diff --git a/drivers/char/hw_random/core.c b/drivers/char/hw_random/core.c
index aa30a25c8d49..1500cfd799a7 100644
--- a/drivers/char/hw_random/core.c
+++ b/drivers/char/hw_random/core.c
@@ -281,7 +281,6 @@ static ssize_t hwrng_attr_available_show(struct device *dev,
 					 char *buf)
 {
 	int err;
-	ssize_t ret = 0;
 	struct hwrng *rng;
 
 	err = mutex_lock_interruptible(&rng_mutex);
@@ -289,16 +288,13 @@ static ssize_t hwrng_attr_available_show(struct device *dev,
 		return -ERESTARTSYS;
 	buf[0] = '\0';
 	list_for_each_entry(rng, &rng_list, list) {
-		strncat(buf, rng->name, PAGE_SIZE - ret - 1);
-		ret += strlen(rng->name);
-		strncat(buf, " ", PAGE_SIZE - ret - 1);
-		ret++;
+		strlcat(buf, rng->name, PAGE_SIZE);
+		strlcat(buf, " ", PAGE_SIZE);
 	}
-	strncat(buf, "\n", PAGE_SIZE - ret - 1);
-	ret++;
+	strlcat(buf, "\n", PAGE_SIZE);
 	mutex_unlock(&rng_mutex);
 
-	return ret;
+	return strlen(buf);
 }
 
 static DEVICE_ATTR(rng_current, S_IRUGO | S_IWUSR,