[Bug 1959618] Re: shim's fallback hangs in CopyMem, can't boot ISOs

[Steve Langasek]

This appears to be a valid bug report against shim based on the
described problematic behavior of the upstream binary.  However,
fbx64.efi should not be included on ISO images; there is also a bug in
the mastering of this (non-Ubuntu) ISO image.  fbx64.efi is intended to
be installed only on fixed disks as part of a *fallback* boot path in
the event that the boot variables have been wiped from the firmware's
nvram.  It should not be installed on removable media.

** Changed in: shim (Ubuntu)
   Importance: Undecided => Low

** Changed in: shim (Ubuntu)
       Status: New => Triaged

-- 
You received this bug notification because you are a member of Ubuntu
Foundations Bugs, which is subscribed to shim in Ubuntu.
https://bugs.launchpad.net/bugs/1959618

Title:
  shim's fallback hangs in CopyMem, can't boot ISOs

Status in shim package in Ubuntu:
  Triaged

Bug description:
  I'm getting black screen trying to boot KDE Neon Unstable neon-unstable-20220130-0332.iso, which uses
  shim-signed	1.40.7+15.4-0ubuntu9

  This is due to a bug in shim 15.4 fallback (fbx64.efi), it fails on
  CopyMem inside add_to_boot_list on my Lenovo X220 in this place of
  fallback.c:

      CopyMem(newbootorder + 1, bootorder, sizeof (CHAR16) * option);
      CopyMem(newbootorder + option + 1, bootorder + option + 1,
          sizeof (CHAR16) * (nbootorder - option - 1));

  The fix already present in upstream:
  https://github.com/rhboot/shim/commit/41319e14c9144063605750baccd5bb332a3cf4fc

  Kindly asking to apply this patch or update shim to current git
  master.

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/shim/+bug/1959618/+subscriptions