Package: pbuilder
Version: 0.231
Severity: wishlist
X-Debbugs-Cc: [email protected]
Dear Maintainer,
I hope this message finds you well. I am writing to address a feature
enhancement for the current pbuilder (version 0.231). As you are aware,
pbuilder already supports the ability to bind-mount directories into the chroot
environment via the `--bindmounts` command-line option (as documented in
pbuilder.8) and the configuration item `BINDMOUNTS` in `pbuilderrc.5`. This
functionality is generally sufficient for our applications, allowing us to
simulate build environments effectively.
However, there are scenarios where we require more control over the
bind-mounting process. Specifically, there are instances when we need to mount
external file systems/folders into the chroot without the expectation that they
can be written to or edited. For example, it might be necessary to bind-mount
an external database or repository for read-only access during the build
process.
With this in mind, I would like to propose the implementation of a read-only
bind-mount option, both as a command-line flag and a configuration item. This
would provide the additional control needed for cases where write access should
be strictly prohibited.
I have prepared a patch that introduces this functionality. My preliminary
testing with `pbuilder build *.dsc` and `pbuilder login (chroot)` suggests that
it operates as expected for my use cases. I suppose this enhancement will be
beneficial to the community, allowing for more secure and predictable build
environments.
I would greatly appreciate your consideration of this request. If you find the
patch satisfactory or if there are any concerns or suggestions for improvement,
please let me know. Thank you for your time and attention to this matter.
Thanks,
Best regards,
Xiangyu LIU
# ---------------------------------------- patch
--------------------------------------------------
diff -Narup a/bash_completion.d/pbuilder b/bash_completion.d/pbuilder
--- a/bash_completion.d/pbuilder 2020-02-16 00:49:39.000000000 +0800
+++ b/bash_completion.d/pbuilder 2024-06-24 12:52:01.013999672 +0800
@@ -57,7 +57,7 @@ _pbuilder()
--buildresult --aptcache --removepackages --extrapackages
--configfile
--hookdir --debemail --debbuildopts --logfile --pkgname-logfile
--aptconfdir --timeout --override-config --binary-arch
--binary-indep
- --preserve-buildplace --bindmounts --debug --twice
--autocleanaptcache
+ --preserve-buildplace --bindmounts --bindmountsro --debug
--twice --autocleanaptcache
--compressprog --debootstrapopts --save-after-login
--save-after-exec
--debootstrap' \
-- "$cur" ) )
diff -Narup a/examples/lvmpbuilder/lib/lvmbuilder-checkparams
b/examples/lvmpbuilder/lib/lvmbuilder-checkparams
--- a/examples/lvmpbuilder/lib/lvmbuilder-checkparams 2018-11-23
18:51:49.000000000 +0800
+++ b/examples/lvmpbuilder/lib/lvmbuilder-checkparams 2024-06-24
12:52:01.013999672 +0800
@@ -88,6 +88,11 @@ while [ -n "$1" ]; do
warn_option $1;
shift; shift;
;;
+ --bindmountsro)
+ BINDMOUNTSRO="${BINDMOUNTSRO} $2"
+ warn_option $1;
+ shift; shift;
+ ;;
--save-after-login|--save-after-exec)
SAVE_AFTER_LOGIN=yes;
warn_option $1;
diff -Narup a/pbuilder.8 b/pbuilder.8
--- a/pbuilder.8 2019-03-15 22:24:28.000000000 +0800
+++ b/pbuilder.8 2024-06-24 12:53:43.223999282 +0800
@@ -535,6 +535,14 @@ specified in a space-delimited manner, s
.B """/srv /somedir /someotherdir"""
.TP
+.BI "\-\-bindmountsro " "bind-mount-points"
+Bind-mount the specified directories to inside the chroot (read-only mode).
+.I "bind-mount-points"
+is a space-delimited list of directories to bind-mount (in read-only mode)
which should be
+specified in a space-delimited manner, surrounded in double quotations, like:
+.B """/srv /somedir /someotherdir"""
+
+.TP
.BI "\-\-debootstrapopts " "\-\-variant=buildd" " " "\-\-keyring" " "
"/usr/share/keyrings/debian\-archive\-keyring.gpg"
Add extra command-line options to debootstrap.
diff -Narup a/pbuilder-checkparams b/pbuilder-checkparams
--- a/pbuilder-checkparams 2019-03-23 21:16:18.000000000 +0800
+++ b/pbuilder-checkparams 2024-06-24 12:52:01.013999672 +0800
@@ -273,6 +273,10 @@ while [ -n "$1" ]; do
BINDMOUNTS="${BINDMOUNTS} $2"
shift; shift;
;;
+ --bindmountsro)
+ BINDMOUNTSRO="${BINDMOUNTSRO} $2"
+ shift; shift;
+ ;;
--debootstrapopts)
# specify this option to set --variant=buildd value to debootstrap
DEBOOTSTRAPOPTS[${#DEBOOTSTRAPOPTS[@]}]="$2";
@@ -452,6 +456,8 @@ fi
# sort BINDMOUNTS to ensure that deeper directories are mounted last
BINDMOUNTS="$(for i in $BINDMOUNTS; do echo $i; done | sort -u)"
+# sort BINDMOUNTSRO to ensure that deeper directories are mounted last
+BINDMOUNTSRO="$(for i in $BINDMOUNTSRO; do echo $i; done | sort -u)"
if [ "$ALLOWUNTRUSTED" = "yes" ]; then
PBUILDERSATISFYDEPENDSOPT[${#PBUILDERSATISFYDEPENDSOPT[@]}]='--allow-untrusted'
diff -Narup a/pbuilder-modules b/pbuilder-modules
--- a/pbuilder-modules 2020-01-18 23:28:49.000000000 +0800
+++ b/pbuilder-modules 2024-06-24 12:52:01.013999672 +0800
@@ -78,6 +78,7 @@ pbuilder main options:
--binary-arch
--preserve-buildplace
--bindmounts [bind-mount-point]
+ --bindmountsro [bind-mount-point in read-only mode]
--debug
--debootstrapopts [debootstrap options]
--save-after-login/--save-after-exec
@@ -281,6 +282,9 @@ function umountproc () {
for mnt in $BINDMOUNTS; do
reversed="$mnt $reversed"
done
+ for mnt in $BINDMOUNTSRO; do
+ reversed="$mnt $reversed"
+ done
for mnt in $reversed; do
umount_one "${mnt#*:}"
done
@@ -472,6 +476,7 @@ function mountproc () {
mount -t firmlink /servers "$BUILDPLACE/servers" || true
mounted[${#mounted[@]}]="$BUILDPLACE/servers"
fi
+ # Normal mount
MOUNTPARAMS="-obind"
[ "$DEB_BUILD_ARCH_OS" = "linux" ] && MOUNTPARAMS="${MOUNTPARAMS}
--make-private"
[ "$DEB_BUILD_ARCH_OS" = "kfreebsd" ] && MOUNTPARAMS="-t nullfs"
@@ -479,6 +484,40 @@ function mountproc () {
mntpoint=${mnt#*:}
mnt=${mnt%%:*}
if [ "$mnt" = "$mntpoint" ]; then
+ log.i "Mounting $mnt"
+ else
+ log.i "Mounting $mnt to $mntpoint"
+ fi
+ if [ -d "$mnt" ]; then
+ create_mntpoint_cmd="mkdir -p"
+ else
+ create_mntpoint_cmd="touch"
+ fi
+ if $create_mntpoint_cmd "$BUILDPLACE/$mntpoint" &&
+ mount $MOUNTPARAMS "$mnt" "$BUILDPLACE/$mntpoint"; then
+ # successful.
+ mounted[${#mounted[@]}]="$BUILDPLACE/$mnt"
+ else
+ # this part of code is the only part which is supposed to fail.
+ # When unsuccessful, backtrack / umount and abort.
+ if [ -n "${mounted[*]}" ]; then
+ log.i "error recovery: umount successfully mounted
mount-points: ${mounted[@]}"
+ for umnt in "${mounted[@]}"; do
+ log.i "umounting $umnt"
+ umount "$umnt"
+ done
+ fi
+ exit 1
+ fi
+ done
+ # Normal mount in read-only mode
+ MOUNTPARAMS="-o bind,ro"
+ [ "$DEB_BUILD_ARCH_OS" = "linux" ] && MOUNTPARAMS="${MOUNTPARAMS}
--make-private"
+ [ "$DEB_BUILD_ARCH_OS" = "kfreebsd" ] && MOUNTPARAMS="-t nullfs"
+ for mnt in $BINDMOUNTSRO; do
+ mntpoint=${mnt#*:}
+ mnt=${mnt%%:*}
+ if [ "$mnt" = "$mntpoint" ]; then
log.i "Mounting $mnt"
else
log.i "Mounting $mnt to $mntpoint"
diff -Narup a/pbuilderrc b/pbuilderrc
--- a/pbuilderrc 2020-12-08 22:55:39.000000000 +0800
+++ b/pbuilderrc 2024-06-24 12:52:01.013999672 +0800
@@ -115,6 +115,10 @@ BUILDUSERNAME=pbuilder
# inside the chroot.
BINDMOUNTS=""
+# BINDMOUNTSRO is a space separated list of things to mount (in read-only mode)
+# inside the chroot.
+BINDMOUNTSRO=""
+
# Set the debootstrap variant to 'buildd' type.
DEBOOTSTRAPOPTS=(
'--variant=buildd'
diff -Narup a/pbuilderrc.5 b/pbuilderrc.5
--- a/pbuilderrc.5 2020-12-08 22:55:48.000000000 +0800
+++ b/pbuilderrc.5 2024-06-24 12:52:01.013999672 +0800
@@ -81,6 +81,20 @@ An Example:
BINDMOUNTS="/home /mnt/test /home/joe/repo:/var/repo"
.EE
.TP
+.BI "BINDMOUNTSRO=" "directories-to-bind-mount[:internal-mountpoint]"
+When this value is set, pbuilder will mount these directories using
+bind-mount, but make them read-only. Different directories are space separated,
+a column can optionally specify a mount destination inside the chroot.
+.br
+Do not bind-mount
+.BR "/" .
+.br
+An Example:
+
+.EX
+BINDMOUNTSRO="/home /mnt/test /home/joe/repo:/var/repo"
+.EE
+.TP
.BI "BUILDDIR=" "/build"
The directory inside the chroot where the build happens.
This directory will contain the build products; the source packages will be
-- System Information:
Debian Release: 12.6
APT prefers stable-updates
APT policy: (500, 'stable-updates'), (500, 'stable-security'), (500,
'proposed-updates'), (500, 'testing'), (500, 'stable')
Architecture: amd64 (x86_64)
Kernel: Linux 6.6.35-02.custom.lfsdefaulthuge-sign (SMP w/8 CPU threads)
Kernel taint flags: TAINT_PROPRIETARY_MODULE, TAINT_OOT_MODULE
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8), LANGUAGE not set
Shell: /bin/sh linked to /usr/bin/dash
Init: systemd (via /run/systemd/system)
LSM: AppArmor: enabled
Versions of packages pbuilder depends on:
ii debconf [debconf-2.0] 1.5.82
ii dpkg-dev 1.21.22
Versions of packages pbuilder recommends:
pn debootstrap | cdebootstrap <none>
pn devscripts <none>
ii eatmydata 130-2
pn fakeroot <none>
ii iproute2 6.1.0-3
ii sudo 1.9.13p3-1+deb12u1
Versions of packages pbuilder suggests:
pn cowdancer <none>
pn gdebi-core <none>
-- debconf information excluded
