systemd-247 provides a mechanism called LoadCredential for secrets and
it is better than environment file. See the section of Environment=
in the manual of systemd.exec for more information.
Some options in config.yaml need values to be strings, which currently
can be used with environmentFile but not loadCredential. But it's
possible to use loadCredential for those options, e.g. we can
substitute their values in ExecStart, but not in ExecStartPre due to
[1].
[1]: https://github.com/systemd/systemd/issues/19604
Prior to this patch:
$ nix-instantiate --eval -E '
> with import ./. {
> localSystem.config = "aarch64-unknown-linux-musl";
> };
> (nixos {}).config.nixpkgs.localSystem.config
> '
"aarch64-unknown-linux-gnu"
Because only the system triple was being passed through, the Musl part
of the system specification was lost. This patch fixes various
occurrences of NixOS evaluation when a Nixpkgs evaluation is already
available, to pass through the full elaborated system attribute set,
to avoid this loss of precision.
Since, 4ddc78818e systemd-boot-builder
is broken in two ways:
* if no systemd-boot is currently installed *and* the NIXOS_INSTALL_BOOTLOADER
env variable is not set, it will try to run "bootctl update", which will fail
* if the currently installed systemd-boot version is newer than the version
we're about to install, it will also try to run "bootctl update", which will fail
This patch changes the behaviour,
* for the first case to still fail, but not even bother to try running
"bootctl update" and instead erroring out with an exception
* for the second case to leave the newer version in place, restoring
the pre - 4ddc78818e behaviour
To do the proper version check a new "should_update" helper function was introduced,
mimicing the compare_product C function from bootctl. If the following systemd
issue gets resolved, we would have a nice way to get rid of this function:
> https://github.com/systemd/systemd/issues/23450
This change allows to again switch to a different NixOS configuration which contains
an older systemd-boot.
Co-authored-by: Martin Weinelt <mweinelt@users.noreply.github.com>
`extra-utils` composes the set of programs and libraries needed by
1. copying over all programs
2. copying over all libraries any program directly links against
3. set the runtime path for every program to the library directory
It seems that this approach misses the case where a library itself links
against another library. That is to say, `extra-utils` assumes that
either only progams link against libraries or that every library linked
to by a library is already linked to by a program.
`mount.zfs` linking against `libcrypto`, in turn linking against `libdl`
shows how the current approach falls short:
```
$ objdump -p $(which mount.zfs) | grep NEEDED | grep -e libdl -e libcrypto
NEEDED libcrypto.so.1.1
$ ldd (which mount.zfs) | grep libdl
libdl.so.2 => /nix/store/ybkkrhdwdj227kr20vk8qnzqnmj7a06x-glibc-2.34-115/lib/libdl.so.2 (0x00007f9967a9a000
```
Using `mount.zfs` directly in stage 1 init still works since
`LD_LIBRARY_PATH` overrides this (as intended).
util-linux's `mount` however executes `mount.zfs` with LD_LIBRARY_PATH
removed from its environment as can be seen with strace(1) in an
interactive stage 1 init shell (`boot.shell_on_fail` kernel parameter):
```
# env -i LD_LIBRARY_PATH=$LD_LIBRARY_PATH $(which strace) -ff -e trace=/exec -v -qqq $(which mount) /mnt-root
execve("/nix/store/3gqbb3swgiy749fxd5a4k6kirkr2jr9n-extra-utils/bin/mount", ["/nix/store/3gqbb3swgiy749fxd5a4k"..., "/mnt-root"], ["LD_LIBRARY_PATH=/nix/store/3gqbb"...]) = 0
[pid 1026] execve("/sbin/mount.zfs", ["/sbin/mount.zfs", "<redacted>", "/mnt-root", "-o", "rw,zfsutil"], []) = 0
/sbin/mount.zfs: error while loading shared libraries: libdl.so.2: cannot open shared object file: No such file or directory
--- SIGCHLD {si_signo=SIGCHLD, si_code=CLD_EXITED, si_pid=1026, si_uid=0, si_status=127, si_utime=0, si_stime=0} ---
```
env(1) is used for clarity (hence subshells for absoloute paths).
While `mount` uses the right library path, `mount.zfs` is stripped of
it, so ld.so(8) fails resolve `libdl` (as required by `libcrypto`).
To fix this and not rely on `LD_LIBRARY_PATH` to be set, fix the library
path inside libraries as well.
This finally mounts all ZFS filesystems using `zfsutil` with correct and
intended mount options.
At least pkgs/os-specific/linux/util-linux/default.nix uses
```
"--enable-fs-paths-default=/run/wrappers/bin:/run/current-system/sw/bin:/sbin"
```
which does not cover stage 1 init's PATH as all executables are put
under /bin/.
Fix util-linux's `mount` usage by symlinking /sbin to it.
Consider ZFS filesystems meant to be mounted with zfs.mount(8), e.g.
```
config.fileSystems."/media".options = [ "zfsutil" ];
config.fileSystems."/nix".options = [ "zfsutil" ];
```
`zfsutil` uses dataset properties as mount options such that zfsprops(7)
do not have to be duplicated in fstab(5) entries or manual mount(8)
invocations.
Given the example configuation above, /media is correctly mounted with
`setuid=off` translated into `nosuid`:
```
$ zfs get -Ho value setuid /media
off
$ findmnt -t zfs -no options /media
rw,nosuid,nodev,noexec,noatime,xattr,posixacl
```
/nix however was mounted with default mount(8) options:
```
$ zfs get -Ho value setuid /nix
off
$ findmnt -t zfs -no options /nix
rw,relatime,xattr,noacl
```
This holds true for all other ZFS properties/mount options, including
`exec/[no]exec`, `devices/[no]dev`, `atime/[no]atime`, etc.
/nix is mounted using BusyBox's `mount` during stage 1 init while /media
is mounted later using proper systemd and/or util-linux's `mount`.
Tracing stage 1 init showed that BusyBox never tried to execute
mount.zfs(8) as intended by `zfsutil`.
Replacing it with util-linux's `mount` and adding the mount helper
showed attempts to execute mount.zfs(8).
Ensure ZFS filesystems are mounted with correct options iff `zfsutil` is
used.
Very confusingly, the `isPowerPC` predicate in
`lib/systems/inspect.nix` does *not* match `powerpc64le`!
This is because `isPowerPC` is defined as
isPowerPC = { cpu = cpuTypes.powerpc; };
Where `cpuTypes.powerpc` is:
{ bits = 32; significantByte = bigEndian; family = "power"; };
This means that the `isPowerPC` predicate actually only matches the
subset of machines marketed under this name which happen to be 32-bit
and running in big-endian mode which is equivalent to:
with stdenv.hostPlatform; isPower && isBigEndian && is32bit
This seems like a sharp edge that people could easily cut themselves
on. In fact, that has already happened: in
`linux/kernel/common-config.nix` there is a test which will always
fail:
(stdenv.hostPlatform.isPowerPC && stdenv.hostPlatform.is64bit)
A more subtle case of the strict isPowerPC being used instead of the
moreg general isPower accidentally are the GHC expressions:
Update pkgs/development/compilers/ghc/8.10.7.nix
Update pkgs/development/compilers/ghc/8.8.4.nix
Update pkgs/development/compilers/ghc/9.2.2.nix
Update pkgs/development/compilers/ghc/9.0.2.nix
Update pkgs/development/compilers/ghc/head.nix
Since the remaining legitimate use sites of isPowerPC are so few, remove
the isPowerPC predicate completely. The alternative expression above is
noted in the release notes as an alternative.
Co-authored-by: sternenseemann <sternenseemann@systemli.org>