Why does HeapFree() not working as it should?

Question

I created implementation in MVS without using CRT. I use HeapAlloc() and HeapFree() for allocating memory. My example should work without memory leak.
Here is my code:

LPCSTR byte2ch(BYTE* data, int size) {
    char* datas = (char*)HeapAlloc(GetProcessHeap(), NULL, size);
    LPCSTR temp = (reinterpret_cast<char const*>(data));
    for (int i = 0; i < size; i++) {
        datas[i] = temp[i];
    }
    LPSTR tempo = datas;
    HeapFree(GetProcessHeap(), NULL, (LPVOID)&size);
    return tempo;
}

int EntryPoint()
{
    BYTE* buffer = 0;

    HANDLE hFile;
    DWORD dwBytesRead, dwBytesWritten, dwPos;

    if (hFile = CreateFileW(L"MinerFinder.exe", GENERIC_READ | GENERIC_WRITE, 0, NULL, OPEN_ALWAYS, 0, NULL))
    {
        LARGE_INTEGER size;
        GetFileSizeEx(hFile, &size);

        buffer = (BYTE*)HeapAlloc(GetProcessHeap(), NULL, size.QuadPart);
        ReadFile(hFile, buffer, size.QuadPart, &dwBytesRead, NULL);

        MessageBoxA(NULL, byte2ch(buffer, size.QuadPart), NULL, SW_SHOW);
        HeapFree(GetProcessHeap(), NULL, (LPVOID)&size.QuadPart);
        MessageBoxA(NULL, "", NULL, SW_SHOW); // there I can see, that memory is leaking...
        CloseHandle(hFile);
    }

    ExitProcess(0);
}  

Where is my mistake?

EDIT 1:

LPCSTR byte2ch(BYTE* data, int size) {
        char* datas = (char*)HeapAlloc(GetProcessHeap(), NULL, size);
        LPCSTR temp = (reinterpret_cast<char const*>(data));
        for (int i = 0; i < size; i++) {
            datas[i] = temp[i];
        }
        LPSTR tempo = datas;
        HeapFree(GetProcessHeap(), NULL, datas);
        return tempo;
    }

there when I HeapFree() program suddenly crashes. What?

Answer 1

Looking at HeapFree

BOOL HeapFree( HANDLE hHeap, DWORD dwFlags, _Frees_ptr_opt_ LPVOID lpMem );

lpMem

A pointer to the memory block to be freed. This pointer is returned by the HeapAlloc or HeapReAlloc function. If this pointer is NULL, the behavior is undefined.

---

In the code

HeapFree(GetProcessHeap(), NULL, (LPVOID)&size);
HeapFree(GetProcessHeap(), NULL, (LPVOID)&size.QuadPart);

You don't give an allocated pointer to HeapFree, but a pointer to the address of some unrelated (non-heap) memory.

---

The proper call would be

HeapFree(GetProcessHeap(), NULL, datas);

or

HeapFree(GetProcessHeap(), NULL, buffer);