diff --git a/drivers/block/null_blk/main.c b/drivers/block/null_blk/main.c
index df85189f0b69..e063c931dfca 100644
--- a/drivers/block/null_blk/main.c
+++ b/drivers/block/null_blk/main.c
@@ -579,8 +579,13 @@ static ssize_t nullb_device_zone_readonly_store(struct config_item *item,
 						const char *page, size_t count)
 {
 	struct nullb_device *dev = to_nullb_device(item);
+	ssize_t ret;
 
-	return zone_cond_store(dev, page, count, BLK_ZONE_COND_READONLY);
+	mutex_lock(&lock);
+	ret = zone_cond_store(dev, page, count, BLK_ZONE_COND_READONLY);
+	mutex_unlock(&lock);
+
+	return ret;
 }
 CONFIGFS_ATTR_WO(nullb_device_, zone_readonly);
 
@@ -588,8 +593,13 @@ static ssize_t nullb_device_zone_offline_store(struct config_item *item,
 					       const char *page, size_t count)
 {
 	struct nullb_device *dev = to_nullb_device(item);
+	ssize_t ret;
 
-	return zone_cond_store(dev, page, count, BLK_ZONE_COND_OFFLINE);
+	mutex_lock(&lock);
+	ret = zone_cond_store(dev, page, count, BLK_ZONE_COND_OFFLINE);
+	mutex_unlock(&lock);
+
+	return ret;
 }
 CONFIGFS_ATTR_WO(nullb_device_, zone_offline);
 
@@ -836,7 +846,6 @@ static void null_free_dev(struct nullb_device *dev)
 	if (!dev)
 		return;
 
-	null_free_zoned_dev(dev);
 	badblocks_exit(&dev->badblocks);
 	kfree(dev);
 }
@@ -1777,6 +1786,7 @@ static void null_del_dev(struct nullb *nullb)
 	}
 
 	put_disk(nullb->disk);
+	null_free_zoned_dev(dev);
 	if (nullb->tag_set == &nullb->__tag_set)
 		blk_mq_free_tag_set(nullb->tag_set);
 	kfree(nullb->queues);