net: Correct comparisons and calculations using skb->tail and skb-transport_header

This corrects an regression introduced by "net: Use 16bits for *_headers
fields of struct skbuff" when NET_SKBUFF_DATA_USES_OFFSET is not set. In
that case skb->tail will be a pointer whereas skb->transport_header
will be an offset from head. This is corrected by using wrappers that
ensure that comparisons and calculations are always made using pointers.

Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Simon Horman
2013-05-28 20:34:25 +00:00
committed by David S. Miller
parent be8b678c6c
commit ced14f6804
2 changed files with 6 additions and 4 deletions

View File

@@ -134,12 +134,14 @@ static inline int INET_ECN_set_ce(struct sk_buff *skb)
{
switch (skb->protocol) {
case cpu_to_be16(ETH_P_IP):
if (skb->network_header + sizeof(struct iphdr) <= skb->tail)
if (skb_network_header(skb) + sizeof(struct iphdr) <=
skb_tail_pointer(skb))
return IP_ECN_set_ce(ip_hdr(skb));
break;
case cpu_to_be16(ETH_P_IPV6):
if (skb->network_header + sizeof(struct ipv6hdr) <= skb->tail)
if (skb_network_header(skb) + sizeof(struct ipv6hdr) <=
skb_tail_pointer(skb))
return IP6_ECN_set_ce(ipv6_hdr(skb));
break;
}