与我的其他问题相关，请帮助我调试“未知模块中发生'System.AccessViolationException'类型的未处理异常。附加信息：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。” 单步执行代码，一切正常，直到实际调用 del() 并在该行中失败。
此代码基于本文的示例和此在 python 中工作的python 代码。我也无法让代码示例按原样工作（同样的例外），但我希望它只是有点过时了。
编辑：如果您关心我们是如何到达这里的，请查看编辑历史，这很无趣。
完成的工作版本：
public static class CpuID
{
public static byte[] Invoke(int level)
{
IntPtr codePointer = IntPtr.Zero;
try
{
// compile
byte[] codeBytes;
if (IntPtr.Size == 4)
{
codeBytes = x86CodeBytes;
}
else
{
codeBytes = x64CodeBytes;
}
codePointer = VirtualAlloc(
IntPtr.Zero,
new UIntPtr((uint)codeBytes.Length),
AllocationType.COMMIT | AllocationType.RESERVE,
MemoryProtection.EXECUTE_READWRITE
);
Marshal.Copy(codeBytes, 0, codePointer, codeBytes.Length);
CpuIDDelegate cpuIdDelg = (CpuIDDelegate)Marshal.GetDelegateForFunctionPointer(codePointer, typeof(CpuIDDelegate));
// invoke
GCHandle handle = default(GCHandle);
var buffer = new byte[16];
try
{
handle = GCHandle.Alloc(buffer, GCHandleType.Pinned);
cpuIdDelg(level, buffer);
}
finally
{
if (handle != default(GCHandle))
{
handle.Free();
}
}
return buffer;
}
finally
{
if (codePointer != IntPtr.Zero)
{
VirtualFree(codePointer, 0, 0x8000);
codePointer = IntPtr.Zero;
}
}
}
[UnmanagedFunctionPointerAttribute(CallingConvention.Cdecl)]
private delegate void CpuIDDelegate(int level, byte[] buffer);
[DllImport("kernel32.dll", SetLastError = true)]
private static extern IntPtr VirtualAlloc(IntPtr lpAddress, UIntPtr dwSize, AllocationType flAllocationType,
MemoryProtection flProtect);
[DllImport("kernel32")]
private static extern bool VirtualFree(IntPtr lpAddress, UInt32 dwSize, UInt32 dwFreeType);
[Flags()]
private enum AllocationType : uint
{
COMMIT = 0x1000,
RESERVE = 0x2000,
RESET = 0x80000,
LARGE_PAGES = 0x20000000,
PHYSICAL = 0x400000,
TOP_DOWN = 0x100000,
WRITE_WATCH = 0x200000
}
[Flags()]
private enum MemoryProtection : uint
{
EXECUTE = 0x10,
EXECUTE_READ = 0x20,
EXECUTE_READWRITE = 0x40,
EXECUTE_WRITECOPY = 0x80,
NOACCESS = 0x01,
READONLY = 0x02,
READWRITE = 0x04,
WRITECOPY = 0x08,
GUARD_Modifierflag = 0x100,
NOCACHE_Modifierflag = 0x200,
WRITECOMBINE_Modifierflag = 0x400
}
// Basic ASM strategy --
// void x86CpuId(int level, byte* buffer)
// {
// eax = level
// cpuid
// buffer[0] = eax
// buffer[4] = ebx
// buffer[8] = ecx
// buffer[12] = edx
// }
private readonly static byte[] x86CodeBytes = {
0x55, // push ebp
0x8B, 0xEC, // mov ebp,esp
0x53, // push ebx
0x57, // push edi
0x8B, 0x45, 0x08, // mov eax, dword ptr [ebp+8] (move level into eax)
0x0F, 0xA2, // cpuid
0x8B, 0x7D, 0x0C, // mov edi, dword ptr [ebp+12] (move address of buffer into edi)
0x89, 0x07, // mov dword ptr [edi+0], eax (write eax, ... to buffer)
0x89, 0x5F, 0x04, // mov dword ptr [edi+4], ebx
0x89, 0x4F, 0x08, // mov dword ptr [edi+8], ecx
0x89, 0x57, 0x0C, // mov dword ptr [edi+12],edx
0x5F, // pop edi
0x5B, // pop ebx
0x8B, 0xE5, // mov esp,ebp
0x5D, // pop ebp
0xc3 // ret
};
private readonly static byte[] x64CodeBytes = {
0x53, // push rbx this gets clobbered by cpuid
// rcx is level
// rdx is buffer.
// Need to save buffer elsewhere, cpuid overwrites rdx
// Put buffer in r8, use r8 to reference buffer later.
// Save rdx (buffer addy) to r8
0x49, 0x89, 0xd0, // mov r8, rdx
// Move ecx (level) to eax to call cpuid, call cpuid
0x89, 0xc8, // mov eax, ecx
0x0F, 0xA2, // cpuid
// Write eax et al to buffer
0x41, 0x89, 0x40, 0x00, // mov dword ptr [r8+0], eax
0x41, 0x89, 0x58, 0x04, // mov dword ptr [r8+4], ebx
0x41, 0x89, 0x48, 0x08, // mov dword ptr [r8+8], ecx
0x41, 0x89, 0x50, 0x0c, // mov dword ptr [r8+12], edx
0x5b, // pop rbx
0xc3 // ret
};
}
注意 CPUID0 需要按正确的顺序读取：
//a twelve character ASCII string stored in EBX, EDX, ECX - in that order
var cpuid0s = new string(ASCIIEncoding.ASCII.GetChars(
cpuid0.Skip(4).Take(4).Concat(
cpuid0.Skip(12).Take(4)).Concat(
cpuid0.Skip(8).Take(4)).ToArray()));