Question

我试图从C＃中的进程中读取一些内存。这是我的辅助函数，用于从一系列偏移量中获取指针地址，以及相关的其他函数：

    [DllImport("kernel32.dll", CallingConvention = CallingConvention.StdCall, CharSet = CharSet.Auto, SetLastError = true)]
    public static extern Int32 ReadProcessMemory(
        IntPtr hProcess,
        IntPtr lpBaseAddress,
        [In, Out] byte[] buffer,
        UInt32 size,
        out int lpNumberOfBytesRead);

    public static bool ReadProcessMemoryHelper(
        IntPtr hProcess,
        long lpBaseAddress,
        [In, Out] byte[] buffer,
        UInt32 size,
        out int lpNumberOfBytesRead)
    {
        return ReadProcessMemory(
            hProcess,
            new IntPtr(lpBaseAddress),
            buffer,
            size,
            out lpNumberOfBytesRead) != 0;
    }
    public long Pointer(params int[] Offsets)
    {
        long pointerAddress = _baseAddr;

        if (Offsets.Length > 1)
        {
            byte[] buff = new byte[4];
            for (int i = 0; i < Offsets.Length - 1; i++)
            {
                int bytesRead;
                var cur = pointerAddress;
                var offset = Offsets[i];
                var next = cur + offset;
                Console.WriteLine("i = {0}", i);
                Console.WriteLine("[{0}+{1}], {2}", cur.ToString("X"), offset.ToString("X"), next.ToString("X"));

                if (0 == cur)
                {
                    return 0;
                }

                var readProcess = ReadProcessMemoryHelper(
                    _process.Handle,
                    next,
                    buff,
                    4,
                    out bytesRead);
                if (readProcess)
                {
                    pointerAddress = BitConverter.ToUInt32(buff, 0);
                }
                else
                {
                    return 0;
                }
                Console.WriteLine("i = {0}", i);
            }
        }

        return pointerAddress + Offsets[Offsets.Length - 1];
    }

神秘地说，在调用ReadProcessMemoryHelper之后，循环变量i变为0.这个循环只会终止，因为它最终无法从进程中读取内存，返回0。

以下是一些示例输出：

i = 0
[170000+FB02F0], 11202F0
i = 0
i = 1
[11469240+1C], 1146925C
i = 0
i = 1
[12DCC690+1C], 12DCC6AC
i = 0
i = 1
[114673A0+1C], 114673BC
i = 0
i = 1
[10F2C830+1C], 10F2C84C
i = 0
i = 1
[111561E0+1C], 111561FC
i = 0
i = 1
[E972CAE+1C], E972CCA
i = 0
i = 1
[1302736E+1C], 1302738A
i = 0
i = 1
[3E49+1C], 3E65

也许更神秘。这只发生在连接调试器时（谈论Heisenbug）。如果我从命令行运行它，我得到以下（正确的）输出：

i = 0
[170000+FB02F0], 11202F0
i = 0
i = 1
[11469240+1C], 1146925C
i = 1
i = 2
[12DCC690+10], 12DCC6A0
i = 2
i = 3
[113E4430+130], 113E4560
i = 3
i = 4
[10F2CEF0+1C], 10F2CF0C
i = 4

我不知道可能会做什么，这让我疯狂。

Answer 1

I'm going to take a guess that your process in 64-bit. If that is the case then the interop signature is incorrect as the size of the last parameter, lpNumberOfBytesRead should be 64-bits rather than 32-bits.

BOOL WINAPI ReadProcessMemory(
    _In_  HANDLE  hProcess,
    _In_  LPCVOID lpBaseAddress,
    _Out_ LPVOID  lpBuffer,
    _In_  SIZE_T  nSize,
    _Out_ SIZE_T  *lpNumberOfBytesRead);



#if defined(_WIN64)
typedef unsigned __int64 ULONG_PTR;
#else
typedef unsigned long ULONG_PTR;
#endif

typedef ULONG_PTR SIZE_T;

You can imagine how this would cause stack corruption. Since you ignore the out parameter anyways you could use an IntPtr in the signature.

循环变量（i）在Visual Studio中调试时在每个循环后神秘地重置为0（在不调试时工作）

1 个答案: