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/raw.c b/net/ipv6/raw.c
index eedff8c..4f8886a 100644
--- a/net/ipv6/raw.c
+++ b/net/ipv6/raw.c
@@ -1132,7 +1132,8 @@
spin_lock_bh(&sk->sk_receive_queue.lock);
skb = skb_peek(&sk->sk_receive_queue);
if (skb != NULL)
- amount = skb->tail - skb->transport_header;
+ amount = skb_tail_pointer(skb) -
+ skb_transport_header(skb);
spin_unlock_bh(&sk->sk_receive_queue.lock);
return put_user(amount, (int __user *)arg);
}