From: Matthias Schiffer <mschiffer@xxxxxxxxxxxxxxxxxxxx>
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: 7cdcf6dddc42 ("batman-adv: add UNICAST_4ADDR packet type")
Signed-off-by: Matthias Schiffer <mschiffer@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sven Eckelmann <sven@xxxxxxxxxxxxx>
Signed-off-by: Simon Wunderlich <sw@xxxxxxxxxxxxxxxxxx>
---
net/batman-adv/routing.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)
diff --git a/net/batman-adv/routing.c b/net/batman-adv/routing.c
index cd82cff716c7..f59aac06733e 100644
--- a/net/batman-adv/routing.c
+++ b/net/batman-adv/routing.c
@@ -950,14 +950,10 @@ int batadv_recv_unicast_packet(struct sk_buff *skb,
struct batadv_orig_node *orig_node = NULL, *orig_node_gw = NULL;
int check, hdr_size = sizeof(*unicast_packet);
enum batadv_subtype subtype;
- struct ethhdr *ethhdr;
int ret = NET_RX_DROP;
bool is4addr, is_gw;
unicast_packet = (struct batadv_unicast_packet *)skb->data;
- unicast_4addr_packet = (struct batadv_unicast_4addr_packet *)skb->data;
- ethhdr = eth_hdr(skb);
-
is4addr = unicast_packet->packet_type == BATADV_UNICAST_4ADDR;
/* the caller function should have already pulled 2 bytes */
if (is4addr)
@@ -977,12 +973,14 @@ int batadv_recv_unicast_packet(struct sk_buff *skb,
if (!batadv_check_unicast_ttvn(bat_priv, skb, hdr_size))
goto free_skb;
+ unicast_packet = (struct batadv_unicast_packet *)skb->data;
+
/* packet for me */
if (batadv_is_my_mac(bat_priv, unicast_packet->dest)) {
/* If this is a unicast packet from another backgone gw,
* drop it.
*/
- orig_addr_gw = ethhdr->h_source;
+ orig_addr_gw = eth_hdr(skb)->h_source;
orig_node_gw = batadv_orig_hash_find(bat_priv, orig_addr_gw);
if (orig_node_gw) {
is_gw = batadv_bla_is_backbone_gw(skb, orig_node_gw,
@@ -997,6 +995,8 @@ int batadv_recv_unicast_packet(struct sk_buff *skb,
}
if (is4addr) {
+ unicast_4addr_packet =
+ (struct batadv_unicast_4addr_packet *)skb->data;
subtype = unicast_4addr_packet->subtype;
batadv_dat_inc_counter(bat_priv, subtype);
--
2.20.1
