adv/soft-interface.c b/net/batman-adv/soft-interface.c index c002961..a2fc843 100644 --- a/net/batman-adv/soft-interface.c +++ b/net/batman-adv/soft-interface.c @@ -479,6 +479,9 @@ out: */ void batadv_softif_vlan_free_ref(struct batadv_softif_vlan *vlan) { + if (!vlan) + return; + if (atomic_dec_and_test(&vlan->refcount)) { spin_lock_bh(&vlan->bat_priv->softif_vlan_list_lock); hlist_del_rcu(&vlan->list); diff --git a/net/batman-adv/translation-table.c b/net/batman-adv/translation-table.c index b482495..38b83c5 100644 --- a/net/batman-adv/translation-table.c +++ b/net/batman-adv/translation-table.c @@ -594,6 +594,9 @@ bool batadv_tt_local_add(struct net_device *soft_iface, const uint8_t *addr, /* increase the refcounter of the related vlan */ vlan = batadv_softif_vlan_get(bat_priv, vid); + if (WARN(!vlan, "adding TT local entry %pM to non-existent VLAN %d", + addr, BATADV_PRINT_VID(vid))) + goto out; batadv_dbg(BATADV_DBG_TT, bat_priv, "Creating new local tt entry: %pM (vid: %d, ttvn: %d)\n", @@ -1066,6 +1069,9 @@ uint16_t batadv_tt_local_remove(struct batadv_priv *bat_priv, /* decrease the reference held for this vlan */ vlan = batadv_softif_vlan_get(bat_priv, vid); + if (!vlan) + goto out; + batadv_softif_vlan_free_ref(vlan); batadv_softif_vlan_free_ref(vlan); @@ -1166,8 +1172,10 @@ static void batadv_tt_local_table_free(struct batadv_priv *bat_priv) /* decrease the reference held for this vlan */ vlan = batadv_softif_vlan_get(bat_priv, tt_common_entry->vid); - batadv_softif_vlan_free_ref(vlan); - batadv_softif_vlan_free_ref(vlan); + if (vlan) { + batadv_softif_vlan_free_ref(vlan); + batadv_softif_vlan_free_ref(vlan); + } batadv_tt_local_entry_free_ref(tt_local); } @@ -3207,8 +3215,10 @@ static void batadv_tt_local_purge_pending_clients(struct batadv_priv *bat_priv) /* decrease the reference held for this vlan */ vlan = batadv_softif_vlan_get(bat_priv, tt_common->vid); - batadv_softif_vlan_free_ref(vlan); - batadv_softif_vlan_free_ref(vlan); + if (vlan) { + batadv_softif_vlan_free_ref(vlan); + batadv_softif_vlan_free_ref(vlan); + } batadv_tt_local_entry_free_ref(tt_local); }