Comment by thom_nic

I was curious, and since the author of this answer provided links to what they called leaks [1], it's not difficult to download both the leak and ReactOS source [2] and look for similarities. So, out of curiosity, that's what I did.

I started poking at some source files at random in ntoskernel, and it only took a minute to get some "hits" from the ReactOS source:

    $ rg InitializeContextThread
    ./ntoskrnl/ke/thrdobj.c:872:        KiInitializeContextThread(Thread,
    ./ntoskrnl/ke/powerpc/thrdini.c:53:KiInitializeContextThread(IN PKTHREAD Thread,
    ./ntoskrnl/ke/i386/thrdini.c:92:KiInitializeContextThread(IN PKTHREAD Thread,
    ./ntoskrnl/ke/amd64/thrdini.c:36:KiInitializeContextThread(IN PKTHREAD Thread,
    ./ntoskrnl/ke/arm/thrdini.c:53:KiInitializeContextThread(IN PKTHREAD Thread,
    ./ntoskrnl/include/internal/ke.h:464:KiInitializeContextThread(

    $ rg NpxFrame
    ./ntoskrnl/ke/i386/v86vdm.c:473:    PFX_SAVE_AREA NpxFrame;
    ./ntoskrnl/ke/i386/v86vdm.c:480:    NpxFrame = &StackFrame->NpxArea;
    ./ntoskrnl/ke/i386/v86vdm.c:481:    ASSERT((ULONG_PTR)NpxFrame % 16 == 0);
    ./ntoskrnl/ke/i386/v86vdm.c:485:    RtlCopyMemory(KiGetThreadNpxArea(Thread), NpxFrame, sizeof(FX_SAVE_AREA));
    ./ntoskrnl/ke/i386/v86vdm.c:510:    PFX_SAVE_AREA NpxFrame = &StackFrame->NpxArea;
    ./ntoskrnl/ke/i386/v86vdm.c:512:    ASSERT((ULONG_PTR)NpxFrame % 16 == 0);
    ./ntoskrnl/ke/i386/v86vdm.c:551:    RtlCopyMemory(NpxFrame, V86Frame->ThreadStack, sizeof(FX_SAVE_AREA));

Now that said, I have no idea what I'm looking for, or if this is significant. But since we have the source for both, it seems we can do better than speculate w/r/t how much code is similar between them. I know that does not prove copying but I think the author's point can't be blindly dismissed.

[1] https://github.com/Zer0Mem0ry/ntoskrnl

[2] https://sourceforge.net/projects/reactos/files/ReactOS/