Question

的信息：

.Net 4.5

经过测试：

Win7 64位
Win10 64位（虚拟盒）

我正在尝试获取外部进程的句柄列表并将其名称作为字符串返回，以便我可以在之后关闭特定的句柄。因此我使用Win32API编写了这个函数，它将检查句柄是否是我要关闭的句柄：`

        const int CNST_SYSTEM_HANDLE_INFORMATION = 16;
        const uint STATUS_INFO_LENGTH_MISMATCH = 0xc0000004;

        public static string getObjectTypeName(Win32API.SYSTEM_HANDLE_INFORMATION shHandle, Process process)
        {
            IntPtr m_ipProcessHwnd = Win32API.OpenProcess(Win32API.ProcessAccessFlags.All, false, process.Id);
            IntPtr ipHandle = IntPtr.Zero;
            var objBasic = new Win32API.OBJECT_BASIC_INFORMATION();
            IntPtr ipBasic = IntPtr.Zero;
            var objObjectType = new Win32API.OBJECT_TYPE_INFORMATION();
            IntPtr ipObjectType = IntPtr.Zero;
            IntPtr ipObjectName = IntPtr.Zero;
            string strObjectTypeName = "";
            int nLength = 0;
            int nReturn = 0;
            IntPtr ipTemp = IntPtr.Zero;


            if (!Win32API.DuplicateHandle(m_ipProcessHwnd, shHandle.Handle,
                                          Win32API.GetCurrentProcess(), out ipHandle,
                                          0, false, Win32API.DUPLICATE_SAME_ACCESS))
                return null;



            ipBasic = Marshal.AllocHGlobal(Marshal.SizeOf(objBasic));
            Win32API.NtQueryObject(ipHandle, (int)Win32API.ObjectInformationClass.ObjectBasicInformation,
                                   ipBasic, Marshal.SizeOf(objBasic), ref nLength);
            objBasic = (Win32API.OBJECT_BASIC_INFORMATION)Marshal.PtrToStructure(ipBasic, objBasic.GetType());
            Marshal.FreeHGlobal(ipBasic);

            ipObjectType = Marshal.AllocHGlobal(objBasic.TypeInformationLength);
            nLength = objBasic.TypeInformationLength;
            while ((uint)(nReturn = Win32API.NtQueryObject(
                ipHandle, (int)Win32API.ObjectInformationClass.ObjectTypeInformation, ipObjectType,
                  nLength, ref nLength)) ==
                Win32API.STATUS_INFO_LENGTH_MISMATCH)
            {
                Marshal.FreeHGlobal(ipObjectType);
                ipObjectType = Marshal.AllocHGlobal(nLength);
            }

            objObjectType = (Win32API.OBJECT_TYPE_INFORMATION)Marshal.PtrToStructure(ipObjectType, objObjectType.GetType());
            if (Is64Bits())
            {
                ipTemp = new IntPtr(Convert.ToInt64(objObjectType.Name.Buffer.ToString(), 10) >> 32);
            }
            else
            {
                ipTemp = objObjectType.Name.Buffer;
            }

        strObjectTypeName = Marshal.PtrToStringUni(ipTemp, objObjectType.Name.Length >> 1);


        Marshal.FreeHGlobal(ipObjectType);
            Win32API.CloseHandle(ipHandle);
            return strObjectTypeName;
        }`

问题是，此代码适用于Win7 64位，而不是Win10！ - ＆GT;在Win 10 strObjectTypeName = Marshal.PtrToStringUni();中抛出AcessViolationException（代码中的最后几行）

System.AccessViolationException尝试读取或写入受保护的内存。这通常表明其他内存已损坏。

我在这里错过了一些关于如何在win10中访问非托管内存的内容？

Answer 1

我刚遇到同样的问题。我没有尝试过Win7，但是当你在Win10（x64）上运行32位代码时（例如设置＆＃34;首选32位标志＆＃34;你的应用程序）它应该可以工作。当异常发生时，拖放变量＆＃34; ipTemp＆＃34;进入＆＃34;内存窗口＆＃34; Visual Studio，如果它只显示问号或错误消息，则表示您没有有效指针。据我所知，这个API使用的64位版本的结构中有（更多）填充字节： OBJECT_TYPE_INFORMATION包含UNICODE_STRING，并且UNICODE_STRING在64位模式下的缓冲区字段之前有4个填充字节。我的工作原理是：

[StructLayout(LayoutKind.Sequential, Pack = 1)]
public struct UNICODE_STRING
{
    private IntPtr _dummy; // the two ushorts seem to be padded with 4 bytes in 64bit mode only

    /// <summary>
    /// The length, in bytes, of the string stored in Buffer. If the string is null-terminated, Length does not include the trailing null character.
    /// </summary>
    public ushort Length
    {
        get { return (ushort)Marshal.ReadInt16(this, 0); }
    }

    /// <summary>
    /// The length, in bytes, of Buffer.
    /// </summary>
    public ushort MaximumLength
    {
        get { return (ushort)Marshal.ReadInt16(this, 2); }
    }

    public IntPtr Buffer;
}

在我的研究过程中，我发现了很多关于这个主题的问题，基本上是两种示例代码我正在考虑创建一个名为WinKernelObjectsDotNet的开源库。已经复制了整个Internet。

更新：该库现已可用here。它支持使用单行代码查找锁定文件或串行端口（COM）的进程。

Answer 2

我建议以这种方式更改UNICODE_STRING结构。

name

因此getObjectTypeName方法将类似于以下内容，并且适用于32/64：

    public struct UNICODE_STRING
    {
            public ushort Length;
            public ushort MaximumLength;
            [MarshalAs(UnmanagedType.LPWStr)] public string Buffer;
    }

C＃获取句柄列表，AcessViolationException

2 个答案: