This adds a high level test verifying that syscall filtering in
combination with a simple architecture filter for the "native"
architecture works fine.
The commit 6597686865 ("seccomp: don't install filters for archs that
can't use syscalls") introduced a regression where filters may not be
installed for the "native" architecture. This means that setting
SystemCallArchitectures=native for a unit effectively disables the
SystemCallFilter= and SystemCallLog= options.
Conceptually, we have two filter stages:
1. architecture used for syscall (SystemCallArchitectures=)
2. syscall + architecture combination (SystemCallFilter=)
The above commit tried to optimize the filter generation by skipping the
second level filtering when it is not required.
However, systemd will never fully block the "native" architecture using
the first level filter. This makes the code a lot simpler, as systemd
can execve() the target binary using its own architecture. And, it
should be perfectly fine as the "native" architecture will always be the
one with the most restrictive seccomp filtering.
Said differently, the bug arises because (on x86_64):
1. x86_64 is permitted by libseccomp already
2. native != x86_64
3. the loop wants to block x86_64 because the permitted set only
contains "native" (i.e. "native" != "x86_64")
4. x86_64 is marked as blocked in seccomp_local_archs
Thereby we have an inconsistency, where it is marked as blocked in the
seccomp_local_archs array but it is allowed by libseccomp. i.e. we will
skip generating filter stage 2 without having stage 1 in place.
The fix is simple, we just skip the native architecture when looping
seccomp_local_archs. This way the inconsistency cannot happen.
The USB persist feature allows devices that can retain their state when
powered down to work across suspend/resume. This is in particular useful
for USB drives.
However, the persist feature can get in the way for devices that are
unable to retain their state when power is lost. An example of such
stateful devices are fingerprint readers where USB persist should be
disabled to ensure userspace can detect whether the USB device had a
power loss during system suspend.
This will initially be used by the libfprint autosuspend hwdb.
Closes: #20754
libfprint includes a list of known fingerprint readers that can be
autosuspended. Upstream libfprint generates this file from the USB IDs
registered to drivers and a list of well-known readers that are
currently unsupported.
Closes: #17663
This changes the default from putting all units into the root slice to
placing them into the app slice in the user manager. The advantage is
that we get the right behaviour in most cases, and we'll need special
case handling in all other cases anyway.
Note that we have currently defined that applications *should* start
their unit names with app-, so we could also move only these by creating
a drop-in for app-.scope and app-.service.
However, that would not answer the question on how we should manage
session.slice. And we would end up placing anything that does not fit
the system (e.g. anything started by dbus-broker currently) into the
root slice.
It is expected for numerous autostart files to not be convertible to
corresponding units. The information is only useful for someone
debugging why a file might not be started, but it is not generally
useful for users in most situations.
As such, lower the warnings. Anyone wondering why an application is not
started will easily notice that the unit is not generated. From there it
will be somewhat harder to figure out why, but the overall trade-off is
still improved.
Fixes: #17305
It makes sense to ignore all the common fields that are expected and
that we can safely ignore. Note that it is fine to ignore URL as we will
already warn about the type= being wrong in that case.
Closes: #17276
The description didn't really explain how the distribution mechanism
works exactly and the relationship of leaf and slice units.
Update the documentation and also explicitly explain the expected
behaviour as it is created by the memory_recursiveprot cgroup2 mount
option.
When available, enable memory_recursiveprot. Realistically it always
makes sense to delegate MemoryLow= and MemoryMin= to all children of a
slice/unit.
The kernel option is not enabled by default as it might cause
regressions in some setups. However, it is the better default in
general, and it results in a more flexible and obvious behaviour.
The alternative to using this option would be for user's to also set
DefaultMemoryLow= on slices when assigning MemoryLow=. However, this
makes the effect of MemoryLow= on some children less obvious, as it
could result in a lower protection rather than increasing it.
From the kernel documentation:
memory_recursiveprot
Recursively apply memory.min and memory.low protection to
entire subtrees, without requiring explicit downward
propagation into leaf cgroups. This allows protecting entire
subtrees from one another, while retaining free competition
within those subtrees. This should have been the default
behavior but is a mount-option to avoid regressing setups
relying on the original semantics (e.g. specifying bogusly
high 'bypass' protection values at higher tree levels).
This was added in kernel commit 8a931f801340c (mm: memcontrol:
recursive memory.low protection), which became available in 5.7 and was
subsequently fixed in kernel 5.7.7 (mm: memcontrol: handle div0 crash
race condition in memory.low).
If an autostart file for GNOME has a phase specified, then this implies
it is a session service that needs to be started at a specific time.
We have no way of handling the ordering, and while it does make sense
to explicitly hide these services with X-systemd-skip, there is no point
in even trying to handle them.
This generator can be used by desktop environments to launch autostart
applications and services. The feature is an opt-in, triggered by
xdg-desktop-autostart.target being activated.
Also included is the new binary xdg-autostart-condition. This binary is
used as an ExecCondition to test the OnlyShowIn and NotShowIn XDG
desktop file keys. These need to be evaluated against the
XDG_CURRENT_DESKTOP environment variable which may not be known at
generation time.
Co-authored-by: Henri Chain <henri.chain@enioka.com>
We need both a slice name and a prefix for application units. For
consistency we tried to use the same name and ended up standardising on
"apps.slice" and and "apps-" prefix for the units.
However, "app-" would be a more natural prefix for applications. And it
is no problem to simply also name the slice "app.slice" for consistency
rather than keeping the current "apps.slice".
This is work in progress and not finished yet. However, I hope to have
captured some of the key points that came up in previous discussions
with appropriate notes about things that still need to be defined.
I may revisit it later. Also, feel free to completely rewrite if the
format is not quite right.
When using the cgroups IO controller, the device that is controlled
should always be the toplevel block device. This did not get resolved
correctly for an LVM volume inside a LUKS device, because the code would
only resolve one level of indirection.
Fix this by recursively looking up the originating block device for DM
devices.
Resolves: #15008
This adds documentation for the SYSTEMD_GENERATOR_PATH and
SYSTEMD_ENVIRONMENT_GENERATOR_PATH variables to the systemd man page
grouped with the existing SYSTEMD_UNIT_PATH.
Also added is a description about how these variables work, i.e. that a
trailing : can be used to prepend paths to the usual set.
This adds SYSTEMD_GENERATOR_PATH and SYSTEMD_ENVIRONMENT_GENERATOR_PATH
environment variables that will be read in the same manner as
SYSTEMD_UNIT_PATH is. i.e. if set, these paths will be used and a
trailing empty entry means that the usual paths will be appended, while
no trailing entry means that solely the given paths are used.
On these devices the key randomly fires during/after suspend/resume
triggering spurious airplane mode changes. The scancode simply needs to
be ignored.
In certain cases the timeouts may not have been unref'ed before they
need to be re-added. Add the appropriate unref calls to ensure we don't
register the timeout multiple times.
This fixes possible cases where timeouts are triggered multiple times
and even on destroyed DHCPv6 clients.
https://gitlab.freedesktop.org/NetworkManager/NetworkManager/issues/73Fixes#10749.
On thinkpads there are two rfkill devices for bluetooth. The first is an
ACPI switch which powers down the USB dongle and the second one is the
USB dongle itself. So when userspace decides to enable rfkill on all
devices systemd would randomly save the soft block state of the USB
dongle. This later causes issue when re-enabling the devie as
systemd-rfkill would put the USB dongle into soft block state right
after the ACPI rfkill switch is unblocked by userspace.
The simple way to avoid this is to not store rfkill changes for devices
that disappear shortly after. That way only the "main" ACPI switch will
get stored and systemd-rfkill will not end up blocking the device right
after it is being added back again.
Benjamin Berg
