Commit Graph
168 Commits
Author SHA1 Message Date
Luca Boccassi e67b008fa3 journald: set a lower size limit for FDs from unpriv processes
Unprivileged processes can send 768M in a FD-based message to journald,
which will be malloc'ed in one go, likely causing memory issues.
Set the limit for unprivileged users to 24M.

Allow coredumps as an exception, since we always allowed storing
up to the 768M max core files in the journal.

Reported on yeswehack.com as #YWH-PGM9780-48
2026-02-09 13:51:59 +01:00
DaanDeMeyer 995c507a6f nss-util: Add support for $SYSTEMD_NSS_LOG_LEVEL
When setting SYSTEMD_LOG_LEVEL=debug and debugging a tool that happens
to do NSS lookups, the resulting logs from varlink are obnoxiously
verbose. Let's parse a separate log level environment variable in NSS
to allow overriding the log level for NSS specifically so these noisy
logs can be silenced.
2026-01-21 12:03:07 +01:00
Lennart Poettering d0badc0a61 sysupdate: add simple "freshness" validation to systemd-sysupdate
In order to make "freeze" attacks against the update logic harder let's
add the ability to encode a "Best Before" date into SHA256SUMS directory
listings: if the current time is already beyond that time, we'll ignore
the SHA256SUMS as "stale" and fail the upgrade. Or in other words: the
freeze attack will now result in a client-side error eventually, instead
of success state.

The best before data is encoded in an optional pseudo-file listed in SHA256SUMS:
any file named BEST-BEFORE-YYYY-MM-DD.
2026-01-20 21:22:35 +01:00
Yu Watanabe 0a2cdd5891 Drop remaining references about sysv script support
Follow-up for 986fee6217.
2026-01-16 22:56:08 +09:00
Luca Boccassi 986fee6217 Drop support for sysvinit scripts
As announced by a few releases now, finally drop support for
sysvinit scripts.
Keep rc-local generator for now, as it's really a distinct
feature even though from the same era.
2026-01-06 10:34:02 +01:00
Lennart Poettering 81b52a013c docs: reference UAPI specs by their number when linked 2025-11-23 17:16:09 +01:00
Lennart Poettering e30738c20c dissect-tool: accept encryption password via $PASSWORD 2025-11-17 16:42:58 +01:00
Francesco VallaandEric Curtin 840549989f modules-load: implement parallel module loading
Load modules in parallel using a pool of worker threads. The number of
threads is equal to the number of CPUs, with a maximum of 16 (to avoid
too many threads being started during boot on systems with many an high
core count, since the number of modules loaded on boot is usually on
the small side).

The number of threads can optionally be specified manually using the
SYSTEMD_MODULES_LOAD_NUM_THREADS environment variable; in this case,
no limit is enforced. If SYSTEMD_MODULES_LOAD_NUM_THREADS is set to 0,
probing happens sequentially.

Co-authored-by: Eric Curtin <ecurtin@redhat.com>
2025-11-07 14:12:56 +01:00
Daan De Meyer 9c3359f28a ptyfwd: Always prioritize $SYSTEMD_TINT_BACKGROUND
By giving priority to --background= we prevent users from opting
out of coloring if an explicit color is chosen by a tool wrapping
one of our own tools. Instead, let's give priority to the environment
variable, so that even if our tools are wrapped by another tool with
a different background, users can still opt out of coloring just by
setting the environment variable, which has a high chance of being
forwarded to the invocation of our own tools which makes it easy to
use to disable color tinting globally if requested by the user.
2025-10-20 12:20:35 +02:00
Nick Labich 942ad8503a sysext: Configure overlayfs mount options via envvar
Implements #39314
2025-10-20 09:59:02 +02:00
Lennart Poettering aad0d11e7c dissect-image: when autoprobing insist on vfat for XBOOTLDR
Let's reduce our attack surface by insisting that XBOOTLDR is vfat when
auto-probing, just like we do for the ESP. Given neither can
realistically be integrity protected (because firmware needs to access
them) let's insist on a vfat which has a much smaller attack surface,
and one we have to accept (for now) anyway, given that the ESP must be
VFAT.

This only applies to auto-probing of course. If people mount things
explicitly via fstab none of this matters. But we really shouldn't
automount a btrfs/xfs/ext4 partition as XBOOTLDR just because it looks
like one, as that would really defeat our otherwise possibly very strict
image policies.

This also introduces a new env var $SYSTEMD_DISSECT_FSTYPE_<DESIGNATOR>
environment variable that may override this hardcoding. This is in
particular useful in our testcases, since various actually do use ext4
as XBOOTLDR case. The tests are updated to make use of the new env var,
both as a mechanism to test this and to keep the tests working.
2025-10-15 08:32:37 +02:00
Lennart Poettering 57d1ceffb3 dissect-image: turn verity device sharing into opt-in
Sharing verity volumes is problematic for a veriety of reasons, for
example because it might pin the wrong backing device at the wrong time.

Let's hence turn this around: unless verity sharing is enabled, leave it
off, and turn $SYSTEMD_VERITY_SHARING into a true boolean that can be
set both ways.

The primary usecase for verity sharing is RootImage=, where it probably
makes sense to leave on, hence set the flag there.

This is crucial when putting together installers which install an OS on
a second disk: if verity sharing is always on we might mount the wrong
of the two disks at the wrong time.
2025-10-13 22:13:53 +02:00
ners 7b7f0983e0 localectl: use XKB path specified from environment variable 2025-09-19 15:37:52 +09:00
Yu Watanabe ed9c82095a assert-util: introduce log_set_assert_return_is_critical_from_env()
It will be used for testing nss modules.
2025-08-17 00:14:42 +09:00
Zbigniew Jędrzejewski-Szmek b68b9f8f7f docs/ENVIRONMENT: fix typo and adjust grammar 2025-07-29 11:36:21 +02:00
Valentin David 0dc39dffbd Use paths specified from environment variables for /etc configuration files
Some configuration files that need updates are directly under in /etc. To
update them atomically, we need write access to /etc. For Ubuntu Core this is
an issue as /etc is not writable. Only a selection of subdirectories can be
writable. The general solution is symlinks or bind mounts to writable places.
But for atomic writes in /etc, that does not work. So Ubuntu has had a patch
for that that did not age well.

Instead we would like to introduce some environment variables for alternate
paths.

 * SYSTEMD_ETC_HOSTNAME: /etc/hostname
 * SYSTEMD_ETC_MACHINE_INFO: /etc/machine-info
 * SYSTEMD_ETC_LOCALTIME: /etc/localtime
 * SYSTEMD_ETC_LOCALE_CONF: /etc/locale.conf
 * SYSTEMD_ETC_VCONSOLE_CONF: /etc/vconsole.conf
 * SYSTEMD_ETC_ADJTIME: /etc/adjtime

While it is for now expected that there is a symlink from the standard, we
still try to read them from that alternate path. This is important for
`/etc/localtime`, which is a symlink, so we cannot have an indirect symlink or
bind mount for it.

Since machine-id is typically written only once and not updated. This commit
does not cover it. An initrd can properly create it and bind mount it.
2025-06-23 15:32:11 +02:00
Yu Watanabe 27546b769c sd-lldp-tx: do not expose machine ID by default
Previously, systemd-networkd sent machine ID as chassis ID.
Let's use application specific machine ID.

This is a kind of backward compat breaking. Hence, this also introduces
the support of $SD_LLDP_SEND_MACHINE_ID environment variable.

Closes #37613.
2025-06-18 00:53:20 +09:00
Mike Yuan 6801a9d88a nspawn: drop cgroup v1 handling 2025-04-04 14:36:11 +02:00
Lennart Poettering e34c89897a dissect-image: guess verity root hash from the resources we found
When dissecting an image, let's make use of the Verity data even if we
got told no root hash explicitly: we can simply determine it by
concatenating the data partition uuid with the verity partition uuid.

Of course, on first thought this doesn't really add much: if the root
hash is not pinned from somewhere, this does not guarantee trust in
the image.

However, this is very useful for attestation: if we have the root hash
we can measure it before mounting things, even if we don't actually
authenticate it.

Hence, at best this helps us with attestation, at worst it doesn't improve
security but certainly doesn't hurt it.
2025-04-03 11:08:57 +02:00
Lennart Poettering 4f00011b68 homectl: add a 'dry-run' mode for registering/creating users
Since this only covers user creation/registration for now, let's hide it
behind an env var. We might reconsider this eventually and make it a
proper switch one day, but who knows, it after all has this "debug tool"
wiff.
2025-03-07 18:14:14 +01:00
Lennart Poettering 73e53d2ee4 tpm2-clear: optionally reset TPM during a factory reset 2025-03-05 12:37:51 +01:00
Daan De Meyer daa2547e31 Add a few more bypass environment variables
When we're building ParticleOS images, we don't want the package
manager (or mkosi) to run systemd-sysusers, systemd-tmpfiles or
systemctl preset so let's add a few more bypass environment
variables that we can set to have execution of these skipped like
we already have $SYSTEMD_HWDB_UPDATE_BYPASS and $KERNEL_INSTALL_BYPASS.
2025-03-01 16:22:53 +01:00
Lennart Poettering 14871a6529 efivars: kill SystemdOptions efi var support
This has been depracted since v254 (2023). Let's kill it for
good now, it has been long enough with 2y. Noone has shown up who wants
to keep it. And given it doesn't work in SB world anyway, and is not
measured is quite problematic security wise.
2025-02-26 17:28:43 +01:00
Lennart Poettering cfe16540c8 homectl: optionally force interactive firstboot query 2025-02-17 15:21:18 +01:00
Daan De Meyer 36c6c696a7 ask-password: Add $SYSTEMD_ASK_PASSWORD_KEYRING_TYPE
Currently ask_password_auto() will always try to store the password into
the user keyring. Let's make this configurable so that we can configure
ask_password_auto() into the session keyring. This is required when working
with user namespaces, as the user keyring is namespaced by user namespaces
which makes it impossible to share cached keys across user namespaces by using
the user namespace while this is possible with the session keyring.
2024-11-02 23:20:57 +01:00
Daan De Meyer 01d138b990 ask-password: Drop "default" for SYSTEMD_ASK_PASSWORD_KEYRING_TIMEOUT_SEC
Users can simply unset the environment variable to achieve the same effect.
2024-11-02 23:20:57 +01:00
Daan De Meyer d9f4dad986 ask-password: Allow configuring the keyring timeout via an environment variable
In mkosi, we want an easy way to set the keyring timeout for every
tool we invoke that might use systemd-ask-password to query for a
password which is then stored in the kernel keyring. Let's make this
possible via a new $SYSTEMD_ASK_PASSWORD_KEYRING_TIMEOUT_SEC environment
variable.

Using an environment variable means we don't have to modify every separate
tool to add a CLI option allowing to specify the timeout. In mkosi specifically,
we'll set up a new session keyring for the mkosi process linked to the user keyring
so that any pins in the user keyring are used if available, and otherwise we'll query
for and store password in mkosi's session keyring with a zero timeout so that they stay
in the keyring until the mkosi process exits at which point they're removed from the
keyring.
2024-10-30 17:43:53 +01:00
xujing cc2030f928 pid1: add env var to override default mount rate limit interval
Similar to 24a4542c. 24a4542c can only be set 1 in 1s at most,
sometimes we may need to set to something else(such as 1 in 2s).
So it's best to let the user decide.

This also allows users to solve #34690.
2024-10-16 16:07:26 +02:00
Gaël PORTAY 8ef5ea2bf6 docs: add a missing : character
This adds the missing colon character to the section systemd-sysusers.
2024-10-14 20:11:44 +01:00
Daan De Meyer 2701c2f67d Add $SYSTEMD_IN_CHROOT to override chroot detection
When running unprivileged, checking /proc/1/root doesn't work because
it requires privileges. Instead, let's add an environment variable so
the process that chroot's can tell (systemd) subprocesses whether
they're running in a chroot or not.
2024-08-16 10:11:29 +02:00
Daan De Meyer 90a255779d repart: Allow overriding fstype per partition designator
$SYSTEMD_REPART_OVERRIDE_FSTYPE is too invasive. Often you want to
override the fstype only for a specific designator, so let's support
that as well.
2024-07-03 15:45:51 +02:00
Zbigniew Jędrzejewski-Szmek cddbd730cb Merge pull request #33370 from grawity/run-title
run: add option to prevent the setting of terminal title
2024-06-28 14:46:27 +02:00
Lennart Poettering ab89c6d162 varlink: if $SYSTEMD_VARLINK_LISTEN is set to "-", listen on stdio 2024-06-27 10:52:23 +02:00
Mantas Mikulėnas 27a2513013 run: add environment variable to prevent the setting of terminal title
This goes together with the existing SYSTEMD_TINT_BACKGROUND.

Closes https://github.com/systemd/systemd/issues/33301
2024-06-25 10:39:15 +03:00
Lennart Poettering afc55a5eff bus-util: add env var for disabling exit-on-idle 2024-06-12 12:53:53 +02:00
Colin Watson 566491c971 docs,man: Avoid some ambiguous uses of "may not"
Like much English text, the systemd documentation uses "may not" in the
sense of both "will possibly not" and "is forbidden to".  In many cases
this is OK because the context makes it clear, but in others I felt it
was possible to read the "is forbidden to" sense by mistake: in
particular, I tripped over "the target file may not exist" in
systemd.unit(5) before realizing the correct interpretation.

Use "might not" or "may choose not to" in these cases to make it clear
which sense we mean.
2024-05-08 17:14:32 +02:00
Lennart Poettering d4ffb37bb1 nspawn, vmspawn, run0: add env var for turning off background tinting
Some people are just sad, sad lost souls who don't like even the tiniest
ray of color in their life. Let's add an env var knob for allowing them
to turn the background tinting off, to drive the last bit of color from
their life so that they can stay in their grey grey life.
2024-05-02 23:33:39 +02:00
Lennart Poettering 6f9a1adf6d vmspawn: add env var that can extend the qemu cmdline
This is a bit hackish, but really useful sometimes to play around with
some qemu switches.
2024-04-20 12:10:42 +02:00
Sam Leonard c3dd4e20fe vmspawn: generate predicatable TAP device names and MAC addresses 2024-04-15 11:42:06 +01:00
Lennart Poettering 702a52f4b5 mountfsd: add new systemd-mountfsd component 2024-04-06 16:08:24 +02:00
Krzesimir Nowak 33cb10f68d docs: Document SYSTEMD_SYSEXT_MUTABLE_MODE env var 2024-03-25 08:14:36 +01:00
Luca Boccassi 15d4bedf3d Merge pull request #31778 from yuwata/kbd-util
kbd-util: allow to override the default keymap directories
2024-03-18 12:20:36 +00:00
Yu Watanabe 013359ac65 network: pin file descriptor of persistent storage
This also drop the support of /run/systemd/netif/persistent-storage-ready,
as the file is anyway removed when networkd is stopped.
Let's use $SYSTEMD_NETWORK_PERSISTENT_STORAGE_READY=1 instead on testing.
2024-03-16 01:12:05 +09:00
Yu Watanabe e852f10cb4 kbd-util: allow to override the default keymap directories
This introduces $SYSTEMD_KEYMAP_DIRECTORIES environment variable to
override the hardcoded keymap directories.

I think it is not necessary to provide the first class configuration
option for controlling the keymap directories, but it is not good to
hardcode the paths. So, let's introduce an environment variable to
override that.

Prompted by #31759.

Closes #31759.
2024-03-15 03:19:45 +09:00
Lennart Poettering 74d142ff3a Merge pull request #30612 from AdrianVovk/sleep-freeze-user-seesions
Freeze user sessions for all types of sleep
2024-03-06 18:52:57 +01:00
Adrian Vovk a5b009d935 homework: Lock/Unlock: Freeze/Thaw user session
Whenever a home directory is in a locked state, accessing the files of
the home directory is extremely likely to cause the thread to hang. This
will put the session in a strange state, where some threads are hanging
due to file access and others are not hanging because they are not
trying to access any of the user's files.

This can lead to a whole slew of consequences. For example, imagine a
likely situation where the Wayland compositor is not hanging, but the
user's open apps are. Eventually, the compositor will detect that none
of the apps are responding to its pings, assume that they're frozen
(which they are), and kill them. The systemd user instance can end up in
a similarly confused state and start killing user services. In the worst
case, killing an app at an unexpected moment can lead to data loss.

The solution is to suspend execution of the whole user session by
freezing the user's slice.
2024-03-05 12:12:36 -05:00
Adrian Vovk 0b958bb3ee sleep: Always freeze user.slice
Previously, we'd only freeze user.slice in the case of s2h, because we
didn't want the user session to resume while systemd was transitioning
from suspend to hibernate.

This commit extends this freezing behavior to all sleep modes.

We also have an environment variable to disable the freezing behavior
outright. This is a necessary workaround for someone that has hooks
in /usr/lib/systemd/system-sleep/ which communicate with some
process running under user.slice, or if someone is using the proprietary
NVIDIA driver which breaks when user.slice is frozen (issue #27559)

Fixes #27559
2024-03-05 12:12:35 -05:00
Lennart Poettering 6399be223b resolved: make resolved authoritative in resolveing our local host name
This is a kinda a follow-up for ce266330fc: it
makes resolved authoritative on our local hostname, and never contacts
DNS anymore for it.

We effectively already were authoritative for it, except if the user
queried for other RR types than just A/AAAA. This closes the gap and
refuses routing other RR type queries to DNS.

Fixes: #23662
2024-03-05 15:31:32 +01:00
Luca Boccassi a73144bbdf repart: add --private-key-source and drop --private-key-uri
It turns out it's mostly PKCS11 that supports the URI format,
and other engines just take files. For example the tpm2-tss-openssl
engine just takes a sealed private key file path as the key input,
and the engine needs to be specified separately.

Add --private-key-source=file|engine:foo|provider:bar to
manually specify how to use the private key parameter.

Follow-up for 0a8264080a
2024-03-01 17:32:19 +00:00
Lennart Poettering 5b97957376 Merge pull request #31531 from poettering/verity-userspace-optional
dissect: make use of userspace verity keyring optional
2024-02-28 22:04:58 +01:00