const struct nf_conntrack_tuple *tuple,
enum nf_nat_manip_type maniptype)
{
- struct gre_hdr *greh;
+ const struct gre_hdr *greh;
struct gre_hdr_pptp *pgreh;
const struct iphdr *iph = (struct iphdr *)(skb->data + iphdroff);
unsigned int hdroff = iphdroff + iph->ihl * 4;