diff --git a/nixos/doc/manual/release-notes/rl-1903.xml b/nixos/doc/manual/release-notes/rl-1903.xml index cec399b62199..fc3d75f32cf0 100644 --- a/nixos/doc/manual/release-notes/rl-1903.xml +++ b/nixos/doc/manual/release-notes/rl-1903.xml @@ -535,6 +535,20 @@ use nixos-rebuild boot; reboot. + + + Symlinks in /etc (except /etc/static) + are now relative instead of absolute. This makes possible to examine + NixOS container's /etc directory from host system + (previously it pointed to host /etc when viewed from host, + and to container /etc when viewed from container chroot). + + + This also makes /etc/os-release adhere to + the standard + for NixOS containers. + + Flat volumes are now disabled by default in hardware.pulseaudio. diff --git a/nixos/modules/system/etc/make-etc.sh b/nixos/modules/system/etc/make-etc.sh index 1ca4c3046f0e..9c0520e92fc2 100644 --- a/nixos/modules/system/etc/make-etc.sh +++ b/nixos/modules/system/etc/make-etc.sh @@ -10,6 +10,11 @@ users_=($users) groups_=($groups) set +f +# Create relative symlinks, so that the links can be followed if +# the NixOS installation is not mounted as filesystem root. +# Absolute symlinks violate the os-release format +# at https://www.freedesktop.org/software/systemd/man/os-release.html +# and break e.g. systemd-nspawn and os-prober. for ((i = 0; i < ${#targets_[@]}; i++)); do source="${sources_[$i]}" target="${targets_[$i]}" @@ -19,14 +24,14 @@ for ((i = 0; i < ${#targets_[@]}; i++)); do # If the source name contains '*', perform globbing. mkdir -p $out/etc/$target for fn in $source; do - ln -s "$fn" $out/etc/$target/ + ln -s --relative "$fn" $out/etc/$target/ done else - + mkdir -p $out/etc/$(dirname $target) if ! [ -e $out/etc/$target ]; then - ln -s $source $out/etc/$target + ln -s --relative $source $out/etc/$target else echo "duplicate entry $target -> $source" if test "$(readlink $out/etc/$target)" != "$source"; then @@ -34,13 +39,13 @@ for ((i = 0; i < ${#targets_[@]}; i++)); do exit 1 fi fi - + if test "${modes_[$i]}" != symlink; then echo "${modes_[$i]}" > $out/etc/$target.mode echo "${users_[$i]}" > $out/etc/$target.uid echo "${groups_[$i]}" > $out/etc/$target.gid fi - + fi done diff --git a/nixos/modules/system/etc/setup-etc.pl b/nixos/modules/system/etc/setup-etc.pl index eed20065087f..82ef49a2a27e 100644 --- a/nixos/modules/system/etc/setup-etc.pl +++ b/nixos/modules/system/etc/setup-etc.pl @@ -4,6 +4,7 @@ use File::Copy; use File::Path; use File::Basename; use File::Slurp; +use File::Spec; my $etc = $ARGV[0] or die; my $static = "/etc/static"; @@ -17,6 +18,20 @@ sub atomicSymlink { return 1; } +# Create relative symlinks, so that the links can be followed if +# the NixOS installation is not mounted as filesystem root. +# Absolute symlinks violate the os-release format +# at https://www.freedesktop.org/software/systemd/man/os-release.html +# and break e.g. systemd-nspawn and os-prober. +sub atomicRelativeSymlink { + my ($source, $target) = @_; + my $tmp = "$target.tmp"; + unlink $tmp; + my $rel = File::Spec->abs2rel($source, dirname $target); + symlink $rel, $tmp or return 0; + rename $tmp, $target or return 0; + return 1; +} # Atomically update /etc/static to point at the etc files of the # current configuration. @@ -103,7 +118,7 @@ sub link { if (-e "$_.mode") { my $mode = read_file("$_.mode"); chomp $mode; if ($mode eq "direct-symlink") { - atomicSymlink readlink("$static/$fn"), $target or warn; + atomicRelativeSymlink readlink("$static/$fn"), $target or warn; } else { my $uid = read_file("$_.uid"); chomp $uid; my $gid = read_file("$_.gid"); chomp $gid; @@ -117,7 +132,7 @@ sub link { push @copied, $fn; print CLEAN "$fn\n"; } elsif (-l "$_") { - atomicSymlink "$static/$fn", $target or warn; + atomicRelativeSymlink "$static/$fn", $target or warn; } }