The following commit has been merged in the master branch: commit 60154a1e0495ffb8343a95cefe1e874634572fa8 Author: Sven Eckelmann sven@narfation.org Date: Sat Jul 2 09:52:14 2016 +0200

batman-adv: Avoid nullptr dereference in dat after vlan_insert_tag

vlan_insert_tag can return NULL on errors. The distributed arp table code therefore has to check the return value of vlan_insert_tag for NULL before it can safely operate on this pointer.

Fixes: be1db4f6615b ("batman-adv: make the Distributed ARP Table vlan aware") Signed-off-by: Sven Eckelmann sven@narfation.org Signed-off-by: Marek Lindner mareklindner@neomailbox.ch Signed-off-by: Simon Wunderlich sw@simonwunderlich.de

diff --git a/net/batman-adv/distributed-arp-table.c b/net/batman-adv/distributed-arp-table.c index 278800a..aee3b39 100644 --- a/net/batman-adv/distributed-arp-table.c +++ b/net/batman-adv/distributed-arp-table.c @@ -1009,9 +1009,12 @@ bool batadv_dat_snoop_outgoing_arp_request(struct batadv_priv *bat_priv, if (!skb_new) goto out;

- if (vid & BATADV_VLAN_HAS_TAG) + if (vid & BATADV_VLAN_HAS_TAG) { skb_new = vlan_insert_tag(skb_new, htons(ETH_P_8021Q), vid & VLAN_VID_MASK); + if (!skb_new) + goto out; + }

skb_reset_mac_header(skb_new); skb_new->protocol = eth_type_trans(skb_new, @@ -1089,9 +1092,12 @@ bool batadv_dat_snoop_incoming_arp_request(struct batadv_priv *bat_priv, */ skb_reset_mac_header(skb_new);

- if (vid & BATADV_VLAN_HAS_TAG) + if (vid & BATADV_VLAN_HAS_TAG) { skb_new = vlan_insert_tag(skb_new, htons(ETH_P_8021Q), vid & VLAN_VID_MASK); + if (!skb_new) + goto out; + }

/* To preserve backwards compatibility, the node has choose the outgoing * format based on the incoming request packet type. The assumption is