Adding --image parameter for verify verb using the dissect image functionality
-----------------------------------------------------------------------------------
Example Run:
I created a unit service file testrun.service with an invalid key-value pairing
(foo = bar) and a squashfs image run.raw to test the code.
maanya-goenka@debian:~/systemd (img-support)$ cat <<EOF>img/usr/lib/systemd/system/testrun.service
> [Unit]
> foo = bar
>
> [Service]
> ExecStart = /opt/script0.sh
> EOF
maanya-goenka@debian:~/systemd (img-support)$ mksquashfs img/ run.raw
Parallel mksquashfs: Using 4 processors
Creating 4.0 filesystem on run.raw, block size 131072.
[==============================================================================================================================|] 6/6 100%
Exportable Squashfs 4.0 filesystem, gzip compressed, data block size 131072
compressed data, compressed metadata, compressed fragments, compressed xattrs
duplicates are removed
Filesystem size 0.60 Kbytes (0.00 Mbytes)
52.32% of uncompressed filesystem size (1.14 Kbytes)
Inode table size 166 bytes (0.16 Kbytes)
43.01% of uncompressed inode table size (386 bytes)
Directory table size 153 bytes (0.15 Kbytes)
58.40% of uncompressed directory table size (262 bytes)
Number of duplicate files found 1
Number of inodes 12
Number of files 6
Number of fragments 1
Number of symbolic links 0
Number of device nodes 0
Number of fifo nodes 0
Number of socket nodes 0
Number of directories 6
Number of ids (unique uids + gids) 1
Number of uids 1
maanya-goenka (1000)
Number of gids 1
maanya-goenka (1000)
maanya-goenka@debian:~/systemd (img-support)$ sudo build/systemd-analyze verify --image=run.raw testrun.service
/tmp/.#systemd-analyzec71c7297a936b91c/usr/lib/systemd/system/testrun.service:2: Unknown key name 'foo' in section 'Unit', ignoring.
testrun.service: Failed to create testrun.service/start: Unit sysinit.target not found.
The 'Unit sysinit.target not found' error that we see here is due to recursive dependency searching during
unit loading and has been addressed in a different PR:
systemd-analyze: add option to return an error value when unit verification fails #20233
-------------------------------------------------------------------------------
Example Run:
foobar.service created below is a service unit file that has a non-existing key-value
pairing (foo = bar) and is thus, syntactically invalid.
maanya-goenka@debian:~/systemd (img-support)$ cat <<EOF>img/usr/lib/systemd/system/foobar.service
> [Unit]
> foo = bar
>
> [Service]
> ExecStart = /opt/script0.sh
> EOF
The failure to create foobar.service because of the recursive dependency searching and verification has been addressed
in a different PR: systemd-analyze: add option to return an error value when unit verification fails #20233
maanya-goenka@debian:~/systemd (img-support)$ sudo build/systemd-analyze verify --root=img/ foobar.service
/home/maanya-goenka/systemd/img/usr/lib/systemd/system/foobar.service:2: Unknown key name 'foo' in section 'Unit', ignoring.
foobar.service: Failed to create foobar.service/start: Unit sysinit.target not found.
In general we almost never hit those asserts in production code, so users see
them very rarely, if ever. But either way, we just need something that users
can pass to the developers.
We have quite a few of those asserts, and some have fairly nice messages, but
many are like "WTF?" or "???" or "unexpected something". The error that is
printed includes the file location, and function name. In almost all functions
there's at most one assert, so the function name alone is enough to identify
the failure for a developer. So we don't get much extra from the message, and
we might just as well drop them.
Dropping them makes our code a tiny bit smaller, and most importantly, improves
development experience by making it easy to insert such an assert in the code
without thinking how to phrase the argument.
asprintf(3) says that the pointer is "undefined" after a failed call.
In the current glibc implementation it is just NULL. In principle the
call could return a valid pointer with bad contents or something.
We have two styles of error handling: in a majority of cases we would
check the return value, but sometimes we used (void) and relied on the
pointer not being set. In practice both styles should be equivalent,
but gcc doesn't like the second one with -Wunused-result. (Though only
sometimes. E.g. on my F34 box I don't get the same warnings as in CI,
even though the compiler version is very similar and the compilation
options are the same…). It's also nice to be consistent in our code base.
So let's always use the first style of error checking.
MANAGER_TEST_RUN_MINIMAL allows to skip setting up cgroups, which we don't
really want to do in systemd-analyze. MANAGER_TEST_RUN_BASIC doesn't
actually do anything by itself anyway.
We recently started making more use of malloc_usable_size() and rely on
it (see the string_erase() story). Given that we don't really support
sytems where malloc_usable_size() cannot be trusted beyond statistics
anyway, let's go fully in and rework GREEDY_REALLOC() on top of it:
instead of passing around and maintaining the currenly allocated size
everywhere, let's just derive it automatically from
malloc_usable_size().
I am mostly after this for the simplicity this brings. It also brings
minor efficiency improvements I guess, but things become so much nicer
to look at if we can avoid these allocation size variables everywhere.
Note that the malloc_usable_size() man page says relying on it wasn't
"good programming practice", but I think it does this for reasons that
don't apply here: the greedy realloc logic specifically doesn't rely on
the returned extra size, beyond the fact that it is equal or larger than
what was requested.
(This commit was supposed to be a quick patch btw, but apparently we use
the greedy realloc stuff quite a bit across the codebase, so this ends
up touching *a*lot* of code.)
Using a enum is all nice and generic, but at this point it seems unlikely that
we'll add further build modes. But having an enum means that we need to include
the header file with the enumeration whenerever the conditional is used. I want
to use the conditional in log.h, which makes it hard to avoid circular imports.
This nicely covers the case when optarg is optional. The same parser can be
used when the option string passed to getopt_long() requires a parameter and
when it doesn't.
The error messages are made consistent.
Also fixes a log error c&p in --crash-reboot message.
I started working on this because I wanted to change how
DEFINE_TRIVIAL_CLEANUP_FUNC is defined. Even independently of that change, it's
nice to make make things more consistent and predictable.
I think this formatting was originally used because it simplified
adding new options to the help messages. However, these days, most
tools their help message end with "\nSee the %s for details.\n" so
the final line almost never has to be edited which eliminates the
benefit of the custom formatting used for printf() help messages.
Let's make things more consistent and use the same formatting for
printf() help messages that we use everywhere else.
Prompted by https://github.com/systemd/systemd/pull/18355#discussion_r567241580
This updates the "systemd-analyze syscall-filter" command to show a
special section of syscalls that are included in @known but in no other
group. Typically this should show syscalls we either should add to any
of the existing groups or where we unsure were they best fit in.
Right now, it mostly shows arch-specific compat syscalls, we probably
should move "@obsolete". This patch doesn't add thta however.
The concept is flawed, and mostly useless. Let's finally remove it.
It has been deprecated since 90a2ec10f2 (6
years ago) and we started to warn since
55dadc5c57 (1.5 years ago).
Let's get rid of it altogether.
This information was already available in the debug output, but I think it
is good to include it in the message in the table. This makes it easier to wrap
one's head around the allowlist/denylist filtering.
https://tools.ietf.org/html/draft-knodel-terminology-02https://lwn.net/Articles/823224/
This gets rid of most but not occasions of these loaded terms:
1. scsi_id and friends are something that is supposed to be removed from
our tree (see #7594)
2. The test suite defines an API used by the ubuntu CI. We can remove
this too later, but this needs to be done in sync with the ubuntu CI.
3. In some cases the terms are part of APIs we call or where we expose
concepts the kernel names the way it names them. (In particular all
remaining uses of the word "slave" in our codebase are like this,
it's used by the POSIX PTY layer, by the network subsystem, the mount
API and the block device subsystem). Getting rid of the term in these
contexts would mean doing some major fixes of the kernel ABI first.
Regarding the replacements: when whitelist/blacklist is used as noun we
replace with with allow list/deny list, and when used as verb with
allow-list/deny-list.
Presently, CLI utilities such as systemctl will check whether they have a tty
attached or not to decide whether to parse /proc/cmdline or EFI variable
SystemdOptions looking for systemd.log_* entries.
But this check will be misleading if these tools are being launched by a
daemon, such as a monitoring daemon or automation service that runs in
background.
Make log handling of CLI tools uniform by never checking /proc/cmdline or EFI
variables to determine the logging level.
Furthermore, introduce a new log_setup_cli() shortcut to set up common options
used by most command-line utilities.
Upon an incoming connection for an accepting socket, we'd create a unit like
foo@0.service, then figure out that the instance name should be e.g. "0-41-0",
and then add the name foo@0-41-0.service to the unit. This obviously violates
the rule that any service needs to have a constance instance part.
So let's reverse the order: we first determine the instance name and then
create the unit with the correct name from the start.
There are two cases where we don't know the instance name:
- analyze-verify: we just do a quick check that the instance unit can be
created. So let's use a bogus instance string.
- selinux: the code wants to load the service unit to extract the ExecStart path
and query it for the selinux label. Do the same as above.
Note that in both cases it is possible that the real unit that is loaded could
be different than the one with the bogus instance value, for example if there
is a dropin for a specific instance name. We can't do much about this, since we
can't figure out the instance name in advance. The old code had the same
shortcoming.
Prompted by the discussions in #15180.
This is a bit more complex than I hoped, since for PID 1 we need to pass
in the synethetic environment block in we generate on demand.
It's easy to add, and should be pretty useful, in particular as in
AssertPathIsEncrypted= as it can be used for checking that
some path is encrypted before some service is invoked that might want to
place secure material there.
Maanya Goenka
Zbigniew Jędrzejewski-Szmek
Luca Boccassi
Lennart Poettering
Yu Watanabe
Daan De Meyer
Susant Sahani
Frantisek Sumsal
fangxiuning
Anita Zhang
Filipe Brandenburger