[MERGE #5214 @MikeHolman] remove unnecessary validation when connecting to JIT process

Merge pull request #5214 from MikeHolman:partialcopy

We connect to JIT process before script runs, so we don't need to validate that the modules passed are valid (and this validation code was insufficient anyway).

This fixes issue where on rare occasion ReadProcessMemory was returning STATUS_PARTIAL_COPY and causing validation to fail. Apparently ReadProcessMemory hitting a page fault can cause this, which seems like the most probable cause.

OS: 11823544

Author: MikeHolman

lib/JITServer/JITServer.cpp

@@ -119,85 +119,6 @@ __RPC_USER PSCRIPTCONTEXT_HANDLE_rundown(__RPC__in PSCRIPTCONTEXT_HANDLE phConte
     ServerCleanupScriptContext(nullptr, &phContext);
 }
 
-HRESULT CheckModuleAddress(HANDLE process, LPCVOID remoteImageBase, LPCVOID localImageBase)
-{
-    byte remoteImageHeader[0x1000];
-    MEMORY_BASIC_INFORMATION remoteImageInfo;
-    SIZE_T resultBytes = VirtualQueryEx(process, (LPCVOID)remoteImageBase, &remoteImageInfo, sizeof(remoteImageInfo));
-    if (resultBytes != sizeof(remoteImageInfo))
-    {
-        Assert(UNREACHED);
-        return E_ACCESSDENIED;
-    }
-    if (remoteImageInfo.BaseAddress != (PVOID)remoteImageBase)
-    {
-        Assert(UNREACHED);
-        return E_ACCESSDENIED;
-    }
-    if (remoteImageInfo.Type != MEM_IMAGE)
-    {
-        Assert(UNREACHED);
-        return E_ACCESSDENIED;
-    }
-    if (remoteImageInfo.State != MEM_COMMIT)
-    {
-        Assert(UNREACHED);
-        return E_ACCESSDENIED;
-    }
-
-    if (remoteImageInfo.RegionSize < sizeof(remoteImageHeader))
-    {
-        Assert(UNREACHED);
-        return E_ACCESSDENIED;
-    }
-
-    if (!ReadProcessMemory(process, remoteImageBase, remoteImageHeader, sizeof(remoteImageHeader), &resultBytes))
-    {
-        return HRESULT_FROM_WIN32(GetLastError());
-    }
-    if (resultBytes < sizeof(remoteImageHeader))
-    {
-        Assert(UNREACHED);
-        return E_ACCESSDENIED;
-    }
-    PIMAGE_DOS_HEADER localDosHeader = (PIMAGE_DOS_HEADER)localImageBase;
-    PIMAGE_NT_HEADERS localNtHeader = (PIMAGE_NT_HEADERS)((BYTE*)localDosHeader + localDosHeader->e_lfanew);
-
-    PIMAGE_DOS_HEADER remoteDosHeader = (PIMAGE_DOS_HEADER)remoteImageHeader;
-    PIMAGE_NT_HEADERS remoteNtHeader = (PIMAGE_NT_HEADERS)((BYTE*)remoteDosHeader + remoteDosHeader->e_lfanew);
-
-    uintptr_t remoteHeaderMax = (uintptr_t)remoteImageHeader + sizeof(remoteImageHeader);
-    uintptr_t remoteMaxRead = (uintptr_t)remoteNtHeader + sizeof(IMAGE_NT_HEADERS);
-    if (remoteMaxRead >= remoteHeaderMax || remoteMaxRead < (uintptr_t)remoteImageHeader)
-    {
-        Assert(UNREACHED);
-        return E_ACCESSDENIED;
-    }
-
-    if (localNtHeader->FileHeader.NumberOfSections != remoteNtHeader->FileHeader.NumberOfSections)
-    {
-        Assert(UNREACHED);
-        return E_ACCESSDENIED;
-    }
-    if (localNtHeader->FileHeader.NumberOfSymbols != remoteNtHeader->FileHeader.NumberOfSymbols)
-    {
-        Assert(UNREACHED);
-        return E_ACCESSDENIED;
-    }
-    if (localNtHeader->OptionalHeader.CheckSum != remoteNtHeader->OptionalHeader.CheckSum)
-    {
-        Assert(UNREACHED);
-        return E_ACCESSDENIED;
-    }
-    if (localNtHeader->OptionalHeader.SizeOfImage != remoteNtHeader->OptionalHeader.SizeOfImage)
-    {
-        Assert(UNREACHED);
-        return E_ACCESSDENIED;
-    }
-
-    return S_OK;
-}
-
 HRESULT
 ServerConnectProcess(
     handle_t binding,
@@ -229,16 +150,6 @@ ServerConnectProcess(
         return E_ACCESSDENIED;
     }
 #endif
-    hr = CheckModuleAddress(targetHandle, (LPCVOID)chakraBaseAddress, (LPCVOID)AutoSystemInfo::Data.dllLoadAddress);
-    if (FAILED(hr))
-    {
-        return hr;
-    }
-    hr = CheckModuleAddress(targetHandle, (LPCVOID)crtBaseAddress, (LPCVOID)AutoSystemInfo::Data.GetCRTHandle());
-    if (FAILED(hr))
-    {
-        return hr;
-    }
     return ProcessContextManager::RegisterNewProcess(clientPid, targetHandle, chakraBaseAddress, crtBaseAddress);
 }