The old code was only able to pass the value 0 for the inheritable
and ambient capability set when a non-root user was specified.
However, sometimes it is useful to run a program in its own container
with a user specification and some capabilities set. This is needed
when the capabilities cannot be provided by file capabilities (because
the file system is mounted with MS_NOSUID for additional security).
This commit introduces the option --ambient-capability and the config
file option AmbientCapability=. Both are used in a similar way to the
existing Capability= setting. It changes the inheritable and ambient
set (which is 0 by default). The code also checks that the settings
for the bounding set (as defined by Capability= and DropCapability=)
and the setting for the ambient set (as defined by AmbientCapability=)
are compatible. Otherwise, the operation would fail in any way.
Due to the current use of -1 to indicate no support for ambient
capability set the special value "all" cannot be supported.
Also, the setting of ambient capability is restricted to running a
single program in the container payload.
It's highly confusing to reference the command line parameters via
argv[] indexes. Let's clean this up, and introduce properly named local
variables that make this easier to follow.
No actualy code changes, just some renaming of variables.
In preparation for logging more mmap-cache statistics get rid of this
piecemeal stats accessor api and just have a debug log output function
for producing the stats.
Updates the one call site using these accessors, moving what that site
did into the new log function. So the output is unchanged for now,
just a trivial refactor.
The BLKID and ELFUTILS strings were present twice. Let's reaarange things so that
each times requires definition in exactly one place.
Also let's sort things a bit:
the "heavy hitters" like PAM/MAC first,
then crypto libs,
then other libs, alphabetically,
compressors,
and external compat integrations.
I think it's useful for users to group similar concepts together to some extent.
For example, when checking what compression is available, it helps a lot to have
them listed together.
FDISK is renamed to LIBFDISK to make it clear that this is about he library and
the executable.
Similar to the previous commit. All callers pass NULL. This will
ease initial nftables backend implementation (less features to cover).
Add the function parameters as local variables and let compiler
remove branches. Followup patch can remove the if (NULL) conditionals.
All users pass a NULL/0 for those, things haven't changed since 2015
when this was added originally, so remove the arguments.
THe paramters are re-added as local function variables, initalised
to NULL or 0. A followup patch can then manually remove all
if (NULL) rather than leaving dead-branch optimization to compiler.
Reason for not doing it here is to ease patch review.
Not requiring support for this will ease initial nftables backend
implementation.
In case a use-case comues up later this feature can be re-added.
After fe841414ef, broadcast address is
also compared with existing one to determine whether the address is
foregin or not. So, the address object should not contain unnecessary
information.
Fixes#17803.
Either suppress the entry entirely, or not at all. But do not suppress
the "localhost" names we recognize, leaving the ones we do not in place.
On Fedora, where "localhost4.localdomain4" is among those listed in
/etc/hosts for 127.0.0.1 we'd thus otherwise drop the "localhost" but
keep the "localhost4.localdomain4" and then on reverse lookups only
return that, which is highly confusing.
Make them rather fail than go to the network.
Previously we'd filter them on LLMNR (explicitly) and MDNS (implicitly,
because it doesn't have .local suffix), but not on DNS.
In order to make _gateway truly reliable, let's not allow it to go to
DNS either, and keep it local.
This is particular relevant, as clients can now request lookups without
local RR synthesis, where we'd rather have NXDOMAIN returned for
_gateway than have it hit the network.
Apparently 30s is a bit too long for some cases, see #5552. But not
caching SERVFAIL at all also breaks stuff, see explanation in
201d99584e.
Let's try to find some middle ground, by lowering the cache timeout to
10s. This should be ample for the problem
201d99584e attackes, but not as long as
half a miute, as #5552 complains.
Fixes: #5552
DNSSEC validation takes the system clock into account to validate
signatures. This means if we had incorrect time and the time is then
changed to the correct one we should flush out everything and
re-validate taking the new time into account.
(This logic will also trigger after system suspend, which is not bad
either, given that quite possibly we are connected to a different
network, and thus would get different DNS data, without us noticing
otherwise via link beat).
UML runs as a user-process so it can quite easily be ran inside of
another hypervisor, for instance inside a KVM instance. UML passes
through the CPUID from the host machine so in this case detect_vm
incorrectly identifies as running under KVM. So check we are running
a UML kernel first, before we check any other hypervisors.
Resolves: #17754
Signed-off-by: Christopher Obbard <chris.obbard@collabora.com>
Apparently, IF_UNICAST_IF does not influence the routing decisions done
during connect(). But SO_BINDTODEVICE/SO_BINDTOINDEX does, which however
brings a lot of other semantics with it, we are not so interested in
(i.e. it doesn't not allow packets from any other iface to us, even if
routing otherwise allows it).
Hence, let's bind to the ifindex immediately before the connect() and
unbind right after again, so that we get the semantics we want, but not
the ones we don't.
Fixes: #11935
Replaces: #12004
This fixes the following race in reconfiguring link:
1. an interface requests UUID.
2. the interface is reconfigured and link_configure() is called.
3. sd-lldp client is started on the interface (it is enabled by default).
4. networkd acquires UUID, and get_product_uuid_handler() calls
link_configure() for the link again.
5. link_lldp_rx_configure() fails to set ifindex for already running
sd-lldp client.
6. the link enters failed state.
if the source and destination file match in contents and basic file
attributes, don#t rename, but just remove source.
This is a simple way to suppress inotify events + mtime changes when
atomically updating files.
Less 568 properly shows urlified strings.
Putative NEWS entry:
* Urlification is now enabled by default even when a pager is used.
Previously it was disabled, because less would not show such markup
properly. This has been fixed in less 568.
Please either upgrade less, or use SYSTEMD_URLIFY=0 to disable the
feature.
Let's a concept of "rate limiting" to event sources: if specific event
sources fire too often in some time interval temporarily take them
offline, and take them back online once the interval passed.
This is a simple scheme of avoiding starvation of event sources if some
event source fires too often.
This introduces the new conceptual states of "offline" and "online" for
event sources: an event source is "online" only when enabled *and* not
ratelimited, and offline in all other cases. An event source that is
online hence has its fds registered in the epoll, its signals in the
signalfd and so on.
So far we used these fields to organize the earliest/latest timer event
priority queue. In a follow-up commit we want to introduce ratelimiting
to event sources, at which point we want any kind of event source to be
able to trigger time wakeups, and hence they all need to be included in
the earliest/latest prioqs. Thus, in preparation let's make this
generic.
No change in behaviour, just some shifting around of struct members from
the type-specific to the generic part.
sd_event_prepare() invokes callbacks that might drop the last user ref
on our event loop. Let's make sure we keep an explicit ref around it, so
that we won't end up with an invalid pointer. Similar in sd_event_run().
Basically, any function that is publically callable that might end up
invoking callbacks should ref the relevant objects to be protected
against callbacks destroying these objects while we still want to access
them. We did this correctly in sd_event_dispatch() and sd_event_loop(),
but these are not the only ones which are callable from the outside.
Let's move the 3rd way how cryptsetup acquires key files to
read_file_full() too.
Since load_key_file()'s raison d'etre now is just the search path logic,
let's rename the function to find_key_file().
Previously, we'd load the file with libcryptsetup's calls. Let's do that
in our own, so that we can make use of READ_FULL_FILE_CONNECT_SOCKET,
i.e. read in keys via AF_UNIX sockets, so that people can plug key
providers into our logic.
This provides functionality similar to Debian's keyscript= crypttab
option (see → #3007), as it allows key scripts to be run as socket
activated services, that have stdout connected to the activated socket.
In contrast to traditional keyscript= support this logic runs stuff out
of process however, which is beneficial, since it allows sandboxing and
similar.
Other similar variables use the binary name underscorified and upppercased
(with "_BINARY" appended in some cases to avoid ambiguity). Add "S" to follow
the same pattern for systemd-cgroups-agent.
Based on the discussion in #16715.
Commit 428a9f6f1d freed u->pids which is
problematic since the references to this unit in m->watch_pids were no more
removed when the unit was freed.
This patch makes sure to clean all this refs up before freeing u->pids by
calling unit_unwatch_all_pids().
So far we only reported major state transitions like failure to acquire
the message. Let's report the initial failure after a few timeouts in
a new event type.
The number of timeouts is hardcoded as 3, since Windows seems to be using
that. I don't think we need to make this configurable out of the box. A
reasonable default may be enough.
They are not really boolean, because we have both ipv4 and ipv6, but
for each protocol we have either unset, no, and yes.
From https://github.com/systemd/systemd/issues/13316#issuecomment-582906817:
LinkLocalAddressing must be a boolean option, at least for ipv4:
- LinkLocalAddressing=no => no LL at all.
- LinkLocalAddressing=yes + Static Address => invalid configuration, warn and
interpret as LinkLocalAddressing=no, no LL at all.
(we check that during parsing and reject)
- LinkLocalAddressing=yes + DHCP => LL process should be subordinated to the
DHCP one, an LL address must be acquired at start or after a short N
unsuccessful DHCP attemps, and must not stop DHCP to keeping trying. When a
DHCP address is acquired, drop the LL address. If the DHCP address is lost,
re-adquire a new LL address.
(next patch will move in this direction)
- LinkLocalAddressing=fallback has no reason to exist, because LL address must
always be allocated as a fallback option when using DHCP. Having both DHCP
and LL address at the same time is an RFC violation, so
LinkLocalAdressing=yes correctly implemented is already the "fallback"
behavior. The fallback option must be deprecated and if present in older
configs must be interpreted as LinkLocalAddressing=yes.
(removed)
- And for IPv6, the LinkLocalAddress option has any sense at all? IPv6-LL
address aren't required to be always set for every IPv6 enabled interface (in
this case, coexisting with static or dynamic address if any)? Shouldn't be
always =yes?
(good question)
This effectively reverts 29e81083bd. There is no
special "fallback" mode now, so the check doesn't make sense anymore.
This reverts the gist of da1921a5c3 and
0d9fca76bb (for ppc).
Quoting #17559:
> libseccomp 2.5 added socket syscall multiplexing on ppc64(el):
> https://github.com/seccomp/libseccomp/pull/229
>
> Like with i386, s390 and s390x this breaks socket argument filtering, so
> RestrictAddressFamilies doesn't work.
>
> This causes the unit test to fail:
> /* test_restrict_address_families */
> Operating on architecture: ppc
> Failed to install socket family rules for architecture ppc, skipping: Operation canceled
> Operating on architecture: ppc64
> Failed to add socket() rule for architecture ppc64, skipping: Invalid argument
> Operating on architecture: ppc64-le
> Failed to add socket() rule for architecture ppc64-le, skipping: Invalid argument
> Assertion 'fd < 0' failed at src/test/test-seccomp.c:424, function test_restrict_address_families(). Aborting.
>
> The socket filters can't be added so `socket(AF_UNIX, SOCK_DGRAM, 0);` still
> works, triggering the assertion.
Fixes#17559.
This test assumes capability_list_length() is an invalid cap number,
but that isn't true if the running kernel supports more caps than we were
compiled with, which results in the test failing.
Instead use cap_last_cap() + 1.
If cap_last_cap() is 63, there are no more 'invalid' cap numbers to test with,
so the invalid cap number test part is skipped.
In many cases the tables are largely the same, hence define a common set
of macros to generate the common parts.
This adds in a couple of missing specifiers here and there, so is more
thant just refactoring: it actually fixes accidental omissions.
Note that some entries that look like they could be unified under these
macros can't really be unified, since they are slightly different. For
example in the DNSSD service logic we want to use the DNSSD hostname for
%H rather than the unmodified kernel one.
If /sys/class/OOO node is created and destroyed during booting (kernle driver initialization fails),
systemd-udev-trigger.service fails due to race condition.
***** race condition ***********************************************************************************
1. kernel driver create /sys/class/OOO
2. systemd-udev-trigger.service execues "/usr/bin/udevadm trigger --type=devices --action=add"
3. device_enumerator_scan_devices() => enumerator_scan_devices_all() => enumerator_scan_dir("class") =>
opendir("/sys/class") and iterate all subdirs ==> enumerator_scan_dir_and_add_devices("/sys/class/OOO")
4. kernel driver fails and destroy /sys/class/OOO
5. enumerator_scan_dir_and_add_devices("/sys/class/OOO") fails in opendir("/sys/class/OOO")
6. "systemd-udev-trigger.service" fails
7. udev coldplug fails and some device units not ready
8. mount units asociated with device units fail
9. local-fs.target fails
10. enters emergency mode
********************************************************************************************************
***** status of systemd-udev-trigger.service unit ******************************************************
$ systemctl status systemd-udev-trigger.service
systemd-udev-trigger.service - udev Coldplug all Devices
Loaded: loaded (/usr/lib/systemd/system/systemd-udev-trigger.service; static; vendor preset: enabled)
Active: failed (Result: exit-code) since Thu 2020-01-02 13:16:54 KST; 22min ago
Docs: man:udev(7)
man:systemd-udevd.service(8)
Process: 2162 ExecStart=/usr/bin/udevadm trigger --type=subsystems --action=add (code=exited, status=0/SUCCESS)
Process: 2554 ExecStart=/usr/bin/udevadm trigger --type=devices --action=add (code=exited, status=1/FAILURE)
Main PID: 2554 (code=exited, status=1/FAILURE)
Jan 02 13:16:54 localhost udevadm[2554]: Failed to scan devices: No such file or directory
Jan 02 13:16:54 localhost systemd[1]: systemd-udev-trigger.service: Main process exited, code=exited, status=1/FAILURE
Jan 02 13:16:54 localhost systemd[1]: systemd-udev-trigger.service: Failed with result 'exit-code'.
Jan 02 13:16:54 localhost systemd[1]: Failed to start udev Coldplug all Devices.
*******************************************************************************************************
***** journal log with Environment=SYSTEMD_LOG_LEVEL=debug in systemd-udev-trigger.service ***********
Jan 01 21:57:20 localhost udevadm[2039]: sd-device-enumerator: Scanning /sys/bus
Jan 01 21:57:20 localhost udevadm[2522]: sd-device-enumerator: Scan all dirs
Jan 01 21:57:20 localhost udevadm[2522]: sd-device-enumerator: Scanning /sys/bus
Jan 01 21:57:21 localhost udevadm[2522]: sd-device-enumerator: Scanning /sys/class
Jan 01 21:57:21 localhost udevadm[2522]: sd-device-enumerator: Failed to scan /sys/class: No such file or directory
Jan 01 21:57:21 localhost udevadm[2522]: Failed to scan devices: No such file or directory
*******************************************************************************************************
Follow-up for 1cdbff1c84.
After the commit 1cdbff1c84, each entry .conf contains
redundant slash like the following:
```
$ cat xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx-5.9.8-200.fc33.x86_64.conf
title Fedora 33 (Thirty Three)
version 5.9.8-200.fc33.x86_64
machine-id xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
options root=/dev/nvme0n1p2 ro rootflags=subvol=system/fedora selinux=0 audit=0
linux //xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx/5.9.8-200.fc33.x86_64/linux
initrd //xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx/5.9.8-200.fc33.x86_64/initrd
```
Devices with multicast but without mac addresses i.e. tun devices
are not getting setuped correctly:
$ ip tuntap add mode tun dev tun0
$ ip addr show tun0
16: tun0: <NO-CARRIER,POINTOPOINT,MULTICAST,NOARP,UP> mtu 1500 qdisc fq_codel state DOWN group default qlen 500
link/none
$ cat /etc/systemd/network/tun0.network
[Match]
Name = tun0
[Network]
Address=192.168.1.1/32
$ ./systemd-networkd
tun0: DHCP6 CLIENT: Failed to set identifier: Invalid argument
tun0: Failed
Otherwise if a daemon-reload happens somewhere between the enqueue of the job
start for the scope unit and scope_start() then u->pids might be lost and none
of the processes specified by "PIDs=" will be moved into the scope cgroup.
These three syscalls are internally used by libc's memory allocation
logic, i.e. ultimately back malloc(). Allocating a bit of memory is so
basic, it should just be in the default set.
This fixes a couple of issues with asan/msan and the seccomp tests: when
asan/msan is used some additional, large memory allocations take place
in the background, and unless mmap/mmap2/brk are allowlisted these will
fail, aborting the test prematurely.
This reverts commit 34136e1503.
Having the "%H" host name specifier in a DNSSD service name template
triggers a failed assertion during name template instantiation as
specifier_dnssd_host_name expects DnssdService in its userdata
pointer but finds NULL instead.
test_oomd_cgroup_context_acquire_and_insert reads the live cgroup data used
by the unit test. Under certain conditions, the memory pressure for the cgroup
can be non-zero (although most of the time it is 0 since these tests don't
generate much pressure).
Since these values are too dependent on the state of the system, remove the
checks. The type used is always >= 0 and test-psi-util already unit tests that
PSI values are parsed correctly from files so this test is redundant anyways.
Follow-up for ac24e418d9.
The original motivation of the commit and RFE #15339 is to start dhcpv6
client in managed mode when neither M nor O flag is set in the RA.
But, previously, if the setting is set to "always", then the DHCPv6
client is always started in managed mode even if O flag is set in the
RA. Such the behavior breaks RFC 7084.
The configuration of networkd has a DHCPv6Client setting in its
[IPv6AcceptRA] section, which, according to the man page, can be
a boolean, or the special value "always". The man page states
that "true" is the default.
The default value is implemented in src/network/networkd-network.c
by setting field ipv6_accept_ra_start_dhcp6_client of network to
true. However, this field is not a boolean, but an enum type
IPv6AcceptRAStartDHCP6Client (src/network/networkd-ndisc.h).
Setting ipv6_accept_ra_start_dhcp6_client to true effectively
corresponds to the enum value IPV6_ACCEPT_RA_START_DHCP6_CLIENT_ALWAYS,
resulting in the DHCPv6Client setting having the default value
"always".
This patch changes the initialisation to the correct enum value
IPV6_ACCEPT_RA_START_DHCP6_CLIENT_YES.
This is useful for development where overwriting files out side
the configured prefix will affect the host as well as stateless
systems such as NixOS that don't let packages install to /etc but handle
configuration on their own.
Alternative to https://github.com/systemd/systemd/pull/17501
tested with:
$ mkdir inst build && cd build
$ meson \
-Dcreate-log-dirs=false \
-Dsysvrcnd-path=$(realpath ../inst)/etc/rc.d \
-Dsysvinit-path=$(realpath ../inst)/etc/init.d \
-Drootprefix=$(realpath ../inst) \
-Dinstall-sysconfdir=false \
--prefix=$(realpath ../inst) ..
$ ninja install
":" is prettier, but meson 0.56+ doesn't like it:
src/systemd/meson.build:73: DEPRECATION: ":" is not allowed in test name "cc-sd-bus.h:c", it has been replaced with "_"
src/systemd/meson.build:73: DEPRECATION: ":" is not allowed in test name "cc-sd-bus.h:c-ansi", it has been replaced with "_"
...
Fixes#17568.
With the grandparent change to move most units to app.slice,
those units would be ordered After=app.slice which doesn't make any sense.
Actually they appear earlier, before the manager is even started, and
conceputally it doesn't seem useful to put them under any slice.
... when called with a valid environment variable name. This means that
any time we call it with a fixed string, it is guaranteed to return 0.
(Also when the variable is not present in the environment block.)
Coverity in CID#1435966 was complaining that s->enabled is not "restored" in
all cases. But the code was actually correct, since it should only be
"restored" in the error paths. But let's still make this prettier by not setting
the state before all operations that may fail are done.
We need to set .enabled for the prioq reshuffling operations, so move those down.
No functional change intended.
There are downsides to using fexecve:
when fexecve is used (for normal executables), /proc/pid/status shows Name: 3,
which means that ps -C foobar doesn't work. pidof works, because it checks
/proc/self/cmdline. /proc/self/exe also shows the correct link, but requires
privileges to read. /proc/self/comm also shows "3".
I think this can be considered a kernel deficiency: when O_CLOEXEC is used, this
"3" is completely meaningless. It could be any number. The kernel should use
argv[0] instead, which at least has *some* meaning.
I think the approach with fexecve/execveat is instersting, so let's provide it
as opt-in.
For scripts, when we call fexecve(), on new kernels glibc calls execveat(),
which fails with ENOENT, and then we fall back to execve() which succeeds:
[pid 63039] execveat(3, "", ["/home/zbyszek/src/systemd/test/test-path-util/script.sh", "--version"], 0x7ffefa3633f0 /* 0 vars */, AT_EMPTY_PATH) = -1 ENOENT (No such file or directory)
[pid 63039] execve("/home/zbyszek/src/systemd/test/test-path-util/script.sh", ["/home/zbyszek/src/systemd/test/test-path-util/script.sh", "--version"], 0x7ffefa3633f0 /* 0 vars */) = 0
But on older kernels glibc (some versions?) implement a fallback which falls
into the same trap with bash $0:
[pid 13534] execve("/proc/self/fd/3", ["/home/test/systemd/test/test-path-util/script.sh", "--version"], 0x7fff84995870 /* 0 vars */) = 0
We don't want that, so let's call execveat() ourselves. Then we can do the
execve() fallback as we want.
Previously it was very likely, when multiple contenders for the symlink
appear in parallel, that algorithm would select wrong symlink (i.e. one
with lower-priority).
Now the algorithm is much more defensive and when we detect change in
set of contenders for the symlink we reevaluate the selection. Same
happens when new symlink replaces already existing symlink that points
to different device node.
Note that st_mtime member of struct stat is defined as follows,
#define st_mtime st_mtim.tv_sec
Hence we omitted checking nanosecond part of the timestamp (struct
timespec) and possibly would miss modifications that happened within the
same second.