1 files changed, 36 insertions, 52 deletions

diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c
index 09bfcbac63bb..b5e665b3cfb0 100644
--- a/net/xfrm/xfrm_policy.c
+++ b/net/xfrm/xfrm_policy.c
@@ -303,6 +303,14 @@ struct xfrm_policy *xfrm_policy_alloc(struct net *net, gfp_t gfp)
 }
 EXPORT_SYMBOL(xfrm_policy_alloc);
 
+static void xfrm_policy_destroy_rcu(struct rcu_head *head)
+{
+	struct xfrm_policy *policy = container_of(head, struct xfrm_policy, rcu);
+
+	security_xfrm_policy_free(policy->security);
+	kfree(policy);
+}
+
 /* Destroy xfrm_policy: descendant resources must be released to this moment. */
 
 void xfrm_policy_destroy(struct xfrm_policy *policy)
@@ -312,8 +320,7 @@ void xfrm_policy_destroy(struct xfrm_policy *policy)
 	if (del_timer(&policy->timer) || del_timer(&policy->polq.hold_timer))
 		BUG();
 
-	security_xfrm_policy_free(policy->security);
-	kfree(policy);
+	call_rcu(&policy->rcu, xfrm_policy_destroy_rcu);
 }
 EXPORT_SYMBOL(xfrm_policy_destroy);
 
@@ -1214,8 +1221,10 @@ static struct xfrm_policy *xfrm_sk_policy_lookup(const struct sock *sk, int dir,
 	struct xfrm_policy *pol;
 	struct net *net = sock_net(sk);
 
+	rcu_read_lock();
 	read_lock_bh(&net->xfrm.xfrm_policy_lock);
-	if ((pol = sk->sk_policy[dir]) != NULL) {
+	pol = rcu_dereference(sk->sk_policy[dir]);
+	if (pol != NULL) {
 		bool match = xfrm_selector_match(&pol->selector, fl,
 						 sk->sk_family);
 		int err = 0;
@@ -1239,6 +1248,7 @@ static struct xfrm_policy *xfrm_sk_policy_lookup(const struct sock *sk, int dir,
 	}
 out:
 	read_unlock_bh(&net->xfrm.xfrm_policy_lock);
+	rcu_read_unlock();
 	return pol;
 }
 
@@ -1307,13 +1317,14 @@ int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol)
 #endif
 
 	write_lock_bh(&net->xfrm.xfrm_policy_lock);
-	old_pol = sk->sk_policy[dir];
-	sk->sk_policy[dir] = pol;
+	old_pol = rcu_dereference_protected(sk->sk_policy[dir],
+				lockdep_is_held(&net->xfrm.xfrm_policy_lock));
 	if (pol) {
 		pol->curlft.add_time = get_seconds();
 		pol->index = xfrm_gen_index(net, XFRM_POLICY_MAX+dir, 0);
 		xfrm_sk_policy_link(pol, dir);
 	}
+	rcu_assign_pointer(sk->sk_policy[dir], pol);
 	if (old_pol) {
 		if (pol)
 			xfrm_policy_requeue(old_pol, pol);
@@ -1361,17 +1372,26 @@ static struct xfrm_policy *clone_policy(const struct xfrm_policy *old, int dir)
 	return newp;
 }
 
-int __xfrm_sk_clone_policy(struct sock *sk)
+int __xfrm_sk_clone_policy(struct sock *sk, const struct sock *osk)
 {
-	struct xfrm_policy *p0 = sk->sk_policy[0],
-			   *p1 = sk->sk_policy[1];
+	const struct xfrm_policy *p;
+	struct xfrm_policy *np;
+	int i, ret = 0;
 
-	sk->sk_policy[0] = sk->sk_policy[1] = NULL;
-	if (p0 && (sk->sk_policy[0] = clone_policy(p0, 0)) == NULL)
-		return -ENOMEM;
-	if (p1 && (sk->sk_policy[1] = clone_policy(p1, 1)) == NULL)
-		return -ENOMEM;
-	return 0;
+	rcu_read_lock();
+	for (i = 0; i < 2; i++) {
+		p = rcu_dereference(osk->sk_policy[i]);
+		if (p) {
+			np = clone_policy(p, i);
+			if (unlikely(!np)) {
+				ret = -ENOMEM;
+				break;
+			}
+			rcu_assign_pointer(sk->sk_policy[i], np);
+		}
+	}
+	rcu_read_unlock();
+	return ret;
 }
 
 static int
@@ -2198,6 +2218,7 @@ struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig,
 	xdst = NULL;
 	route = NULL;
 
+	sk = sk_const_to_full_sk(sk);
 	if (sk && sk->sk_policy[XFRM_POLICY_OUT]) {
 		num_pols = 1;
 		pols[0] = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl);
@@ -2477,6 +2498,7 @@ int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb,
 	}
 
 	pol = NULL;
+	sk = sk_to_full_sk(sk);
 	if (sk && sk->sk_policy[dir]) {
 		pol = xfrm_sk_policy_lookup(sk, dir, &fl);
 		if (IS_ERR(pol)) {
@@ -2804,7 +2826,6 @@ static struct neighbour *xfrm_neigh_lookup(const struct dst_entry *dst,
 
 int xfrm_policy_register_afinfo(struct xfrm_policy_afinfo *afinfo)
 {
-	struct net *net;
 	int err = 0;
 	if (unlikely(afinfo == NULL))
 		return -EINVAL;
@@ -2835,26 +2856,6 @@ int xfrm_policy_register_afinfo(struct xfrm_policy_afinfo *afinfo)
 	}
 	spin_unlock(&xfrm_policy_afinfo_lock);
 
-	rtnl_lock();
-	for_each_net(net) {
-		struct dst_ops *xfrm_dst_ops;
-
-		switch (afinfo->family) {
-		case AF_INET:
-			xfrm_dst_ops = &net->xfrm.xfrm4_dst_ops;
-			break;
-#if IS_ENABLED(CONFIG_IPV6)
-		case AF_INET6:
-			xfrm_dst_ops = &net->xfrm.xfrm6_dst_ops;
-			break;
-#endif
-		default:
-			BUG();
-		}
-		*xfrm_dst_ops = *afinfo->dst_ops;
-	}
-	rtnl_unlock();
-
 	return err;
 }
 EXPORT_SYMBOL(xfrm_policy_register_afinfo);
@@ -2890,22 +2891,6 @@ int xfrm_policy_unregister_afinfo(struct xfrm_policy_afinfo *afinfo)
 }
 EXPORT_SYMBOL(xfrm_policy_unregister_afinfo);
 
-static void __net_init xfrm_dst_ops_init(struct net *net)
-{
-	struct xfrm_policy_afinfo *afinfo;
-
-	rcu_read_lock();
-	afinfo = rcu_dereference(xfrm_policy_afinfo[AF_INET]);
-	if (afinfo)
-		net->xfrm.xfrm4_dst_ops = *afinfo->dst_ops;
-#if IS_ENABLED(CONFIG_IPV6)
-	afinfo = rcu_dereference(xfrm_policy_afinfo[AF_INET6]);
-	if (afinfo)
-		net->xfrm.xfrm6_dst_ops = *afinfo->dst_ops;
-#endif
-	rcu_read_unlock();
-}
-
 static int xfrm_dev_event(struct notifier_block *this, unsigned long event, void *ptr)
 {
 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
@@ -3054,7 +3039,6 @@ static int __net_init xfrm_net_init(struct net *net)
 	rv = xfrm_policy_init(net);
 	if (rv < 0)
 		goto out_policy;
-	xfrm_dst_ops_init(net);
 	rv = xfrm_sysctl_init(net);
 	if (rv < 0)
 		goto out_sysctl;