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Allow using / as destination in custom mounts.
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Also make this backwards compatible with live-rw labelled volumes.
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Tails developers committed Apr 9, 2012
1 parent 0622a98 commit f92f379
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Showing 2 changed files with 45 additions and 77 deletions.
67 changes: 23 additions & 44 deletions scripts/live
View file
Expand Up @@ -952,7 +952,11 @@ setup_unionfs ()
log_end_msg
fi

mkdir -p /overlay
# tmpfs file systems
touch /etc/fstab
mkdir -p /live
mount -t tmpfs tmpfs /live
mkdir -p /live/overlay

# Looking for persistence devices or files
if [ -n "${PERSISTENCE}" ] && [ -z "${NOPERSISTENCE}" ]
Expand Down Expand Up @@ -999,7 +1003,7 @@ setup_unionfs ()

if echo ${PERSISTENCE_METHOD} | grep -qe "\<overlay\>"
then
overlays="${root_overlay_label} ${old_root_overlay_label} ${old_home_overlay_label} ${custom_overlay_label}"
overlays="${old_root_overlay_label} ${old_home_overlay_label} ${custom_overlay_label}"
fi

if echo ${PERSISTENCE_METHOD} | grep -qe "\<snapshot\>"
Expand All @@ -1009,7 +1013,6 @@ setup_unionfs ()

local root_snapdata=""
local home_snapshot_label=""
local root_overlay_label=""
local overlay_devices=""
for media in $(find_persistence_media "${overlays}" "${snapshots}" "${whitelistdev}")
do
Expand All @@ -1030,16 +1033,14 @@ setup_unionfs ()
home_snapdata="${media#*=}"
fi
;;
${root_overlay_label}=*|${old_root_overlay_label}=*)
if [ -z "${root_overlay_device}" ]
then
device="${media#*=}"
root_overlay_device="${device}"
fi
${old_root_overlay_label}=*)
device="${media#*=}"
fix_backwards_compatibility ${device} / union
overlay_devices="${overlay_devices} ${device}"
;;
${old_home_overlay_label}=*)
device="${media#*=}"
fix_home_rw_compatibility ${device}
fix_backwards_compatibility ${device} /home bind
overlay_devices="${overlay_devices} ${device}"
;;
${custom_overlay_label}=*)
Expand All @@ -1048,26 +1049,6 @@ setup_unionfs ()
;;
esac
done

if [ -b "${root_overlay_device}" ]
then
PERSISTENCE_IS_ON="1"
export PERSISTENCE_IS_ON

cowdevice=${root_overlay_device}
cow_fstype=$(get_fstype "${root_overlay_device}")
if [ -z "${PERSISTENCE_READONLY}" ]
then
cow_mountopt="rw,noatime"
else
cow_mountopt="ro,noatime"
fi

if [ "${FORCEPERSISTENCEFSCK}" = "Yes" ]
then
fsck -y ${cowdevice}
fi
fi
elif [ -n "${NFS_COW}" ] && [ -z "${NOPERSISTENCE}" ]
then
# check if there are any nfs options
Expand Down Expand Up @@ -1104,13 +1085,13 @@ setup_unionfs ()

if [ "${UNIONTYPE}" != "unionmount" ]
then
if [ -n "${PERSISTENCE_READONLY}" ]
if [ -n "${PERSISTENCE_READONLY}" ] && [ "${cowdevice}" != "tmpfs" ]
then
mount -t tmpfs -o rw,noatime,mode=755 tmpfs "/overlay"
root_backing="${rootmnt}/live/persistence/$(basename ${cowdevice})-root"
mount -t tmpfs -o rw,noatime,mode=755 tmpfs "/live/overlay"
root_backing="/live/persistence/$(basename ${cowdevice})-root"
mkdir -p ${root_backing}
else
root_backing="/overlay"
root_backing="/live/overlay"
fi

if [ "${cow_fstype}" = "nfs" ]
Expand Down Expand Up @@ -1164,12 +1145,11 @@ setup_unionfs ()
unionmountopts="-t ${cow_fstype} -o noatime,union,${cow_mountopt} ${cowdevice}"
mount_full $unionmountopts "${unionmountpoint}"
else
cow_dir="/overlay${dir}"
cow_dir="/live/overlay${dir}"
rofs_dir="${rofs}${dir}"
mkdir -p ${cow_dir}
if [ -n "${PERSISTENCE_READONLY}" ] && [ "${cowdevice}" != "tmpfs" ]
then
#mount -t tmpfs -o rw,noatime,mode=755 tmpfs "${cow_dir}"
do_union ${unionmountpoint} ${cow_dir} ${root_backing} ${rofs_dir}
else
do_union ${unionmountpoint} ${cow_dir} ${rofs_dir}
Expand All @@ -1180,11 +1160,6 @@ setup_unionfs ()
# Correct the permissions of /:
chmod 0755 "${rootmnt}"

# tmpfs file systems
touch /etc/fstab
mkdir -p "${rootmnt}/live"
mount -t tmpfs tmpfs ${rootmnt}/live

live_rofs_list=""
# SHOWMOUNTS is necessary for custom mounts with the union option
# Since we may want to do custom mounts in user-space it's best to always enable SHOWMOUNTS
Expand All @@ -1193,7 +1168,7 @@ setup_unionfs ()
# XXX: is the for loop really necessary? rofslist can only contain one item (see above XXX about EXPOSEDROOT) and this is also assumed elsewhere above (see use of $rofs above).
for d in ${rofslist}
do
live_rofs="${rootmnt}/live/rofs/${d##*/}"
live_rofs="/live/rofs/${d##*/}"
live_rofs_list="${live_rofs_list} ${live_rofs}"
mkdir -p "${live_rofs}"
case d in
Expand Down Expand Up @@ -1223,7 +1198,7 @@ setup_unionfs ()
# Gather information about custom mounts from devies detected as overlays
get_custom_mounts ${custom_mounts} ${overlay_devices}

[ -n "${DEBUG}" ] && cp ${custom_mounts} "${rootmnt}/live/persistence"
[ -n "${DEBUG}" ] && cp ${custom_mounts} "/live/persistence"

# Now we do the actual mounting (and symlinking)
local used_overlays=""
Expand All @@ -1245,9 +1220,13 @@ setup_unionfs ()
try_snap "${home_snapdata}" "${rootmnt}" "HOME" "/home"
fi

mkdir -p "${rootmnt}/live"
mount -o move /live "${rootmnt}/live" >/dev/null 2>&1 || mount -o bind /live "${rootmnt}/live" || log_warning_msg "Unable to move or bind /live to ${rootmnt}/live"

# shows cow fs on /overlay for use by live-snapshot
mkdir -p "${rootmnt}/live/overlay"
mount -o move /overlay "${rootmnt}/live/overlay" >/dev/null 2>&1 || mount -o bind /overlay "${rootmnt}/live/overlay" || log_warning_msg "Unable to move or bind /overlay to ${rootmnt}/live/overlay"
mount -o move /live/overlay "${rootmnt}/live/overlay" >/dev/null 2>&1 || mount -o bind /overlay "${rootmnt}/live/overlay" || log_warning_msg "Unable to move or bind /overlay to ${rootmnt}/live/overlay"

}

check_dev ()
Expand Down
55 changes: 22 additions & 33 deletions scripts/live-helpers
View file
Expand Up @@ -15,7 +15,6 @@ else
udevinfo='udevinfo'
fi

root_overlay_label="full-ov"
old_root_overlay_label="live-rw"
old_home_overlay_label="home-rw"
custom_overlay_label="custom-ov"
Expand Down Expand Up @@ -261,7 +260,6 @@ Arguments ()
;;

persistence-subtext=*)
root_overlay_label="${root_overlay_label}-${ARGUMENT#persistence-subtext=}"
old_root_overlay_label="${old_root_overlay_label}-${ARGUMENT#persistence-subtext=}"
old_home_overlay_label="${old_home_overlay_label}-${ARGUMENT#persistence-subtext=}"
custom_overlay_label="${custom_overlay_label}-${ARGUMENT#persistence-subtext=}"
Expand Down Expand Up @@ -745,16 +743,7 @@ try_mount ()
mount_persistence_media ()
{
local device=${1}
local backing=""

# We can't mount into ${rootmnt}/live before ${rootmnt} has been
# mounted since that would cover our mountpoint.
if [ -n "${rootmnt}" ] && [ -z "$(what_is_mounted_on ${rootmnt})" ]
then
backing="/$(basename ${device})-backing"
else
backing="${rootmnt}/live/persistence/$(basename ${device})"
fi
local backing="/live/persistence/$(basename ${device})"

mkdir -p "${backing}"
local old_backing="$(where_is_mounted ${device})"
Expand Down Expand Up @@ -1266,7 +1255,7 @@ do_union ()

get_custom_mounts ()
{
# Side-effect: leaves $devices with live-persistence.conf mounted in ${rootmnt}/live/persistence
# Side-effect: leaves $devices with live-persistence.conf mounted in /live/persistence
# Side-effect: prints info to file $custom_mounts

local custom_mounts=${1}
Expand Down Expand Up @@ -1299,7 +1288,7 @@ get_custom_mounts ()

if [ -n "${DEBUG}" ] && [ -e "${include_list}" ]
then
cp ${include_list} ${rootmnt}/live/persistence/${persistence_list}.${device_name}
cp ${include_list} /live/persistence/${persistence_list}.${device_name}
fi

while read dir options # < ${include_list}
Expand All @@ -1310,9 +1299,9 @@ get_custom_mounts ()
continue
fi

if trim_path ${dir} | grep -q -e "^[^/]" -e "^/$" -e "^/live\(/.*\)\?$" -e "^/\(.*/\)\?\.\.\?\(/.*\)\?$"
if trim_path ${dir} | grep -q -e "^[^/]" -e "^/live\(/.*\)\?$" -e "^/\(.*/\)\?\.\.\?\(/.*\)\?$"
then
log_warning_msg "Skipping unsafe custom mount ${dir}: must be an absolute path containing neither the \".\" nor \"..\" special dirs, and cannot be \"/live\" (or any sub-directory therein) or \"/\" (for the latter, use ${root_overlay_label}-type persistence)"
log_warning_msg "Skipping unsafe custom mount ${dir}: must be an absolute path containing neither the \".\" nor \"..\" special dirs, and cannot be \"/live\" or any sub-directory therein."
continue
fi

Expand Down Expand Up @@ -1416,8 +1405,13 @@ activate_custom_mounts ()

if [ -n "$(what_is_mounted_on "${dest}")" ]
then
log_warning_msg "Skipping custom mount ${dest}: $(what_is_mounted_on "${dest}") is already mounted there"
continue
if [ "${dest}" = "${rootmnt}" ]
then
umount "${dest}"
else
log_warning_msg "Skipping custom mount ${dest}: $(what_is_mounted_on "${dest}") is already mounted there"
continue
fi
fi

if [ ! -d "${dest}" ]
Expand Down Expand Up @@ -1474,7 +1468,7 @@ activate_custom_mounts ()
local rofs_dest_backing=""
if [ -n "${opt_link}"]
then
for d in ${rootmnt}/live/rofs/*
for d in /live/rofs/*
do
if [ -n "${rootmnt}" ]
then
Expand All @@ -1496,23 +1490,16 @@ activate_custom_mounts ()
link_files ${source} ${dest} ${rootmnt}
elif [ -n "${opt_link}" ] && [ -n "${PERSISTENCE_READONLY}" ]
then
mkdir -p ${rootmnt}/live/persistence
local links_source=$(mktemp -d ${rootmnt}/live/persistence/links-source-XXXXXX)
mkdir -p /live/persistence
local links_source=$(mktemp -d /live/persistence/links-source-XXXXXX)
chown_ref ${source} ${links_source}
chmod_ref ${source} ${links_source}
# We put the cow dir in the below strange place to
# make it absolutely certain that the link source
# has its own directory and isn't nested with some
# other custom mount (if so that mount's files would
# be linked, causing breakage.
if [ -n "${rootmnt}" ]
then
local cow_dir="/overlay/live/persistence/$(basename ${links_source})"
else
# This is happens if persistence is activated
# post boot
local cow_dir="/live/overlay/live/persistence/$(basename ${links_source})"
fi
local cow_dir="/live/overlay/live/persistence/$(basename ${links_source})"
mkdir -p ${cow_dir}
chown_ref "${source}" "${cow_dir}"
chmod_ref "${source}" "${cow_dir}"
Expand All @@ -1531,7 +1518,7 @@ activate_custom_mounts ()
# is non-empty (and necessary) only for unions
if [ -n "${rootmnt}" ]
then
local cow_dir="$(echo ${dest} | sed -e "s|^${rootmnt}|/overlay/|")"
local cow_dir="$(echo ${dest} | sed -e "s|^${rootmnt}|/live/overlay/|")"
else
# This is happens if persistence is activated
# post boot
Expand Down Expand Up @@ -1562,9 +1549,11 @@ activate_custom_mounts ()
echo ${used_devices}
}

fix_home_rw_compatibility ()
fix_backwards_compatibility ()
{
local device=${1}
local dir=${2}
local opt=${3}

if [ -n "${PERSISTENCE_READONLY}" ]
then
Expand All @@ -1580,8 +1569,8 @@ fix_home_rw_compatibility ()
local include_list="${backing}/${persistence_list}"
if [ ! -r "${include_list}" ]
then
echo "# home-rw backwards compatibility:
/home source=." > "${include_list}"
echo "# persistence backwards compatibility:
${dir} ${opt},source=." > "${include_list}"
fi
}

Expand Down

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