


Q: Given the following code slice:
```
CWE-457___CVE-2024-36930.c___1-55___51.c_vul.c
1 int spi_sync(struct spi_device *spi, struct spi_message *message)
3 	int ret;
5 	mutex_lock(&spi->controller->bus_lock_mutex);
6 	ret = __spi_sync(spi, message);
7 	mutex_unlock(&spi->controller->bus_lock_mutex);

```
which has a vulnerability among CWE-457 and among lines:
```
7 	mutex_unlock(&spi->controller->bus_lock_mutex);
```
Please generate five possible patches for the vulnerability.
A: The patch can be done in two steps.
Step 1. 