From 732361736810166aeba87616c93206b3e252aabe Mon Sep 17 00:00:00 2001

From: Matt Coleman <matt@datto.com>

Date: Fri, 23 Sep 2022 19:28:25 -0400

Subject: [PATCH] feat(dmsquash-live): add new dmsquash-live-autooverlay module

(cherry picked from commit a3c67d27e75223bb45df19f850d246ced9a09938)

---

 man/dracut.cmdline.7.asc                      |   4 +

 .../create-overlay-genrules.sh                |  10 ++

 .../create-overlay.sh                         | 119 ++++++++++++++++++

 .../module-setup.sh                           |  25 ++++

 pkgbuild/dracut.spec                          |   3 +-

 test/TEST-16-DMSQUASH/create-root.sh          |  12 +-

 test/TEST-16-DMSQUASH/test-init.sh            |   6 +

 test/TEST-16-DMSQUASH/test.sh                 |  38 +++++-

 test/container/Dockerfile-Arch                |   4 +-

 test/container/Dockerfile-Debian              |   1 +

 test/container/Dockerfile-Fedora-latest       |   1 +

 test/container/Dockerfile-OpenSuse-latest     |   2 +-

 12 files changed, 216 insertions(+), 9 deletions(-)

 create mode 100755 modules.d/90dmsquash-live-autooverlay/create-overlay-genrules.sh

 create mode 100755 modules.d/90dmsquash-live-autooverlay/create-overlay.sh

 create mode 100755 modules.d/90dmsquash-live-autooverlay/module-setup.sh

diff --git a/man/dracut.cmdline.7.asc b/man/dracut.cmdline.7.asc

index fda62fd1..40d13d83 100644

--- a/man/dracut.cmdline.7.asc

+++ b/man/dracut.cmdline.7.asc

@@ -1161,6 +1161,10 @@ rd.live.overlay=/dev/sdb1:persistent-overlay.img

 rd.live.overlay=UUID=99440c1f-8daa-41bf-b965-b7240a8996f4

 --

+**rd.live.overlay.cowfs=**__[btrfs|ext4|xfs]__::

+Specifies the filesystem to use when formatting the overlay partition.

+The default is ext4.

+

 **rd.live.overlay.size=**__<size_MiB>__::

 Specifies a non-persistent Device-mapper overlay size in MiB.  The default is

 _32768_.

diff --git a/modules.d/90dmsquash-live-autooverlay/create-overlay-genrules.sh b/modules.d/90dmsquash-live-autooverlay/create-overlay-genrules.sh

new file mode 100755

index 00000000..ed168d9f

--- /dev/null

+++ b/modules.d/90dmsquash-live-autooverlay/create-overlay-genrules.sh

@@ -0,0 +1,10 @@

+#!/bin/sh

+

+# shellcheck disable=SC2154

+case "$root" in

+    live:/dev/*)

+        printf 'SYMLINK=="%s", RUN+="/sbin/initqueue --settled --onetime --unique /sbin/create-overlay %s"\n' \

+            "${root#live:/dev/}" "${root#live:}" >> /etc/udev/rules.d/95-create-overlay.rules

+        wait_for_dev -n "${root#live:}"

+        ;;

+esac

diff --git a/modules.d/90dmsquash-live-autooverlay/create-overlay.sh b/modules.d/90dmsquash-live-autooverlay/create-overlay.sh

new file mode 100755

index 00000000..c89bda2b

--- /dev/null

+++ b/modules.d/90dmsquash-live-autooverlay/create-overlay.sh

@@ -0,0 +1,119 @@

+#!/bin/sh

+

+type getarg > /dev/null 2>&1 || . /lib/dracut-lib.sh

+

+if getargbool 0 rd.live.debug -n -y rdlivedebug; then

+    exec > /tmp/create-overlay.$$.out

+    exec 2>> /tmp/create-overlay.$$.out

+    set -x

+fi

+

+gatherData() {

+    overlay=$(getarg rd.live.overlay)

+    if [ -z "$overlay" ]; then

+        info "Skipping overlay creation: kernel command line parameter 'rd.live.overlay' is not set"

+        exit 0

+    fi

+    # shellcheck disable=SC2086

+    if ! str_starts ${overlay} LABEL=; then

+        die "Overlay creation failed: the partition must be set by LABEL in the 'rd.live.overlay' kernel parameter"

+    fi

+

+    overlayLabel=${overlay#LABEL=}

+    # shellcheck disable=SC2086

+    if [ -b /dev/disk/by-label/${overlayLabel} ]; then

+        info "Skipping overlay creation: overlay already exists"

+        exit 0

+    fi

+

+    filesystem=$(getarg rd.live.overlay.cowfs)

+    [ -z "$filesystem" ] && filesystem="ext4"

+    if [ "$filesystem" != "ext4" ] && [ "$filesystem" != "xfs" ] && [ "$filesystem" != "btrfs" ]; then

+        die "Overlay creation failed: only ext4, xfs, and btrfs are supported in the 'rd.live.overlay.cowfs' kernel parameter"

+    fi

+

+    live_dir=$(getarg rd.live.dir)

+    [ -z "$live_dir" ] && live_dir="LiveOS"

+

+    [ -z "$1" ] && exit 1

+    rootDevice=$1

+

+    # The kernel command line's 'root=' parameter was parsed into the $root variable by the dmsquash-live module.

+    # $root contains the path to a symlink within /dev/disk/by-label, which points to a partition.

+    # This script needs that partition's parent block device.

+    # shellcheck disable=SC2046

+    # shellcheck disable=SC2086

+    rootDeviceAbsolutePath=$(readlink -f ${rootDevice})

+    rootDeviceSysfsPath=/sys/class/block/${rootDeviceAbsolutePath##*/}

+    if [ -f "${rootDeviceSysfsPath}/partition" ]; then

+        # shellcheck disable=SC2086

+        partition=$(cat ${rootDeviceSysfsPath}/partition)

+    else

+        partition=0

+    fi

+    # shellcheck disable=SC2086

+    readonly=$(cat ${rootDeviceSysfsPath}/ro)

+    # shellcheck disable=SC2086

+    if [ "$partition" != "1" ] || [ "$readonly" != "0" ]; then

+        info "Skipping overlay creation: unpartitioned or read-only media detected"

+        exit 0

+    fi

+    # shellcheck disable=SC2046

+    # shellcheck disable=SC2086

+    fullDriveSysfsPath=$(readlink -f ${rootDeviceSysfsPath}/..)

+    blockDevice=/dev/${fullDriveSysfsPath##*/}

+    currentPartitionCount=$(grep --count -E "${blockDevice#/dev/}[0-9]+" /proc/partitions)

+

+    # shellcheck disable=SC2086

+    freeSpaceStart=$(parted --script ${blockDevice} unit % print free \

+        | awk -v x=${currentPartitionCount} '$1 == x {getline; print $1}')

+    if [ -z "$freeSpaceStart" ]; then

+        info "Skipping overlay creation: there is no free space after the last partition"

+        exit 0

+    fi

+    partitionStart=$((${freeSpaceStart%.*} + 1))

+    if [ $partitionStart -eq 100 ]; then

+        info "Skipping overlay creation: there is not enough free space after the last partition"

+        exit 0

+    fi

+

+    overlayPartition=${blockDevice}$((currentPartitionCount + 1))

+

+    label=$(blkid --match-tag LABEL --output value "$rootDevice")

+    uuid=$(blkid --match-tag UUID --output value "$rootDevice")

+    if [ -z "$label" ] || [ -z "$uuid" ]; then

+        die "Overlay creation failed: failed to look up root device label and UUID"

+    fi

+}

+

+createPartition() {

+    # shellcheck disable=SC2086

+    parted --script --align optimal ${blockDevice} mkpart primary ${partitionStart}% 100%

+}

+

+createFilesystem() {

+    # shellcheck disable=SC2086

+    mkfs.${filesystem} -L ${overlayLabel} ${overlayPartition}

+

+    baseDir=/run/initramfs/create-overlayfs

+    mkdir -p ${baseDir}

+    # shellcheck disable=SC2086

+    mount -t auto ${overlayPartition} ${baseDir}

+

+    mkdir -p ${baseDir}/${live_dir}/ovlwork

+    # shellcheck disable=SC2086

+    mkdir ${baseDir}/${live_dir}/overlay-${label}-${uuid}

+

+    umount ${baseDir}

+    rm -r ${baseDir}

+}

+

+main() {

+    gatherData "$1"

+    createPartition

+    udevsettle

+    createFilesystem

+    udevsettle

+}

+

+main "$1"

diff --git a/modules.d/90dmsquash-live-autooverlay/module-setup.sh b/modules.d/90dmsquash-live-autooverlay/module-setup.sh

new file mode 100755

index 00000000..c3712eba

--- /dev/null

+++ b/modules.d/90dmsquash-live-autooverlay/module-setup.sh

@@ -0,0 +1,25 @@

+#!/bin/bash

+

+check() {

+    # including a module dedicated to live environments in a host-only initrd doesn't make sense

+    [[ $hostonly ]] && return 1

+    return 255

+}

+

+depends() {

+    echo dmsquash-live

+    return 0

+}

+

+installkernel() {

+    instmods btrfs ext4 xfs

+}

+

+install() {

+    inst_multiple awk blkid cat grep mkdir mount parted readlink rmdir tr umount

+    inst_multiple -o mkfs.btrfs mkfs.ext4 mkfs.xfs

+    # shellcheck disable=SC2154

+    inst_hook pre-udev 25 "$moddir/create-overlay-genrules.sh"

+    inst_script "$moddir/create-overlay.sh" "/sbin/create-overlay"

+    dracut_need_initqueue

+}

diff --git a/pkgbuild/dracut.spec b/pkgbuild/dracut.spec

index 71b7421c..0f3efda7 100644

--- a/pkgbuild/dracut.spec

+++ b/pkgbuild/dracut.spec

@@ -141,7 +141,7 @@ Requires: %{name} >= %{version}-%{dist_free_release}

 Requires: %{name} = %{version}-%{release}

 %endif

 Requires: %{name}-network = %{version}-%{release}

-Requires: tar gzip coreutils bash device-mapper curl

+Requires: tar gzip coreutils bash device-mapper curl parted

 %if 0%{?fedora}

 Requires: fuse ntfs-3g

 %endif

@@ -464,6 +464,7 @@ echo 'dracut_rescue_image="yes"' > $RPM_BUILD_ROOT%{dracutlibdir}/dracut.conf.d/

 %files live

 %{dracutlibdir}/modules.d/99img-lib

 %{dracutlibdir}/modules.d/90dmsquash-live

+%{dracutlibdir}/modules.d/90dmsquash-live-autooverlay

 %{dracutlibdir}/modules.d/90dmsquash-live-ntfs

 %{dracutlibdir}/modules.d/90livenet

diff --git a/test/TEST-16-DMSQUASH/create-root.sh b/test/TEST-16-DMSQUASH/create-root.sh

index 9bc1aa5d..c11e17e0 100755

--- a/test/TEST-16-DMSQUASH/create-root.sh

+++ b/test/TEST-16-DMSQUASH/create-root.sh

@@ -11,9 +11,17 @@ udevadm control --reload

 set -e

 udevadm settle

-mkfs.ext4 -q -L dracut /dev/disk/by-id/ata-disk_root

+

+# create a single partition using 50% of the capacity of the image file created by test_setup() in test.sh

+sfdisk /dev/disk/by-id/ata-disk_root << EOF

+2048,161792

+EOF

+

+udevadm settle

+

+mkfs.ext4 -q -L dracut /dev/disk/by-id/ata-disk_root-part1

 mkdir -p /root

-mount /dev/disk/by-id/ata-disk_root /root

+mount /dev/disk/by-id/ata-disk_root-part1 /root

 mkdir -p /root/run /root/testdir

 echo "Creating squashfs"

 mksquashfs /source /root/testdir/rootfs.img -quiet

diff --git a/test/TEST-16-DMSQUASH/test-init.sh b/test/TEST-16-DMSQUASH/test-init.sh

index 068e8f38..959fa25f 100755

--- a/test/TEST-16-DMSQUASH/test-init.sh

+++ b/test/TEST-16-DMSQUASH/test-init.sh

@@ -9,6 +9,12 @@ exec > /dev/console 2>&1

 echo "dracut-root-block-success" | dd oflag=direct,dsync of=/dev/disk/by-id/ata-disk_marker

+if grep -qF ' rd.live.overlay=LABEL=persist ' /proc/cmdline; then

+    # Writing to a file in the root filesystem lets test_run() verify that the autooverlay module successfully created

+    # and formatted the overlay partition and that the dmsquash-live module used it when setting up the rootfs overlay.

+    echo "dracut-autooverlay-success" > /overlay-marker

+fi

+

 export TERM=linux

 export PS1='initramfs-test:\w\$ '

 [ -f /etc/mtab ] || ln -sfn /proc/mounts /etc/mtab

diff --git a/test/TEST-16-DMSQUASH/test.sh b/test/TEST-16-DMSQUASH/test.sh

index cf433489..a446b3c9 100755

--- a/test/TEST-16-DMSQUASH/test.sh

+++ b/test/TEST-16-DMSQUASH/test.sh

@@ -5,8 +5,9 @@ TEST_DESCRIPTION="live root on a squash filesystem"

 KVERSION="${KVERSION-$(uname -r)}"

-# Uncomment this to debug failures

-# DEBUGFAIL="rd.shell rd.debug loglevel=7"

+# Uncomment these to debug failures

+#DEBUGFAIL="rd.shell rd.debug rd.live.debug loglevel=7"

+#DEBUGTOOLS="setsid ls cat sfdisk"

 test_run() {

     dd if=/dev/zero of="$TESTDIR"/marker.img bs=1MiB count=1

@@ -23,6 +24,27 @@ test_run() {

         -initrd "$TESTDIR"/initramfs.testing

     grep -U --binary-files=binary -F -m 1 -q dracut-root-block-success -- "$TESTDIR"/marker.img || return 1

+

+    rootPartitions=$(sfdisk -d "$TESTDIR"/root.img | grep -c 'root\.img[0-9]')

+    [ "$rootPartitions" -eq 1 ] || return 1

+

+    "$testdir"/run-qemu \

+        "${disk_args[@]}" \

+        -boot order=d \

+        -append "rd.live.image rd.live.overlay.overlayfs=1 rd.live.overlay=LABEL=persist rd.live.dir=testdir root=LABEL=dracut console=ttyS0,115200n81 quiet selinux=0 rd.info rd.shell=0 panic=1 oops=panic softlockup_panic=1 $DEBUGFAIL" \

+        -initrd "$TESTDIR"/initramfs.testing-autooverlay

+

+    rootPartitions=$(sfdisk -d "$TESTDIR"/root.img | grep -c 'root\.img[0-9]')

+    [ "$rootPartitions" -eq 2 ] || return 1

+

+    (

+        # Ensure that this test works when run with the `V=1` parameter, which runs the script with `set -o pipefail`.

+        set +o pipefail

+

+        # Verify that the string "dracut-autooverlay-success" occurs in the second partition in the image file.

+        dd if="$TESTDIR"/root.img bs=1MiB skip=80 status=none \

+            | grep -U --binary-files=binary -F -m 1 -q dracut-autooverlay-success

+    ) || return 1

 }

 test_setup() {

@@ -49,7 +71,7 @@ test_setup() {

         ln -s dracut-util "${initdir}/usr/bin/dracut-getarg"

         ln -s dracut-util "${initdir}/usr/bin/dracut-getargs"

-        inst_multiple mkdir ln dd stty mount poweroff

+        inst_multiple mkdir ln dd stty mount poweroff grep "$DEBUGTOOLS"

         cp -a -- /etc/ld.so.conf* "$initdir"/etc

         ldconfig -r "$initdir"

@@ -113,6 +135,16 @@ test_setup() {

         --force "$TESTDIR"/initramfs.testing "$KVERSION" || return 1

     ls -sh "$TESTDIR"/initramfs.testing

+

+    "$basedir"/dracut.sh -l -i "$TESTDIR"/overlay / \

+        --modules "dmsquash-live-autooverlay qemu" \

+        --omit "rngd" \

+        --drivers "ext4 sd_mod" \

+        --no-hostonly --no-hostonly-cmdline \

+        --force "$TESTDIR"/initramfs.testing-autooverlay "$KVERSION" || return 1

+

+    ls -sh "$TESTDIR"/initramfs.testing-autooverlay

+

     rm -rf -- "$TESTDIR"/overlay

 }

diff --git a/test/container/Dockerfile-Arch b/test/container/Dockerfile-Arch

index 922b8ede..4112cc5b 100644

--- a/test/container/Dockerfile-Arch

+++ b/test/container/Dockerfile-Arch

@@ -9,10 +9,10 @@ RUN echo 'export DRACUT_NO_XATTR=1 KVERSION=$(cd /lib/modules; ls -1 | tail -1)'

 # Install needed packages for the dracut CI container

 RUN pacman --noconfirm -Sy \

-    linux dash strace dhclient asciidoc cpio pigz \

+    linux dash strace dhclient asciidoc cpio pigz squashfs-tools \

     qemu btrfs-progs mdadm dmraid nfs-utils nfsidmap lvm2 nbd \

     dhcp networkmanager multipath-tools vi tcpdump open-iscsi \

-    git shfmt shellcheck astyle which base-devel && yes | pacman  -Scc

+    git shfmt shellcheck astyle which base-devel glibc parted && yes | pacman -Scc

 RUN useradd -m build

 RUN su build -c 'cd && git clone https://aur.archlinux.org/perl-config-general.git && cd perl-config-general && makepkg -s --noconfirm'

diff --git a/test/container/Dockerfile-Debian b/test/container/Dockerfile-Debian

index b4c1704e..15eb9958 100644

--- a/test/container/Dockerfile-Debian

+++ b/test/container/Dockerfile-Debian

@@ -42,6 +42,7 @@ RUN apt-get update -y -qq && apt-get upgrade -y -qq && DEBIAN_FRONTEND=nonintera

     network-manager \

     nfs-common \

     open-iscsi \

+    parted \

     pigz \

     pkg-config \

     procps \

diff --git a/test/container/Dockerfile-Fedora-latest b/test/container/Dockerfile-Fedora-latest

index 87c749f9..a38a72ef 100644

--- a/test/container/Dockerfile-Fedora-latest

+++ b/test/container/Dockerfile-Fedora-latest

@@ -49,6 +49,7 @@ RUN dnf -y install --setopt=install_weak_deps=False \

     which \

     ShellCheck \

     shfmt \

+    parted \

     && dnf -y update && dnf clean all

 # Set default command

diff --git a/test/container/Dockerfile-OpenSuse-latest b/test/container/Dockerfile-OpenSuse-latest

index 637d50c6..9aaf07b1 100644

--- a/test/container/Dockerfile-OpenSuse-latest

+++ b/test/container/Dockerfile-OpenSuse-latest

@@ -13,7 +13,7 @@ RUN dnf -y install --setopt=install_weak_deps=False \

     strace libkmod-devel gcc bzip2 xz tar wget rpm-build make git bash-completion \

     sudo kernel dhcp-client qemu-kvm /usr/bin/qemu-system-$(uname -m) e2fsprogs \

     tcpdump iproute iputils kbd NetworkManager btrfsprogs tgt dbus-broker \

-    iscsiuio open-iscsi which ShellCheck procps pigz \

+    iscsiuio open-iscsi which ShellCheck procps pigz parted squashfs \

     && dnf -y update && dnf clean all

 RUN shfmt_version=3.2.4; wget "https://github.com/mvdan/sh/releases/download/v${shfmt_version}/shfmt_v${shfmt_version}_linux_amd64" -O /usr/local/bin/shfmt \

-- 

2.36.1