diff --git a/drivers/staging/batman-adv/routing.c b/drivers/staging/batman-adv/routing.c index d89048beebe16b7727e9de46cf9871cdedaea107..39dd093d7f2d5cd81bc79a81af705212a70038e5 100644 --- a/drivers/staging/batman-adv/routing.c +++ b/drivers/staging/batman-adv/routing.c @@ -549,6 +549,7 @@ int recv_bat_packet(struct sk_buff *skb, { struct ethhdr *ethhdr; unsigned long flags; + struct sk_buff *skb_old; /* drop packet if it has not necessary minimum size */ if (skb_headlen(skb) < sizeof(struct batman_packet)) @@ -564,12 +565,19 @@ int recv_bat_packet(struct sk_buff *skb, if (is_bcast(ethhdr->h_source)) return NET_RX_DROP; - spin_lock_irqsave(&orig_hash_lock, flags); /* TODO: we use headlen instead of "length", because * only this data is paged in. */ - /* TODO: is another skb_copy needed here? there will be - * written on the data, but nobody (?) should further use - * this data */ + + /* create a copy of the skb, if needed, to modify it. */ + if (!skb_clone_writable(skb, skb_headlen(skb))) { + skb_old = skb; + skb = skb_copy(skb, GFP_ATOMIC); + if (!skb) + return NET_RX_DROP; + kfree_skb(skb_old); + } + + spin_lock_irqsave(&orig_hash_lock, flags); receive_aggr_bat_packet(ethhdr, skb->data, skb_headlen(skb),