ipv4: 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 20:34:27 +00:00 committed by David S. Miller
parent 29a3cad5c6
commit f7c0c2ae84
3 changed files with 5 additions and 3 deletions

View File

@ -503,7 +503,8 @@ void icmp_send(struct sk_buff *skb_in, int type, int code, __be32 info)
iph = ip_hdr(skb_in);
if ((u8 *)iph < skb_in->head ||
(skb_in->network_header + sizeof(*iph)) > skb_in->tail)
(skb_network_header(skb_in) + sizeof(*iph)) >
skb_tail_pointer(skb_in))
goto out;
/*

View File

@ -363,7 +363,7 @@ static struct sk_buff *igmpv3_newpack(struct net_device *dev, int size)
static int igmpv3_sendpack(struct sk_buff *skb)
{
struct igmphdr *pig = igmp_hdr(skb);
const int igmplen = skb->tail - skb->transport_header;
const int igmplen = skb_tail_pointer(skb) - skb_transport_header(skb);
pig->csum = ip_compute_csum(igmp_hdr(skb), igmplen);

View File

@ -2989,7 +2989,8 @@ struct sk_buff *tcp_tso_segment(struct sk_buff *skb,
swap(gso_skb->truesize, skb->truesize);
}
delta = htonl(oldlen + (skb->tail - skb->transport_header) +
delta = htonl(oldlen + (skb_tail_pointer(skb) -
skb_transport_header(skb)) +
skb->data_len);
th->check = ~csum_fold((__force __wsum)((__force u32)th->check +
(__force u32)delta));