ipv6: Remove all uses of LL_ALLOCATED_SPACE
ipv6: 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/ipv6
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/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
index 84d0bd5..68ef97f 100644
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -631,6 +631,7 @@
struct ipv6hdr *tmp_hdr;
struct frag_hdr *fh;
unsigned int mtu, hlen, left, len;
+ int hroom, troom;
__be32 frag_id = 0;
int ptr, offset = 0, err=0;
u8 *prevhdr, nexthdr = 0;
@@ -797,6 +798,8 @@
*/
*prevhdr = NEXTHDR_FRAGMENT;
+ hroom = LL_RESERVED_SPACE(rt->dst.dev);
+ troom = rt->dst.dev->needed_tailroom;
/*
* Keep copying data until we run out.
@@ -815,7 +818,8 @@
* Allocate buffer.
*/
- if ((frag = alloc_skb(len+hlen+sizeof(struct frag_hdr)+LL_ALLOCATED_SPACE(rt->dst.dev), GFP_ATOMIC)) == NULL) {
+ if ((frag = alloc_skb(len + hlen + sizeof(struct frag_hdr) +
+ hroom + troom, GFP_ATOMIC)) == NULL) {
NETDEBUG(KERN_INFO "IPv6: frag: no memory for new fragment!\n");
IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
IPSTATS_MIB_FRAGFAILS);
@@ -828,7 +832,7 @@
*/
ip6_copy_metadata(frag, skb);
- skb_reserve(frag, LL_RESERVED_SPACE(rt->dst.dev));
+ skb_reserve(frag, hroom);
skb_put(frag, len + hlen + sizeof(struct frag_hdr));
skb_reset_network_header(frag);
fh = (struct frag_hdr *)(skb_network_header(frag) + hlen);