ipv6: 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>
diff --git a/net/ipv6/mip6.c b/net/ipv6/mip6.c
index 0f9bdc5..9ac01dc 100644
--- a/net/ipv6/mip6.c
+++ b/net/ipv6/mip6.c
@@ -268,7 +268,8 @@
struct ipv6_opt_hdr *exthdr =
(struct ipv6_opt_hdr *)(ipv6_hdr(skb) + 1);
const unsigned char *nh = skb_network_header(skb);
- unsigned int packet_len = skb->tail - skb->network_header;
+ unsigned int packet_len = skb_tail_pointer(skb) -
+ skb_network_header(skb);
int found_rhdr = 0;
*nexthdr = &ipv6_hdr(skb)->nexthdr;
@@ -404,7 +405,8 @@
struct ipv6_opt_hdr *exthdr =
(struct ipv6_opt_hdr *)(ipv6_hdr(skb) + 1);
const unsigned char *nh = skb_network_header(skb);
- unsigned int packet_len = skb->tail - skb->network_header;
+ unsigned int packet_len = skb_tail_pointer(skb) -
+ skb_network_header(skb);
int found_rhdr = 0;
*nexthdr = &ipv6_hdr(skb)->nexthdr;