Q: Given the following code slice:
```
1 static int32_t
6 	uint32_t size;
8 	struct app_sinfo_req	app_req;
9 	struct app_stats_reply	*app_reply;
10 	uint32_t pcnt = 0;
23 	size = sizeof(struct app_stats_reply) +
26 	app_reply = kzalloc(size, GFP_KERNEL);
27 	if (!app_reply) {
31 		struct fc_port	*fcport = NULL, *tf;
36 			if (fcport->edif.enable) {
37 				if (pcnt > app_req.num_ports)```
which has a CWE-125 vulnerability at line:
```
40 				app_reply->elem[pcnt].rekey_count =
```
Please analyze the root cause of the vulnerability.