bluetooth: 6lowpan: use lowpan dispatch helpers

This patch adds a check if the dataroom of skb contains a dispatch value
by checking if skb->len != 0. This patch also change the dispatch
evaluation by the recently introduced helpers for checking the common
6LoWPAN dispatch values for IPv6 and IPHC header.

There was also a forgotten else branch which should drop the packet if
no matching dispatch is available.

Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Acked-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

diff --git a/net/bluetooth/6lowpan.c b/net/bluetooth/6lowpan.c
index db73b8a..665bf38 100644 (file)
--- a/net/bluetooth/6lowpan.c
+++ b/net/bluetooth/6lowpan.c
@@ -314,15 +314,17 @@ static int recv_pkt(struct sk_buff *skb, struct net_device *dev,
        if (!netif_running(dev))
                goto drop;
 
-       if (dev->type != ARPHRD_6LOWPAN)
+       if (dev->type != ARPHRD_6LOWPAN || !skb->len)
                goto drop;
 
+       skb_reset_network_header(skb);
+
        skb = skb_share_check(skb, GFP_ATOMIC);
        if (!skb)
                goto drop;
 
        /* check that it's our buffer */
-       if (skb->data[0] == LOWPAN_DISPATCH_IPV6) {
+       if (lowpan_is_ipv6(*skb_network_header(skb))) {
                /* Copy the packet so that the IPv6 header is
                 * properly aligned.
                 */
@@ -334,7 +336,6 @@ static int recv_pkt(struct sk_buff *skb, struct net_device *dev,
                local_skb->protocol = htons(ETH_P_IPV6);
                local_skb->pkt_type = PACKET_HOST;
 
-               skb_reset_network_header(local_skb);
                skb_set_transport_header(local_skb, sizeof(struct ipv6hdr));
 
                if (give_skb_to_upper(local_skb, dev) != NET_RX_SUCCESS) {
@@ -347,38 +348,34 @@ static int recv_pkt(struct sk_buff *skb, struct net_device *dev,
 
                consume_skb(local_skb);
                consume_skb(skb);
-       } else {
-               switch (skb->data[0] & 0xe0) {
-               case LOWPAN_DISPATCH_IPHC:      /* ipv6 datagram */
-                       local_skb = skb_clone(skb, GFP_ATOMIC);
-                       if (!local_skb)
-                               goto drop;
+       } else if (lowpan_is_iphc(*skb_network_header(skb))) {
+               local_skb = skb_clone(skb, GFP_ATOMIC);
+               if (!local_skb)
+                       goto drop;
 
-                       ret = iphc_decompress(local_skb, dev, chan);
-                       if (ret < 0) {
-                               kfree_skb(local_skb);
-                               goto drop;
-                       }
+               ret = iphc_decompress(local_skb, dev, chan);
+               if (ret < 0) {
+                       kfree_skb(local_skb);
+                       goto drop;
+               }
 
-                       local_skb->protocol = htons(ETH_P_IPV6);
-                       local_skb->pkt_type = PACKET_HOST;
-                       local_skb->dev = dev;
+               local_skb->protocol = htons(ETH_P_IPV6);
+               local_skb->pkt_type = PACKET_HOST;
+               local_skb->dev = dev;
 
-                       if (give_skb_to_upper(local_skb, dev)
-                                       != NET_RX_SUCCESS) {
-                               kfree_skb(local_skb);
-                               goto drop;
-                       }
+               if (give_skb_to_upper(local_skb, dev)
+                               != NET_RX_SUCCESS) {
+                       kfree_skb(local_skb);
+                       goto drop;
+               }
 
-                       dev->stats.rx_bytes += skb->len;
-                       dev->stats.rx_packets++;
+               dev->stats.rx_bytes += skb->len;
+               dev->stats.rx_packets++;
 
-                       consume_skb(local_skb);
-                       consume_skb(skb);
-                       break;
-               default:
-                       break;
-               }
+               consume_skb(local_skb);
+               consume_skb(skb);
+       } else {
+               goto drop;
        }
 
        return NET_RX_SUCCESS;