We don't want to vacuum anything if we're just going to fail just
afterwards because a GPT partition label exceeds the maximum size
so let's compute the temporary paths for all transfers before we do
any vacuuming or acquiring.
These expose the two parts of ‘update’, so that update sets can be
acquired (downloaded) and installed (applied) in separate actions at
different times. For example, this could allow a load of update sets to
be acquired when online, and later applied when offline.
Signed-off-by: Philip Withnall <pwithnall@gnome.org>
Helps: https://github.com/systemd/systemd/issues/34814
An ‘acquire’ (download) part, and an ‘install’ (apply) part.
Following commits will expose these as separate verbs and D-Bus methods,
but this commit is the one which rearranges the internals.
If doing an ‘install’, a mirror version of the ‘acquire’ has to happen
first to make sure the transfer’s internal state is correct.
‘Acquire’ can require an internet connection, but ‘install’ will always
work with `--offline` specified.
Signed-off-by: Philip Withnall <pwithnall@gnome.org>
Helps: https://github.com/systemd/systemd/issues/34814
This commit adds the flags and some basic formatting/printing of them.
Following commits will integrate them into the update/acquire/install
logic.
`UPDATE_PARTIAL` is set if any of the instances in the `UpdateSet` are
partial, i.e. have been partially downloaded.
`UPDATE_PENDING` is set if any of the instances in the `UpdateSet` are
pending, i.e. have been acquired (downloaded) but not yet installed.
Signed-off-by: Philip Withnall <pwithnall@gnome.org>
Helps: https://github.com/systemd/systemd/issues/34814
Modify the vacuum implementation to preferentially vacuum partial or
pending transfers first (unless protected) as they are meant to be
fairly transitory, and ones which are hanging around have probably been
forgotten about and/or are out of date.
Signed-off-by: Philip Withnall <pwithnall@gnome.org>
Helps: https://github.com/systemd/systemd/issues/34814
Instead of using a random temporary path for file transfers, use a
predictable one which indicates whether the transfer is partially
complete or pending installation. Similarly for partitions.
This is another step towards being able to split the ‘update’ step into
‘acquire’ and ‘install’.
Signed-off-by: Philip Withnall <pwithnall@gnome.org>
Helps: https://github.com/systemd/systemd/issues/34814
If we allow target instances to be partial or pending, we can build on
top of this to allow updates to be split into two phases: ‘acquire’ (which
takes an available source instance and copies it (temporarily partial) to
a pending target instance; and ‘install’ (which takes a pending target
instance and installs it as an installed target instance).
This commit introduces a file/directory and partition prefix naming
scheme to identify partial and pending instances.
Signed-off-by: Philip Withnall <pwithnall@gnome.org>
Helps: https://github.com/systemd/systemd/issues/34814
get_block_device_harder_fd() currently only traverses one level of
device mapper stacking when looking for the underlying block device.
This causes issues with nested DM setups like dm-crypt on top of
dm-integrity, where we don't traverse enough to get the actual physical
device.
Fix this by iterating through all DM layers until we reach a device with
no underlying device. And while we're at it also make cgroups use the
same logic.
Fixes: #40419
Let's make sure we can safely load configuration files based on a root
fd, including XAT_FDROOT.
(While we are at it, always pass path to root fs before fd to root fs,
following our recently updated CODING_STYLE)
Originating device lookups currently use separate entry points and
callers must decide between the single-step helper and manual looping.
Add a recursive flag to block_device_get_originating() and
block_get_originating(), and update callers to pass an explicit value.
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.
Follow-up for 179dcf924f
After the mentioned commit, event_add_child_pidref() duplicates
the pidfd internally, hence the original pidfd would be leaked
with TAKE_PIDREF.
Let's introduce these for the following two reasons:
- Using them makes sure the parameter names match between declaration
and definition (if both use the corresponding macros).
- They make sure developers can't forget the _const_ and _pure_
attributes for the declarations.
This commit also includes some include sorting fixes
Now that sd-event doesn't insist on blocking
SIGCHLD anymore when watching for process exit,
let's stop blocking SIGCHLD tree-wide where not
required anymore.
In all cases, everything that we list in 'extract', we also list in
'sources'. We can simplify things by automatically appending the first
list to the second.
In the listings, move 'extract' key right below 'sources', since now
they are both "sources", just with slightly different meanings.
- Make sure forward headers have the iwyu pragma to always keep them
- Make sure we always include the daemon specific forward header
instead of shared-forward.h
- Remove shared-forward.h include where the daemon specific forward
header is already included
Let's not leak details from src/shared and src/libsystemd into
src/basic, even though you can't actually do anything useful with
just forward declarations from src/shared.
The sd-forward.h header is put in src/libsystemd/sd-common as we
don't have a directory for shared internal headers for libsystemd
yet.
Let's also rename forward.h to basic-forward.h to keep things
self-explanatory.
Since c5de7b14ae
file searching implies a new mount api syscall by default,
to trigger automounts.
But, this is not necessary in most cases, e.g. when chasing
syspath in sd-device (actually this causes regression in umockdev,
see https://github.com/martinpitt/umockdev/issues/271).
Another example is reading unit files, especially .network files,
as automount may trigger mounting network filesystems...
Also, when this is used in NSS plugins, programs that load the
plugins may fail because of spuriously configured seccomp. See #38565.
Let's not trigger automount by default, and do only when explicitly
requested.
This introduces CHASE_TRIGGER_AUTOFS, and use it in
- service manager,
- bootctl and finding ESP/xbootldr,
- sysupdate,
- mountfsd,
- systemd-mount.
There may be several more places we should trigger automount, but let's
do that later.
Follow-up for c5de7b14ae.
Fixes#38565.
Replaces #38569.
Co-authored-by: Luca Boccassi <luca.boccassi@gmail.com>
This reverts commit 490aa05ca1.
As commented https://github.com/systemd/systemd/pull/38569#discussion_r2284978273,
the commit makes autofs check bypassed. Before the commit, when
CHASE_NO_AUTOFS is set, we did not shortcut chasing paths, and refused
any autofs mount points in the path. However, with the commit, the flag
was swapped but even when CHASE_AUTOFS is unset, the autofs check may be
skipped.
To fix the issue, rather than swapping the flag, we should introduce
another flag, say CHASE_TRIGGER_AUTOFS. This revert the commit, and in a
later commit, the new flag will be introduced.
Since c5de7b14ae
file searching implies a new mount api syscall by default,
to trigger automounts.
This is problematic in NSS plugins, as they are dlopen'ed inside
processes by glibc, for two reasons.
First of all, potentially searching on a networked filesystem
automount could lead to nasty surprises, such as the process
responsible for setting up the network filesystem trying to
search on that same filesystem.
More importantly, the new mount api syscall was never part of
the filesystem seccomp filter that we provide by default, and
given mounting/remounting/bind mounting is one of the possible
ways to bypass sandboxing it is very likely not allowed when
custom filters are used in sandboxed processes, if they don't
need to do these operations otherwise.
The filesystem seccomp mask we provide has been updated, however
this only takes effect on the next restart of a service. When
systemd is upgraded via a package upgrade, the new nss plugin is
installed and will be immediately dlopen'ed by glibc when needed,
without waiting for the process to restart, which means the existing
seccomp filter applies, causing the filter to trigger.
Given it's not really possible for any arbitrary program to
predict which NSS modules glibc will load, given programs do not
configure that and instead nsswitch is set up by the sysadmin,
it's impossible to handle at each process level. It's also not
possible to know when it will be triggered, given the plugin
is not linked in each binary tools like need-restart cannot
even pre-emptively restart services that may be affected.
This means in practice, upgrading from systemd << v258 to >= v258
requires a reboot to avoid either subtle or catastrophic system
failures.
By avoiding to trigger automounts in nss-systemd we can avoid
both issues.
userdb drop-ins are searched for in:
/etc/userdb/
/run/userdb/
/run/host/userdb/
/usr/local/lib/userdb/
/usr/lib/userdb/
none of which are supported as automounts anyway.
Note that this happens only when the userdbd service is not running,
as otherwise nss-systemd will go through the varlink IPC, rather than
doing the searches in-process.
So invert CHASE_NO_AUTOFS to CHASE_AUTOFS and set it in the places where
we do want to trigger automounts, like looking for the ESP.
Follow-up for c5de7b14ae
Fixes https://github.com/systemd/systemd/issues/38565
We use symbols provided by unistd.h without including it. E.g.
open(), close(), read(), write(), access(), symlink(), unlink(), rmdir(),
fsync(), syncfs(), lseek(), ftruncate(), fchown(), dup2(), pipe2(),
getuid(), getgid(), gettid(), getppid(), pipe2(), execv(), _exit(),
environ, STDIN_FILENO, STDOUT_FILENO, STDERR_FILENO, F_OK, and their
friends and variants, so on.
Currently, unistd.h is indirectly included mainly in the following two paths:
- through missing_syscall.h, which is planned to covert to .c file.
- through signal.h -> bits/sigstksz.h, which is new since glibc-2.34.
Note, signal.h is included by sd-eevent.h. So, many source files
indirectly include unistd.h if newer glibc is used.
Currently, our baseline on glibc is 2.31. We need to support glibc older
than 2.34, but unfortunately, we do not have any CI environments with
such old glibc. CIFuzz uses glibc-2.31, but it builds only fuzzers, and
many files are even not compiled.
