1 files changed, 24 insertions, 13 deletions

diff --git a/net/netfilter/xt_RATEEST.c b/net/netfilter/xt_RATEEST.c
index d80b8192e0d..370adf622ce 100644
--- a/net/netfilter/xt_RATEEST.c
+++ b/net/netfilter/xt_RATEEST.c
@@ -11,6 +11,7 @@
 #include <linux/jhash.h>
 #include <linux/rtnetlink.h>
 #include <linux/random.h>
+#include <linux/slab.h>
 #include <net/gen_stats.h>
 #include <net/netlink.h>
 
@@ -23,6 +24,7 @@ static DEFINE_MUTEX(xt_rateest_mutex);
 #define RATEEST_HSIZE	16
 static struct hlist_head rateest_hash[RATEEST_HSIZE] __read_mostly;
 static unsigned int jhash_rnd __read_mostly;
+static bool rnd_inited __read_mostly;
 
 static unsigned int xt_rateest_hash(const char *name)
 {
@@ -41,12 +43,11 @@ static void xt_rateest_hash_insert(struct xt_rateest *est)
 struct xt_rateest *xt_rateest_lookup(const char *name)
 {
 	struct xt_rateest *est;
-	struct hlist_node *n;
 	unsigned int h;
 
 	h = xt_rateest_hash(name);
 	mutex_lock(&xt_rateest_mutex);
-	hlist_for_each_entry(est, n, &rateest_hash[h], list) {
+	hlist_for_each_entry(est, &rateest_hash[h], list) {
 		if (strcmp(est->name, name) == 0) {
 			est->refcnt++;
 			mutex_unlock(&xt_rateest_mutex);
@@ -64,14 +65,18 @@ void xt_rateest_put(struct xt_rateest *est)
 	if (--est->refcnt == 0) {
 		hlist_del(&est->list);
 		gen_kill_estimator(&est->bstats, &est->rstats);
-		kfree(est);
+		/*
+		 * gen_estimator est_timer() might access est->lock or bstats,
+		 * wait a RCU grace period before freeing 'est'
+		 */
+		kfree_rcu(est, rcu);
 	}
 	mutex_unlock(&xt_rateest_mutex);
 }
 EXPORT_SYMBOL_GPL(xt_rateest_put);
 
 static unsigned int
-xt_rateest_tg(struct sk_buff *skb, const struct xt_target_param *par)
+xt_rateest_tg(struct sk_buff *skb, const struct xt_action_param *par)
 {
 	const struct xt_rateest_target_info *info = par->targinfo;
 	struct gnet_stats_basic_packed *stats = &info->est->bstats;
@@ -84,7 +89,7 @@ xt_rateest_tg(struct sk_buff *skb, const struct xt_target_param *par)
 	return XT_CONTINUE;
 }
 
-static bool xt_rateest_tg_checkentry(const struct xt_tgchk_param *par)
+static int xt_rateest_tg_checkentry(const struct xt_tgchk_param *par)
 {
 	struct xt_rateest_target_info *info = par->targinfo;
 	struct xt_rateest *est;
@@ -92,6 +97,12 @@ static bool xt_rateest_tg_checkentry(const struct xt_tgchk_param *par)
 		struct nlattr		opt;
 		struct gnet_estimator	est;
 	} cfg;
+	int ret;
+
+	if (unlikely(!rnd_inited)) {
+		get_random_bytes(&jhash_rnd, sizeof(jhash_rnd));
+		rnd_inited = true;
+	}
 
 	est = xt_rateest_lookup(info->name);
 	if (est) {
@@ -103,12 +114,13 @@ static bool xt_rateest_tg_checkentry(const struct xt_tgchk_param *par)
 		    (info->interval != est->params.interval ||
 		     info->ewma_log != est->params.ewma_log)) {
 			xt_rateest_put(est);
-			return false;
+			return -EINVAL;
 		}
 		info->est = est;
-		return true;
+		return 0;
 	}
 
+	ret = -ENOMEM;
 	est = kzalloc(sizeof(*est), GFP_KERNEL);
 	if (!est)
 		goto err1;
@@ -124,19 +136,19 @@ static bool xt_rateest_tg_checkentry(const struct xt_tgchk_param *par)
 	cfg.est.interval	= info->interval;
 	cfg.est.ewma_log	= info->ewma_log;
 
-	if (gen_new_estimator(&est->bstats, &est->rstats, &est->lock,
-			      &cfg.opt) < 0)
+	ret = gen_new_estimator(&est->bstats, &est->rstats,
+				&est->lock, &cfg.opt);
+	if (ret < 0)
 		goto err2;
 
 	info->est = est;
 	xt_rateest_hash_insert(est);
-
-	return true;
+	return 0;
 
 err2:
 	kfree(est);
 err1:
-	return false;
+	return ret;
 }
 
 static void xt_rateest_tg_destroy(const struct xt_tgdtor_param *par)
@@ -164,7 +176,6 @@ static int __init xt_rateest_tg_init(void)
 	for (i = 0; i < ARRAY_SIZE(rateest_hash); i++)
 		INIT_HLIST_HEAD(&rateest_hash[i]);
 
-	get_random_bytes(&jhash_rnd, sizeof(jhash_rnd));
 	return xt_register_target(&xt_rateest_tg_reg);
 }