Repository : ssh://git@open-mesh.org/batman-adv

On branch : next

commit a6ad8574ea13f3463bae39324d093e6c31682cc8 Author: Simon Wunderlich simon.wunderlich@s2003.tu-chemnitz.de Date: Sun Oct 14 14:46:57 2012 +0200

batman-adv: dirty hack to recompute mac_len in the rx path

It is possible that the mac_len is not properly exported because of strange device configuration (this behaviour has been observed when using batman-adv on top of a vlan interface). Therefore it is needed to explicitly recompute it at the very beginning of the rx path.

This is done by appending the recompute function to the skb_share_mac() function, hence the "dirty hack" in the subject. We expect this problem to be fixed in linux 3.8 and above.

Reported-by: Antonio Quartulli ordex@autistici.org Signed-off-by: Simon Wunderlich siwu@hrz.tu-chemnitz.de Signed-off-by: Marek Lindner lindner_marek@yahoo.de

a6ad8574ea13f3463bae39324d093e6c31682cc8 compat.h | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+)

diff --git a/compat.h b/compat.h index 13253dd..081bef5 100644 --- a/compat.h +++ b/compat.h @@ -145,6 +145,11 @@ void batadv_free_rcu_neigh_node(struct rcu_head *rcu); void batadv_free_rcu_tt_local_entry(struct rcu_head *rcu); void batadv_free_rcu_backbone_gw(struct rcu_head *rcu);

+static inline void skb_reset_mac_len(struct sk_buff *skb) +{ + skb->mac_len = skb->network_header - skb->mac_header; +} + #endif /* < KERNEL_VERSION(3, 0, 0) */

@@ -157,4 +162,23 @@ static inline void eth_hw_addr_random(struct net_device *dev)

#endif /* < KERNEL_VERSION(3, 4, 0) */

+#if LINUX_VERSION_CODE < KERNEL_VERSION(3, 8, 0) + +/* hack for not correctly set mac_len. This may happen for some special + * configurations like batman-adv on VLANs. + * + * This is pretty dirty, but we only use skb_share_check() in main.c right + * before mac_len is checked, and the recomputation shouldn't hurt too much. + */ +#define skb_share_check(skb, b) \ + ({ \ + struct sk_buff *_t_skb; \ + _t_skb = skb_share_check(skb, b); \ + if (_t_skb) \ + skb_reset_mac_len(_t_skb); \ + _t_skb; \ + }) + +#endif /* < KERNEL_VERSION(3, 8, 0) */ + #endif /* _NET_BATMAN_ADV_COMPAT_H_ */