netfilter: Pass socket pointer down through okfn().
On the output paths in particular, we have to sometimes deal with two
socket contexts. First, and usually skb->sk, is the local socket that
generated the frame.
And second, is potentially the socket used to control a tunneling
socket, such as one the encapsulates using UDP.
We do not want to disassociate skb->sk when encapsulating in order
to fix this, because that would break socket memory accounting.
The most extreme case where this can cause huge problems is an
AF_PACKET socket transmitting over a vxlan device. We hit code
paths doing checks that assume they are dealing with an ipv4
socket, but are actually operating upon the AF_PACKET one.
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/xfrm6_output.c b/net/ipv6/xfrm6_output.c
index 010f8bd..09c76a7 100644
--- a/net/ipv6/xfrm6_output.c
+++ b/net/ipv6/xfrm6_output.c
@@ -120,7 +120,7 @@
}
EXPORT_SYMBOL(xfrm6_prepare_output);
-int xfrm6_output_finish(struct sk_buff *skb)
+int xfrm6_output_finish(struct sock *sk, struct sk_buff *skb)
{
memset(IP6CB(skb), 0, sizeof(*IP6CB(skb)));
@@ -128,10 +128,10 @@
IP6CB(skb)->flags |= IP6SKB_XFRM_TRANSFORMED;
#endif
- return xfrm_output(skb);
+ return xfrm_output(sk, skb);
}
-static int __xfrm6_output(struct sk_buff *skb)
+static int __xfrm6_output(struct sock *sk, struct sk_buff *skb)
{
struct dst_entry *dst = skb_dst(skb);
struct xfrm_state *x = dst->xfrm;
@@ -140,7 +140,7 @@
#ifdef CONFIG_NETFILTER
if (!x) {
IP6CB(skb)->flags |= IP6SKB_REROUTED;
- return dst_output(skb);
+ return dst_output_sk(sk, skb);
}
#endif
@@ -160,14 +160,15 @@
if (x->props.mode == XFRM_MODE_TUNNEL &&
((skb->len > mtu && !skb_is_gso(skb)) ||
dst_allfrag(skb_dst(skb)))) {
- return ip6_fragment(skb, x->outer_mode->afinfo->output_finish);
+ return ip6_fragment(sk, skb,
+ x->outer_mode->afinfo->output_finish);
}
- return x->outer_mode->afinfo->output_finish(skb);
+ return x->outer_mode->afinfo->output_finish(sk, skb);
}
int xfrm6_output(struct sock *sk, struct sk_buff *skb)
{
- return NF_HOOK_COND(NFPROTO_IPV6, NF_INET_POST_ROUTING, skb,
+ return NF_HOOK_COND(NFPROTO_IPV6, NF_INET_POST_ROUTING, sk, skb,
NULL, skb_dst(skb)->dev, __xfrm6_output,
!(IP6CB(skb)->flags & IP6SKB_REROUTED));
}