From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:42886 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754676AbbJRCbX (ORCPT ); Sat, 17 Oct 2015 22:31:23 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Ryan Thompson , Marek Lindner , Antonio Quartulli Subject: [PATCH 4.1 125/202] batman-adv: fix kernel crash due to missing NULL checks Date: Sat, 17 Oct 2015 18:58:28 -0700 Message-Id: <20151018014907.595468281@linuxfoundation.org> In-Reply-To: <20151018014901.946875729@linuxfoundation.org> References: <20151018014901.946875729@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Sender: stable-owner@vger.kernel.org List-ID: 4.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Marek Lindner commit 354136bcc3c4f40a2813bba8f57ca5267d812d15 upstream. 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 Signed-off-by: Greg Kroah-Hartman --- net/batman-adv/soft-interface.c | 3 +++ net/batman-adv/translation-table.c | 18 ++++++++++++++---- 2 files changed, 17 insertions(+), 4 deletions(-) --- a/net/batman-adv/soft-interface.c +++ b/net/batman-adv/soft-interface.c @@ -449,6 +449,9 @@ 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); --- a/net/batman-adv/translation-table.c +++ b/net/batman-adv/translation-table.c @@ -575,6 +575,9 @@ bool batadv_tt_local_add(struct net_devi /* 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", @@ -1047,6 +1050,9 @@ uint16_t batadv_tt_local_remove(struct b /* 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); @@ -1147,8 +1153,10 @@ static void batadv_tt_local_table_free(s /* 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); } @@ -3188,8 +3196,10 @@ static void batadv_tt_local_purge_pendin /* 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); }