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>

1 files changed, 4 insertions, 2 deletions

diff --git a/net/core/netpoll.c b/net/core/netpoll.c
index cf64c1ffa4cd..1a7d8e2c9768 100644
--- a/net/core/netpoll.c
+++ b/net/core/netpoll.c
@@ -422,6 +422,7 @@ static void arp_reply(struct sk_buff *skb)
         struct sk_buff *send_skb;
         struct netpoll *np, *tmp;
         unsigned long flags;
+        int hlen, tlen;
         int hits = 0;
 
         if (list_empty(&npinfo->rx_np))
@@ -479,8 +480,9 @@ static void arp_reply(struct sk_buff *skb)
                 if (tip != np->local_ip)
                         continue;
 
-                send_skb = find_skb(np, size + LL_ALLOCATED_SPACE(np->dev),
-                                    LL_RESERVED_SPACE(np->dev));
+                hlen = LL_RESERVED_SPACE(np->dev);
+                tlen = np->dev->needed_tailroom;
+                send_skb = find_skb(np, size + hlen + tlen, hlen);
                 if (!send_skb)
                         continue;