diff --git a/fedora-common-ostree.yaml b/fedora-common-ostree.yaml index e174ac6..66ae591 100644 --- a/fedora-common-ostree.yaml +++ b/fedora-common-ostree.yaml @@ -110,3 +110,111 @@ postprocess: ln -srf /usr/bin/true ${x} fi done + - | + #!/usr/bin/env bash + set -xeuo pipefail + + # Setup unit & script for readonly sysroot migration: + # - https://fedoraproject.org/wiki/Changes/Silverblue_Kinoite_readonly_sysroot + # - https://bugzilla.redhat.com/show_bug.cgi?id=2060976 + + cat > /usr/lib/systemd/system/fedora-silverblue-readonly-sysroot.service <"EOF" +[Unit] +Description=Fedora Silverblue Read-Only Sysroot Migration +Documentation=https://fedoraproject.org/wiki/Changes/Silverblue_Kinoite_readonly_sysroot +ConditionPathExists=!/var/lib/.fedora_silverblue_readonly_sysroot +RequiresMountsFor=/sysroot /boot +ConditionPathIsReadWrite=/sysroot + +[Service] +Type=oneshot +ExecStart=/usr/libexec/fedora-silverblue-readonly-sysroot +RemainAfterExit=yes + +[Install] +WantedBy=multi-user.target +"EOF" + chmod 644 /usr/lib/systemd/system/fedora-silverblue-readonly-sysroot.service + + cat > /usr/libexec/fedora-silverblue-readonly-sysroot <"EOF" +#!/bin/bash + +# Update an existing system to use a read only sysroot +# See https://fedoraproject.org/wiki/Changes/Silverblue_Kinoite_readonly_sysroot +# and https://bugzilla.redhat.com/show_bug.cgi?id=2060976 + +set -euo pipefail + +main() { + # Used to condition execution of this unit at the systemd level + local -r stamp_file="/var/lib/.fedora_silverblue_readonly_sysroot + + if [[ -f "${stamp_file}" ]]; then + exit 0 + fi + + local -r ostree_sysroot_readonly="$(ostree config --repo=/sysroot/ostree/repo get "sysroot.readonly" &> /dev/null || echo "false")" + if [[ "${ostree_sysroot_readonly}" == "true" ]]; then + # Nothing to do + touch "${stamp_file}" + exit 0 + fi + + local -r boot_entries="$(ls -A /boot/loader/entries/ | wc -l)" + + # Ensure that we can read BLS entries to avoid touching systems where /boot + # is not mounted + if [[ "${boot_entries}" -eq 0 ]]; then + echo "No BLS entry found: Maybe /boot is not mounted?" 1>&2 + echo "This is unexpected thus no migration will be performed" 1>&2 + touch "${stamp_file}" + exit 0 + fi + + # Check if any existing deployment is still missing the rw karg + local rw_kargs_found=0 + local count=0 + for f in "/boot/loader/entries/"*; do + count="$(grep -c "^options .* rw" "${f}" || true)" + if [[ "${count}" -ge 1 ]]; then + rw_kargs_found=$((rw_kargs_found + 1)) + fi + done + + # Some deployments are still missing the rw karg. Let's try to update them + if [[ "${boot_entries}" -ne "${rw_kargs_found}" ]]; then + ostree admin kargs edit-in-place --append-if-missing=rw || \ + echo "Failed to edit kargs in place with ostree" 1>&2 + fi + + # Re-check if any existing deployment is still missing the rw karg + rw_kargs_found=0 + count=0 + for f in "/boot/loader/entries/"*; do + count="$(grep -c "^options .* rw" "${f}" || true)" + if [[ "${count}" -ge 1 ]]; then + rw_kargs_found=$((rw_kargs_found + 1)) + fi + done + unset count + + # If all deployments are good, then we can set the sysroot.readonly option + # in the ostree repo config + if [[ "${boot_entries}" -eq "${rw_kargs_found}" ]]; then + echo "Setting up the sysroot.readonly option in the ostree repo config" + ostree config --repo=/sysroot/ostree/repo set "sysroot.readonly" "true" + touch "${stamp_file}" + exit 0 + fi + + # If anything else before failed, we will retry on next boot + echo "Will retry next boot" 1>&2 + exit 0 +} + +main "${@}" +EOF + chmod 755 /usr/libexec/fedora-silverblue-readonly-sysroot + + # Enable the corresponding unit + systemctl enable fedora-silverblue-readonly-sysroot.service