1 files changed, 15 insertions, 9 deletions

diff --git a/net/ipv6/tunnel6.c b/net/ipv6/tunnel6.c
index d9864725d0c6..4f3cec12aa85 100644
--- a/net/ipv6/tunnel6.c
+++ b/net/ipv6/tunnel6.c
@@ -30,23 +30,26 @@
 #include <net/protocol.h>
 #include <net/xfrm.h>
 
-static struct xfrm6_tunnel *tunnel6_handlers __read_mostly;
-static struct xfrm6_tunnel *tunnel46_handlers __read_mostly;
+static struct xfrm6_tunnel __rcu *tunnel6_handlers __read_mostly;
+static struct xfrm6_tunnel __rcu *tunnel46_handlers __read_mostly;
 static DEFINE_MUTEX(tunnel6_mutex);
 
 int xfrm6_tunnel_register(struct xfrm6_tunnel *handler, unsigned short family)
 {
-        struct xfrm6_tunnel **pprev;
+        struct xfrm6_tunnel __rcu **pprev;
+        struct xfrm6_tunnel *t;
         int ret = -EEXIST;
         int priority = handler->priority;
 
         mutex_lock(&tunnel6_mutex);
 
         for (pprev = (family == AF_INET6) ? &tunnel6_handlers : &tunnel46_handlers;
-             *pprev; pprev = &(*pprev)->next) {
-                if ((*pprev)->priority > priority)
+             (t = rcu_dereference_protected(*pprev,
+                        lockdep_is_held(&tunnel6_mutex))) != NULL;
+             pprev = &t->next) {
+                if (t->priority > priority)
                         break;
-                if ((*pprev)->priority == priority)
+                if (t->priority == priority)
                         goto err;
         }
 
@@ -65,14 +68,17 @@ EXPORT_SYMBOL(xfrm6_tunnel_register);
 
 int xfrm6_tunnel_deregister(struct xfrm6_tunnel *handler, unsigned short family)
 {
-        struct xfrm6_tunnel **pprev;
+        struct xfrm6_tunnel __rcu **pprev;
+        struct xfrm6_tunnel *t;
         int ret = -ENOENT;
 
         mutex_lock(&tunnel6_mutex);
 
         for (pprev = (family == AF_INET6) ? &tunnel6_handlers : &tunnel46_handlers;
-             *pprev; pprev = &(*pprev)->next) {
-                if (*pprev == handler) {
+             (t = rcu_dereference_protected(*pprev,
+                        lockdep_is_held(&tunnel6_mutex))) != NULL;
+             pprev = &t->next) {
+                if (t == handler) {
                         *pprev = handler->next;
                         ret = 0;
                         break;