Let's define two helpers strdupa_safe() + strndupa_safe() which do the
same as their non-safe counterparts, except that they abort if called
with allocations larger than ALLOCA_MAX.
This should ensure that all our alloca() based allocations are subject
to this limit.
afaics glibc offers three alloca() based APIs: alloca() itself,
strndupa() + strdupa(). With this we have now replacements for all of
them, that take the limit into account.
Even if journald was not running, flushing the volatile journal used to work if
the journal was already flushed (ie the flushed flag
/run/systemd/journald/flushed was created).
However since commit 4f413af2a0, this behavior changed and now '--flush' fails
because it tries to contact journald without checking the presence of the
flushed flag anymore.
This patch restores the previous behavior since there's no reason to fail when
journalctl can figure out that the flush is not necessary.
LLVM 13 introduced `-Wunused-but-set-variable` diagnostic flag, which
trips over some intentionally set-but-not-used variables or variables
attached to cleanup handlers with side effects (`_cleanup_umask_`,
`_cleanup_(notify_on_cleanup)`, `_cleanup_(restore_sigsetp)`, etc.):
```
../src/basic/process-util.c:1257:46: error: variable 'saved_ssp' set but not used [-Werror,-Wunused-but-set-variable]
_cleanup_(restore_sigsetp) sigset_t *saved_ssp = NULL;
^
1 error generated.
```
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.
This moves the code for setting chattr file attributes appropriate for
"secrets" files from journalctl into generic chattr-util.c code so that
we can use it elsewhere.
Also, let's reuse the "bitwise" logic already implemented in the chattr
code, instead of doing it again.
We warn when the operation fails, not when it succeeds. Hence this should be
"<do>_or_<handle failure>", not "<do>_and_<handle failure>". We *could* use
whatever convention we want, but rust and perl are rather consistent in using
the logical convention. We don't care about perl that much, but having a naming
convention inverted wrt. rust would be rather confusing.
Also, pretty much every implementation does similar steps, so add a nice
wrapper which combines opening of the library and loading of the symbols.
Also add missing sentinel attribute in dlopen_or_warn().
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.)
I think quoting is more useful than not quoting. Without, arguments with
whitespace cannot be split correctly.
Unlike in coredump, "normal" quoting is used in those two cases. This output is
mostly for informational purposes, so the more readable quoting seems apropriate.
dbus GetProcesses:
$ busctl --user call org.freedesktop.systemd1 /org/freedesktop/systemd1/unit/run_2dr4450e1ae73944194bb6593fcfd255fbe_2eservice org.freedesktop.systemd1.Service GetProcesses
a(sus) 2
"/user.slice/user-1000.slice/user@1000.service/app.slice/run-r4450e1ae73944194bb6593fcfd255fbe.service" 131494 "/usr/bin/bash -c \"sleep 100; sleep 20\""
"/user.slice/user-1000.slice/user@1000.service/app.slice/run-r4450e1ae73944194bb6593fcfd255fbe.service" 131496 "sleep 100"
Let's enable this in all tools that intend to write to the OS images.
It's not conditionalized for now, as there already is conditionalization
in the existance or absence of the flag in the GPT partition table (and
it's opt-in), hence it should be OK to just enable this by default for
now if the flag is set.
On some conditions (particularly when mobile CPUs are going to sleep),
the posix_fallocate(), which is called when a new journal file is allocated,
can return -1 (EINTR). This is counted as a fatal error. So the journald
closes both old and journals, and simply throwing away further incoming
events, because of no log files open.
Introduce posix_fallocate_loop() that restarts the function in the case
of EINTR. Also let's make code base more uniform by returning negative
values on error.
Fix assert in test-sigbus.c that incorrectly counted positive values as
success. After changing the function return values, that will actually work.
Fixes: #19041
Signed-off-by: Igor Zhbanov <i.zhbanov@omprussia.ru>
This PR made modification on Lennart Poettering's basis. Fix the LineMax's function failure problem.
Signed-off-by: Yangyang Shen <shenyangyang4@huawei.com>
With some versions of the compiler, the _cleanup_ attr makes it think
the variable might be freed/closed when uninitialized, even though it
cannot happen. The added cost is small enough to be worth the benefit,
and optimized builds will help reduce it even further.
This adds the same line to most of our .conf files.
Not for systemd/user.conf though, since we can't correctly display it right
now:
$ systemd-analyze cat-config --user systemd/user.conf
Option --user is not supported for cat-config right now.
For sysusers.d, tmpfiles.d, rules.d, etc, there is no single file. Maybe
we should short READMEs in /usr/lib/sysusers.d, /usr/lib/tmpfiles.d, etc.?
Inspired by #19118.
Previously, the flag did two things at once: enable support for using
generic partitions as root fs if there were only one/allow use of
partition-table-less images as root fs. And secondly, insist that there
was a rootfs, and fail if not. Let's split these two in two separate
options so that they can be used independently of each other.
There are cases where one wants to use one without the other (i.e. when
inspecting things with systemd-dissect tool it should be OK to do so
even if image has no root fs), and it's cleaner anyway.
To make sd-device properly usable for all programs we need to provide an
API for the "action" field of an event, it's one of the most relevant
ones, and it was so far missing.
This also adds sd_device_get_seqnum(), which isn't that interesting,
except for generating pretty debug output, which we use it ourselves
for.
This also makes device_new_from_stat_rdev() public, as it is truly
useful, as we can see in our own uses of it, and I think is fairly
generic to show up in the public APIs.
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.
If the cleanup function returns the appropriate type, use that to reset the
variable. For other functions (usually the foreign ones which return void), add
an explicit value to reset to.
This causes a bit of code churn, but I think it might be worth it. In a
following patch static destructors will be called from a fuzzer, and this
change allows them to be called multiple times. But I think such a change might
help with detecting unitialized code reuse too. We hit various bugs like this,
and things are more obvious when a pointer has been set to NULL.
I was worried whether this change increases text size, but it doesn't seem to:
-Dbuildtype=debug:
before "tree-wide: return NULL from freeing functions":
-rwxrwxr-x 1 zbyszek zbyszek 4117672 Feb 16 14:36 build/libsystemd.so.0.30.0*
-rwxrwxr-x 1 zbyszek zbyszek 4494520 Feb 16 15:06 build/systemd*
after "tree-wide: return NULL from freeing functions":
-rwxrwxr-x 1 zbyszek zbyszek 4117672 Feb 16 14:36 build/libsystemd.so.0.30.0*
-rwxrwxr-x 1 zbyszek zbyszek 4494576 Feb 16 15:10 build/systemd*
now:
-rwxrwxr-x 1 zbyszek zbyszek 4117672 Feb 16 14:36 build/libsystemd.so.0.30.0*
-rwxrwxr-x 1 zbyszek zbyszek 4494640 Feb 16 15:15 build/systemd*
-Dbuildtype=release:
before "tree-wide: return NULL from freeing functions":
-rwxrwxr-x 1 zbyszek zbyszek 5252256 Feb 14 14:47 build-rawhide/libsystemd.so.0.30.0*
-rwxrwxr-x 1 zbyszek zbyszek 1834184 Feb 16 15:09 build-rawhide/systemd*
after "tree-wide: return NULL from freeing functions":
-rwxrwxr-x 1 zbyszek zbyszek 5252256 Feb 14 14:47 build-rawhide/libsystemd.so.0.30.0*
-rwxrwxr-x 1 zbyszek zbyszek 1834184 Feb 16 15:10 build-rawhide/systemd*
now:
-rwxrwxr-x 1 zbyszek zbyszek 5252256 Feb 14 14:47 build-rawhide/libsystemd.so.0.30.0*
-rwxrwxr-x 1 zbyszek zbyszek 1834184 Feb 16 15:16 build-rawhide/systemd*
I would expect that the compiler would be able to elide the setting of a
variable if the variable is never used again. And this seems to be the case:
in optimized builds there is no change in size whatsoever. And the change in
size in unoptimized build is negligible.
Something strange is happening with size of libsystemd: it's bigger in
optimized builds. Something to figure out, but unrelated to this patch.
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.
Lennart Poettering
Yu Watanabe
Franck Bui
Frantisek Sumsal
Jan Janssen
Milo Turner
Zbigniew Jędrzejewski-Szmek
Jóhann B. Guðmundsson
Igor Zhbanov
Yangyang Shen
Luca Boccassi