Each dlopen_*() wrapper kept its dl handle as a file-scope
'static void *xxx_dl = NULL;' even though only the wrapper itself
ever referenced it. Move each one inside the corresponding function
so its scope matches its actual use, leaving the rest of each
translation unit free of the unused file-scope name.
In pcre2-util.c the assert(pcre2_dl) in pattern_matches_and_log()
becomes assert(sym_pcre2_match), which carries the same invariant
(pattern_compile_and_log() ran dlopen_pcre2()).
Every dlopen_xxx() helper now takes an int log_level argument. It is
passed through to dlopen_many_sym_or_warn() (which in turn propagates it
to dlopen_verbose() for the library-not-installed case), and is used by
the fallback stub when support for the library is not compiled in to
emit a "<lib> support is not compiled in." message at the caller's level.
Callers pass LOG_DEBUG when gracefully degrading, or a higher level when
the failure should surface, and no longer need to log redundantly at the
call site.
As part of this, dlopen_bpf_full() (which already took a log_level) is
merged into dlopen_bpf() rather than keeping both.
The static inline fallbacks used to live in the headers, which required
pulling log.h in from every header that declared a dlopen_xxx(). Move
them into the .c files instead: the declaration is always outside the
#if HAVE_XXX block, the impl sits outside the outer #if HAVE_XXX wrap
with its own internal #if HAVE_XXX/#else/#endif, and apparmor-util.c,
idn-util.c, libmount-util.c and pam-util.c are now always compiled so
they can host their stubs.
Switch all internal callers from the private ELF_NOTE_DLOPEN() macro to
the new public SD_ELF_NOTE_DLOPEN() API from sd-dlopen.h, and remove
the now-redundant macro definitions from dlfcn-util.h.
Signed-off-by: Christian Brauner <brauner@kernel.org>
When looking at how dlopen for various libs is implemented, I found that the
macros hide too much. I find it much easier to see what is going on if 'extern'
and '= NULL' are written explicitly. After all, we don't hide those for other
definitions, e.g. our style guide says that static variables should be
initialized with '= NULL'. With that change, it's much more obvious what is
a variable declaration and what is a variable initialization.
Use 'recommended' priority for the default compression library, to
indicate that it should be prioritized over the other ones, as it
will be used to compress journals/core files.
Also use 'recommended' for kmod, as systems will likely fail to boot
if it's missing from the initrd.
Use 'suggested' for everything else.
There is one dlopen'ed TPM library that has the name generated
at runtime (depending on the driver), so that cannot be added, as it
needs to be known at build time.
Also when we support multiple ABI versions list them all, as for the
same reason we cannot know which one will be used at build time.
$ dlopen-notes.py build/libsystemd.so.0.39.0 build/src/shared/libsystemd-shared-256.so
libarchive.so.13 suggested
libbpf.so.0 suggested
libbpf.so.1 suggested
libcryptsetup.so.12 suggested
libdw.so.1 suggested
libelf.so.1 suggested
libfido2.so.1 suggested
libgcrypt.so.20 suggested
libidn2.so.0 suggested
libip4tc.so.2 suggested
libkmod.so.2 recommended
liblz4.so.1 suggested
liblzma.so.5 suggested
libp11-kit.so.0 suggested
libpcre2-8.so.0 suggested
libpwquality.so.1 suggested
libqrencode.so.3 suggested
libqrencode.so.4 suggested
libtss2-esys.so.0 suggested
libtss2-mu.so.0 suggested
libtss2-rc.so.0 suggested
libzstd.so.1 recommended
Co-authored-by: Luca Boccassi <bluca@debian.org>
When a module is blacklisted using module_blacklist=
we shouldn't fail with 'Operation not permitted'.
Instead we check for it and skip it if this is the case.
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.
Unfortunately this needs libshared to link to libkmod. Before it was linked
into systemd-udevd, udevadm, and systemd each seperately. On most systems this
doesn't make much difference, because at least systemd would be installed, but
it might not be in small chroots. It is a small library, so I hope this is not
a big issue.