batman-adv: Avoid nullptr dereference in bla after vlan_insert_tag

vlan_insert_tag can return NULL on errors. The bridge loop avoidance code
therefore has to check the return value of vlan_insert_tag for NULL before
it can safely operate on this pointer.

Fixes: 23721387c4 ("batman-adv: add basic bridge loop avoidance code")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
This commit is contained in:
Sven Eckelmann 2016-07-02 09:52:13 +02:00 committed by Simon Wunderlich
parent 5b4d10f5e0
commit 10c78f5854

View File

@ -418,9 +418,12 @@ static void batadv_bla_send_claim(struct batadv_priv *bat_priv, u8 *mac,
break;
}
if (vid & BATADV_VLAN_HAS_TAG)
if (vid & BATADV_VLAN_HAS_TAG) {
skb = vlan_insert_tag(skb, htons(ETH_P_8021Q),
vid & VLAN_VID_MASK);
if (!skb)
goto out;
}
skb_reset_mac_header(skb);
skb->protocol = eth_type_trans(skb, soft_iface);