Q: Given the following code slice:
```
1 void rvu_npc_freemem(struct rvu *rvu)
4 	struct npc_mcam *mcam = &rvu->hw->mcam;
8 	kfree(mcam->counters.bmap);```
which has a CWE-401 vulnerability at line:
```
8 	kfree(mcam->counters.bmap);
```
Please analyze the root cause of the vulnerability.