


Q: Given the following code slice:
```
CWE-190___CVE-2024-36031.c___1-54___43.c_vul.c
1 static int __key_instantiate_and_link(struct key *key,
2 				      struct key_preparsed_payload *prep,
7 	int ret, awaken;
13 	ret = -EBUSY;
18 	if (key->state == KEY_IS_UNINSTANTIATED) {
20 		ret = key->type->instantiate(key, prep);
22 		if (ret == 0) {
43 			key_set_expiry(key, prep->expiry);

```
which has a vulnerability among CWE-190 and among lines:
```
43 			key_set_expiry(key, prep->expiry);
```
Please generate five possible patches for the vulnerability.
A: The patch can be done in two steps.
Step 1. 