From 06472685e239c4b2d013710378c34224d2b8586c Mon Sep 17 00:00:00 2001
From: TheApadayo <muel96@gmail.com>
Date: Tue, 21 Feb 2017 14:15:16 -0500
Subject: [PATCH] [Memory] Add non buggy IsBadReadPtr implementation

---
 src/Components/Modules/Console.cpp |  2 +-
 src/Components/Modules/D3D9Ex.cpp  |  2 +-
 src/Steam/Proxy.cpp                | 16 ++++++----------
 src/Utils/Memory.cpp               | 30 ++++++++++++++++++++++++++++++
 src/Utils/Memory.hpp               |  3 +++
 5 files changed, 41 insertions(+), 12 deletions(-)

diff --git a/src/Components/Modules/Console.cpp b/src/Components/Modules/Console.cpp
index 1c63c920..3a8a66f7 100644
--- a/src/Components/Modules/Console.cpp
+++ b/src/Components/Modules/Console.cpp
@@ -26,7 +26,7 @@ namespace Components
 
 	char** Console::GetAutoCompleteFileList(const char *path, const char *extension, Game::FsListBehavior_e behavior, int *numfiles, int allocTrackType)
 	{
-		if (path == reinterpret_cast<char*>(0xBAADF00D) || path == reinterpret_cast<char*>(0xCDCDCDCD) || IsBadReadPtr(path, 1)) return nullptr;
+		if (path == reinterpret_cast<char*>(0xBAADF00D) || path == reinterpret_cast<char*>(0xCDCDCDCD) || ::Utils::Memory::IsBadReadPtr(path)) return nullptr;
 		return Game::FS_GetFileList(path, extension, behavior, numfiles, allocTrackType);
 	}
 
diff --git a/src/Components/Modules/D3D9Ex.cpp b/src/Components/Modules/D3D9Ex.cpp
index bb49ce30..481b582b 100644
--- a/src/Components/Modules/D3D9Ex.cpp
+++ b/src/Components/Modules/D3D9Ex.cpp
@@ -569,7 +569,7 @@ namespace Components
 
 	HRESULT D3D9Ex::D3D9Device::SetPixelShaderConstantF(UINT StartRegister, CONST float* pConstantData, UINT Vector4fCount)
 	{
-		if (IsBadReadPtr(pConstantData, Vector4fCount * 16))
+		if (::Utils::Memory::IsBadReadPtr(pConstantData/*, Vector4fCount * 16*/))
 		{
 			//Logger::Print("Invalid shader constant array!\n");
 			return D3DERR_INVALIDCALL;
diff --git a/src/Steam/Proxy.cpp b/src/Steam/Proxy.cpp
index 58235c78..f2ace795 100644
--- a/src/Steam/Proxy.cpp
+++ b/src/Steam/Proxy.cpp
@@ -42,10 +42,10 @@ namespace Steam
 
 	void* Interface::lookupMethod(std::string method)
 	{
-		if (IsBadReadPtr(this->interfacePtr, 4)) return nullptr;
+		if (::Utils::Memory::IsBadReadPtr(this->interfacePtr)) return nullptr;
 		unsigned char** vftbl = *static_cast<unsigned char***>(this->interfacePtr);
 
-		while (!IsBadReadPtr(vftbl, 4) && !IsBadCodePtr((FARPROC(*vftbl))))
+		while (!::Utils::Memory::IsBadReadPtr(vftbl) && !::Utils::Memory::IsBadCodePtr((FARPROC(*vftbl))))
 		{
 			if(this->getMethodName(*vftbl) == method) return *vftbl;
 			++vftbl;
@@ -57,7 +57,7 @@ namespace Steam
 	size_t Interface::getMethodParamSize(void* method)
 	{
 		unsigned char* methodPtr = static_cast<unsigned char*>(method);
-		for (; !IsBadReadPtr(methodPtr, 3); ++methodPtr)
+		for (; !::Utils::Memory::IsBadReadPtr(methodPtr); ++methodPtr)
 		{
 			if (methodPtr[0] == 0xC2 && methodPtr[2] == 0) // __stdcall return
 			{
@@ -71,12 +71,12 @@ namespace Steam
 
 	std::string Interface::getMethodName(unsigned char* methodPtr)
 	{
-		for(;!IsBadReadPtr(methodPtr, 3); ++methodPtr)
+		for(;!::Utils::Memory::IsBadReadPtr(methodPtr); ++methodPtr)
 		{
 			if(methodPtr[0] == 0x68) // Push
 			{
 				char* name = *reinterpret_cast<char**>(&methodPtr[1]);
-				if(!IsBadReadPtr(name, 1)) return name;
+				if(::Utils::Memory::IsBadReadPtr(name)) return name;
 			}
 			else if(methodPtr[0] == 0xC2 && methodPtr[2] == 0) // __stdcall return
 			{
@@ -322,11 +322,7 @@ namespace Steam
 
 	void Proxy::StartSteamIfNecessary()
 	{
-		if (Proxy::GetSteamDirectory().empty()
-#ifndef DEBUG
-			|| !Steam::Enabled()
-#endif
-			) return;
+		if (Proxy::GetSteamDirectory().empty() || !Steam::Enabled()) return;
 
 		HKEY hRegKey;
 		DWORD pid = 0;
diff --git a/src/Utils/Memory.cpp b/src/Utils/Memory.cpp
index 54192a9b..e3f3ac42 100644
--- a/src/Utils/Memory.cpp
+++ b/src/Utils/Memory.cpp
@@ -64,4 +64,34 @@ namespace Utils
 
 		return true;
 	}
+
+	bool Memory::IsBadReadPtr(const void* ptr)
+	{
+		MEMORY_BASIC_INFORMATION mbi = { 0 };
+		if (::VirtualQuery(ptr, &mbi, sizeof(mbi)))
+		{
+			DWORD mask = (PAGE_READONLY | PAGE_READWRITE | PAGE_WRITECOPY | PAGE_EXECUTE_READ | PAGE_EXECUTE_READWRITE | PAGE_EXECUTE_WRITECOPY);
+			bool b = !(mbi.Protect & mask);
+			// check the page is not a guard page
+			if (mbi.Protect & (PAGE_GUARD | PAGE_NOACCESS)) b = true;
+
+			return b;
+		}
+		return true;
+	}
+
+	bool Memory::IsBadCodePtr(const void* ptr)
+	{
+		MEMORY_BASIC_INFORMATION mbi = { 0 };
+		if (::VirtualQuery(ptr, &mbi, sizeof(mbi)))
+		{
+			DWORD mask = (PAGE_EXECUTE_READ | PAGE_EXECUTE_READWRITE | PAGE_EXECUTE_WRITECOPY);
+			bool b = !(mbi.Protect & mask);
+			// check the page is not a guard page
+			if (mbi.Protect & (PAGE_GUARD | PAGE_NOACCESS)) b = true;
+
+			return b;
+		}
+		return true;
+	}
 }
diff --git a/src/Utils/Memory.hpp b/src/Utils/Memory.hpp
index 74505c18..acd5497d 100644
--- a/src/Utils/Memory.hpp
+++ b/src/Utils/Memory.hpp
@@ -130,5 +130,8 @@ namespace Utils
 		static void FreeAlign(const void* data);
 
 		static bool IsSet(void* mem, char chr, size_t length);
+
+		static bool IsBadReadPtr(const void* ptr);
+		static bool IsBadCodePtr(const void* ptr);
 	};
 }