Re: [PATCH v27 0/9] MR3103: server: Create and use a desktop shared mapping for GetCursorPos.

[Jinoh Kang (＠iamahuman)]

Jinoh Kang (@iamahuman) commented about server/mapping.c:
> - {
> -
>    shared->obj.id = ++session.last_object_id;
> - }
> - SHARED_WRITE_END;
> - session.next_object_index = index + 1;
> -
> - return index;
>
> +}
> -
>
> +void free_shared_object( int index )
> +{
> - if (index < 0) return;
> -
> - SHARED_WRITE_BEGIN( &session.shared->objects[index], session_obj_t )
> - {
> -
>    shared->obj.id = 0;

We're releasing the object unscrubbed. A future `alloc_shared_object()` call will return uninitialized memory, with leftover contents from previous allocation.[^1]

```suggestion:-0+0
        memset( (char *)shared + offsetof(session_obj_t, obj.id), 0, sizeof(*shared) - offsetof(session_obj_t, obj.id) );
```

[^1]: This means that e.g., queues will reuse memory from inputs, once we introduce other kinds of shared objects.