Re: Severe bug in grub-2.12-for-windows

[Dave Pickens]

    Hi Glenn,
      
      Some additional info that may give a clue about this issue.
      
      I have attached two additional files:
      
      output.genefi32.txt    output of grub-mkimage for EFI 32 bit
      i386-efi
      
      output.genbios.txt     output of grub-mkimage for non EFI  i386-pc
      
      I noted that the __stack_chk_guard output entries are quite
      different in the working EFI 32 bit versus the failing EFI 64 bit
      output.
      
      In the non EFI output, the __stack_chk_guard entries do not appear
      at all. I expect this is normal.
      
      Many thanks,
      
      Dave

On 12/31/2023 10:18 PM, Glenn Washburn wrote:

> On Sun, 31 Dec 2023 13:10:47 -0500
> Dave Pickens <drummer@pobox.com> wrote:
>
> > Hi,
> >
> > I am the author of Grub2Win.
> >
> > In order to generate kernels from a Windows environment, I rely heavily on the Windows version (grub-2.12-for-windows)
> >
> > In testing, I have discovered that the EFI 64 bit kernel generated by the grub-mkimage.exe module will not boot.
> > The EFI 32 bit and non EFI i386-pc kernels work well and boot with no problem.
> >
> > I have submitted bug report #65072 with details, a screenshot and the script used to generate the kernels.
> > The text of the bug report is shown below.
> >
> > Any help from you would be greatly appreciated as I would like to include the 2.12 kernels in my software soon.
> >
> > Many thanks,
> >
> > Dave Pickens
> >
> >
> > **********************************************************************************************
> >
> >
> > I am testing the newly released version 2.12.
> >
> > Using grub-mkimage.exe to create a bootable 64 bit EFI kernel.
> >
> > When the kernel is loaded at boot time it gives message
> >
> > symbol '_stack_chk_guard' not found
> >       
> I see in your output that grub-mkimage.exe is relocating the symbol
> "_stack_chk_guard", but I'm not sure why. GRUB uses a similarly named
> symbol that has two underscores in front, not one. So I'm guessing that
> something is eating the first underscore, probably in some name
> mangling that only happens on Windows. I see that there are other
> double underscore symbols that showup with one underscore. I wonder if
> this has to do with the compiler used to build the kernel.img.
>
> Daniel how is that executable built? Compiling on Windows or cross
> compiling? What compiler is used?
>
> I don't develop on Windows so I don't know how much more help I'll be
> here.
>
> > See the attached screenshot.
> > Then the kernel aborts.
> >
> > I was extremely careful when generating the kernel to ensure that the matching libraries were used by the grub-mkimage command.
> > The libraries and command are all in the same directory, so it is very unlikely that a mismatch occurred.
> >
> > This bug renders grub-2.12-for-windows useless.
> > The kernel will not boot.
> >
> > I have also attached the Windows .bat script I used to generate the kernels.
> >
> > Note: The 32 bit i386-efi and non EFI i386-pc kernels work fine.
> > The problem is strictly with the 64 bit x86_64-efi kernel.
> >       
> This I find surprising.
>
> Glenn
>
>