We currently have a convoluted and complex selection of which random
numbers to use. We can simplify this down to two functions that cover
all of our use cases:
1) Randomness for crypto: this one needs to wait until the RNG is
initialized. So it uses getrandom(0). If that's not available, it
polls on /dev/random, and then reads from /dev/urandom. This function
returns whether or not it was successful, as before.
2) Randomness for other things: this one uses getrandom(GRND_INSECURE).
If it's not available it uses getrandom(GRND_NONBLOCK). And if that
would block, then it falls back to /dev/urandom. And if /dev/urandom
isn't available, it uses the fallback code. It never fails and
doesn't return a value.
These two cases match all the uses of randomness inside of systemd.
I would prefer to make both of these return void, and get rid of the
fallback code, and simply assert in the incredibly unlikely case that
/dev/urandom doesn't exist. But Luca disagrees, so this commit attempts
to instead keep case (1) returning a return value, which all the callers
already check, and fix the fallback code in (2) to be less bad than
before.
For the less bad fallback code for (2), we now use auxval and some
timestamps, together with various counters representing the invocation,
hash it all together and provide the output. Provided that AT_RANDOM is
secure, this construction is probably okay too, though notably it
doesn't have any forward secrecy. Fortunately, it's only used by
random_bytes() and not by crypto_random_bytes().
After sending a SIGKILL to a process, the process might disappear from
`cgroup.threads` but still show up in `cgroup.procs` and still remains in the
cgroup and cause migrating new processes to `Delegate=yes` cgroups to fail with
`-EBUSY`. This is especially likely for heavyweight processes that consume more
kernel CPU time to clean up.
Fix this by only returning 0 when both `cgroup.threads` and
`cgroup.procs` are empty.
/etc/os-release existence is only enforced in --boot mode,
therefore the term "starting" (which also applies to chroot-like mode)
is substituted with "booting" in this context.
The recommendation to use machinectl login/shell instead of
trying to combine two distinct container instances seemed a
litte bit out of context and is now combined via "rather".
When we run `portablectl detach --enable --runtime`, then it triggers
`DisableUnitFilesWithFlags` DBus method and the main unit file is
removed, but its drop-ins are not. Hence, portable_detach() failed to
list existing portable units.
This makes the loop for listing portable units also accept drop-in
directories. So, all remaining drop-in directories are correctly
removed.
Before:
```
testsuite-29.sh[600]: + portablectl detach --now --runtime --enable /tmp/rootdir minimal-app0
portablectl[1391]: (Matching unit files with prefixes 'minimal-app0'.)
portablectl[1391]: Queued /org/freedesktop/systemd1/job/1812 to call StopUnit on portable service minimal-app0-foo.service.
portablectl[1391]: Removed "/run/systemd/system.attached/minimal-app0-foo.service".
portablectl[1391]: Queued /org/freedesktop/systemd1/job/1813 to call StopUnit on portable service minimal-app0.service.
portablectl[1391]: Removed "/run/systemd/system.attached/minimal-app0.service".
portablectl[1391]: Got result done/Success for job minimal-app0-foo.service
portablectl[1391]: Got result done/Success for job minimal-app0.service
portablectl[1391]: DetachImage failed: No unit files associated with '/tmp/rootdir' found attached to the system. Image not attached?
```
After:
```
testsuite-29.sh[508]: + portablectl detach --now --runtime --enable /tmp/rootdir minimal-app0
portablectl[1076]: (Matching unit files with prefixes 'minimal-app0'.)
portablectl[1076]: Queued /org/freedesktop/systemd1/job/1946 to call StopUnit on portable service minimal-app0-foo.service.
portablectl[1076]: Removed "/run/systemd/system.attached/minimal-app0-foo.service".
portablectl[1076]: Queued /org/freedesktop/systemd1/job/1947 to call StopUnit on portable service minimal-app0.service.
portablectl[1076]: Removed "/run/systemd/system.attached/minimal-app0.service".
portablectl[1076]: Removed /run/systemd/system.attached/minimal-app0.service.d/10-profile.conf.
portablectl[1076]: Removed /run/systemd/system.attached/minimal-app0.service.d/20-portable.conf.
portablectl[1076]: Removed /run/systemd/system.attached/minimal-app0.service.d.
portablectl[1076]: Removed /run/systemd/system.attached/minimal-app0-foo.service.d/10-profile.conf.
portablectl[1076]: Removed /run/systemd/system.attached/minimal-app0-foo.service.d/20-portable.conf.
portablectl[1076]: Removed /run/systemd/system.attached/minimal-app0-foo.service.d.
portablectl[1076]: Removed /run/portables/rootdir.
portablectl[1076]: Removed /run/systemd/system.attached.
```
Having this check as part of mount_can_start() is too late because
UNIT(u)->can_start() virtual method is called after checking the active
state of unit in unit_start().
We need to hold off running mount start jobs when /p/s/mountinfo monitor
is rate limited even when given mount unit is already active.
Fixes#20329
By using __extension__, we can silence pedantic errors we cannot or
do not want to fix.
This in particular silences:
- enum values being outside of int range
- variadic macros
- long long being C99
- type of bit-field ‘type’ is a GCC extension
- use of C99 bool in public header functions
Some compiler wrappers like honggfuzz pass -fno-builtin explicitly
and because of that the tests where fabs is used fail to compile
with something like
```
FAILED: test-bus-marshal
...
/usr/bin/ld: test-bus-marshal.p/src_libsystemd_sd-bus_test-bus-marshal.c.o: undefined reference to symbol 'fabs@@GLIBC_2.2.5'
/usr/bin/ld: /usr/lib64/libm.so.6: error adding symbols: DSO missing from command line
collect2: error: ld returned 1 exit status
```
Fun fact: it took honggfuzz less than a minute to discover
https://github.com/advisories/GHSA-gmc7-pqv9-966m used by
systemd to compress/descompress some stuff.
Yu Watanabe
Alexander Shopov
Frantisek Sumsal
Matthias Lisin
Jason A. Donenfeld
Zbigniew Jędrzejewski-Szmek
msizanoen1
Benjamin Franzke
Benjamin Franzke
Michal Sekletar
Jan Janssen
Evgeny Vereshchagin
Tomasz Paweł Gajc
Michael Biebl
Javkhlanbayar Khongorzul