AllocAtHighestUserAddressBuffer

ulonglong AllocAtHighestUserAddressBuffer()
{
#define HighestUserAddress          0x7FFFFFFF0000
#define HighestUserAddressBuffer    0x7FFFFFFEF000
#define PageSize                    0x1000


    ulonglong Base = 0x7FFFFFFEF000;
    ulonglong RegionSize = 0x1000;
    int retV = ZwAllocateVirtualMemory(GetCurrentProcess(),&Base,0,&RegionSize,MEM_RESERVE,PAGE_READWRITE);
    printf("ZwAllocateVirtualMemory, ret: %X, Base: %I64X Size: %I64X\r\n",retV,Base,RegionSize);
    if(retV >= 0)
    {
        retV = ZwAllocateVirtualMemory(GetCurrentProcess(),&Base,0,&RegionSize,MEM_COMMIT,PAGE_READWRITE);
        printf("ZwAllocateVirtualMemory, ret: %X, Base: %I64X Size: %I64X\r\n",retV,Base,RegionSize);

        *(uchar*)(HighestUserAddressBuffer+0xFFF) = 0;
        return Base;
    }
    return 0;
}