int propagate_mount_busy(struct mount *mnt, int refcnt)
{
	struct mount *m, *child;
	struct mount *parent = mnt->mnt_parent;
	int ret = 0;

	if (mnt == parent)
		return do_refcount_check(mnt, refcnt);

	/*
	 * quickly check if the current mount can be unmounted.
	 * If not, we don't have to go checking for all other
	 * mounts
	 */
	if (!list_empty(&mnt->mnt_mounts) || do_refcount_check(mnt, refcnt))
		return 1;

	for (m = propagation_next(parent, parent); m;
	     		m = propagation_next(m, parent)) {
		child = __lookup_mnt(&m->mnt, mnt->mnt_mountpoint, 0);
		if (child && list_empty(&child->mnt_mounts) &&
		    (ret = do_refcount_check(child, 1)))
			break;
	}
	return ret;
}

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