Using eth_hdr() instead of skb->data avoids some ugly type casts.

I wasn't able to reproduce the skb ether header pointer mismatch mentioned in batadv_bla_tx() on a 3.11 kernel with a vlan on top of bat0 and therefore removed the according skb_reset_mac_header() call, too. Nevertheless I've added a check to the beginning of batadv_interface_tx() as I guess there might potentially be some device drivers not being that nice.

Signed-off-by: Linus Lüssing linus.luessing@web.de --- v2: added missing type cast

bridge_loop_avoidance.c | 3 --- soft-interface.c | 12 +++++++++--- 2 files changed, 9 insertions(+), 6 deletions(-)

diff --git a/bridge_loop_avoidance.c b/bridge_loop_avoidance.c index 5c0eda4..26ec489 100644 --- a/bridge_loop_avoidance.c +++ b/bridge_loop_avoidance.c @@ -1535,9 +1535,6 @@ int batadv_bla_tx(struct batadv_priv *bat_priv, struct sk_buff *skb, if (!atomic_read(&bat_priv->bridge_loop_avoidance)) goto allow;

- /* in VLAN case, the mac header might not be set. */ - skb_reset_mac_header(skb); - if (batadv_bla_process_claim(bat_priv, primary_if, skb)) goto handled;

diff --git a/soft-interface.c b/soft-interface.c index f82c267..fd7af1c 100644 --- a/soft-interface.c +++ b/soft-interface.c @@ -176,7 +176,13 @@ 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; + + if ((struct ethhdr *)skb->data != eth_hdr(skb)) { + pr_warn("Upper device did not set the ethernet header pointer correctly - adjusting\n"); + skb_reset_mac_header(skb); + } + + ethhdr = eth_hdr(skb);

switch (ntohs(ethhdr->h_proto)) { case ETH_P_8021Q: @@ -194,7 +200,7 @@ 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 +236,7 @@ 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 */