xfrm: Handle blackhole route creation via afinfo.

That way we don't have to potentially do this in every xfrm_lookup()
caller.

Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 8 insertions, 13 deletions

diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index 23d205043d92..e24e4cf2a112 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -2675,12 +2675,10 @@ static struct dst_ops ipv4_dst_blackhole_ops = {
         .update_pmtu            =       ipv4_rt_blackhole_update_pmtu,
 };
 
-
-static int ipv4_dst_blackhole(struct net *net, struct rtable **rp, struct flowi *flp)
+struct dst_entry *ipv4_blackhole_route(struct net *net, struct dst_entry *dst_orig)
 {
-        struct rtable *ort = *rp;
-        struct rtable *rt = (struct rtable *)
-                dst_alloc(&ipv4_dst_blackhole_ops, 1);
+        struct rtable *rt = dst_alloc(&ipv4_dst_blackhole_ops, 1);
+        struct rtable *ort = (struct rtable *) dst_orig;
 
         if (rt) {
                 struct dst_entry *new = &rt->dst;
@@ -2714,9 +2712,9 @@ static int ipv4_dst_blackhole(struct net *net, struct rtable **rp, struct flowi
                 dst_free(new);
         }
 
-        dst_release(&(*rp)->dst);
-        *rp = rt;
-        return rt ? 0 : -ENOMEM;
+        dst_release(dst_orig);
+
+        return rt ? &rt->dst : ERR_PTR(-ENOMEM);
 }
 
 int ip_route_output_flow(struct net *net, struct rtable **rp, struct flowi *flp,
@@ -2732,11 +2730,7 @@ int ip_route_output_flow(struct net *net, struct rtable **rp, struct flowi *flp,
                         flp->fl4_src = (*rp)->rt_src;
                 if (!flp->fl4_dst)
                         flp->fl4_dst = (*rp)->rt_dst;
-                err = __xfrm_lookup(net, (struct dst_entry **)rp, flp, sk, 0);
-                if (err == -EREMOTE)
-                        err = ipv4_dst_blackhole(net, rp, flp);
-
-                return err;
+                return xfrm_lookup(net, (struct dst_entry **)rp, flp, sk, 0);
         }
 
         return 0;
diff --git a/net/ipv4/xfrm4_policy.c b/net/ipv4/xfrm4_policy.c
index 63aa88efdcef..5f0f058dc376 100644
--- a/net/ipv4/xfrm4_policy.c
+++ b/net/ipv4/xfrm4_policy.c
@@ -234,6 +234,7 @@ static struct xfrm_policy_afinfo xfrm4_policy_afinfo = {
         .get_tos =              xfrm4_get_tos,
         .init_path =            xfrm4_init_path,
         .fill_dst =             xfrm4_fill_dst,
+        .blackhole_route =      ipv4_blackhole_route,
 };
 
 #ifdef CONFIG_SYSCTL