Bluetooth: hci_ll: Fix firmware leak on error path

Smatch reports:

drivers/bluetooth/hci_ll.c:587 download_firmware() warn:
'fw' from request_firmware() not released on lines: 544.

In download_firmware(), if request_firmware() succeeds but the returned
firmware content is invalid (no data or zero size), the function returns
without releasing the firmware, resulting in a resource leak.

Fix this by calling release_firmware() before returning when
request_firmware() succeeded but the firmware content is invalid.

Fixes: 3718055 ("bluetooth: hci_uart: add LL protocol serdev driver support")
Reviewed-by: Paul Menzel <[email protected]>
Signed-off-by: Anas Iqbal <[email protected]>
Signed-off-by: Luiz Augusto von Dentz <[email protected]>

Author: iqbalcodes6602

drivers/bluetooth/hci_ll.c

@@ -541,6 +541,8 @@ static int download_firmware(struct ll_device *lldev)
 	if (err || !fw->data || !fw->size) {
 		bt_dev_err(lldev->hu.hdev, "request_firmware failed(errno %d) for %s",
 			   err, bts_scr_name);
+		if (!err)
+			release_firmware(fw);
 		return -EINVAL;
 	}
 	ptr = (void *)fw->data;