ipv4: Remove all uses of LL_ALLOCATED_SPACE
ipv4: 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 in net/ipv4
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/ipv4/ipconfig.c b/net/ipv4/ipconfig.c
index 7f17ba8..915eb52 100644
--- a/net/ipv4/ipconfig.c
+++ b/net/ipv4/ipconfig.c
@@ -763,13 +763,15 @@
struct sk_buff *skb;
struct bootp_pkt *b;
struct iphdr *h;
+ int hlen = LL_RESERVED_SPACE(dev);
+ int tlen = dev->needed_tailroom;
/* Allocate packet */
- skb = alloc_skb(sizeof(struct bootp_pkt) + LL_ALLOCATED_SPACE(dev) + 15,
+ skb = alloc_skb(sizeof(struct bootp_pkt) + hlen + tlen + 15,
GFP_KERNEL);
if (!skb)
return;
- skb_reserve(skb, LL_RESERVED_SPACE(dev));
+ skb_reserve(skb, hlen);
b = (struct bootp_pkt *) skb_put(skb, sizeof(struct bootp_pkt));
memset(b, 0, sizeof(struct bootp_pkt));