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>
This commit is contained in:
Herbert Xu
2011-11-18 02:20:04 +00:00
committed by David S. Miller
parent 505a467b66
commit 6608824329
4 changed files with 22 additions and 10 deletions

View File

@@ -592,16 +592,18 @@ struct sk_buff *arp_create(int type, int ptype, __be32 dest_ip,
struct sk_buff *skb;
struct arphdr *arp;
unsigned char *arp_ptr;
int hlen = LL_RESERVED_SPACE(dev);
int tlen = dev->needed_tailroom;
/*
* Allocate a buffer
*/
skb = alloc_skb(arp_hdr_len(dev) + LL_ALLOCATED_SPACE(dev), GFP_ATOMIC);
skb = alloc_skb(arp_hdr_len(dev) + hlen + tlen, GFP_ATOMIC);
if (skb == NULL)
return NULL;
skb_reserve(skb, LL_RESERVED_SPACE(dev));
skb_reserve(skb, hlen);
skb_reset_network_header(skb);
arp = (struct arphdr *) skb_put(skb, arp_hdr_len(dev));
skb->dev = dev;