blob: 5ad42ff42a0104b0cbd0f3a23de67202ad56b409 [file] [log] [blame]
From: Sven Eckelmann <sven@narfation.org>
Date: Sat, 2 Jul 2016 09:52:14 +0200
Subject: batman-adv: Avoid nullptr dereference in dat after vlan_insert_tag
commit 60154a1e0495ffb8343a95cefe1e874634572fa8 upstream.
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>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
net/batman-adv/distributed-arp-table.c | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)
--- a/net/batman-adv/distributed-arp-table.c
+++ b/net/batman-adv/distributed-arp-table.c
@@ -959,9 +959,12 @@ bool batadv_dat_snoop_outgoing_arp_reque
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,
@@ -1039,9 +1042,12 @@ bool batadv_dat_snoop_incoming_arp_reque
*/
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