static int vmac_create(struct crypto_template *tmpl, struct rtattr **tb)
{
	struct shash_instance *inst;
	struct crypto_alg *alg;
	int err;

	err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_SHASH);
	if (err)
		return err;

	alg = crypto_get_attr_alg(tb, CRYPTO_ALG_TYPE_CIPHER,
			CRYPTO_ALG_TYPE_MASK);
	if (IS_ERR(alg))
		return PTR_ERR(alg);

	inst = shash_alloc_instance("vmac", alg);
	err = PTR_ERR(inst);
	if (IS_ERR(inst))
		goto out_put_alg;

	err = crypto_init_spawn(shash_instance_ctx(inst), alg,
			shash_crypto_instance(inst),
			CRYPTO_ALG_TYPE_MASK);
	if (err)
		goto out_free_inst;

	inst->alg.base.cra_priority = alg->cra_priority;
	inst->alg.base.cra_blocksize = alg->cra_blocksize;
	inst->alg.base.cra_alignmask = alg->cra_alignmask;

	inst->alg.digestsize = sizeof(vmac_t);
	inst->alg.base.cra_ctxsize = sizeof(struct vmac_ctx_t);
	inst->alg.base.cra_init = vmac_init_tfm;
	inst->alg.base.cra_exit = vmac_exit_tfm;

	inst->alg.init = vmac_init;
	inst->alg.update = vmac_update;
	inst->alg.final = vmac_final;
	inst->alg.setkey = vmac_setkey;

	err = shash_register_instance(tmpl, inst);
	if (err) {
out_free_inst:
		shash_free_instance(shash_crypto_instance(inst));
	}

out_put_alg:
	crypto_mod_put(alg);
	return err;
}

This category addresses vulnerabilities caused by flawed access control mechanisms, where incorrect permission settings allow unauthorized users to access restricted resources.