getty-generator: Use device hotplug to instantiate virtualizer consoles
If getty-generator runs in the initrd, the corresponding tty might not
have been instantiated yet in /dev, which means a serial getty is not
spawned on it. Instead, let's instantiate the serial-getty when the
device appears so that it always gets instantiated.
lsm-util: move detection of support of LSMs into a new lsm-util.[ch] helper
This makes the bpf LSM check generic, so that we can use it elsewhere.
it also drops the caching inside it, given that bpf-lsm code in PID1
will cache it a second time a stack frame further up when it checks for
various other bpf functionality.
Running systemd with IP accounting enabled generates many bpf maps (two
per unit for accounting, another two if IPAddressAllow/Deny are used).
Systemd itself knows which maps belong to what unit and commands like
`systemctl status <unit>` can be used to query what service has which
map, but monitoring these values all the time costs 4 dbus requests
(calling the .IP{E,I}gress{Bytes,Packets} method for each unit) and
makes services like the prometheus systemd_exporter[1] somewhat slow
when doing that for every units, while less precise information could
quickly be obtained by looking directly at the maps.
Unfortunately, bpf map names are rather limited:
- only 15 characters in length (16, but last byte must be 0)
- only allows isalnum(), _ and . characters
If it wasn't for the length limit we could use the normal unit escape
functions but I've opted to just make any forbidden character into
underscores for maximum brievty -- the map prefix is also rather short:
This isn't meant as a precise mapping, but as a hint for admins who want
to look at these.
(Note there is no problem if multiple maps have the same name)
process-util: be more careful with pidfd_get_pid() special cases
Let's be more careful with generating error codes for (expected) error
causes.
This does not introduce new error conditions, it just changes what we
return under specific cases, to make things nicely recognizable in each
case. Most importantly this detects if fdinfo reports a pid of "-1" for
pidfds with processes that are already reaped (and thus have no PID
anymore)
None of our current users care about these error codes, but let's get
this right for the future.
It'll be out this week. We can't update the man pages before it is realeased,
but we can use it for mkosi builds and do some very late testing.
Also, use filepath specification for /bin/pkg-config. We need it for meson, and
meson calls it directly by this path. pkgconfig is a virtual Provides on
pkgconf-pkg-config, and the indirection here just obfuscates things with no
benefit.
Add it explicitly for centos too. (I think it is pulled in by packages which
contain pkg-config modules anyway, but it's better to be explicit).
The cmd(3) man page says about CMSG_DATA():
> The pointer returned cannot be assumed to be suitably aligned for
> accessing arbitrary payload data types. Applications should not cast
> it to a pointer type matching the payload, but should instead use
> memcpy(3) to copy data to or from a suitably declared object.
Hence, if we want to use unaligned data in cmsg, we need to copy it
before use. That's typically important for reading timestamps in
RISCV32, as the time_t is 64bit and size_t is 32bit on the system.
This removes remaining hardcoded occurences of `/sbin/fsck`, and instead
uses `find_executable` to find `fsck`.
We also use `fsck_exists_for_fstype` to check for the `fsck.*`
executable, which also checks in `$PATH`, so it's fair to assume fsck
itself is also available.
The ignore directive specifies to not do anything with the given
unit and leave existing configuration intact. This allows distributions
to gradually adopt preset files by shipping a ignore * preset file.
man/systemd-cryptenroll: update list of PCRs, link to uapi docs
Entia non sunt multiplicanda praeter necessitatem. We had a list of PCRs in the
man page which was already half out-of-date. Instead, link to web page with the
"authoritative" list. Here, drop the descriptions of what shim and grub do. Instead,
just give some short descriptions and mention what systemd components do.
systemd-pcrmachine.service and systemd-pcrfs@.service are now mentioned too.
https://github.com/uapi-group/specifications/commit/d0e590b1e2648e76ece66157ceade3f45b165b14
extended the table in the specs repo.
https://github.com/uapi-group/specifications/pull/59 adds some more text there
too.
Also, rework the recommendation: hint that PCR 11 is useful, and recommend
binding to policy signatures instead of direct PCR values. This new text is
intentionally vague: doing this correctly is hard, but let's at least not imply
that just binding to PCR 7 is useful in any way.
Also, change "string alias" to "name" in discussion of PCR names.
Inspired by https://discussion.fedoraproject.org/t/future-of-encryption-in-fedora/80397/17
strstrafter() is like strstr() but returns a pointer to the first
character *after* the found substring, not on the substring itself.
Quite often this is what we actually want.
Inspired by #27267 I think it makes sense to add a helper for this,
to avoid the potentially fragile manual pointer increment afterwards.
The overflow check was hosed in two ways: overflows in C are undefined,
hence gcc was free to just optimize the whole thing away. We need to
catch overflows before we run into them, not after.
It checked for an overflow against size_t, but the field we need to
write this in is unsigned. i.e. typically 32bit rather than 64bit. Hence
check for the right maximum.
(The whole check is paranoia anyway, the kernel really shouldn't return
values that would induce an overflow, but you never know, the syscall
turned out to be problematic in so many other ways, hence let's stick to
this.)
mountpoint-util: pass AT_STATX_DONT_SYNC to statx() when looking for mnt_id/mountpoints
The concept of a "mount" is a local one, hence there's no point in going
to the network to retrieve mnt_id or STATX_ATTR_MOUNT_ROOT. Hence set
AT_STATX_DONT_SYNC so that the call will not go to the network ever, and
risk deadlocking on that.
When CHASE_MKDIR_0755 is specified without CHASE_NONEXISTENT and
CHASE_PARENT, then chase() succeeds only when the file specified by
the path already exists, and in that case, chase() does not create
any parent directories, and CHASE_MKDIR_0755 is meaningless.
Let's mention that CHASE_MKDIR_0755 needs to be specified with
CHASE_NONEXISTENT or CHASE_PARENT, and adds a assertion about that.
Luca Boccassi [Tue, 1 Nov 2022 23:34:15 +0000 (23:34 +0000)]
user units: implicitly enable PrivateUsers= when sandboxing options are set
Enabling these options when not running as root requires a user
namespace, so implicitly enable PrivateUsers=.
This has a side effect as it changes which users are visible to the unit.
However until now these options did not work at all for user units, and
in practice just a handful of user units in Fedora, Debian and Ubuntu
mistakenly used them (and they have been all fixed since).
This fixes the long-standing confusing issue that the user and system
units take the same options but the behaviour is wildly (and sometimes
silently) different depending on which is which, with user units
requiring manually specifiying PrivateUsers= in order for sandboxing
options to actually work and not be silently ignored.
Nick Rosbrook [Tue, 4 Apr 2023 22:39:26 +0000 (18:39 -0400)]
scope: do not disable timer event source when state is SCOPE_RUNNING
In scope_set_state(), the timer event source may be disabled depending
on the state. Currently, it will be disabled when the state is
SCOPE_RUNNING. This has the effect of new RuntimeMaxSec values being
ignored on coldplug.
Note that this issue is not currently present when scopes are started
because when scope_start() is called, scope_arm_timer() is called after
scope_set_state().
systemd-confext: mount confexts as noexec and nosuid
Confexts should not contain code, so mount confexts with noexec.
We cannot mount invidial extensions as noexec, as the overlay ignores
it and bypasses it, we need to use the flag on the whole overlay for
it to be effective.
But given there are legacy scripts still shipped in /etc, allow to
override it with --noexec=false.
Uphold/StopWhenUnneeded/BindsTo: requeue when job finishes
When a unit is upheld and fails, and there are no state changes in
the upholder, it will not be retried, which is against what the
documentation suggests.
Requeue when the job finishes. Same for the other two queues.
Sjoerd Simons [Thu, 23 Feb 2023 09:00:16 +0000 (10:00 +0100)]
repart: Discard from/to first/last usable lba
Repart considers the start and end of the usable space to the first multiple
of grainsz (at least 4096 bytes). However the first usable LBA of a GPT
partition is at sector 34 (512 bytes sectors) which is not a multiple of 4096.
The backup GPT label at the end also takes up 33 sectors, meaning the last
usable LBA is at 34 sectors from the end, unlikely to be a 4096 multiple as
well.
This meant that the very first and last sectors were never discarded. However
more problematically if an existing partition started before the first
usable grainsz multiple its start didn't get taken into account as a valid
starting point and got its data discarded.
socket-util: tighten aignment check for CMSG_TYPED_DATA()
Apparently CMSG_DATA() alignment is very much undefined. Which is quite
an ABI fuck-up, but we need to deal with this. CMSG_TYPED_DATA() already
checks alignment of the specified pointer. Let's also check matching
alignment of the underlying structures, which we already can do at
compile-time.
See: #27241
(This does not fix #27241, but should catch such errors already at
compile-time instead of runtime)
core: move runtime directory removal into release_resource handler
We already clear the various fds we keep from the release_resources()
handler, let's also destroy the runtime dir from there if this
preservation mode is selected.
This makes a minor semantic change: previously we'd keep a runtime
directory around if RuntimeDirectoryPreserve=restart is selected and at
least one JOB_START job was around. With this logic we'll keep it around
a tiny bit longer: as long as any job for the unit is around.
The file descriptors we keep in the fdstore might be basically anything,
let's clean it up with our asynchronous closing feature, to not
deadlock on close().
(Let's also do the same for stdin/stdout/stderr fds, since they might
point to network services these days.)
Now that we have a potentially pinned fdstore let's add a concept for
cleaning it explicitly on user requested. Let's expose this via
"systemctl clean", i.e. the same way as user directories are cleaned.
Oftentimes it is useful to allow the per-service fd store to survive
longer than for a restart. This is useful in various scenarios:
1. An fd to some security relevant object needs to be stashed somewhere,
that should not be cleaned automatically, because the security
enforcement would be dropped then.
2. A user namespace fd should be allocated on first invocation and be
kept around until the user logs out (i.e. systemd --user ends), á la
#16328 (This does not implement what #16318 asks for, but should
solve the use-case discussed there.)
3. There's interest in allow a concept of "userspace reboots" where the
kernel stays running, and userspace is swapped out (i.e. all services
exit, and the rootfs transitioned into a new version of it) while
keeping some select resources pinned, very similar to how we
implement a switch root. Thus it is useful to allow services to exit,
while leaving their fds around till the very end.
This is exposed through a new FileDescriptorStorePreserve= setting that
is closely modelled after RuntimeDirectoryPreserve= (in fact it reused
the same internal type), since we want similar behaviour in the end, and
quite often they probably want to be used together.
projects / thirdparty / systemd.git / log
