[arch-projects] [devtools] [PATCH 2/2] makechrootpkg: build as same UID as invoker

[Dave Reisner]

Changing UID to that of 'nobody' is arbitrary at best, and an
information leak at worst. Let's just drop back to the same UID of the
invoker.
---
 makechrootpkg.in | 20 +++++++++++---------
 1 file changed, 11 insertions(+), 9 deletions(-)

diff --git a/makechrootpkg.in b/makechrootpkg.in
index 8bc18a4..9bb0bfa 100644
--- a/makechrootpkg.in
+++ b/makechrootpkg.in
@@ -234,7 +234,9 @@ prepare_chroot() {
                echo 'SRCDEST="/srcdest"' >> "$copydir/etc/makepkg.conf"
        fi
 
-       chown -R nobody 
"$copydir"/{build,pkgdest,srcpkgdest,logdest,srcdest,startdir}
+       builduser_uid=${SUDO_UID:-$UID}
+       useradd -R "$copydir" -g users -u "$builduser_uid" -s /bin/nologin 
builduser
+       chown -R "$builduser_uid" 
"$copydir"/{build,pkgdest,srcpkgdest,logdest,srcdest,startdir}
 
        if [[ -n $MAKEFLAGS ]]; then
                sed -i '/^MAKEFLAGS=/d' "$copydir/etc/makepkg.conf"
@@ -246,12 +248,12 @@ prepare_chroot() {
                echo "PACKAGER='${PACKAGER}'" >> "$copydir/etc/makepkg.conf"
        fi
 
-       if [[ ! -f $copydir/etc/sudoers.d/nobody-pacman ]]; then
-               cat > "$copydir/etc/sudoers.d/nobody-pacman" <<EOF
+       if [[ ! -f $copydir/etc/sudoers.d/builduser-pacman ]]; then
+               cat > "$copydir/etc/sudoers.d/builduser-pacman" <<EOF
 Defaults env_keep += "HOME"
-nobody ALL = NOPASSWD: /usr/bin/pacman
+builduser ALL = NOPASSWD: /usr/bin/pacman
 EOF
-               chmod 440 "$copydir/etc/sudoers.d/nobody-pacman"
+               chmod 440 "$copydir/etc/sudoers.d/builduser-pacman"
        fi
 
        # This is a little gross, but this way the script is recreated every 
time in the
@@ -302,7 +304,7 @@ _chrootbuild() {
                        for vcsdir in */.$vcs; do
                                rm "${vcsdir%/.$vcs}"
                                cp -a "${dir}_host/${vcsdir%/.$vcs}" .
-                               chown -R nobody "${vcsdir%/.$vcs}"
+                               chown -R builduser "${vcsdir%/.$vcs}"
                        done
                done
        done
@@ -312,7 +314,7 @@ _chrootbuild() {
        # XXX: Keep PKGBUILD writable for pkgver()
        rm PKGBUILD*
        cp /startdir_host/PKGBUILD* .
-       chown nobody PKGBUILD*
+       chown builduser PKGBUILD*
 
        # Safety check
        if [[ ! -w PKGBUILD ]]; then
@@ -320,13 +322,13 @@ _chrootbuild() {
                exit 1
        fi
 
-       sudo -u nobody makepkg $makepkg_args || exit 1
+       sudo -u builduser makepkg $makepkg_args || exit 1
 
        if $run_namcap; then
                pacman -S --needed --noconfirm namcap
                for pkgfile in /startdir/PKGBUILD /pkgdest/*; do
                        echo "Checking ${pkgfile##*/}"
-                       sudo -u nobody namcap "$pkgfile" 2>&1 | tee 
"/logdest/${pkgfile##*/}-namcap.log"
+                       sudo -u builduser namcap "$pkgfile" 2>&1 | tee 
"/logdest/${pkgfile##*/}-namcap.log"
                done
        fi
 
-- 
2.1.0