LilyPond not working in jail mounted "noexec"

[Marc Reymann]

Hello LilyPond users,

I’ve created a chroot jail for LilyPond 2.18.2 on Ubuntu 12.04.4 LTS which I
installed by executing the binary
lilypond-2.18.2-1.linux-64.sh. I have followed the instructions the
instructions on
http://www.lilypond.org/doc/v2.19/Documentation/usage/command_002dline-usage#lilypond-in-chroot-jail
and it works only if the loopfile is mounted WITHOUT “noexec”.

The lilypond binary will be executed on .ly files of unknown origin and I
cannot use the “-dsafe” option since
it breaks some functionality. Still I try to make rendering as safe as
possible by using the “noexec” mount option
as suggested in the manual here:
http://www.lilypond.org/doc/v2.19/Documentation/usage/command_002dline-usage#basic-command-line-options-for-lilypond


I’ve used a minimal example for testing:

address@hidden:~# cat /mnt/lilyloop/lilyhome/test.ly
\version "2.14.1"
{
  % middle tie looks funny here:
  <c' d'' b''>8. ~ <c' d'' b''>8
}

The user „pigpen“ has sudo rights to execute /usr/local/bin/lilypond


Case 1: Jail mounted WITHOUT “noexec” - /home/lily/loopfile on /mnt/lilyloop
type ext3 (rw,nosuid,nodev)

address@hidden:~$ sudo /usr/local/bin/lilypond
-jlily,lily,/mnt/lilyloop,/lilyhome --png --header=texidoc test.ly
GNU LilyPond 2.18.2
Processing `test.ly'
Parsing...
Interpreting music...
Preprocessing graphical objects...
Finding the ideal number of pages...
(process:3701): GLib-WARNING **: getpwuid_r(): failed due to unknown user id
(1002)

Fitting music on 1 page...
Drawing systems...
Layout output to `test.ps'...
Converting to PNG...
Success: compilation successfully completed


Case 2:  Jail mounted WITH “noexec” - /home/lily/loopfile on /mnt/lilyloop
type ext3 (rw,noexec,nosuid,nodev)

address@hidden:~$ sudo /usr/local/bin/lilypond
-jlily,lily,/mnt/lilyloop,/lilyhome --png --header=texidoc test.ly
GNU LilyPond 2.18.2
Processing `test.ly'
Parsing...
Interpreting music...
Preprocessing graphical objects...
Finding the ideal number of pages...
(process:3783): GLib-WARNING **: getpwuid_r(): failed due to unknown user id
(1002)

(process:3783): Pango-WARNING **:
/usr/local/lilypond/usr/bin/..//lib/pango/1.6.0/modules/pango-basic-fc.so:
failed to map segment from shared object: Operation not permitted

(process:3783): Pango-WARNING **: Failed to load Pango module
'/usr/local/lilypond/usr/bin/..//lib/pango/1.6.0/modules/pango-basic-fc' for
id 'BasicScriptEngineFc'

(process:3783): Pango-WARNING **: failed to choose a font, expect ugly
output. engine-type='PangoRenderFc', script='common'

(process:3783): Pango-CRITICAL **: pango_fc_font_lock_face: assertion
`PANGO_IS_FC_FONT (font)' failed


What am I doing wrong? Is the setup still safe without the “noexec” option?

Thank you all in advance,
Marc