On Tue, 31 Mar 2020 at 21:20, Laszlo Ersek <lersek@xxxxxxxxxx> wrote:
>
> On 03/31/20 09:56, Ard Biesheuvel wrote:
> > On Mon, 30 Mar 2020 at 20:24, Ard Biesheuvel <ardb@xxxxxxxxxx> wrote:
> >>
> >> On Mon, 30 Mar 2020 at 20:12, Michael Kelley <mikelley@xxxxxxxxxxxxx> wrote:
> >>>
> >>> From: Ard Biesheuvel <ardb@xxxxxxxxxx> Sent: Monday, March 30, 2020 12:51 AM
> >>>>
> >>>> On Mon, 30 Mar 2020 at 09:50, Ard Biesheuvel <ardb@xxxxxxxxxx> wrote:
> >>>>>
> >>>>> On Mon, 30 Mar 2020 at 09:47, Leif Lindholm <leif@xxxxxxxxxxxx> wrote:
> >>>>>>
> >>>>>> On Sat, Mar 28, 2020 at 21:58:09 +0100, Ard Biesheuvel wrote:
> >>>>>>> Commit 9f9223778ef3 ("efi/libstub/arm: Make efi_entry() an ordinary
> >>>>>>> PE/COFF entrypoint") did some code refactoring to get rid of the
> >>>>>>> EFI entry point assembler code, and in the process, it got rid of the
> >>>>>>> assignment of image_addr to the value of _text. Instead, it switched
> >>>>>>> to using the image_base field of the efi_loaded_image struct provided
> >>>>>>> by UEFI, which should contain the same value.
> >>>>>>>
> >>>>>>> However, Michael reports that this is not the case: older GRUB builds
> >>>>>>> corrupt this value in some way, and since we can easily switch back to
> >>>>>>> referring to _text to discover this value, let's simply do that.
> >>>>>>
> >>>>>> It is not clear to me how "older GRUB builds" would differ here.
> >>>>>> I think more investigation is needed before making that claim.
> >>>>>> My suspicion is that some (old) version of non-upstream, shim-enabled
> >>>>>> distro-specific build is playing a part.
> >>>>>>
> >>>>>> So, do we have the option for more detailed investigations, or can we
> >>>>>> vague the claim up to say "some GRUB builds seen in the wild, based
> >>>>>> on an upstream 2.02" or suchlike?
> >>>>>>
> >>>>>
> >>>>> I've queued a fix that prints a nastygram if the value deviates from
> >>>>> the expected one. Let's see if this triggers any reports.
> >>>>
> >>>> (/me looks at context)
> >>>>
> >>>> *This* is the fix that prints a nastygram.
> >>>
> >>> FWIW, I pulled the BOOTAA64.EFI and grubaa64.efi files from CentOS 7.6
> >>> and CentOS 8.0 binary packages and tested both in my Hyper-V VM.
> >>> Using strings | grep '2\.' to get version info, the CentOS 7.6 grubaa64.efi
> >>> shows:
> >>>
> >>> User-Agent: GRUB 2.02~beta2
> >>>
> >>> The CentOS 8.0 grubaa64.efi shows:
> >>>
> >>> User-Agent: GRUB 2.03
> >>>
> >>> Both versions produce the FIRMWARE BUG warning when using Ard's
> >>> latest patch. I'll assume the equivalent RHEL versions are the same.
> >>> So we've got official distro releases that show the problem.
> >>>
> >>> As reported earlier, the BOOTAA64.EFI and grubaa64.efi from a
> >>> Debian release (not exactly sure which one) do not produce the
> >>> FIRMWARE BUG warning. The grubaa64.efi reports as 2.04-4.
> >>>
> >>
> >> Thanks a lot Michael, that is really helpful.
> >
> > I could not reproduce the issue with Debian Stretch's
> > 2.02~beta3-5+deb9u2, so it does appear to be RedHat's value add that
> > is to blame here.
> >
> > @Laszlo: TL;DR RedHat's GRUB for arm64 appears to clobber the
> > image_base field of the efi_loaded_image struct passed to the kernel.
> > Could you please recommend a way to report this?
>
> Yes. I seem to recall that you already have an account at
> <https://bugzilla.redhat.com/>. Please log in, then go to the following
> link:
>
> https://bugzilla.redhat.com/enter_bug.cgi?product=Red%20Hat%20Enterprise%20Linux%208
>
> In the "Component" field, please enter "grub2", then fill in Summary /
> Description / etc.
>
> Please be thorough, as if you wanted me to reproduce the issue :)
>
> After filing the bug, please send the BZ link to me (or add me to the
> bug's CC list), so I can ping some RH bootloader folks directly.
>
https://bugzilla.redhat.com/show_bug.cgi?id=1819624
Thanks.
