struct _HEAP_USERDATA_HEADER// Size=0x10
{
    struct _SINGLE_LIST_ENTRY SFreeListEntry;// Offset=0x0 Size=0x4
    struct _HEAP_SUBSEGMENT * SubSegment;// Offset=0x0 Size=0x4
    void * Reserved;// Offset=0x4 Size=0x4
    unsigned long SizeIndex;// Offset=0x8 Size=0x4
    unsigned long Signature;// Offset=0xc Size=0x4
};