batman-adv: check for tt_reponse packet real length
Before accessing the TT_RESPONSE packet payload, the node has to ensure that the
packet is long enough as it would expect to be.
Reported-by: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
diff --git a/net/batman-adv/routing.c b/net/batman-adv/routing.c
index e0e7b7b..ef24a72 100644
--- a/net/batman-adv/routing.c
+++ b/net/batman-adv/routing.c
@@ -578,6 +578,7 @@
{
struct bat_priv *bat_priv = netdev_priv(recv_if->soft_iface);
struct tt_query_packet *tt_query;
+ uint16_t tt_len;
struct ethhdr *ethhdr;
/* drop packet if it has not necessary minimum size */
@@ -622,6 +623,14 @@
if (skb_linearize(skb) < 0)
goto out;
+ tt_len = tt_query->tt_data * sizeof(struct tt_change);
+
+ /* Ensure we have all the claimed data */
+ if (unlikely(skb_headlen(skb) <
+ sizeof(struct tt_query_packet) +
+ tt_len))
+ goto out;
+
handle_tt_response(bat_priv, tt_query);
} else {
bat_dbg(DBG_TT, bat_priv,