11 files changed, 32 insertions, 26 deletions

diff --git a/include/net/ip6_fib.h b/include/net/ip6_fib.h
index 20210d79e36a..d1327e4d126b 100644
--- a/include/net/ip6_fib.h
+++ b/include/net/ip6_fib.h
@@ -213,6 +213,15 @@ static inline void rt6_set_from(struct rt6_info *rt, struct rt6_info *from)
         dst_hold(new);
 }
 
+static inline void ip6_rt_put(struct rt6_info *rt)
+{
+        /* dst_release() accepts a NULL parameter.
+         * We rely on dst being first structure in struct rt6_info
+         */
+        BUILD_BUG_ON(offsetof(struct rt6_info, dst) != 0);
+        dst_release(&rt->dst);
+}
+
 struct fib6_walker_t {
         struct list_head lh;
         struct fib6_node *root, *node;
diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index ced58e1d91b6..fab23db8ee73 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -699,7 +699,7 @@ void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)
                 pr_warn("Freeing alive inet6 address %p\n", ifp);
                 return;
         }
-        dst_release(&ifp->rt->dst);
+        ip6_rt_put(ifp->rt);
 
         kfree_rcu(ifp, rcu);
 }
@@ -951,7 +951,7 @@ static void ipv6_del_addr(struct inet6_ifaddr *ifp)
                                 rt6_set_expires(rt, expires);
                         }
                 }
-                dst_release(&rt->dst);
+                ip6_rt_put(rt);
         }
 
         /* clean up prefsrc entries */
@@ -2027,8 +2027,7 @@ void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao)
                         addrconf_prefix_route(&pinfo->prefix, pinfo->prefix_len,
                                               dev, expires, flags);
                 }
-                if (rt)
-                        dst_release(&rt->dst);
+                ip6_rt_put(rt);
         }
 
         /* Try to figure out our local address for this prefix */
diff --git a/net/ipv6/anycast.c b/net/ipv6/anycast.c
index cdf02be5f191..4963c769a13f 100644
--- a/net/ipv6/anycast.c
+++ b/net/ipv6/anycast.c
@@ -84,7 +84,7 @@ int ipv6_sock_ac_join(struct sock *sk, int ifindex, const struct in6_addr *addr)
                 rt = rt6_lookup(net, addr, NULL, 0, 0);
                 if (rt) {
                         dev = rt->dst.dev;
-                        dst_release(&rt->dst);
+                        ip6_rt_put(rt);
                 } else if (ishost) {
                         err = -EADDRNOTAVAIL;
                         goto error;
diff --git a/net/ipv6/fib6_rules.c b/net/ipv6/fib6_rules.c
index d9fb9110f607..2e1a432867c0 100644
--- a/net/ipv6/fib6_rules.c
+++ b/net/ipv6/fib6_rules.c
@@ -100,7 +100,7 @@ static int fib6_rule_action(struct fib_rule *rule, struct flowi *flp,
                 goto out;
         }
 again:
-        dst_release(&rt->dst);
+        ip6_rt_put(rt);
         rt = NULL;
         goto out;
 
diff --git a/net/ipv6/ip6_gre.c b/net/ipv6/ip6_gre.c
index 0185679c5f53..bbe2e7b538b4 100644
--- a/net/ipv6/ip6_gre.c
+++ b/net/ipv6/ip6_gre.c
@@ -1069,7 +1069,7 @@ static void ip6gre_tnl_link_config(struct ip6_tnl *t, int set_mtu)
                                         dev->mtu = IPV6_MIN_MTU;
                         }
                 }
-                dst_release(&rt->dst);
+                ip6_rt_put(rt);
         }
 
         t->hlen = addend;
diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
index e10c77b4fbec..3deaa4e2e8e2 100644
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -755,7 +755,7 @@ int ip6_fragment(struct sk_buff *skb, int (*output)(struct sk_buff *))
                 if (err == 0) {
                         IP6_INC_STATS(net, ip6_dst_idev(&rt->dst),
                                       IPSTATS_MIB_FRAGOKS);
-                        dst_release(&rt->dst);
+                        ip6_rt_put(rt);
                         return 0;
                 }
 
@@ -767,7 +767,7 @@ int ip6_fragment(struct sk_buff *skb, int (*output)(struct sk_buff *))
 
                 IP6_INC_STATS(net, ip6_dst_idev(&rt->dst),
                               IPSTATS_MIB_FRAGFAILS);
-                dst_release(&rt->dst);
+                ip6_rt_put(rt);
                 return err;
 
 slow_path_clean:
diff --git a/net/ipv6/ip6_tunnel.c b/net/ipv6/ip6_tunnel.c
index cb7e2ded6f08..09482f723064 100644
--- a/net/ipv6/ip6_tunnel.c
+++ b/net/ipv6/ip6_tunnel.c
@@ -663,8 +663,7 @@ ip6ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 
                 icmpv6_send(skb2, rel_type, rel_code, rel_info);
 
-                if (rt)
-                        dst_release(&rt->dst);
+                ip6_rt_put(rt);
 
                 kfree_skb(skb2);
         }
@@ -1208,7 +1207,7 @@ static void ip6_tnl_link_config(struct ip6_tnl *t)
                         if (dev->mtu < IPV6_MIN_MTU)
                                 dev->mtu = IPV6_MIN_MTU;
                 }
-                dst_release(&rt->dst);
+                ip6_rt_put(rt);
         }
 }
 
diff --git a/net/ipv6/mcast.c b/net/ipv6/mcast.c
index 92f8e48e4ba4..b19ed51a45bb 100644
--- a/net/ipv6/mcast.c
+++ b/net/ipv6/mcast.c
@@ -163,7 +163,7 @@ int ipv6_sock_mc_join(struct sock *sk, int ifindex, const struct in6_addr *addr)
                 rt = rt6_lookup(net, addr, NULL, 0, 0);
                 if (rt) {
                         dev = rt->dst.dev;
-                        dst_release(&rt->dst);
+                        ip6_rt_put(rt);
                 }
         } else
                 dev = dev_get_by_index_rcu(net, ifindex);
@@ -260,7 +260,7 @@ static struct inet6_dev *ip6_mc_find_dev_rcu(struct net *net,
 
                 if (rt) {
                         dev = rt->dst.dev;
-                        dst_release(&rt->dst);
+                        ip6_rt_put(rt);
                 }
         } else
                 dev = dev_get_by_index_rcu(net, ifindex);
diff --git a/net/ipv6/ndisc.c b/net/ipv6/ndisc.c
index ff36194a71aa..ae0cf818a8f0 100644
--- a/net/ipv6/ndisc.c
+++ b/net/ipv6/ndisc.c
@@ -1145,7 +1145,7 @@ static void ndisc_router_discovery(struct sk_buff *skb)
                         ND_PRINTK(0, err,
                                   "RA: %s got default router without neighbour\n",
                                   __func__);
-                        dst_release(&rt->dst);
+                        ip6_rt_put(rt);
                         return;
                 }
         }
@@ -1170,7 +1170,7 @@ static void ndisc_router_discovery(struct sk_buff *skb)
                         ND_PRINTK(0, err,
                                   "RA: %s got default router without neighbour\n",
                                   __func__);
-                        dst_release(&rt->dst);
+                        ip6_rt_put(rt);
                         return;
                 }
                 neigh->flags |= NTF_ROUTER;
@@ -1326,8 +1326,7 @@ skip_routeinfo:
                 ND_PRINTK(2, warn, "RA: invalid RA options\n");
         }
 out:
-        if (rt)
-                dst_release(&rt->dst);
+        ip6_rt_put(rt);
         if (neigh)
                 neigh_release(neigh);
 }
diff --git a/net/ipv6/netfilter/ip6t_rpfilter.c b/net/ipv6/netfilter/ip6t_rpfilter.c
index 5d1d8b04d694..5060d54199ab 100644
--- a/net/ipv6/netfilter/ip6t_rpfilter.c
+++ b/net/ipv6/netfilter/ip6t_rpfilter.c
@@ -67,7 +67,7 @@ static bool rpfilter_lookup_reverse6(const struct sk_buff *skb,
         if (rt->rt6i_idev->dev == dev || (flags & XT_RPFILTER_LOOSE))
                 ret = true;
  out:
-        dst_release(&rt->dst);
+        ip6_rt_put(rt);
         return ret;
 }
 
diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index 9c7b5d800495..c1cfcb7e5632 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -732,7 +732,7 @@ int rt6_route_rcv(struct net_device *dev, u8 *opt, int len,
                 else
                         rt6_set_expires(rt, jiffies + HZ * lifetime);
 
-                dst_release(&rt->dst);
+                ip6_rt_put(rt);
         }
         return 0;
 }
@@ -948,7 +948,7 @@ restart:
         else
                 goto out2;
 
-        dst_release(&rt->dst);
+        ip6_rt_put(rt);
         rt = nrt ? : net->ipv6.ip6_null_entry;
 
         dst_hold(&rt->dst);
@@ -965,7 +965,7 @@ restart:
          * Race condition! In the gap, when table->tb6_lock was
          * released someone could insert this route.  Relookup.
          */
-        dst_release(&rt->dst);
+        ip6_rt_put(rt);
         goto relookup;
 
 out:
@@ -1576,7 +1576,7 @@ int ip6_route_add(struct fib6_config *cfg)
                                 goto out;
                         if (dev) {
                                 if (dev != grt->dst.dev) {
-                                        dst_release(&grt->dst);
+                                        ip6_rt_put(grt);
                                         goto out;
                                 }
                         } else {
@@ -1587,7 +1587,7 @@ int ip6_route_add(struct fib6_config *cfg)
                         }
                         if (!(grt->rt6i_flags & RTF_GATEWAY))
                                 err = 0;
-                        dst_release(&grt->dst);
+                        ip6_rt_put(grt);
 
                         if (err)
                                 goto out;
@@ -1673,7 +1673,7 @@ static int __ip6_del_rt(struct rt6_info *rt, struct nl_info *info)
         write_unlock_bh(&table->tb6_lock);
 
 out:
-        dst_release(&rt->dst);
+        ip6_rt_put(rt);
         return err;
 }
 
@@ -2732,7 +2732,7 @@ static int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr* nlh, void
 
         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
         if (!skb) {
-                dst_release(&rt->dst);
+                ip6_rt_put(rt);
                 err = -ENOBUFS;
                 goto errout;
         }