Otherwise, systemd-homed-active.service will fail to deactivate all
homes because homectl can no longer talk to homed if dbus stops first.
As a result, /home cannot be umounted.
Doing this on systemd-homed-active.service instead works as well, but
systemd-homed will exit 1 if dbus is already shut down.
BPF LSM is cgroup unaware and it's set up is happening in core manager.
It occures that the current implementation is too restrictive and causes
pid 1 to freeze.
Instead:
* in bpf_lsm_setup set manager->restrict_fs pointer last,
so it is an indicator that the set up was successful
* check for manager->restrict_fs before applying unit options
Otherwise we might hit a window where the coredump happens before
midnight, but we check for it after midnight, which yields no results.
E.g.:
```
$ coredumpctl --no-legend --no-pager --file system.journal
Wed 2022-01-05 01:00:06 CET 359 0 0 SIGABRT journal /usr/bin/udevadm n/a
$ coredumpctl --since 23:59:55 --no-legend --no-pager --file system.journal
No coredumps found.
$ coredumpctl --since "2022-01-04 23:59:59" --no-legend --no-pager --file system.journal
Wed 2022-01-05 01:00:06 CET 359 0 0 SIGABRT journal /usr/bin/udevadm n/a
```
If the action failed, we should log about the issue, and continue.
Exiting would bring the graphical session down, which of course is not
appreciated by users.
As documented in previous commits, a non-negative return from the callback
doesn't matter, so the callback is simplified a bit.
Fixes#21991.
It was copy-pasted directly from OSS-Fuzz where it makes sense to
kind of strip binaries to get nice backtraces but when the fuzzers
are built and run locally with gdb it would be nice to have a little
bit more than that.
It was initially discovered in elfutils where I put the same flags
and was surprised when I couldn't run the fuzzer comfortably step
by step, which led to the same change there: https://github.com/google/oss-fuzz/pull/7092
:-)
Overall size change for the whole series:
$ size build/systemd-networkd{.0,}
text data bss dec hex filename
1878634 394016 36 2272686 22adae build/systemd-networkd.0
1755066 394080 36 2149182 20cb3e build/systemd-networkd
i.e. 121 kb.
Structured initialization is used a bit more.
There were two kinds of log messages: about failed size calculations and
about failed appends to the message. I "downgraded" the first type to log_debug,
and moved the latter to the caller. This way there should be at most one high-priority
message.
I also changed sizeof(<type>) to sizeof(var) — there is less chance of select-and-paste
error in the second form.
All the detailed logging is replaced by a simple "Failed to create netlink message",
which should be enough for the user in the unlikely case that this ever fails.
Markus Weippert
Zbigniew Jędrzejewski-Szmek
Julia Kartseva
Yu Watanabe
Mike Gilbert
Pigmy-penguin
Michael Biebl
Jason A. Donenfeld
Frantisek Sumsal
Daan De Meyer
Evgeny Vereshchagin