From: Linus Lüssing linus.luessing@web.de
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 --- net/batman-adv/bridge_loop_avoidance.c | 2 +- net/batman-adv/distributed-arp-table.c | 5 +++++ net/batman-adv/gateway_client.c | 6 +++--- net/batman-adv/send.c | 11 +++++------ net/batman-adv/soft-interface.c | 8 ++++---- 5 files changed, 18 insertions(+), 14 deletions(-)
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 @@ static int batadv_bla_process_claim(struct batadv_priv *bat_priv, 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 @@ bool batadv_dat_snoop_incoming_arp_request(struct batadv_priv *bat_priv, 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 @@ batadv_gw_dhcp_recipient_get(struct sk_buff *skb, unsigned int *header_len, 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 @@ batadv_gw_dhcp_recipient_get(struct sk_buff *skb, unsigned int *header_len, 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 @@ batadv_gw_dhcp_recipient_get(struct sk_buff *skb, unsigned int *header_len, 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 @@ static int batadv_send_skb_unicast(struct batadv_priv *bat_priv, { 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 @@ static int batadv_send_skb_unicast(struct batadv_priv *bat_priv, 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 @@ static int batadv_send_skb_unicast(struct batadv_priv *bat_priv, 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..c4392fc 100644 --- a/net/batman-adv/soft-interface.c +++ b/net/batman-adv/soft-interface.c @@ -176,11 +176,11 @@ static int batadv_interface_tx(struct sk_buff *skb,
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 @@ static int batadv_interface_tx(struct sk_buff *skb, 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 @@ static int batadv_interface_tx(struct sk_buff *skb, /* 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 */