This allows some strings constants to be deduplicated.
libsystemd-core.so + systemd are about 2k smaller.
Also tweak some messages for consistency. We used 'exec' in one place and
'execute' in all other messages.
$ diff -u <(strings -n 10 build/libsystemd.so.0.40.0.0 | sort) <(strings -n 10 build/libsystemd.so.0.40.0 | sort)
--- /proc/self/fd/11 2025-05-31 15:17:16.968761963 +0200
+++ /proc/self/fd/12 2025-05-31 15:17:16.970159823 +0200
@@ -3860,11 +3860,6 @@
Failed to fstat() journal file '%s', ignoring: %m
Failed to fstat %s: %m
Failed to get basic: %m
-Failed to get device "ACTION" property, ignoring: %m
-Failed to get device "DEVNUM" property, ignoring: %m
-Failed to get device "DISKSEQ" property, ignoring: %m
-Failed to get device "IFINDEX" property, ignoring: %m
-Failed to get device "SEQNUM" property, ignoring: %m
Failed to get device "%s" property, ignoring: %m
Failed to get inode number of pidfd for pid %i: %m
Failed to get peer's socket address, ignoring: %m
$ ls -l build/libsystemd.so.0.40.0{,.0}
-rwxr-xr-x 1 zbyszek zbyszek 7631640 May 31 15:16 build/libsystemd.so.0.40.0
-rwxr-xr-x 1 zbyszek zbyszek 7635736 May 31 15:16 build/libsystemd.so.0.40.0.0
$ size build/libsystemd.so.0.40.0{,.0}
text data bss dec hex filename
1241382 56185 3554 1301121 13da81 build/libsystemd.so.0.40.0
1241606 56185 3554 1301345 13db61 build/libsystemd.so.0.40.0.0
So the savings are ~4kB, which is more than I expected.
Here the .text section becomes smaller, but the file size doesn't change
(I guess some alignment issue). But is seems to be reasonable change to
anyway, we might get some savings in different compilations anyway.
Also improve two messages.
The path is fairly long and by embedding it in the message, we get a longer
data section in our binary. By using %s, we can make the template strings
shorter, deduplicating bytes in our binary. Those are error messages, i.e. by
definition they are only used very rarely, so it's completely fine if printf
does a bit more work when generating the message.
$ strings build/systemd-random-seed.0 | rg '/var/lib/systemd/random-seed'
/var/lib/systemd/random-seed
Failed to open /var/lib/systemd/random-seed for writing: %m
Failed to open /var/lib/systemd/random-seed for reading: %m
Failed to open /var/lib/systemd/random-seed: %m
Failed to stat() seed file /var/lib/systemd/random-seed: %m
Failed to read seed from /var/lib/systemd/random-seed: %m
Seed file /var/lib/systemd/random-seed not yet initialized, proceeding.
$ strings build/systemd-random-seed | rg '/var/lib/systemd/random-seed'
/var/lib/systemd/random-seed
$ ls -l build/systemd-random-seed{,.0}
-rwxr-xr-x 1 zbyszek zbyszek 68872 May 31 13:39 build/systemd-random-seed.0
-rwxr-xr-x 1 zbyszek zbyszek 64912 May 31 13:45 build/systemd-random-seed
That's a ~6% smaller binary!
When bootctl is called by an unprivileged user, then previously we got
```
Failed to read "/boot/EFI/systemd": Permission denied
Failed to open '/boot//loader/loader.conf': Permission denied
```
Now, with this patch, we get
```
Failed to read "/boot/EFI/systemd": Permission denied
Failed to open '/boot/loader/loader.conf': Permission denied
```
A new core was added to the test, but the loop counter was not increased
to wait for it, so the test races against systemd-coredump's processing.
This failed at least once in debci:
8015s [ 32.227813] TEST-87-AUX-UTILS-VM.sh[1038]: + coredumpctl info COREDUMP_TIMESTAMP=1679509902000000
8015s [ 32.228684] TEST-87-AUX-UTILS-VM.sh[1723]: No coredumps found.
Follow-up for 0c49e0049b
Fixes https://github.com/systemd/systemd/issues/37666
Follow-up for 728dbaeffb
and ad6ca4a612
This is inspired by #37538, see the discussion in
https://github.com/systemd/systemd/pull/37538#discussion_r2110229075.
If the user already specifies $TERM (which is actually
quite common if you look at run0), we'd needlessly invoke
the "fallback" logic and
a) possibly issue a DCS query whose result we end up simply
discarding in strv_env_merge()
b) set $COLORTERM to "truecolor" unconditionally, whereas
the explicit $TERM value might intend to disable the color output
To address this, the logic of setting fallback $TERM and friends
has been split out of build_environment(), and we'd call into it
only after all envvars have been collected.
This code seems to work quickly and nicely for a bunch of modern
terminals. Setting $TERM automatically removes an common annoyance for
users. This code will not work for all terminal emulators, but by adding
it in systemd we'll entice maintainers of those terminals to add support
for the sequences. For the terminals that don't support the sequence, we
get a bit of a slowdown of `< 1 ms`, which seems hardly noticeable. The
user can always set TERM explicitly to avoid this if upgrading to a
newer terminal emulator is not possible.
Closes https://github.com/systemd/systemd/issues/36994.
query_term_for_tty() is used in two places: in fixup_environment(),
which affects PID1 itself, and in build_environment(), which affects
spawned services. There is obviously some cost to the extra call,
but I think it's worthwhile to do it. When $TERM is set incorrectly,
basic output works OK, but then there are various annoying corner
cases. In particular, we get the support for color (or lack of it)
wrong, and when output is garbled, users are annoyed. Things like
text editors are almost certain to behave incorrectly. Testing in
test-terminal-util indicates that the time required to make a successful
query is on the order of a dozen microseconds, and an unsuccessful
query costs as much as our timeout, i.e. currently 1/3 ms. I think
this is an acceptable tradeoff.
No caching is used, because fixup_environment() is only called once,
and the other place in build_environment(), only affects services
which are connected to a tty, which is only a handful of services,
and often only started in special circumstances.
Fixes https://github.com/systemd/systemd/issues/36994.
With c960ca2be1, logind triggers uevents
for devices with uaccess tag, and waits for the events being processed
by udevd.
However, logind received not all triggered events, and might lose some
events. That causes session and user state file not updated, and many
desktop environment application handled the session and user were inactive.
This introduces one more device monitor instance which monitor events
for devices with 'uaccess' tag. Hence, all triggered events will be
recieved by logind, and session and user state file will be updated.
Follow-up for c960ca2be1.
Fixes#37579.
Two constants are described in the man page, but are not defined by a header.
The third constant is described in the kernel docs. Use explicit values to
show that those are values are defined externally.
A new core_pattern specifier was added, %F, to provide a PIDFD
to the usermode helper process referring to the crashed process.
This removes all possible race conditions, ensuring only the
crashed process gets inspected by systemd-coredump.
The check looks plausible, but when I started checking whether it needs
to be lowered for the recent changes, I realized that it doesn't make
much sense.
context_parse_iovw() is called from a few places, e.g.:
- process_socket(), where the other side controls the contents of the
message. We already do other checks on the correctness of the message
and this assert is not needed.
- gather_pid_metadata_from_argv(), which is called after
inserting MESSAGE_ID= and PRIORITY= into the array, so there is no
direct relation between _META_ARGV_MAX and the number of args in the
iovw.
- gather_pid_metadata_from_procfs(), where we insert a bazillion fields,
but without any relation to _META_ARGV_MAX.
Since we already separately check if the required stuff was set, drop this
misleading check.
The kernel provides %d which is documented as
"dump mode—same as value returned by prctl(2) PR_GET_DUMPABLE".
We already query /proc/pid/auxv for this information, but unfortunately this
check is subject to a race, because the crashed process may be replaced by an
attacker before we read this data, for example replacing a SUID process that
was killed by a signal with another process that is not SUID, tricking us into
making the coredump of the original process readable by the attacker.
With this patch, we effectively add one more check to the list of conditions
that need be satisfied if we are to make the coredump accessible to the user.
Reportedy-by: Qualys Security Advisory <qsa@qualys.com>
In principle, %d might return a value other than 0, 1, or 2 in the future.
Thus, we accept those, but emit a notice.
Zbigniew Jędrzejewski-Szmek
Lennart Poettering
Yu Watanabe
Christian Glombek
Luca Boccassi
Shubhendra Kushwaha
Luca Boccassi
Eisuke Kawashima
Jörg Behrmann
Mike Yuan
Temuri Doghonadze
Allison Karlitskaya