[PATCH net-next-2.6] tunnels: missing rcu_assign_pointer()

[Eric Dumazet <eric.dumazet@gmail.com>]

xfrm4_tunnel_register() & xfrm6_tunnel_register() should
use rcu_assign_pointer() to make sure previous writes
(to handler->next) are committed to memory before chain
insertion.

deregister functions dont need a particular barrier.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
---
No risk of crash, because handler->next is NULL before register()
call, but a possibility of packet being dropped.

 net/ipv4/tunnel4.c |    2 +-
 net/ipv6/tunnel6.c |    2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/net/ipv4/tunnel4.c b/net/ipv4/tunnel4.c
index df59d16..9a17bd2 100644
--- a/net/ipv4/tunnel4.c
+++ b/net/ipv4/tunnel4.c
@@ -39,7 +39,7 @@ int xfrm4_tunnel_register(struct xfrm_tunnel *handler, unsigned short family)
 	}
 
 	handler->next = *pprev;
-	*pprev = handler;
+	rcu_assign_pointer(*pprev, handler);
 
 	ret = 0;
 
diff --git a/net/ipv6/tunnel6.c b/net/ipv6/tunnel6.c
index 3177fe0..d986472 100644
--- a/net/ipv6/tunnel6.c
+++ b/net/ipv6/tunnel6.c
@@ -51,7 +51,7 @@ int xfrm6_tunnel_register(struct xfrm6_tunnel *handler, unsigned short family)
 	}
 
 	handler->next = *pprev;
-	*pprev = handler;
+	rcu_assign_pointer(*pprev, handler);
 
 	ret = 0;