X-Git-Url: https://git.kernel.dk/?a=blobdiff_plain;f=net%2Fipv4%2Froute.c;h=278f46f5011beb2ab85747543f84dfd3ce7c6d1c;hb=59ed6eecff4aa00c5c5d18ffd180acac108d596e;hp=cd76b3cb70925fc142c50f652adea2eafc5c7eb2;hpb=48ec2b53fe6a7244d62c74876ae00b0d7e03b4c5;p=linux-2.6-block.git

diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index cd76b3cb7092..278f46f5011b 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -1085,8 +1085,35 @@ restart:
 	now = jiffies;
 
 	if (!rt_caching(dev_net(rt->u.dst.dev))) {
-		rt_drop(rt);
-		return 0;
+		/*
+		 * If we're not caching, just tell the caller we
+		 * were successful and don't touch the route.  The
+		 * caller hold the sole reference to the cache entry, and
+		 * it will be released when the caller is done with it.
+		 * If we drop it here, the callers have no way to resolve routes
+		 * when we're not caching.  Instead, just point *rp at rt, so
+		 * the caller gets a single use out of the route
+		 * Note that we do rt_free on this new route entry, so that
+		 * once its refcount hits zero, we are still able to reap it
+		 * (Thanks Alexey)
+		 * Note also the rt_free uses call_rcu.  We don't actually
+		 * need rcu protection here, this is just our path to get
+		 * on the route gc list.
+		 */
+
+		if (rt->rt_type == RTN_UNICAST || rt->fl.iif == 0) {
+			int err = arp_bind_neighbour(&rt->u.dst);
+			if (err) {
+				if (net_ratelimit())
+					printk(KERN_WARNING
+					    "Neighbour table failure & not caching routes.\n");
+				rt_drop(rt);
+				return err;
+			}
+		}
+
+		rt_free(rt);
+		goto skip_hashing;
 	}
 
 	rthp = &rt_hash_table[hash].chain;
@@ -1203,7 +1230,8 @@ restart:
 #if RT_CACHE_DEBUG >= 2
 	if (rt->u.dst.rt_next) {
 		struct rtable *trt;
-		printk(KERN_DEBUG "rt_cache @%02x: %pI4", hash, &rt->rt_dst);
+		printk(KERN_DEBUG "rt_cache @%02x: %pI4",
+		       hash, &rt->rt_dst);
 		for (trt = rt->u.dst.rt_next; trt; trt = trt->u.dst.rt_next)
 			printk(" . %pI4", &trt->rt_dst);
 		printk("\n");
@@ -1217,6 +1245,8 @@ restart:
 	rcu_assign_pointer(rt_hash_table[hash].chain, rt);
 
 	spin_unlock_bh(rt_hash_lock_addr(hash));
+
+skip_hashing:
 	if (rp)
 		*rp = rt;
 	else