fs_mgr: overlayfs unit test

#! /bin/bash

#

# adb remount tests (overlayfs focus)

#

# Conditions:

#  - Must be a userdebug build.

#  - Must be in adb mode.

#  - Kernel must have overlayfs enabled and patched to support override_creds.

#  - Must have either squashfs, ext4-dedupe or right-sized partitions.

#  - Minimum expectation system and vender are overlayfs covered partitions.

#

# Helper Variables

SPACE=" "

# A _real_ embedded tab character

TAB="`echo | tr '\n' '\t'`"

# A _real_ embedded escape character

ESCAPE="`echo | tr '\n' '\033'`"

GREEN="${ESCAPE}[38;5;40m"

RED="${ESCAPE}[38;5;196m"

ORANGE="${ESCAPE}[38;5;255:165:0m"

NORMAL="${ESCAPE}[0m"

# Helper functions

[ "USAGE: inFastboot

Returns: true if device is in fastboot mode" ]

inFastboot() {

  fastboot devices | grep "^${ANDROID_SERIAL}[${SPACE}${TAB}]" > /dev/null

}

[ "USAGE: inAdb

Returns: true if device is in adb mode" ]

inAdb() {

  adb devices | grep -v 'List of devices attached' | grep "^${ANDROID_SERIAL}[${SPACE}${TAB}]" > /dev/null

}

[ "USAGE: adb_sh <commands>

Returns: true if the command succeeded" ]

adb_sh() {

  adb shell "${@}"

}

[ "USAGE: get_property <prop>

Returns the property value" ]

get_property() {

  adb_sh getprop ${1} 2>&1 </dev/null

}

[ "USAGE: isDebuggable

Returns: true if device is (likely) a debug build" ]

isDebuggable() {

  if inAdb && [ 1 -ne `get_property ro.debuggable` ]; then

    false

  fi

}

[ "USAGE: adb_su <commands>

Returns: true if the command running as root succeeded" ]

adb_su() {

  adb_sh su root "${@}"

}

[ "USAGE: adb_cat <file> >stdout

Returns: content of file to stdout with carriage returns skipped,

         true of the file exists" ]

adb_cat() {

    OUTPUT="`adb_sh cat ${1} </dev/null 2>&1`"

    retval=${?}

    echo "${OUTPUT}" | tr -d '\r'

    return ${retval}

}

[ "USAGE: adb_reboot

Returns: true if the reboot command succeeded" ]

adb_reboot() {

  adb reboot remount-test

}

[ "USAGE: adb_wait

Returns: waits until the device has returned" ]

adb_wait() {

  adb wait-for-device

}

[ "USAGE: adb_root

Returns: true if device in root state" ]

adb_root() {

  adb root >/dev/null </dev/null 2>&1 &&

  sleep 1 &&

  adb_wait &&

  sleep 1

}

die() {

  echo "${RED}[  FAILED  ]${NORMAL} ${@}" >&2

  exit 1

}

[ "USAGE: EXPECT_EQ <lval> <rval> [message]

Returns true if (regex) lval matches rval" ]

EXPECT_EQ() {

  lval="${1}"

  rval="${2}"

  shift 2

  if ! ( echo X"${rval}" | grep '^X'"${lval}"'$' >/dev/null 2>/dev/null ); then

    if [ `echo ${lval}${rval}${*} | wc -c` -gt 50 -o "${rval}" != "${rval%

*}" ]; then

      echo "ERROR: expected \"${lval}\"" >&2

      echo "       got \"${rval}\"" |

        sed ': again

             N

             s/\(\n\)\([^ ]\)/\1             \2/

             t again' >&2

      if [ -n "${*}" ] ; then

        echo "       ${*}" >&2

      fi

    else

      echo "ERROR: expected \"${lval}\" got \"${rval}\" ${*}" >&2

    fi

    return 1

  fi

  if [ -n "${*}" ] ; then

    if [ X"${lval}" != X"${rval}" ]; then

      if [ `echo ${lval}${rval}${*} | wc -c` -gt 60 -o "${rval}" != "${rval% *}" ]; then

        echo "INFO: ok \"${lval}\"" >&2

        echo "       = \"${rval}\"" |

          sed ': again

               N

               s/\(\n\)\([^ ]\)/\1          \2/

               t again' >&2

        if [ -n "${*}" ] ; then

          echo "      ${*}" >&2

        fi

      else

        echo "INFO: ok \"${lval}\" = \"${rval}\" ${*}" >&2

      fi

    else

      echo "INFO: ok \"${lval}\" ${*}" >&2

    fi

  fi

  return 0

}

[ "USAGE: check_eq <lval> <rval> [message]

Exits if (regex) lval mismatches rval" ]

check_eq() {

  left="${1}"

  right="${2}"

  shift 2

  EXPECT_EQ "${left}" "${right}" ||

    die "${@}"

}

[ "USAGE: skip_administrative_mounts

Filters out all administrative (eg: sysfs) mounts" ]

skip_administrative_mounts() {

  grep -v -e "^\(overlay\|tmpfs\|none\|sysfs\|proc\|selinuxfs\|debugfs\|bpf\|cg2_bpf\|pstore\|tracefs\|adb\|mtp\|ptp\|devpts\|/data/media\) " -e " /\(cache\|mnt/scratch\|mnt/vendor/persist\|metadata\|data\) "

}

if [ X"-s" = X"${1}" -a -n "${2}" ]; then

  export ANDROID_SERIAL="${2}"

  shift 2

fi

inFastboot && die "device in fastboot mode"

inAdb || die "device not in adb mode"

isDebuggable || die "device not a debug build"

# Do something

adb_wait || die "wait for device failed"

adb_sh ls -d /sys/module/overlay </dev/null || die "overlay module not present"

adb_su ls /sys/module/overlay/parameters/override_creds </dev/null ||

  die "overlay module can not be used on ANDROID"

adb_root &&

  adb_wait &&

  D=`adb disable-verity 2>&1` ||

    die "setup for overlay"

echo "${D}"

if [ X"${D}" != X"${D##*using overlayfs}" ]; then

  echo "${GREEN}[       OK ]${NORMAL} using overlayfs" >&2

fi

if adb_sh ls -d /data/overlay </dev/null >/dev/null 2>&1; then

  echo "/data/overlay setup, clearing out" >&2

  adb_sh rm -rf /data/overlay </dev/null ||

    die "/data/overlay removal"

fi

adb_sh ls -d /cache/overlay </dev/null >/dev/null 2>&1 ||

  adb_sh ls -d /mnt/scratch/overlay </dev/null >/dev/null 2>&1 ||

  die "overlay directory setup"

adb_reboot &&

  adb_wait &&

  adb_sh df -k </dev/null | head -1 &&

  adb_sh df -k </dev/null | grep "^overlay " &&

  adb_sh df -k </dev/null | grep "^overlay .* /system\$" >/dev/null ||

  echo "${ORANGE}[  WARNING ]${NORMAL} overlay takeover before remount not complete" >&2

adb_root &&

  adb_wait &&

  adb remount &&

  adb_sh df -k </dev/null | head -1 &&

  adb_sh df -k </dev/null | grep "^overlay " &&

  adb_sh df -k </dev/null | grep "^overlay .* /system\$" >/dev/null ||

  die  "overlay takeover after remount"

!(adb_sh grep "^overlay " /proc/mounts </dev/null | grep " overlay ro,") &&

  !(adb_sh grep " rw," /proc/mounts </dev/null |

  skip_administrative_mounts) ||

    die "remount overlayfs missed a spot"

adb_su "sed -n '1,/overlay \\/system/p' /proc/mounts" </dev/null |

  skip_administrative_mounts |

  grep -v ' \(squashfs\|ext4\|f2fs\) ' &&

  echo "${ORANGE}[  WARNING ]${NORMAL} overlay takeover after first stage init" >&2 ||

  echo "${GREEN}[       OK ]${NORMAL} overlay takeover in first stage init" >&2

# Check something

A="Hello World! $(date)"

echo "${A}" | adb_sh "cat - > /system/hello"

echo "${A}" | adb_sh "cat - > /vendor/hello"

B="`adb_cat /system/hello`" ||

  die "sytem hello"

check_eq "${A}" "${B}" system before reboot

B="`adb_cat /vendor/hello`" ||

  die "vendor hello"

check_eq "${A}" "${B}" vendor before reboot

adb_reboot &&

  adb_wait &&

  B="`adb_cat /system/hello`" ||

  die "re-read system hello after reboot"

check_eq "${A}" "${B}" system after reboot

# Only root can read vendor if sepolicy permissions are as expected

B="`adb_cat /vendor/hello`" &&

  die "re-read vendor hello after reboot w/o root"

check_eq "cat: /vendor/hello: Permission denied" "${B}" vendor after reboot w/o root

adb_root &&

  adb_wait &&

  B="`adb_cat /vendor/hello`" ||

  die "re-read vendor hello after reboot"

check_eq "${A}" "${B}" vendor after reboot

adb remount &&

  adb_sh rm /system/hello /vendor/hello </dev/null ||

  die "cleanup hello"

B="`adb_cat /system/hello`" &&

  die "re-read system hello after rm"

check_eq "cat: /system/hello: No such file or directory" "${B}" after flash rm

B="`adb_cat /vendor/hello`" &&

  die "re-read vendor hello after rm"

check_eq "cat: /vendor/hello: No such file or directory" "${B}" after flash rm

echo "${GREEN}[  PASSED  ]${NORMAL} adb remount" >&2