**Describe what's wrong**

UDF functions are global objects. Creating or dropping them requires global level privilege.

- https://clickhouse.com/docs/en/sql-reference/statements/create/function/
- https://github.com/ClickHouse/ClickHouse/blob/14811a357e2136ff2940d791f2dbe59c65e87601/tests/integration/test_access_for_functions/test.py#L22

But "system.privileges" table reports DATABASE level for these privileges.

```
SELECT
    privilege,
    level
FROM system.privileges
WHERE CAST(privilege, 'text') LIKE '%FUNCTION%'

┌─privilege──────────────┬─level────┐
│ CREATE FUNCTION        │ DATABASE │
│ DROP FUNCTION          │ DATABASE │
│ SYSTEM RELOAD FUNCTION │ GLOBAL   │
└────────────────────────┴──────────┘
```

**Does it reproduce on recent release?**

Actual for the latest versions and master. In particular, for 21.12.4.1.

{
    if constexpr (grant_option)
    {
        return checkAccessImplHelper<throw_if_denied, true>(element);
    }
    else
    {
        if (element.grant_option)
            return checkAccessImplHelper<throw_if_denied, true>(element);
        else
            return checkAccessImplHelper<throw_if_denied, false>(element);
    }
}
template <bool throw_if_denied, bool grant_option>
bool ContextAccess::checkAccessImpl(const AccessRightsElements & elements) const
{
    for (const auto & element : elements)
        if (!checkAccessImpl<throw_if_denied, grant_option>(element))
            return false;
    return true;
}
bool ContextAccess::isGranted(const AccessFlags & flags) const { return checkAccessImpl<false, false>(flags); }
bool ContextAccess::isGranted(const AccessFlags & flags, const std::string_view & database) const { return checkAccessImpl<false, false>(flags, database); }
bool ContextAccess::isGranted(const AccessFlags & flags, const std::string_view & database, const std::string_view & table) const { return checkAccessImpl<false, false>(flags, database, table); }
bool ContextAccess::isGranted(const AccessFlags & flags, const std::string_view & database, const std::string_view & table, const std::string_view & column) const { return checkAccessImpl<false, false>(flags, database, table, column); }