Erasing dll entry point and PE header

[nefarearworm]

Hi! I an not good at programming, just learning how it works and trying modify ur code. I want to find another way to erase dll entry point and PE header. I implemented it like this in "WinMain":

NtWriteVirtualMemory(ProcessHandle, TargetBase, ZeroBuffer, 4096, nullptr);
NtWriteVirtualMemory(ProcessHandle, (BYTE*)TargetBase + ImageOptionalHeader->AddressOfEntryPoint, ZeroBuffer, 32, nullptr);

Is this a correct way?

Also I discovered that I can erase PE header like this in the end of Loader function:

MappingData->DllEntryFunction(MappingData->TargetBase, DLL_PROCESS_ATTACH, nullptr);

MappingData->ModuleHandle = reinterpret_cast<HINSTANCE>(MappingData->TargetBase);

int i = 1024;

unsigned char* ptr = (unsigned char*)MappingData->TargetBase;

while (i-- > 0)         //working
{
	*ptr++ = 0;
}

while (ImageOptionalHeader->SizeOfHeaders-- > 0)        //also working
{
	*ptr++ = 0;
}

unsigned char* ptr = (unsigned char*)MappingData->TargetBase;

int i = ImageOptionalHeader->SizeOfHeaders;
	
while (i-- > 0)                //dont work
{
		*ptr++ = 0;
}

Its just memset implemention. By bruteforce method I found "1024" which erases all page and target working correctly. But sadly I cant understand how its working. When I pass "4096" my target crashes. The same situation with entry point erasing with the same memset method. Do u see the problem?

Then I made this to erase address of entry point:

//TargetBase is PVOID
	register unsigned char* ptr1 = (unsigned char*)(BYTE*)MappingData->TargetBase + ImageOptionalHeader->AddressOfEntryPoint;

	int SizeOfAddressOfEntryPoint = 32;

	while (SizeOfAddressOfEntryPoint-- > 0)
	{
		*ptr1++ = 0;
	}

Program not crushes but how can I check that entry point was erased?

Another question is how to calculate number of bytes to erase in address of dll entry point? Why its "32" size? Unfortunately I not found any information about this.

I will be gratefull for any answer! Thank you!