如何确保VirtualAlloc分配的虚拟内存地址在2-4GB之间

Question

我试过使用while，但效果不是很好。有什么办法吗？

bool found = false;
uintptr_t memaddr = 0;
int n = 0;
while (!found && n < 10)
{
n += 1;
memaddr = (uintptr_t)VirtualAlloc(0, 4, MEM_COMMIT, PAGE_EXECUTE_READWRITE);
int g = memaddr / 1024 / 1024 / 1024;
cout << "memaddr: " << memaddr << endl;
if (g >= 2 && g <= 4)
{
found = true;
}
}
cout << hex << memaddr << endl;

Answer 1

使用VirtualAlloc的lpAddress参数

#include "pch.h"
#include <iostream>
#include <Windows.h>
#include <TlHelp32.h>
#include <Psapi.h>
using namespace std;
MODULEINFO GetModuleInfo(const wchar_t* name)
{
MODULEINFO mi{ 0 };
HMODULE hMod = GetModuleHandle(name);
GetModuleInformation(GetCurrentProcess(), hMod, &mi, sizeof(mi));
return mi;
}
MODULEINFO mi = GetModuleInfo(L"x64.exe");
BYTE* newmem = (BYTE*)VirtualAlloc((BYTE*)((uintptr_t)mi.lpBaseOfDll - 0x10000), 500, 
MEM_COMMIT | MEM_RESERVE, PAGE_EXECUTE_READWRITE);
cout << (uintptr_t)newmem / 1024 / 1024 / 1024 << endl;
BYTE* newmem2 = (BYTE*)VirtualAlloc((BYTE*)((uintptr_t)newmem - 0x10000), 4,
MEM_COMMIT | MEM_RESERVE, PAGE_EXECUTE_READWRITE);
if (newmem  != 0)  VirtualFree(newmem,  0,  MEM_RELEASE);
if (newmem2 != 0)  VirtualFree(newmem2, 0,  MEM_RELEASE);