net: ipv6: sit: fix rcu annotations

Fix minor __rcu annotations and remove sparse warnings

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/ipv6/sit.c b/net/ipv6/sit.c
index 8ce38f10a547e68fee50a9151cfb8727770bceda..b1599a345c107ecf2b293f5eea8bc29f277261d9 100644 (file)
--- a/net/ipv6/sit.c
+++ b/net/ipv6/sit.c
@@ -412,7 +412,7 @@ static void prl_list_destroy_rcu(struct rcu_head *head)
 
        p = container_of(head, struct ip_tunnel_prl_entry, rcu_head);
        do {
-               n = p->next;
+               n = rcu_dereference_protected(p->next, 1);
                kfree(p);
                p = n;
        } while (p);
@@ -421,15 +421,17 @@ static void prl_list_destroy_rcu(struct rcu_head *head)
 static int
 ipip6_tunnel_del_prl(struct ip_tunnel *t, struct ip_tunnel_prl *a)
 {
-       struct ip_tunnel_prl_entry *x, **p;
+       struct ip_tunnel_prl_entry *x;
+       struct ip_tunnel_prl_entry __rcu **p;
        int err = 0;
 
        ASSERT_RTNL();
 
        if (a && a->addr != htonl(INADDR_ANY)) {
-               for (p = &t->prl; *p; p = &(*p)->next) {
-                       if ((*p)->addr == a->addr) {
-                               x = *p;
+               for (p = &t->prl;
+                    (x = rtnl_dereference(*p)) != NULL;
+                    p = &x->next) {
+                       if (x->addr == a->addr) {
                                *p = x->next;
                                call_rcu(&x->rcu_head, prl_entry_destroy_rcu);
                                t->prl_count--;
@@ -438,9 +440,9 @@ ipip6_tunnel_del_prl(struct ip_tunnel *t, struct ip_tunnel_prl *a)
                }
                err = -ENXIO;
        } else {
-               if (t->prl) {
+               x = rtnl_dereference(t->prl);
+               if (x) {
                        t->prl_count = 0;
-                       x = t->prl;
                        call_rcu(&x->rcu_head, prl_list_destroy_rcu);
                        t->prl = NULL;
                }
@@ -1179,7 +1181,7 @@ static int __net_init ipip6_fb_tunnel_init(struct net_device *dev)
        if (!dev->tstats)
                return -ENOMEM;
        dev_hold(dev);
-       sitn->tunnels_wc[0]     = tunnel;
+       rcu_assign_pointer(sitn->tunnels_wc[0], tunnel);
        return 0;
 }
 
@@ -1196,11 +1198,12 @@ static void __net_exit sit_destroy_tunnels(struct sit_net *sitn, struct list_hea
        for (prio = 1; prio < 4; prio++) {
                int h;
                for (h = 0; h < HASH_SIZE; h++) {
-                       struct ip_tunnel *t = sitn->tunnels[prio][h];
+                       struct ip_tunnel *t;
 
+                       t = rtnl_dereference(sitn->tunnels[prio][h]);
                        while (t != NULL) {
                                unregister_netdevice_queue(t->dev, head);
-                               t = t->next;
+                               t = rtnl_dereference(t->next);
                        }
                }
        }