2 files changed, 11 insertions, 9 deletions

diff --git a/net/sched/act_api.c b/net/sched/act_api.c
index fe67b98ac641..5a87e271d35a 100644
--- a/net/sched/act_api.c
+++ b/net/sched/act_api.c
@@ -31,7 +31,7 @@
 static void tcf_action_goto_chain_exec(const struct tc_action *a,
 				       struct tcf_result *res)
 {
-	const struct tcf_chain *chain = a->goto_chain;
+	const struct tcf_chain *chain = rcu_dereference_bh(a->goto_chain);
 
 	res->goto_tp = rcu_dereference_bh(chain->filter_chain);
 }
@@ -91,13 +91,11 @@ end:
 EXPORT_SYMBOL(tcf_action_check_ctrlact);
 
 struct tcf_chain *tcf_action_set_ctrlact(struct tc_action *a, int action,
-					 struct tcf_chain *newchain)
+					 struct tcf_chain *goto_chain)
 {
-	struct tcf_chain *oldchain = a->goto_chain;
-
 	a->tcfa_action = action;
-	a->goto_chain = newchain;
-	return oldchain;
+	rcu_swap_protected(a->goto_chain, goto_chain, 1);
+	return goto_chain;
 }
 EXPORT_SYMBOL(tcf_action_set_ctrlact);
 
@@ -108,7 +106,7 @@ EXPORT_SYMBOL(tcf_action_set_ctrlact);
  */
 static void free_tcf(struct tc_action *p)
 {
-	struct tcf_chain *chain = p->goto_chain;
+	struct tcf_chain *chain = rcu_dereference_protected(p->goto_chain, 1);
 
 	free_percpu(p->cpu_bstats);
 	free_percpu(p->cpu_bstats_hw);
@@ -686,6 +684,10 @@ repeat:
 					return TC_ACT_OK;
 			}
 		} else if (TC_ACT_EXT_CMP(ret, TC_ACT_GOTO_CHAIN)) {
+			if (unlikely(!rcu_access_pointer(a->goto_chain))) {
+				net_warn_ratelimited("can't go to NULL chain!\n");
+				return TC_ACT_SHOT;
+			}
 			tcf_action_goto_chain_exec(a, res);
 		}
 
@@ -931,7 +933,7 @@ struct tc_action *tcf_action_init_1(struct net *net, struct tcf_proto *tp,
 		module_put(a_o->owner);
 
 	if (TC_ACT_EXT_CMP(a->tcfa_action, TC_ACT_GOTO_CHAIN) &&
-	    !a->goto_chain) {
+	    !rcu_access_pointer(a->goto_chain)) {
 		tcf_action_destroy_1(a, bind);
 		NL_SET_ERR_MSG(extack, "can't use goto chain with NULL chain");
 		return ERR_PTR(-EINVAL);
diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c
index dc10525e90e7..99ae30c177c7 100644
--- a/net/sched/cls_api.c
+++ b/net/sched/cls_api.c
@@ -367,7 +367,7 @@ static void tcf_chain_destroy(struct tcf_chain *chain, bool free_block)
 	struct tcf_block *block = chain->block;
 
 	mutex_destroy(&chain->filter_chain_lock);
-	kfree(chain);
+	kfree_rcu(chain, rcu);
 	if (free_block)
 		tcf_block_destroy(block);
 }