ipv6: fix sparse warning on rt6i_node
Commit c5cff8561d2d adds rcu grace period before freeing fib6_node. This
generates a new sparse warning on rt->rt6i_node related code:
net/ipv6/route.c:1394:30: error: incompatible types in comparison
expression (different address spaces)
./include/net/ip6_fib.h:187:14: error: incompatible types in comparison
expression (different address spaces)
This commit adds "__rcu" tag for rt6i_node and makes sure corresponding
rcu API is used for it.
After this fix, sparse no longer generates the above warning.
Fixes: c5cff8561d2d ("ipv6: add rcu grace period before freeing fib6_node")
Signed-off-by: Wei Wang <weiwan@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/ip6_fib.c b/net/ipv6/ip6_fib.c
index a5ebf86..10b4b1f 100644
--- a/net/ipv6/ip6_fib.c
+++ b/net/ipv6/ip6_fib.c
@@ -889,7 +889,7 @@ static int fib6_add_rt2node(struct fib6_node *fn, struct rt6_info *rt,
rt->dst.rt6_next = iter;
*ins = rt;
- rt->rt6i_node = fn;
+ rcu_assign_pointer(rt->rt6i_node, fn);
atomic_inc(&rt->rt6i_ref);
if (!info->skip_notify)
inet6_rt_notify(RTM_NEWROUTE, rt, info, nlflags);
@@ -915,7 +915,7 @@ static int fib6_add_rt2node(struct fib6_node *fn, struct rt6_info *rt,
return err;
*ins = rt;
- rt->rt6i_node = fn;
+ rcu_assign_pointer(rt->rt6i_node, fn);
rt->dst.rt6_next = iter->dst.rt6_next;
atomic_inc(&rt->rt6i_ref);
if (!info->skip_notify)
@@ -1480,8 +1480,9 @@ static void fib6_del_route(struct fib6_node *fn, struct rt6_info **rtp,
int fib6_del(struct rt6_info *rt, struct nl_info *info)
{
+ struct fib6_node *fn = rcu_dereference_protected(rt->rt6i_node,
+ lockdep_is_held(&rt->rt6i_table->tb6_lock));
struct net *net = info->nl_net;
- struct fib6_node *fn = rt->rt6i_node;
struct rt6_info **rtp;
#if RT6_DEBUG >= 2
@@ -1670,7 +1671,9 @@ static int fib6_clean_node(struct fib6_walker *w)
if (res) {
#if RT6_DEBUG >= 2
pr_debug("%s: del failed: rt=%p@%p err=%d\n",
- __func__, rt, rt->rt6i_node, res);
+ __func__, rt,
+ rcu_access_pointer(rt->rt6i_node),
+ res);
#endif
continue;
}