[debhelper-devel] Bug#887904: dh_installsystemd will unmask services *after* an attempt to start them

[Michael Biebl]

Am 21.01.2018 um 16:28 schrieb Michael Biebl:
> Package: debhelper
> Version: 11.1.3
> Severity: important
> 
> dh_installsystemd masks services on "remove". The background here is, that
> SysV init scripts are conffiles which are only removed on "purge".
> 
> Upon re-installation, this mask is removed again.
> With dh_systemd_enable, this was done before dh_installinit, so the mask
> was gone when invoke-rc.d tried to start the service.
> 
> With compat 11 and dh_installsystemd, the dh_installsystemd helper is
> called after dh_installinit. As a result, invoke-rc.d will try to start
> a service which is still masked.

See the generated postinst script.

The more I think about these ordering issues, the more I'm convinced
that for services which ship both a native service file and a systemd
service file, we should leave the start/stop/restart of the service to
dh_installsystemd/deb-systemd-invoke and only use the  invoke-rc.d call
on sysvinit systems.

I.e. we inverse the current logic:
If dh_installinit detects, that for a given /etc/init.d/network-manager
there exists a /lib/systemd/system/network-manager.service (either as
symlink or real file), it will wrap the invoke-rc.d call

> if [ "$1" = "configure" ] || [ "$1" = "abort-upgrade" ] || [ "$1" = "abort-deconfigure" ] || [ "$1" = "abort-remove" ] ; then
> 	if [ -x "/etc/init.d/network-manager" ]; then
> 		update-rc.d network-manager defaults >/dev/null
> 		if [ -n "$2" ]; then
> 			_dh_action=restart
> 		else
> 			_dh_action=start
> 		fi
>               if ! [ -d /run/systemd/system ]; then
> 		         invoke-rc.d network-manager $_dh_action || exit 1
>               fi
> 	fi
> fi

This would be a change of behaviour, so I'm not sure if this should be
in compat 11 or deferred to compat 12. But afaics, the current
dh_installsystemd in compat 11 is not actually working due to these
ordering issues which are a result of no longer having two separate
helpers which ran befor and after dh_installinit.

-- 
Why is it that all of the instruments seeking intelligent life in the
universe are pointed away from Earth?
-------------- next part --------------
#!/bin/sh

set -e

# This script can be called in the following ways:
#
# After the package was installed:
#	<postinst> configure <old-version>
#
#
# If prerm fails during upgrade or fails on failed upgrade:
#	<old-postinst> abort-upgrade <new-version>
#
# If prerm fails during deconfiguration of a package:
#	<postinst> abort-deconfigure in-favour <new-package> <version>
#	           removing <old-package> <version>
#
# If prerm fails during replacement due to conflict:
#	<postinst> abort-remove in-favour <new-package> <version>

case "$1" in
    configure)
        # Create netdev group. Members of group netdev get access to the PolicyKit action
        # org.freedesktop.NetworkManager.settings.modify.system without prior authentication
        addgroup --quiet --system netdev

        NIF=/etc/network/interfaces
        if [ -z "$2" ] && [ -f $NIF ]; then
            ifaces=`grep -v '^#' $NIF | awk '/iface/ {print $2}' | sort -u | sed -e 's/lo//' -e '/^$/d' -e 's/^/- /'`
            if [ -n "$ifaces" ]; then
                echo "" 1>&2
                echo "The following network interfaces were found in $NIF" 1>&2
                echo "which means they are currently configured by ifupdown:" 1>&2
                echo "$ifaces" 1>&2
                echo "If you want to manage those interfaces with NetworkManager instead" 1>&2
                echo "remove their configuration from $NIF." 1>&2
                echo "" 1>&2
            fi
        fi

        # Fix up existing /etc/resolv.conf symlinks after the migration to /run
        if dpkg --compare-versions "$2" lt-nl "1.8.0-4"; then
            if [ "$(readlink /etc/resolv.conf)" = /var/run/NetworkManager/resolv.conf ] ; then
                ln -sf  /run/NetworkManager/resolv.conf /etc/resolv.conf
            fi
        fi
        ;;

    abort-upgrade|abort-deconfigure|abort-remove)
        ;;

    *)
        echo "$0 called with unknown argument \`$1'" 1>&2
        exit 1
        ;;
esac

# Automatically added by dh_installdeb/11.1.3
dpkg-maintscript-helper rm_conffile /etc/dbus-1/system.d/nm-avahi-autoipd.conf 1.1.90-2\~ -- "$@"
dpkg-maintscript-helper mv_conffile /etc/NetworkManager/dispatcher.d/01ifupdown /etc/NetworkManager/dispatcher.d/01-ifupdown 1.8.0-5\~ -- "$@"
# End automatically added section
# Automatically added by dh_installinit/11.1.3
if [ "$1" = "configure" ] || [ "$1" = "abort-upgrade" ] || [ "$1" = "abort-deconfigure" ] || [ "$1" = "abort-remove" ] ; then
	if [ -x "/etc/init.d/network-manager" ]; then
		update-rc.d network-manager defaults >/dev/null
		if [ -n "$2" ]; then
			_dh_action=restart
		else
			_dh_action=start
		fi
		invoke-rc.d network-manager $_dh_action || exit 1
	fi
fi
# End automatically added section
# Automatically added by dh_installsystemd/11.1.3
if [ "$1" = "configure" ] || [ "$1" = "abort-upgrade" ] || [ "$1" = "abort-deconfigure" ] || [ "$1" = "abort-remove" ] ; then
	# This will only remove masks created by d-s-h on package removal.
	deb-systemd-helper unmask 'NetworkManager.service' >/dev/null || true

	# was-enabled defaults to true, so new installations run enable.
	if deb-systemd-helper --quiet was-enabled 'NetworkManager.service'; then
		# Enables the unit on first installation, creates new
		# symlinks on upgrades if the unit file has changed.
		deb-systemd-helper enable 'NetworkManager.service' >/dev/null || true
	else
		# Update the statefile to add new symlinks (if any), which need to be
		# cleaned up on purge. Also remove old symlinks.
		deb-systemd-helper update-state 'NetworkManager.service' >/dev/null || true
	fi
fi
# End automatically added section
# Automatically added by dh_installsystemd/11.1.3
if [ "$1" = "configure" ] || [ "$1" = "abort-upgrade" ] || [ "$1" = "abort-deconfigure" ] || [ "$1" = "abort-remove" ] ; then
	# This will only remove masks created by d-s-h on package removal.
	deb-systemd-helper unmask 'NetworkManager-dispatcher.service' >/dev/null || true

	# was-enabled defaults to true, so new installations run enable.
	if deb-systemd-helper --quiet was-enabled 'NetworkManager-dispatcher.service'; then
		# Enables the unit on first installation, creates new
		# symlinks on upgrades if the unit file has changed.
		deb-systemd-helper enable 'NetworkManager-dispatcher.service' >/dev/null || true
	else
		# Update the statefile to add new symlinks (if any), which need to be
		# cleaned up on purge. Also remove old symlinks.
		deb-systemd-helper update-state 'NetworkManager-dispatcher.service' >/dev/null || true
	fi
fi
# End automatically added section
# Automatically added by dh_installsystemd/11.1.3
if [ "$1" = "configure" ] || [ "$1" = "abort-upgrade" ] || [ "$1" = "abort-deconfigure" ] || [ "$1" = "abort-remove" ] ; then
	# This will only remove masks created by d-s-h on package removal.
	deb-systemd-helper unmask 'NetworkManager-wait-online.service' >/dev/null || true

	# was-enabled defaults to true, so new installations run enable.
	if deb-systemd-helper --quiet was-enabled 'NetworkManager-wait-online.service'; then
		# Enables the unit on first installation, creates new
		# symlinks on upgrades if the unit file has changed.
		deb-systemd-helper enable 'NetworkManager-wait-online.service' >/dev/null || true
	else
		# Update the statefile to add new symlinks (if any), which need to be
		# cleaned up on purge. Also remove old symlinks.
		deb-systemd-helper update-state 'NetworkManager-wait-online.service' >/dev/null || true
	fi
fi
# End automatically added section


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