These make sense to be explicitly set at 0 (which has a different effect
than the default, since it can affect processing of `DefaultMemoryXXX`).
Without this, it's not easily possible to relinquish memory protection
for a subtree, which is not great.
Let's be safe, rather than sorry. This way DynamicUser=yes services can
neither take benefit of, nor create SUID/SGID binaries.
Given that DynamicUser= is a recent addition only we should be able to
get away with turning this on, even though this is strictly speaking a
binary compatibility breakage.
"BOOT" is misleading, because it sounds like this refers to /boot or $BOOT,
when in fact it refers to some subdirectory. Those variable names are purely
interal, so we can change them. $BOOT_DIR_ABS was used in NEWS, but it should
not be (because it is an internal detail), so the old NEWS entry is reworded to
use "entry directory".
Previously, this system call was included in @system-service since it is
a "getter" only, i.e. only queries information, and doesn't change
anything, and hence was considered not risky.
However, as it turns out, mincore() is actually security sensitive, see
the discussion here:
https://lwn.net/Articles/776034/
Hence, let's adjust the system call filter and drop mincore() from it.
This constitues a compatibility break to some level, however I presume
we can get away with this as the systemcall is pretty exotic. The fact
that it is pretty exotic is also reflected by the fact that the kernel
intends to majorly change behaviour of the system call soon (see the
linked LWN article)
These sysctls were added in Linux 4.19 (torvalds/linux@30aba6656f), and
we should enable them just like we enable the older hardlink/symlink
protection since v199. Implements #11414.
Nitpicky, but we've used a lot of random spacings and names in the past,
but we're trying to be completely consistent on "cgroup vN" now.
Generated by `fd -0 | xargs -0 -n1 sed -ri --follow-symlinks 's/cgroups? ?v?([0-9])/cgroup v\1/gI'`.
I manually ignored places where it's not appropriate to replace (eg.
"cgroup2" fstype and in src/shared/linux).
This reverts commit edda44605f.
The kernel explicitly supports resuming with a different kernel than the one
used before hibernation. If this is something that shouldn't be supported, the
place to change this is in the kernel. We shouldn't censor something that this
exclusively in the kernel's domain.
People might be using this to switch kernels without restaring programs, and
we'd break this functionality for them.
Also, even if resuming with a different kernel was a bad idea, we don't really
prevent that with this check, since most users have more than one kernel and
can freely pick a different one from the menu. So this only affected the corner
case where the kernel has been removed, but there is no reason to single it
out.
From WordNet (r) 3.0 (2006) [wn]:
time-out
n 1: a brief suspension of play; "each team has two time-outs left"
From The Free On-line Dictionary of Computing (18 March 2015) [foldoc]:
timeout
A period of time after which an error condition is raised if
some event has not occured. A common example is sending a
message. If the receiver does not acknowledge the message
within some preset timeout period, a transmission error is
assumed to have occured.
This switches the RFC3704 Reverse Path filtering from Strict mode to Loose
mode. The Strict mode breaks some pretty common and reasonable use cases,
such as keeping connections via one default route alive after another one
appears (e.g. plugging an Ethernet cable when connected via Wi-Fi).
The strict filter also makes it impossible for NetworkManager to do
connectivity check on a newly arriving default route (it starts with a
higher metric and is bumped lower if there's connectivity).
Kernel's default is 0 (no filter), but a Loose filter is good enough. The
few use cases where a Strict mode could make sense can easily override
this.
The distributions that don't care about the client use cases and prefer a
strict filter could just ship a custom configuration in
/usr/lib/sysctl.d/ to override this.
After discussions with kernel folks, a system with memcg really
shouldn't need extra hard limits on file descriptors anymore, as they
are properly accounted for by memcg anyway. Hence, let's bump these
values to their maximums.
This also adds a build time option to turn thiss off, to cover those
users who do not want to use memcg.
Back in 2012 the project was renamed, see the release notes for v 0.105
[https://cgit.freedesktop.org/polkit/tree/NEWS#n754]. Let's update our
documentation and comments to do the same. Referring to PolicyKit is confusing
to users because at the time the polkit api changed too, and we support the new
version. I updated NEWS too, since all the references to PolicyKit there were
added after the rename.
"PolicyKit" is unchanged in various URLs and method call names.
This is an additional synchronization point normally not needed. Hence,
let's make it passive, i.e. pull it in from the unit which wants to be
ordered before the update service rather than by the update service
itself.
We really should try to be as precise as possible here. Saying
"your interfaces might be renamed" scares the shit of out people,
for obvious reasons. This change only touches some niche cases
fortunately, let's make this clear.
I figure sooneror later we'll have more of these docs, hence let's give
them a clean place to be.
This leaves NEWS and README/README.md as well as the LICENSE texts in
the root directory of the project since that appears to be customary for
Free Software projects.
After discussions with @htejun it appears it's OK now to enable memory
accounting by default for all units without affecting system performance
too badly. facebook has made good experiences with deploying memory
accounting across their infrastructure.
This hence turns MemoryAccounting= from opt-in to opt-out, similar to
how TasksAccounting= is already handled. The other accounting options
remain off, their performance impact is too big still.
CHANGE OF BEHAVIOUR — with this commit "f" line's behaviour is altered
to match what the documentation says: if an "argument" string is
specified it is written to the file only when the file didn't exist
before. Previously, it would be appended to the file each time
systemd-tmpfiles was invoked — which is not a particularly useful
behaviour as the tool is not idempotent then and the indicated files
grow without bounds each time the tool is invoked.
I did some spelunking whether this change in behaviour would break
things, but afaics nothing relies on the previous O_APPEND behaviour of
this line type, hence I think it's relatively safe to make "f" lines
work the way the docs say, rather than adding a new modifier for it or
so.
Triggered by:
https://lists.freedesktop.org/archives/systemd-devel/2018-January/040171.html
With Type=notify services, EXTEND_TIMEOUT_USEC= messages will delay any startup/
runtime/shutdown timeouts.
A service that hasn't timed out, i.e, start time < TimeStartSec,
runtime < RuntimeMaxSec and stop time < TimeoutStopSec, may by sending
EXTEND_TIMEOUT_USEC=, allow the service to continue beyond the limit for
the execution phase (i.e TimeStartSec, RunTimeMaxSec and TimeoutStopSec).
EXTEND_TIMEOUT_USEC= must continue to be sent (in the same way as
WATCHDOG=1) within the time interval specified to continue to reprevent
the timeout from occuring.
Watchdog timeouts are also extended if a EXTEND_TIMEOUT_USEC is greater
than the remaining time on the watchdog counter.
Fixes#5868.
The code intentionally ignored unknown specifiers, treating them as text. This
needs to change because otherwise we can never add a new specifier in a backwards
compatible way. So just treat an unknown (potential) specifier as an error.
In principle this is a break of backwards compatibility, but the previous
behaviour was pretty much useless, since the expanded value could change every
time we add new specifiers, which we do all the time.
As a compromise for backwards compatibility, only fail on alphanumerical
characters. This should cover the most cases where an unescaped percent
character is used, like size=5% and such, which behave the same as before with
this patch. OTOH, this means that we will not be able to use non-alphanumerical
specifiers without breaking backwards compatibility again. I think that's an
acceptable compromise.
v2:
- add NEWS entry
v3:
- only fail on alphanumerical
This fixes various typos, removes some duplications, and adds a bit more
detail in the few places which are potential pitfalls for users.
Also change the way the paragraphs about new options begin, because having
a paragraph saying "Two new options have been added", and then bit lower
again "Two new options have been added" is confusing.
This creates a second private resolve.conf file which lists the stub resolver
and the resolved acquired search domains.
This runtime file should be used as a symlink target for /etc/resolv.conf such
that non-nss based applications can resolve search domains.
Fixes: #7009
This adds "systemd-resolve --reset-server-features" for explicitly
forgetting what we learnt. This might be useful for debugging
purposes, and to force systemd-resolved to restart its learning logic
for all DNS servers.
This removes the '@credentials' syscall set that was added in commit
v234-468-gcd0ddf6f75.
Most of these syscalls are so simple that we do not want to filter them.
They work on the current calling process, doing only read operations,
they do not have a deep kernel path.
The problem may only be in 'capget' syscall since it can query arbitrary
processes, and used to discover processes, however sending signal 0 to
arbitrary processes can be used to discover if a process exists or not.
It is unfortunate that Linux allows to query processes of different
users. Lets put it now in '@process' syscall set, and later we may add
it to a new '@basic-process' set that allows most basic process
operations.
Typically when DHCP server sets MTU it is a lower one. And a lower than usual
MTU is then thus required on said network to have operational networking. This
makes networkd's dhcp client to work in more similar way to other dhcp-clients
(e.g. isc-dhcp). In particular, in a cloud setting, without this default
instances have resulted in timing out talking to cloud metadata source and
failing to provision.
This does not change this default for the Annonymize code path.
They’re counterparts to the existing set-log-level and set-log-target
verbs, simply printing the current value to stdout. This makes it
slightly easier to temporarily change the log level and/or target and
then restore the old value(s).
This reverts commit 4f5e972279.
Building with gperf 3.0 works just fine; we had an autoconf check to
determine the correct data types, and this check was ported to meson.
Some .install plugins does not require that machine ID is set such as
20-grubby.install for Fedora and 50-depmod.install.
To support such plugins to run without valid machine-id, this commit
makes the following change:
* if /etc/machine-id is missing or empty, create temporary directory
and set its path to BOOT_DIR_ABS,
* run the .install helpers with KERNEL_INSTALL_MACHINE_ID environment
variable that'd be empty if /etc/machine-id is missing or empty.
This may be useful for installing kernel for e.g. stateless systems
which initialize machine-id while booting the systems.
If we could not communicate with systemd-resolved, we would call into
libnss_dns. libnss_dns would return NOTFOUND for stuff like "localhost" and
other names resolved by nss-myhostname, which we would fall under the !UNAVAIL=
condition and cause resolution to fail. So the following recommended
configuration in nsswitch.conf would not work:
hosts: resolve [!UNAVAIL=return] dns myhostname
Remove the internal fallback code completely so that the fallback logic
can be configured in nsswitch.conf.
Tested with
hosts: resolve [!UNAVAIL=return] myhostname
and
hosts: resolve [!UNAVAIL=return] dns myhostname
Fixes#5742.
This doesn't add anything major, but moves some stuff around.
In particular changes which might require updates to the build
environment (new kernel requirements, cgroup stuff, dbus, etc)
are moved to the top, where it's most likely that people will
read them. In particular cgroup hierarchy changes are moved to the
top because they're most likely to be problematic.
Various items are grouped by subject where it's easy.
The description of list-jobs --after/--before was reversed.
Apparently if people are adventurous enought to run Go programs in udev
rules they might run into problems with MemoryDenyWriteExecute=.
I am pretty sure the best way out is for the toolchain generating
programs incompatible with W^X to be fixed, but this still deserves
documentation.
This was forgotten for the 232 release, hence add it now, retroactively.
See: #5400
Let's make sure we verify that all BindsTo= are in order before we actually go
and dispatch a start operation to a unit. Normally the job queue should already
have made sure all deps are in order, but this might not have been sufficient
in two cases: a) when the user changes deps during runtime and reloads the
daemon, and b) when the user placed BindsTo= dependencies without matching
After= dependencies, so that we don't actually wait for the bound to unit to be
up before upping also the binding unit.
See: #4725
"sushell" is a Fedora-specific concept, shipped as part of
"initscripts". We shouldn't actively search for it if we can avoid it.
Hence, lets now default to /bin/sh as debug shell on all systems, and
permit Fedora to override that for their RPMs via --with-debug-shell= at
configure time.
Previously it was "[Yes, Fail, Skip]" which is pretty misleading because it
suggests that the whole word needs to be entered instead of a single char.
Also this won't fit well when we'll extend the number of choices.
This patch addresses this by changing the choice hint with "[y, f, s – h for help]"
so it's now clear that a single letter has to be entered.
It also introduces a new choice 'h' which describes all possible choices since
a single letter can be not descriptive enough for new users.
It also allow to stick with the same hint string regardless of how
many choices we will support.
Before this patch we had:
- "no" which gives "failing execution" but the command is actually assumed as
succeed.
- "skip" which gives "skipping", but the command is assumed to have failed,
which ends up with "Failed to start ..." on the console.
Now we have:
- "fail" which gives "failing execution" and the command is indeed assumed as
failed.
- "skip" which gives "skipping execution" and the command is assumed as
succeed.
Unfortunately, github drops the original commiter when a PR is "squashed" (even
if it is only a single commit) and replaces it with some rubbish
github-specific user id. Thus, to make the contributors list somewhat useful,
update the .mailmap file and undo all the weirdness github applied there.
Lennart Poettering