diff --git a/include/net/act_api.h b/include/net/act_api.h index 54fbb49bd08a..c61a1bf4e3de 100644 --- a/include/net/act_api.h +++ b/include/net/act_api.h @@ -39,7 +39,7 @@ struct tc_action { struct gnet_stats_basic_cpu __percpu *cpu_bstats_hw; struct gnet_stats_queue __percpu *cpu_qstats; struct tc_cookie __rcu *act_cookie; - struct tcf_chain *goto_chain; + struct tcf_chain __rcu *goto_chain; }; #define tcf_index common.tcfa_index #define tcf_refcnt common.tcfa_refcnt diff --git a/include/net/sch_generic.h b/include/net/sch_generic.h index 31284c078d06..7d1a0483a17b 100644 --- a/include/net/sch_generic.h +++ b/include/net/sch_generic.h @@ -378,6 +378,7 @@ struct tcf_chain { bool flushing; const struct tcf_proto_ops *tmplt_ops; void *tmplt_priv; + struct rcu_head rcu; }; struct tcf_block { 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); }