batman-adv: update data pointers after skb_cow()

commit bc44b78157f621ff2a2618fe287a827bcb094ac4 upstream.

batadv_check_unicast_ttvn() calls skb_cow(), so pointers into the SKB data
must be (re)set after calling it. The ethhdr variable is dropped
altogether.

Fixes: 78fc6bbe0aca ("batman-adv: add UNICAST_4ADDR packet type")
Signed-off-by: Matthias Schiffer <mschiffer@universe-factory.net>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Matthias Schiffer 2020-03-17 21:15:38 +01:00 committed by Greg Kroah-Hartman
parent baed34edb0
commit 3c6ed319b8

View File

@ -930,7 +930,6 @@ int batadv_recv_unicast_packet(struct sk_buff *skb,
bool is4addr;
unicast_packet = (struct batadv_unicast_packet *)skb->data;
unicast_4addr_packet = (struct batadv_unicast_4addr_packet *)skb->data;
is4addr = unicast_packet->packet_type == BATADV_UNICAST_4ADDR;
/* the caller function should have already pulled 2 bytes */
@ -951,9 +950,13 @@ int batadv_recv_unicast_packet(struct sk_buff *skb,
if (!batadv_check_unicast_ttvn(bat_priv, skb, hdr_size))
return NET_RX_DROP;
unicast_packet = (struct batadv_unicast_packet *)skb->data;
/* packet for me */
if (batadv_is_my_mac(bat_priv, unicast_packet->dest)) {
if (is4addr) {
unicast_4addr_packet =
(struct batadv_unicast_4addr_packet *)skb->data;
subtype = unicast_4addr_packet->subtype;
batadv_dat_inc_counter(bat_priv, subtype);