[XFRM]: beet: fix beet mode decapsulation

Beet mode decapsulation fails to properly set up the skb pointers, which
only works by accident in combination with CONFIG_NETFILTER, since in that
case the skb is fixed up in xfrm4_input before passing it to the netfilter
hooks.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/ipv4/xfrm4_mode_beet.c b/net/ipv4/xfrm4_mode_beet.c
index f8544b7..b94775a 100644 (file)
--- a/net/ipv4/xfrm4_mode_beet.c
+++ b/net/ipv4/xfrm4_mode_beet.c
@@ -83,24 +83,24 @@ static int xfrm4_beet_input(struct xfrm_state *x, struct sk_buff *skb)
                if (!pskb_may_pull(skb, sizeof(*ph)))
                        goto out;
 
-               phlen = ph->hdrlen * 8;
-               optlen = phlen - ph->padlen - sizeof(*ph);
+               phlen = sizeof(*ph) + ph->padlen;
+               optlen = ph->hdrlen * 8 - phlen;
                if (optlen < 0 || optlen & 3 || optlen > 250)
                        goto out;
 
-               if (!pskb_may_pull(skb, phlen))
+               if (!pskb_may_pull(skb, phlen + optlen))
                        goto out;
 
                ph_nexthdr = ph->nexthdr;
        }
 
-       skb_push(skb, sizeof(*iph) - phlen + optlen);
-       memmove(skb->data, skb->nh.raw, sizeof(*iph));
-       skb->nh.raw = skb->data;
+       skb->nh.raw = skb->data + (phlen - sizeof(*iph));
+       memmove(skb->nh.raw, iph, sizeof(*iph));
+       skb->h.raw = skb->data + (phlen + optlen);
 
        iph = skb->nh.iph;
        iph->ihl = (sizeof(*iph) + optlen) / 4;
-       iph->tot_len = htons(skb->len);
+       iph->tot_len = htons(skb->len + iph->ihl * 4);
        iph->daddr = x->sel.daddr.a4;
        iph->saddr = x->sel.saddr.a4;
        if (ph_nexthdr)