Staging: batman-adv: Don't dereference unchecked incoming soft_iface

send_packet derefenced forw_packet->if_incoming and checked if
forw_packet->if_incoming is NULL.

This cannot happen, but still makes irritates when reading through the
functions.
Reported-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Sven Eckelmann <sven.eckelmann@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/staging/batman-adv/send.c

@@ -160,8 +160,8 @@ static void send_packet_to_if(struct forw_packet *forw_packet,
 static void send_packet(struct forw_packet *forw_packet)
 {
 	struct batman_if *batman_if;
-	struct net_device *soft_iface = forw_packet->if_incoming->soft_iface;
-	struct bat_priv *bat_priv = netdev_priv(soft_iface);
+	struct net_device *soft_iface;
+	struct bat_priv *bat_priv;
 	struct batman_packet *batman_packet =
 		(struct batman_packet *)(forw_packet->skb->data);
 	unsigned char directlink = (batman_packet->flags & DIRECTLINK ? 1 : 0);
@@ -172,6 +172,9 @@ static void send_packet(struct forw_packet *forw_packet)
 		return;
 	}
 
+	soft_iface = forw_packet->if_incoming->soft_iface;
+	bat_priv = netdev_priv(soft_iface);
+
 	if (forw_packet->if_incoming->if_status != IF_ACTIVE)
 		return;