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/igmp.c b/net/ipv4/igmp.c
index c7472ef..fbc5376 100644
--- a/net/ipv4/igmp.c
+++ b/net/ipv4/igmp.c
@@ -304,9 +304,11 @@
struct igmpv3_report *pig;
struct net *net = dev_net(dev);
struct flowi4 fl4;
+ int hlen = LL_RESERVED_SPACE(dev);
+ int tlen = dev->needed_tailroom;
while (1) {
- skb = alloc_skb(size + LL_ALLOCATED_SPACE(dev),
+ skb = alloc_skb(size + hlen + tlen,
GFP_ATOMIC | __GFP_NOWARN);
if (skb)
break;
@@ -327,7 +329,7 @@
skb_dst_set(skb, &rt->dst);
skb->dev = dev;
- skb_reserve(skb, LL_RESERVED_SPACE(dev));
+ skb_reserve(skb, hlen);
skb_reset_network_header(skb);
pip = ip_hdr(skb);
@@ -647,6 +649,7 @@
__be32 group = pmc ? pmc->multiaddr : 0;
struct flowi4 fl4;
__be32 dst;
+ int hlen, tlen;
if (type == IGMPV3_HOST_MEMBERSHIP_REPORT)
return igmpv3_send_report(in_dev, pmc);
@@ -661,7 +664,9 @@
if (IS_ERR(rt))
return -1;
- skb = alloc_skb(IGMP_SIZE+LL_ALLOCATED_SPACE(dev), GFP_ATOMIC);
+ hlen = LL_RESERVED_SPACE(dev);
+ tlen = dev->needed_tailroom;
+ skb = alloc_skb(IGMP_SIZE + hlen + tlen, GFP_ATOMIC);
if (skb == NULL) {
ip_rt_put(rt);
return -1;
@@ -669,7 +674,7 @@
skb_dst_set(skb, &rt->dst);
- skb_reserve(skb, LL_RESERVED_SPACE(dev));
+ skb_reserve(skb, hlen);
skb_reset_network_header(skb);
iph = ip_hdr(skb);