RE: [PATCH 1/1] fix on-first-boot for systemd >= 247

["Moessbauer, Felix" <felix.moessbauer@siemens.com>]

> -----Original Message-----
> From: Schild, Henning (T CED SES-DE) <henning.schild@siemens.com>
> Sent: Friday, July 22, 2022 9:34 AM
> To: Moessbauer, Felix (T CED SES-DE) <felix.moessbauer@siemens.com>
> Cc: isar-users@googlegroups.com; Schmidl, Tobias (SI EP MF GWA EA 4)
> <tobias.schmidl@siemens.com>; Kiszka, Jan (T CED) <jan.kiszka@siemens.com>
> Subject: Re: [PATCH 1/1] fix on-first-boot for systemd >= 247
> 
> Am Fri, 22 Jul 2022 00:04:04 +0200
> schrieb Felix Moessbauer <felix.moessbauer@siemens.com>:
> 
> > This patch fixes the bug that /etc/machine-id is never generated when
> > running from within an initrd with an ro rootfs.
> >
> > In this case, the magic value "uninitialized" has to be used instead
> > of deleting the file.
> >
> > Signed-off-by: Felix Moessbauer <felix.moessbauer@siemens.com>
> > ---
> >  meta/classes/image-postproc-extension.bbclass | 9 ++++++++-
> >  1 file changed, 8 insertions(+), 1 deletion(-)
> >
> > diff --git a/meta/classes/image-postproc-extension.bbclass
> > b/meta/classes/image-postproc-extension.bbclass index
> > 0c412c0d..98c697b2 100644 ---
> > a/meta/classes/image-postproc-extension.bbclass +++
> > b/meta/classes/image-postproc-extension.bbclass @@ -56,8 +56,15 @@
> > image_postprocess_mark() { ROOTFS_POSTPROCESS_COMMAND =+
> > "image_postprocess_machine_id" image_postprocess_machine_id() {
> >      # systemd(1) takes care of recreating the machine-id on first
> > boot
> > +    # for systemd < v247, remove the file, else set to uninitialized
> > +    # (required if initramfs with ro root is used)
> > +    SYSTEMD_VERSION=$( sudo chroot ${IMAGE_ROOTFS} dpkg-query
> > --showformat='${source:Upstream-Version}' --show systemd )
> > +    if dpkg --compare-versions "$SYSTEMD_VERSION" "lt" "247"; then
> > +        sudo rm -f '${IMAGE_ROOTFS}/etc/machine-id'
> > +    else
> > +        echo "uninitialized" | sudo tee
> > '${IMAGE_ROOTFS}/etc/machine-id'
> > +    fi
> >      sudo rm -f '${IMAGE_ROOTFS}/var/lib/dbus/machine-id'
> > -    sudo rm -f '${IMAGE_ROOTFS}/etc/machine-id'
> 
> I would keep the rm and follow up with a conditional write. Also i found that
> /etc/machine-id seems to be 444 at least at the end of the day. If it already is at
> that point, the tee might fail. And it might be that we need to 444 it when we
> create it.

I thought about that as well, but to keep the access rights (which are not 444 initially), I decided to not remove the file.

Felix

> 
> Henning
> 
> >  }
> >
> >  ROOTFS_POSTPROCESS_COMMAND =+
> "image_postprocess_sshd_key_regen"