diff --git a/net/bluetooth/hci_debugfs.c b/net/bluetooth/hci_debugfs.c
index 6b7741f6e95b..233453807b50 100644
--- a/net/bluetooth/hci_debugfs.c
+++ b/net/bluetooth/hci_debugfs.c
@@ -1046,10 +1046,12 @@ static int min_key_size_set(void *data, u64 val)
 {
 	struct hci_dev *hdev = data;
 
-	if (val > hdev->le_max_key_size || val < SMP_MIN_ENC_KEY_SIZE)
-		return -EINVAL;
-
 	hci_dev_lock(hdev);
+	if (val > hdev->le_max_key_size || val < SMP_MIN_ENC_KEY_SIZE) {
+		hci_dev_unlock(hdev);
+		return -EINVAL;
+	}
+
 	hdev->le_min_key_size = val;
 	hci_dev_unlock(hdev);
 
@@ -1074,10 +1076,12 @@ static int max_key_size_set(void *data, u64 val)
 {
 	struct hci_dev *hdev = data;
 
-	if (val > SMP_MAX_ENC_KEY_SIZE || val < hdev->le_min_key_size)
-		return -EINVAL;
-
 	hci_dev_lock(hdev);
+	if (val > SMP_MAX_ENC_KEY_SIZE || val < hdev->le_min_key_size) {
+		hci_dev_unlock(hdev);
+		return -EINVAL;
+	}
+
 	hdev->le_max_key_size = val;
 	hci_dev_unlock(hdev);