This lets the libc/xcrypt allocate as much storage area as it needs.
Should fix#16965:
testsuite-46.sh[74]: ==74==ERROR: AddressSanitizer: stack-buffer-overflow on address 0x7f3e972e1080 at pc 0x7f3e9be8deed bp 0x7ffce4f28530 sp 0x7ffce4f27ce0
testsuite-46.sh[74]: WRITE of size 131232 at 0x7f3e972e1080 thread T0
testsuite-46.sh[74]: #0 0x7f3e9be8deec (/usr/lib/clang/10.0.1/lib/linux/libclang_rt.asan-x86_64.so+0x9feec)
testsuite-46.sh[74]: #1 0x559cd05a6412 in user_record_make_hashed_password /systemd-meson-build/../build/src/home/user-record-util.c:818:21
testsuite-46.sh[74]: #2 0x559cd058fb03 in create_home /systemd-meson-build/../build/src/home/homectl.c:1112:29
testsuite-46.sh[74]: #3 0x7f3e9b5b3058 in dispatch_verb /systemd-meson-build/../build/src/shared/verbs.c:103:24
testsuite-46.sh[74]: #4 0x559cd058c101 in run /systemd-meson-build/../build/src/home/homectl.c:3325:16
testsuite-46.sh[74]: #5 0x559cd058c00a in main /systemd-meson-build/../build/src/home/homectl.c:3328:1
testsuite-46.sh[74]: #6 0x7f3e9a88b151 in __libc_start_main (/usr/lib/libc.so.6+0x28151)
testsuite-46.sh[74]: #7 0x559cd0583e7d in _start (/usr/bin/homectl+0x24e7d)
testsuite-46.sh[74]: Address 0x7f3e972e1080 is located in stack of thread T0 at offset 32896 in frame
testsuite-46.sh[74]: #0 0x559cd05a60df in user_record_make_hashed_password /systemd-meson-build/../build/src/home/user-record-util.c:789
testsuite-46.sh[74]: This frame has 6 object(s):
testsuite-46.sh[74]: [32, 40) 'priv' (line 790)
testsuite-46.sh[74]: [64, 72) 'np' (line 791)
testsuite-46.sh[74]: [96, 104) 'salt' (line 809)
testsuite-46.sh[74]: [128, 32896) 'cd' (line 810)
testsuite-46.sh[74]: [33152, 33168) '.compoundliteral' <== Memory access at offset 32896 partially underflows this variable
testsuite-46.sh[74]: [33184, 33192) 'new_array' (line 832) <== Memory access at offset 32896 partially underflows this variable
testsuite-46.sh[74]: HINT: this may be a false positive if your program uses some custom stack unwind mechanism, swapcontext or vfork
testsuite-46.sh[74]: (longjmp and C++ exceptions *are* supported)
testsuite-46.sh[74]: SUMMARY: AddressSanitizer: stack-buffer-overflow (/usr/lib/clang/10.0.1/lib/linux/libclang_rt.asan-x86_64.so+0x9feec)
It seems 'struct crypt_data' is 32896 bytes, but libclang_rt wants more, at least 33168?
Two functional changes:
- "/" is now refused. The test is adjusted.
- The trailing NUL is *not* included in the returned size for abstract size. The
comments in sockaddr_un_set_path() indicate that this is the right thing to do,
and the code in socket_address_parse() wasn't doing that.
Closes#12624.
The formatting in systemd.socket.xml is updated a bit.
Currently in_addr_port_ifindex_name_to_string() always prints the ifindex
numerically. This is not super useful since the interface numbers are
semi-random. Should we use interface names in preference?
We would set .type to a fake value. All real callers (outside of tests)
immediately overwrite .type with a proper value after calling
socket_address_parse(). So let's not set it and adjust the few places
that relied on it being set to the fake value.
socket_address_parse() is modernized to only set the output argument on
success.
We would use the return value from the tested function to decide
what to print as "expected", which is confusing when something is wrong
with the tested function.
This is useful for duplicating trees that contain hardlinks: we keep
track of potential hardlinks and try to reproduce them within the
destination tree. (We do not hardlink between source and destination!).
This is useful for trees like ostree images which heavily use hardlinks
and which are otherwise exploded into separate copies of all files when
we duplicate the trees.
Behaviour is not identical, as shown by the tests in test-strv.
The combination of EXTRACT_UNQUOTE without EXTRACT_RELAX only appears in
the test, so it doesn't seem particularly important. OTOH, the difference
in handling of squished parameters could make a difference. New behaviour
is what both bash and python do, so I think we can ignore this corner case.
This change has the following advantages:
- the duplication of code paths that do a very similar thing is removed
- extract_one_word() / strv_split_extract() return a proper error code.
This is useful information, I don't know why we forgot to add it there.
gcc doesn't like arithemetic on a pointer to a function or void*, so don't
print signedness info there. It doesn't matter anyway.
C says function pointers can be different... Though I guess our code isn't
prepared for that.
If the directory (/var/lib/private is most likely) has borked permissions, the
test will fail with a cryptic message and EXIT_STATE_DIRECTORY or similar. The
message from the child with more details gets lost somewhere. Let's avoid running
the test in that case and provide a simple error message instead.
E.g. systemd-238-12.git07f8cd5.fc28.ppc64 (which I encountered on a test machine)
has /var/lib/private with 0755.
I had to move STRV_MAKE to macro.h. There is a circular dependency between
extract-word.h, strv.h, and string-util.h that makes it hard to define the
inline function otherwise.
This is cleaner that way given that we create our own half-virtualizes
device tree, and really shouldn't pull selinux labelling and access
control into that, we can only lose, in particular as our overmounted
/sys/ actually lacks /sys/fs/selinux.
(This fixes udev test woes introduced by #16821 where suddenly the test
would fail because libselinux assumed selinux was on, but selinuxfs
wasn't actually available)
JSON strings must be utf-8-clean. We also verify this in json_parse_string()
so we would reject a message with invalid utf-8 anyway.
It would probably be slightly cheaper to detect non-conformaning strings in
serialization, but then we'd have to fail serialization. By doing this early,
we give the caller a chance to handle the error nicely.
The test is adjusted to contain a valid utf-8 string after decoding of the
utf-32 encoding in json ("विवेकख्यातिरविप्लवा हानोपायः।", something about the
cessation of ignorance).
There is little point in #defining and #undefining CAP_LAST_CAP multiple times.
The check is only done in developer mode. After all, it's not an error to
compile on a newer kernel, and we shouldn't even warn in that case.
I find this version much more readable.
Add replacement defines so that when acl/libacl.h is not available, the
ACL_{READ,WRITE,EXECUTE} constants are also defined. Those constants were
declared in the kernel headers already in 1da177e4c3f41524e886b7f1b8a0c1f,
so they should be the same pretty much everywhere.
Ideally we would like to hide all other service's credentials for all
services. That would imply for us to enable mount namespacing for all
services, which is something we cannot do, both due to compatibility
with the status quo ante, and because a number of services legitimately
should be able to install mounts in the host hierarchy.
Hence we do the second best thing, we hide the credentials automatically
for all services that opt into mount namespacing otherwise. This is
quite different from other mount sandboxing options: usually you have to
explicitly opt into each. However, given that the credentials logic is a
brand new concept we invented right here and now, and particularly
security sensitive it's OK to reverse this, and by default hide
credentials whenever we can (i.e. whenever mount namespacing is
otherwise opt-ed in to).
Long story short: if you want to hide other service's credentials, the
most basic options is to just turn on PrivateMounts= and there you go,
they should all be gone.
When removing a directory tree as unprivileged user we might encounter
files owned by us but not deletable since the containing directory might
have the "r" bit missing in its access mode. Let's try to deal with
this: optionally if we get EACCES try to set the bit and see if it works
then.
Kernel 5.8 gained a hidepid= implementation that is truly per procfs,
which allows us to mount a distinct once into every unit, with
individual hidepid= settings. Let's expose this via two new settings:
ProtectProc= (wrapping hidpid=) and ProcSubset= (wrapping subset=).
Replaces: #11670
it's not entirely clear what shall be passed via parameter and what via
struct, but these two definitely fit well with the other protect_xyz
fields, hence let's move them over.
We probably should move a lot more more fields into the structure
actuall (most? all even?).
This patch adds seccomp support to the riscv64 architecture. seccomp
support is available in the riscv64 kernel since version 5.5, and it
has just been added to the libseccomp library.
riscv64 uses generic syscalls like aarch64, so I used that architecture
as a reference to find which code has to be modified.
With this patch, the testsuite passes successfully, including the
test-seccomp test. The system boots and works fine with kernel 5.4 (i.e.
without seccomp support) and kernel 5.5 (i.e. with seccomp support). I
have also verified that the "SystemCallFilter=~socket" option prevents a
service to use the ping utility when running on kernel 5.5.
For some reason this failed in koji build on s390x:
--- command ---
16:12:46 PATH='/builddir/build/BUILD/systemd-stable-246.1/s390x-redhat-linux-gnu:/usr/bin:/bin:/usr/sbin:/sbin:/usr/local/sbin' SYSTEMD_LANGUAGE_FALLBACK_MAP='/builddir/build/BUILD/systemd-stable-246.1/src/locale/language-fallback-map' SYSTEMD_KBD_MODEL_MAP='/builddir/build/BUILD/systemd-stable-246.1/src/locale/kbd-model-map' /builddir/build/BUILD/systemd-stable-246.1/s390x-redhat-linux-gnu/test-acl-util
--- stdout ---
-rw-r-----. 1 mockbuild mock 0 Aug 7 16:12 /tmp/test-empty.7RzmEc
other::---
--- stderr ---
Assertion 'r >= 0' failed at src/test/test-acl-util.c:42, function test_add_acls_for_user(). Aborting.
The concept is flawed, and mostly useless. Let's finally remove it.
It has been deprecated since 90a2ec10f2 (6
years ago) and we started to warn since
55dadc5c57 (1.5 years ago).
Let's get rid of it altogether.
Let's make /run/host the sole place we pass stuff from host to container
in and place the "inaccessible" nodes in /run/host too.
In contrast to the previous two commits this is a minor compat break, but
not a relevant one I think. Previously the container manager would place
these nodes in /run/systemd/inaccessible/ and that's where PID 1 in the
container would try to add them too when missing. Container manager and
PID 1 in the container would thus manage the same dir together.
With this change the container manager now passes an immutable directory
to the container and leaves /run/systemd entirely untouched, and managed
exclusively by PID 1 inside the container, which is nice to have clear
separation on who manages what.
In order to make sure systemd then usses the /run/host/inaccesible/
nodes this commit changes PID 1 to look for that dir and if it exists
will symlink it to /run/systemd/inaccessible.
Now, this will work fine if new nspawn and new pid 1 in the container
work together. as then the symlink is created and the difference between
the two dirs won't matter.
For the case where an old nspawn invokes a new PID 1: in this case
things work as they always worked: the dir is managed together.
For the case where different container manager invokes a new PID 1: in
this case the nodes aren't typically passed in, and PID 1 in the
container will try to create them and will likely fail partially (though
gracefully) when trying to create char/block device nodes. THis is fine
though as there are fallbacks in place for that case.
For the case where a new nspawn invokes an old PID1: this is were the
(minor) incompatibily happens: in this case new nspawn will place the
nodes in the /run/host/inaccessible/ subdir, but the PID 1 in the
container won't look for them there. Since the nodes are also not
pre-created in /run/systed/inaccessible/ PID 1 will try to create them
there as if a different container manager sets them up. This is of
course not sexy, but is not a total loss, since as mentioned fallbacks
are in place anyway. Hence I think it's OK to accept this minor
incompatibility.
The usage in unit_get_own_mask is redundant, we only need apply
disable_mask at the end befor application, i.e. calculating enable or
target mask.
(IOW, we allow all configurations, but disabling affects effective
controls.)
Modify tests accordingly and add testing of enable mask.
This is intended as cleanup, with no effect but changing unit_dump
output.
Unprivileged test-fs-util fails on my system since /sys/dev/block is
inaccessible for unprivileged users, so let's skip encrypted path test if we
get EACCES or similar.
Follows the same pattern and features as RootImage, but allows an
arbitrary mount point under / to be specified by the user, and
multiple values - like BindPaths.
Original implementation by @topimiettinen at:
https://github.com/systemd/systemd/pull/14451
Reworked to use dissect's logic instead of bare libmount() calls
and other review comments.
Thanks Topi for the initial work to come up with and implement
this useful feature.
Given a string in the format 'one:two three four:five', returns a string
vector with each word. If the second element of the tuple is not
present, an empty string is returned in its place, so that the vector
can be processed in pairs.
[zjs: use EXTRACT_UNESCAPE_SEPARATORS instead of EXTRACT_CUNESCAPE_RELAX.
This way we do escaping exactly once and in normal strict mode.]
It is OK for some symbols to be missing. With this change, "test-nss sss" can
be used to test nss-sss without crashing.
$ build-rawhide/test-nss sss fedoraproject.org
======== sss ========
_nss_sss_gethostbyname4_r not defined
_nss_sss_gethostbyname3_r not defined
_nss_sss_gethostbyname3_r not defined
_nss_sss_gethostbyname3_r not defined
_nss_sss_gethostbyname3_r not defined
_nss_sss_gethostbyname2_r("fedoraproject.org", AF_INET) → status=NSS_STATUS_NOTFOUND
errno=0/--- h_errno=-1/Resolver internal error
_nss_sss_gethostbyname2_r("fedoraproject.org", AF_INET6) → status=NSS_STATUS_NOTFOUND
errno=0/--- h_errno=-1/Resolver internal error
_nss_sss_gethostbyname2_r("fedoraproject.org", *) → status=NSS_STATUS_UNAVAIL
errno=97/EAFNOSUPPORT h_errno=-1/Resolver internal error
_nss_sss_gethostbyname2_r("fedoraproject.org", AF_UNIX) → status=NSS_STATUS_UNAVAIL
errno=97/EAFNOSUPPORT h_errno=-1/Resolver internal error
_nss_sss_gethostbyname_r("fedoraproject.org") → status=NSS_STATUS_NOTFOUND
errno=0/--- h_errno=-1/Resolver internal error
Allows to specify mount options for RootImage.
In case of multi-partition images, the partition number can be prefixed
followed by colon. Eg:
RootImageOptions=1:ro,dev 2:nosuid nodev
In absence of a partition number, 0 is assumed.
The tests fail in Fedora's koji with a timeout. Let's just bump
the timeout:
--- stderr ---
Failed to connect to system bus: No such file or directory
-.slice: Failed to enable/disable controllers on cgroup /system.slice/kojid.service, ignoring: Permission denied
path-exists.service: Failed to create cgroup /system.slice/kojid.service/path-exists.service: Permission denied
path-exists.service: Succeeded.
-.slice: Failed to enable/disable controllers on cgroup /system.slice/kojid.service, ignoring: Permission denied
path-exists.service: Failed to create cgroup /system.slice/kojid.service/path-exists.service: Permission denied
path-exists.service: Succeeded.
path-exists.path: Succeeded.
Failed to connect to system bus: No such file or directory
-.slice: Failed to enable/disable controllers on cgroup /system.slice/kojid.service, ignoring: Permission denied
path-existsglob.service: Failed to create cgroup /system.slice/kojid.service/path-existsglob.service: Permission denied
path-existsglob.service: Succeeded.
-.slice: Failed to enable/disable controllers on cgroup /system.slice/kojid.service, ignoring: Permission denied
path-existsglob.service: Failed to create cgroup /system.slice/kojid.service/path-existsglob.service: Permission denied
path-existsglob.service: Succeeded.
path-existsglob.path: Succeeded.
Failed to connect to system bus: No such file or directory
-.slice: Failed to enable/disable controllers on cgroup /system.slice/kojid.service, ignoring: Permission denied
path-changed.service: Failed to create cgroup /system.slice/kojid.service/path-changed.service: Permission denied
path-changed.service: Succeeded.
-.slice: Failed to enable/disable controllers on cgroup /system.slice/kojid.service, ignoring: Permission denied
path-changed.service: Failed to create cgroup /system.slice/kojid.service/path-changed.service: Permission denied
path-changed.service: Succeeded.
path-changed.path: Succeeded.
Failed to connect to system bus: No such file or directory
-.slice: Failed to enable/disable controllers on cgroup /system.slice/kojid.service, ignoring: Permission denied
path-modified.service: Failed to create cgroup /system.slice/kojid.service/path-modified.service: Permission denied
path-modified.service: Succeeded.
-.slice: Failed to enable/disable controllers on cgroup /system.slice/kojid.service, ignoring: Permission denied
path-modified.service: Failed to create cgroup /system.slice/kojid.service/path-modified.service: Permission denied
path-modified.service: Succeeded.
path-modified.path: Succeeded.
Failed to connect to system bus: No such file or directory
-.slice: Failed to enable/disable controllers on cgroup /system.slice/kojid.service, ignoring: Permission denied
path-mycustomunit.service: Failed to create cgroup /system.slice/kojid.service/path-mycustomunit.service: Permission denied
path-mycustomunit.service: Succeeded.
path-unit.path: Succeeded.
Failed to connect to system bus: No such file or directory
-.slice: Failed to enable/disable controllers on cgroup /system.slice/kojid.service, ignoring: Permission denied
path-directorynotempty.service: Failed to create cgroup /system.slice/kojid.service/path-directorynotempty.service: Permission denied
path-directorynotempty.service: Succeeded.
-.slice: Failed to enable/disable controllers on cgroup /system.slice/kojid.service, ignoring: Permission denied
path-directorynotempty.service: Failed to create cgroup /system.slice/kojid.service/path-directorynotempty.service: Permission denied
path-directorynotempty.service: Failed to attach to cgroup /system.slice/kojid.service/path-directorynotempty.service: No such file or directory
path-directorynotempty.service: Failed at step CGROUP spawning /bin/true: No such file or directory
path-directorynotempty.service: Main process exited, code=exited, status=219/CGROUP
path-directorynotempty.service: Failed with result 'exit-code'.
Test timeout when testing path-directorynotempty.path
This API is a complete mess. We forgot to do a hashed comparison for duplicate
entries and we use a direct pointer comparison. For trivial_hash_ops the result
is the same. For all other case, it's not. Fixing this properly will require
auditing all the uses of set_put() and ordered_set_put(). For now, let's just
acknowledge the breakage.
We would add and remove definitions based on which colors were used by other
code. Let's just define all of them to simplify tests and allow easy comparisons
which colors look good.
The CI occasionally fail in test-path with a timeout. test-path loads
units from the filesystem, and this conceivably might take more than
the default limit of 3 s. Increase the timeout substantially to see if
this helps.
The test binary has two modes: in the default argument-less mode, it
just checks that "root" can be resolved. When invoked manually, a root
prefix and user/group names can be specified.
The test is failing in koji, and the line from printf() does not end up
in the logs for some reason. log_info() works fine, so let's just use
that here too.
Read-only /var/tmp is more likely, because it's backed by a real device. /tmp
is (by default) backed by tmpfs, but it doesn't have to be. In both cases the
same consideration applies.
If we boot with read-only /var/tmp, any unit with PrivateTmp=yes would fail
because we cannot create the subdir under /var/tmp to mount the private directory.
But many services actually don't require /var/tmp (either because they only use
it occasionally, or because they only use /tmp, or even because they don't use the
temporary directories at all, and PrivateTmp=yes is used to isolate them from
the rest of the system).
To handle both cases let's create a read-only directory under /run/systemd and
mount it as the private /tmp or /var/tmp. (Read-only to not fool the service into
dumping too much data in /run.)
$ sudo systemd-run -t -p PrivateTmp=yes bash
Running as unit: run-u14.service
Press ^] three times within 1s to disconnect TTY.
[root@workstation /]# ls -l /tmp/
total 0
[root@workstation /]# ls -l /var/tmp/
total 0
[root@workstation /]# touch /tmp/f
[root@workstation /]# touch /var/tmp/f
touch: cannot touch '/var/tmp/f': Read-only file system
This commit has more changes than I like to put in one commit, but it's touching all
the same paths so it's hard to split.
exec_runtime_make() was using the wrong cleanup function, so the directory would be
left behind on error.
We never return anything higher than 63, so using "long unsigned"
as the type only confused the reader. (We can still use "long unsigned"
and safe_atolu() to parse the kernel file.)
We would refuse to print capabilities which were didn't have a name
for. The kernel adds new capabilities from time to time, most recently
cap_bpf. 'systmectl show -p CapabilityBoundingSet ...' would fail with
"Failed to parse bus message: Invalid argument" because
capability_set_to_string_alloc() would fail with -EINVAL. So let's
print such capabilities in hexadecimal:
CapabilityBoundingSet=cap_chown cap_dac_override cap_dac_read_search
cap_fowner cap_fsetid cap_kill cap_setgid cap_setuid cap_setpcap
cap_linux_immutable cap_net_bind_service cap_net_broadcast cap_net_admin
cap_net_raw cap_ipc_lock cap_ipc_owner 0x10 0x11 0x12 0x13 0x14 0x15 0x16
0x17 0x18 0x19 0x1a ...
For symmetry, also allow capabilities that we don't know to be specified.
Fixes https://bugzilla.redhat.com/show_bug.cgi?id=1853736.
The desktop file specification allows entries like ";;;;;;", full of empty strings.
But looking at the actual list of supported keys [1], empty entries are meaningless
(unless we would allow e.g. the desktop name to be the empty string. But that doesn't
seem very useful either). So let's just simplify our life and skip any empty substrings
entirely.
This would also resolve the fuzzer case:
$ valgrind build/fuzz-xdg-desktop test/fuzz/fuzz-xdg-desktop/oss-fuzz-22812
test/fuzz/fuzz-xdg-desktop/oss-fuzz-22812... ok
==2899241== HEAP SUMMARY:
==2899241== in use at exit: 0 bytes in 0 blocks
==2899241== total heap usage: 484,385 allocs, 484,385 frees, 12,411,330 bytes allocated
↓
==2899650== HEAP SUMMARY:
==2899650== in use at exit: 0 bytes in 0 blocks
==2899650== total heap usage: 1,325 allocs, 1,325 frees, 1,463,602 bytes allocated
This partially undoes the parent commit. We follow the symlink and
if it appears to be a symlink to /dev/null, even if /dev/null is not
present, we treat it as such. The addition of creation of /dev/null
in the test is reverted.
There's some inconsistency in the what is considered a masked unit:
some places (i.e. load-fragment.c) use `null_or_empty()` while others
check if the file path is symlinked to "/dev/null". Since the latter
doesn't account for things like non-absolute symlinks to "/dev/null",
this commit switches the check for "/dev/null" to use `null_or_empty_path()`
Since bc8d57f290 mac_selinux_init() is checked and considered fatal
tree-wide.
Coverity complains about it not being checked in the test code.
Follow-up of: #16223
Fixes: CID 1429975
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.
Presently, CLI utilities such as systemctl will check whether they have a tty
attached or not to decide whether to parse /proc/cmdline or EFI variable
SystemdOptions looking for systemd.log_* entries.
But this check will be misleading if these tools are being launched by a
daemon, such as a monitoring daemon or automation service that runs in
background.
Make log handling of CLI tools uniform by never checking /proc/cmdline or EFI
variables to determine the logging level.
Furthermore, introduce a new log_setup_cli() shortcut to set up common options
used by most command-line utilities.
This combines set_ensure_allocated() with set_consume(). The cool thing is that
because we know the hash ops, we can correctly free the item if appropriate.
Similarly to set_consume(), the goal is to simplify handling of the case where
the item needs to be freed on error and if already present in the set.
It's such a common operation to allocate the set and put an item in it,
that it deserves a helper. set_ensure_put() has the same return values
as set_put().
Comes with tests!
Let's make sure $XDG_RUNTIME_DIR for the user instance and /run for the
system instance is always organized the same way: the "inaccessible"
device nodes should be placed in a subdir of either called "systemd" and
a subdir of that called "inaccessible".
This way we can emphasize the common behaviour, and only differ where
really necessary.
Follow-up for #13823
dm-verity support in dissect-image at the moment is restricted to GPT
volumes.
If the image a single-filesystem type without a partition table (eg: squashfs)
and a roothash/verity file are passed, set the verity flag and mark as
read-only.
This is a follow-up for 9f83091e3c.
Instead of reading the mtime off the configuration files after reading,
let's do so before reading, but with the fd we read the data from. This
is not only cleaner (as it allows us to save one stat()), but also has
the benefit that we'll detect changes that happen while we read the
files.
This also reworks unit file drop-ins to use the common code for
determining drop-in mtime, instead of reading system clock for that.
We would parse numbers with base prefixes as user identifiers. For example,
"0x2b3bfa0" would be interpreted as UID==45334432 and "01750" would be
interpreted as UID==1000. This parsing was used also in cases where either a
user/group name or number may be specified. This means that names like
0x2b3bfa0 would be ambiguous: they are a valid user name according to our
documented relaxed rules, but they would also be parsed as numeric uids.
This behaviour is definitely not expected by users, since tools generally only
accept decimal numbers (e.g. id, getent passwd), while other tools only accept
user names and thus will interpret such strings as user names without even
attempting to convert them to numbers (su, ssh). So let's follow suit and only
accept numbers in decimal notation. Effectively this means that we will reject
such strings as a username/uid/groupname/gid where strict mode is used, and try
to look up a user/group with such a name in relaxed mode.
Since the function changed is fairly low-level and fairly widely used, this
affects multiple tools: loginctl show-user/enable-linger/disable-linger foo',
the third argument in sysusers.d, fourth and fifth arguments in tmpfiles.d,
etc.
Fixes#15985.