net: Remove all uses of LL_ALLOCATED_SPACE

net: Remove all uses of LL_ALLOCATED_SPACE

The macro LL_ALLOCATED_SPACE was ill-conceived.  It applies the
alignment to the sum of needed_headroom and needed_tailroom.  As
the amount that is then reserved for head room is needed_headroom
with alignment, this means that the tail room left may be too small.

This patch replaces all uses of LL_ALLOCATED_SPACE with the macro
LL_RESERVED_SPACE and direct reference to needed_tailroom.

This also fixes the problem with needed_headroom changing between
allocating the skb and reserving the head room.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ieee802154/raw.c b/net/ieee802154/raw.c
index 10970ca..f96bae8 100644
--- a/net/ieee802154/raw.c
+++ b/net/ieee802154/raw.c
@@ -108,6 +108,7 @@
 	struct net_device *dev;
 	unsigned mtu;
 	struct sk_buff *skb;
+	int hlen, tlen;
 	int err;
 
 	if (msg->msg_flags & MSG_OOB) {
@@ -137,12 +138,14 @@
 		goto out_dev;
 	}
 
-	skb = sock_alloc_send_skb(sk, LL_ALLOCATED_SPACE(dev) + size,
+	hlen = LL_RESERVED_SPACE(dev);
+	tlen = dev->needed_tailroom;
+	skb = sock_alloc_send_skb(sk, hlen + tlen + size,
 			msg->msg_flags & MSG_DONTWAIT, &err);
 	if (!skb)
 		goto out_dev;
 
-	skb_reserve(skb, LL_RESERVED_SPACE(dev));
+	skb_reserve(skb, hlen);
 
 	skb_reset_mac_header(skb);
 	skb_reset_network_header(skb);