** Tags removed: verification-needed-focal
** Tags added: verification-done-focal

-- 
You received this bug notification because you are a member of Kernel
Packages, which is subscribed to linux in Ubuntu.
https://bugs.launchpad.net/bugs/1996071

Title:
  [UBUNTU 20.04] boot: Add s390x secure boot trailer

Status in Ubuntu on IBM z Systems:
  Fix Released
Status in linux package in Ubuntu:
  Invalid
Status in linux source package in Focal:
  Fix Released
Status in linux source package in Jammy:
  Fix Released
Status in linux source package in Kinetic:
  Fix Released

Bug description:
  SRU Justification:
  ==================

  [Impact]

   * Secure boot of Linux on s390x will no longer be possible
     with an upcoming IBM zSystems firmware update.

  [Fix]

   * aa127a069ef3 aa127a069ef312aca02b730d5137e1778d0c3ba7 "s390/boot: add 
secure boot trailer"
     for kinetic and jammy

   * 
https://launchpadlibrarian.net/633020900/0001-s390-boot-add-secure-boot-trailer.patch
     backport for focal

  [Test Plan]

   * An IBM z15 or LinuxONE III LPAR with zFCP/SCSI disk storage is
  required.

   * Ensure that 'Enable Secure Boot for Linux' is marked in case
     'SCSI Load' is selected at the HMCs Load task and Activation Profile.

   * Perform an Ubuntu Server installation, either 20.04 or 22.04
     (latest ISO).
     It will be a secure boot installation by default in case
     'Enable Secure Boot for Linux' was marked.

   * Check sysfs:
     /sys/firmware/ipl/has_secure
        '1' indicates hw support for secure boot, otherwise '0'
     /sys/firmware/ipl/secure
        '1' indicates that secure IPL was successful, otherwise '0'

   * Navigate to the HMC task 'System information'
     and check the active firmware release.

   * Ensure that Ubuntu is still bootable in secure-boot mode
     with the updated firmware active,
     by for example doing a reboot after the firmware upgrade.

   * There is also a way to test the trailer on systems that do not
     have the updated firmware yet - in this case use the following script:
     https://launchpadlibrarian.net/633126861/check_sb_trailer.sh

  [Where problems could occur]

   * The 'trailer' might be broken, invalid or in a wrong format
     and can't be identified or read properly,
     or may cause issues while compressing/decompressing the kernel.

   * In worst case secure boot might become broken,
     even on systems that are still on the unpatched firmware level.

   * Or secure boot will become broken in general.

  [Other Info]

   * The above commit was upstream accepted with v6.1-rc3.

   * And it got tagged for upstream stable with:
     "Cc: <sta...@vger.kernel.org> # 5.2+"

   * But since this bug is marked as critical, and the patch is relatively
     short, traceable and s390x-specific, I'll go ahead and submit this
     patch for Jammy and Focal ahead of upstream stable.

   * Since on focal file 'vmlinux.lds.S' is at a different location
     'arch/s390/boot/compressed/' instead of 'arch/s390/boot/'
     and the context is slightly different, the backport is needed.

   * It's planned to have kernel 6.2 in lunar (23.04), hence it will have
     the patch incl. when at the planned target level.

  __________

  Description:   boot: Add secure boot trailer
  Symptom:       Secure boot of Linux will no longer be possible with an 
upcoming
                 IBM Z firmware update.

  Problem:       New IBM Z firmware requires signed bootable images to contain a
                 trailing data block with a specific format.

  Solution:      Add the trailing data block to the Linux kernel image.

  Reproduction:  Apply latest firmware, perform IPL with Secure Boot
  enabled.

  Fix:           available upstream with
  Upstream-ID:   aa127a069ef312aca02b730d5137e1778d0c3ba7

  Preventive:    yes

  Date:          2022-10-27
  Author:        Peter Oberparleiter <ober...@linux.ibm.com>
  Component:     kernel

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu-z-systems/+bug/1996071/+subscriptions


-- 
Mailing list: https://launchpad.net/~kernel-packages
Post to     : kernel-packages@lists.launchpad.net
Unsubscribe : https://launchpad.net/~kernel-packages
More help   : https://help.launchpad.net/ListHelp

Reply via email to