batman-adv: use vlan_/eth_hdr() instead of skb->data in interface_tx path
Our .ndo_start_xmit handler (batadv_interface_tx()) can rely on having
the skb mac header pointer set correctly since the following commit
present in kernels >= 3.9:
"net: reset mac header in dev_start_xmit()" (6d1ccff627)
Therefore we can safely use eth_hdr() and vlan_eth_hdr() instead of
skb->data now, which spares us some ugly type casts.
At the same time set the mac_header in batadv_dat_snoop_incoming_arp_request()
before sending the skb along the TX path.
Signed-off-by: Linus Lüssing <linus.luessing@web.de>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <antonio@meshcoding.com>
diff --git a/net/batman-adv/bridge_loop_avoidance.c b/net/batman-adv/bridge_loop_avoidance.c
index 05f0712..73d8372 100644
--- a/net/batman-adv/bridge_loop_avoidance.c
+++ b/net/batman-adv/bridge_loop_avoidance.c
@@ -882,7 +882,7 @@
proto = ethhdr->h_proto;
headlen = ETH_HLEN;
if (vid & BATADV_VLAN_HAS_TAG) {
- vhdr = (struct vlan_ethhdr *)ethhdr;
+ vhdr = vlan_eth_hdr(skb);
proto = vhdr->h_vlan_encapsulated_proto;
headlen += VLAN_HLEN;
}
diff --git a/net/batman-adv/distributed-arp-table.c b/net/batman-adv/distributed-arp-table.c
index edee504..5bb37a8 100644
--- a/net/batman-adv/distributed-arp-table.c
+++ b/net/batman-adv/distributed-arp-table.c
@@ -1027,6 +1027,11 @@
if (!skb_new)
goto out;
+ /* the rest of the TX path assumes that the mac_header offset pointing
+ * to the inner Ethernet header has been set, therefore reset it now.
+ */
+ skb_reset_mac_header(skb_new);
+
if (vid & BATADV_VLAN_HAS_TAG)
skb_new = vlan_insert_tag(skb_new, htons(ETH_P_8021Q),
vid & VLAN_VID_MASK);
diff --git a/net/batman-adv/gateway_client.c b/net/batman-adv/gateway_client.c
index d7fafc1..07c7f21 100644
--- a/net/batman-adv/gateway_client.c
+++ b/net/batman-adv/gateway_client.c
@@ -678,7 +678,7 @@
if (!pskb_may_pull(skb, *header_len + ETH_HLEN))
return BATADV_DHCP_NO;
- ethhdr = (struct ethhdr *)skb->data;
+ ethhdr = eth_hdr(skb);
proto = ethhdr->h_proto;
*header_len += ETH_HLEN;
@@ -687,7 +687,7 @@
if (!pskb_may_pull(skb, *header_len + VLAN_HLEN))
return BATADV_DHCP_NO;
- vhdr = (struct vlan_ethhdr *)skb->data;
+ vhdr = vlan_eth_hdr(skb);
proto = vhdr->h_vlan_encapsulated_proto;
*header_len += VLAN_HLEN;
}
@@ -726,7 +726,7 @@
return BATADV_DHCP_NO;
/* skb->data might have been reallocated by pskb_may_pull() */
- ethhdr = (struct ethhdr *)skb->data;
+ ethhdr = eth_hdr(skb);
if (ntohs(ethhdr->h_proto) == ETH_P_8021Q)
ethhdr = (struct ethhdr *)(skb->data + VLAN_HLEN);
diff --git a/net/batman-adv/send.c b/net/batman-adv/send.c
index 843febd..1703a2e 100644
--- a/net/batman-adv/send.c
+++ b/net/batman-adv/send.c
@@ -256,7 +256,7 @@
{
struct ethhdr *ethhdr;
struct batadv_unicast_packet *unicast_packet;
- int ret = NET_XMIT_DROP, hdr_size;
+ int ret = NET_XMIT_DROP;
if (!orig_node)
goto out;
@@ -265,16 +265,12 @@
case BATADV_UNICAST:
if (!batadv_send_skb_prepare_unicast(skb, orig_node))
goto out;
-
- hdr_size = sizeof(*unicast_packet);
break;
case BATADV_UNICAST_4ADDR:
if (!batadv_send_skb_prepare_unicast_4addr(bat_priv, skb,
orig_node,
packet_subtype))
goto out;
-
- hdr_size = sizeof(struct batadv_unicast_4addr_packet);
break;
default:
/* this function supports UNICAST and UNICAST_4ADDR only. It
@@ -283,7 +279,10 @@
goto out;
}
- ethhdr = (struct ethhdr *)(skb->data + hdr_size);
+ /* skb->data might have been reallocated by
+ * batadv_send_skb_prepare_unicast{,_4addr}()
+ */
+ ethhdr = eth_hdr(skb);
unicast_packet = (struct batadv_unicast_packet *)skb->data;
/* inform the destination node that we are still missing a correct route
diff --git a/net/batman-adv/soft-interface.c b/net/batman-adv/soft-interface.c
index f82c267..c4392fcd 100644
--- a/net/batman-adv/soft-interface.c
+++ b/net/batman-adv/soft-interface.c
@@ -176,11 +176,11 @@
soft_iface->trans_start = jiffies;
vid = batadv_get_vid(skb, 0);
- ethhdr = (struct ethhdr *)skb->data;
+ ethhdr = eth_hdr(skb);
switch (ntohs(ethhdr->h_proto)) {
case ETH_P_8021Q:
- vhdr = (struct vlan_ethhdr *)skb->data;
+ vhdr = vlan_eth_hdr(skb);
if (vhdr->h_vlan_encapsulated_proto != ethertype)
break;
@@ -194,7 +194,7 @@
goto dropped;
/* skb->data might have been reallocated by batadv_bla_tx() */
- ethhdr = (struct ethhdr *)skb->data;
+ ethhdr = eth_hdr(skb);
/* Register the client MAC in the transtable */
if (!is_multicast_ether_addr(ethhdr->h_source)) {
@@ -230,7 +230,7 @@
/* skb->data may have been modified by
* batadv_gw_dhcp_recipient_get()
*/
- ethhdr = (struct ethhdr *)skb->data;
+ ethhdr = eth_hdr(skb);
/* if gw_mode is on, broadcast any non-DHCP message.
* All the DHCP packets are going to be sent as unicast
*/