get_pretty_hostname() so far had semantics not in line with our usual
ones: the return parameter was actually freed before the return string
written into it, because that's what parse_env_file() does. Moreover,
when the value was not set it would return NULL but succeed.
Let's normalize this, and only fill in the return value if there's
something set, and never read from it, like we usually do with return
parameter, and in particular those named "ret_xyz".
The existing callers don't really care about the differences, but it's
nicer to normalize behaviour to minimize surprises.
This mirrors a similar check in Linux kernel 5.16
(9dcc38e2813e0cd3b195940c98b181ce6ede8f20) that raised the
RLIMIT_MEMLOCK to 8M.
This change does two things: raise the default limit for nspawn
containers (where we try to mimic closely what the kernel does), and
bump it when running on old kernels which still have the lower setting.
Fixes: #16300
See: https://lwn.net/Articles/876288/
RANDOM_BLOCK has existed for a long time, but RANDOM_ALLOW_INSECURE was
added more recently, leading to an awkward relationship between the two.
It turns out that only one, RANDOM_BLOCK, is needed.
RANDOM_BLOCK means return cryptographically secure numbers no matter
what. If it's not set, it means try to do that, but if it fails, fall
back to using unseeded randomness.
This part of falling back to unseeded randomness is the intent of
GRND_INSECURE, which is what RANDOM_ALLOW_INSECURE previously aliased.
Rather than having an additional flag for that, it makes more sense to
just use it whenever RANDOM_BLOCK is not set. This saves us the overhead
of having to open up /dev/urandom.
Additionally, when getrandom returns too little data, but not zero data,
we currently fall back to using /dev/urandom if RANDOM_BLOCK is not set.
This doesn't quite make sense, because if getrandom returned seeded data
once, then it will forever after return the same thing as whatever
/dev/urandom does. So in that case, we should just loop again.
Since there's never really a time where /dev/urandom is able to return
some easily but more with difficulty, we can also get rid of
RANDOM_EXTEND_WITH_PSEUDO. Once the RNG is initialized, bytes
should just flow normally.
This also makes RANDOM_MAY_FAIL obsolete, because the only case this ran
was where we'd fall back to /dev/urandom on old kernels and return
GRND_INSECURE bytes on new kernels. So also get rid of that flag.
Finally, since we're always able to use GRND_INSECURE on newer kernels,
and we only fall back to /dev/urandom on older kernels, also only fall
back to using RDRAND on those older kernels. There, the only reason to
have RDRAND is to avoid a kmsg entry about unseeded randomness.
The result of this commit is that we now cascade like this:
- Use getrandom(0) if RANDOM_BLOCK.
- Use getrandom(GRND_INSECURE) if !RANDOM_BLOCK.
- Use /dev/urandom if !RANDOM_BLOCK and no GRND_INSECURE support.
- Use /dev/urandom if no getrandom() support.
- Use RDRAND if we would use /dev/urandom for any of the above reasons
and RANDOM_ALLOW_RDRAND is set.
The data type off_t can be 64 on 32 bit systems if they have large
file support. Since mmap expects a size_t with 32 bits as second
argument truncation could occur. At worst these huge files could
lead to mmaps smaller than the previous check for small files.
This in turn shouldn't have a lot of impact because mmap allocates
at page size boundaries. This also made the PAGE_ALIGN call in
open_mmap unneeded. In fact it was neither in sync with other mmap
calls nor with its own munmap counterpart in error path.
If such large files are encountered, which is very unlikely in these
code paths, treat them with the same error as if they are too small.
The approach to use '''…'''.split() instead of a list of strings was initially
used when converting from automake because it allowed identical blocks of lines
to be used for both, making the conversion easier.
But over the years we have been using normal lists more and more, especially
when there were just a few filenames listed. This converts the rest.
No functional change.
The new helper combines a bunch of steps every invocation of
unsetenv_erase() did so far: getenv() + strdup() + unsetenv_erase().
Let's unify this into one helper that is harder to use incorrectly. It's
in inspired by TAKE_PTR() in a way: get the env var out and invalidate
where it was before.
Fixes regression introduced in 599be274c1
Moving the Xen check before the CPUID check, in order to handle the case where
a Xen domain is nested within a hypervisor which can be detected by via the
CPUID check, had an unintended consequence of causing Dom0 to report as a Xen
VM when it is not nested.
This patch stops further checks once it has been determined that Dom0 is not
nested within another hypervisor, meaning that the non-nested case matches its
previous logic (where it does not report as a VM).
Also, tidy the conditionals for the Xen and UML checks by removing handling of
a VIRTUALIZATION_VM_OTHER result, which has no code path.
Fixes#22511
On my local system I linked up the ESP and XBOOTLDR partitions, and
ended up with duplicate entries being listed. Try hard to detect that
and only enumerate entries in the ESP if it turns out that both dirs
have the same dev_t.
This should detect both bind mounted and symlinked cases and should make
our list output less confusing.
This effectively disables warnings about type/mode/ownership of existing
directories when recursively creating parent directories. (Or files. If there's
a file in a place we expect a directory, the code will later try to create
a file and fail. This follows the general pattern where we do (void)mkdir()
if the mkdir() is immediately followed by opening of a file.)
I was recently debugging an issue with the fstab-generator [1], and it says:
'Directory "/tmp" already exists, but has mode 0777 that is too permissive (0644 was requested), refusing.'
which is very specific but totally wrong in this context.
This output was added in 37c1d5e97d, and I still
think it is worth to do it, because if you actually *do* want the directory, if
there's something wrong, the precise error message will make it much easier to
diagnose. And we can't easily pass the information what failed up the call chain
because there are multiple things we check (ownership, permission mask, type)…
So passing a param whether to warn or not down into the library code seems like
the best solution, despite not being very elegant.
[1] https://bugzilla.redhat.com/show_bug.cgi?id=2051285
Even though ISO C11 doesn't mandate in which order the type specifiers
should appear, having `unsigned` at the beginning of each type
declaration feels more natural and, more importantly, it unbreaks
Coccinelle, which has a hard time parsing `long unsigned` and others:
```
init_defs_builtins: /usr/lib64/coccinelle/standard.h
init_defs: /home/mrc0mmand/repos/systemd/coccinelle/macros.h
HANDLING: src/shared/mount-util.c
: 1: strange type1, maybe because of weird order: long unsigned
```
Most of the codebase already "complies", so let's fix the remaining
"offenders".
Fixes a regression caused by 3008a6f21c.
Before the commit, when `mkdir_parents_internal()` is called from `mkdir_p()`,
it uses `_mkdir()` as `flag` is zero. But after the commit, `mkdir_safe_internal()`
is always used. Hence, if the path contains a symlink, it fails with -ENOTDIR.
To fix the issue, this makes `mkdir_p()` calls `mkdir_parents_internal()` with
MKDIR_FOLLOW_SYMLINK flag.
Fixes#22334.
Kernel commit dea2903719283c156b53741126228c4a1b40440f exposed (and
renamed) CIFS_MAGIC_NUMBER as CIFS_SUPER_MAGIC along with
SMB2_SUPER_MAGIC.
This fixes the following build fail on current Fedora Rawhide:
```
../src/basic/meson.build:389:8: ERROR: Problem encountered: found unknown filesystem(s) defined in kernel headers:
Filesystem found in kernel header but not in filesystems-gperf.gperf: CIFS_SUPER_MAGIC
Filesystem found in kernel header but not in filesystems-gperf.gperf: SMB2_SUPER_MAGIC
```
log_parse_environment() uses should_parse_proc_cmdline() to determine whether
it should parse settings from the kernel command line. But the checks that
should_parse_proc_cmdline() apply to the whole process, and we could get a positive
answer also when log_parse_environment() was called from one of the nss modules.
In case of nss-modules, we don't want to look at the kernel command line.
log_parse_environment_variables() that only looks at the environment variables
is split out and used in the nss modules.
Fixes#22020.
Yu Watanabe
Luca Boccassi
Lennart Poettering
Jason A. Donenfeld
Zbigniew Jędrzejewski-Szmek
Tobias Stoeckmann
Frantisek Sumsal
Richard Neill
Matija Skala
Franck Bui
Anita Zhang
Jan Janssen
Michal Koutný
Pigmy-penguin