diff --git a/net/netfilter/xt_IDLETIMER.c b/net/netfilter/xt_IDLETIMER.c
index f5e165e018d9..f06a5254dec2 100644
--- a/net/netfilter/xt_IDLETIMER.c
+++ b/net/netfilter/xt_IDLETIMER.c
@@ -70,6 +70,7 @@ struct idletimer_tg {
 	bool send_nl_msg;
 	bool active;
 	uid_t uid;
+	bool suspend_time_valid;
 };
 
 static LIST_HEAD(idletimer_tg_list);
@@ -239,8 +240,13 @@ static int idletimer_resume(struct notifier_block *notifier,
 	switch (pm_event) {
 	case PM_SUSPEND_PREPARE:
 		get_monotonic_boottime(&timer->last_suspend_time);
+		timer->suspend_time_valid = true;
 		break;
 	case PM_POST_SUSPEND:
+		if (!timer->suspend_time_valid)
+			break;
+		timer->suspend_time_valid = false;
+
 		spin_lock_bh(&timestamp_lock);
 		if (!timer->active) {
 			spin_unlock_bh(&timestamp_lock);
@@ -291,7 +297,7 @@ static int idletimer_tg_create(struct idletimer_tg_info *info)
 {
 	int ret;
 
-	info->timer = kmalloc(sizeof(*info->timer), GFP_KERNEL);
+	info->timer = kzalloc(sizeof(*info->timer), GFP_KERNEL);
 	if (!info->timer) {
 		ret = -ENOMEM;
 		goto out;