network: DHCPv6 Assign delegated prefix to LAN interface

In DHCPv6-PD environment, where WAN interface requests IPv6 via DHCPv6,
receives the address as well as delegated prefixes, with LAN interfaces
serving those delegated prefixes in their router advertisement messages.
The LAN interfaces on the router themselves do not have
the IPv6 addresses assigned by networkd from the prefix it
serves on that interface. Now this patch enables it.

NEWS

@@ -1,6 +1,92 @@
 systemd System and Service Manager
 
 CHANGES WITH 246 in spe:
+
+        * The various programs included in systemd can now optionally output
+          their log messages on stderr prefixed with a timestamp, controlled by
+          the $SYSTEMD_LOG_TIME environment variable.
+
+        * A new boolean kernel command line option systemd.swap= has been
+          added, which may be used to turn off automatic activation of swap
+          devices, as listed in /etc/fstab.
+
+        * The CPUAffinity= setting in service unit files now supports a new
+          special value "numa". If used, the NUMA mask is copied into the CPU
+          affinity mask.
+
+        * The man pages for the sd-bus and sd-hwdb APIs have been completed.
+
+        * networkctl gained the new "forcerenew" command for forcing all DHCP
+          server clients to renew their lease. The interface "status" output
+          will now show numerous additional fields of information about an
+          interface. There are new "up" and "down" commands to bring specific
+          interfaces up or down.
+
+        * systemd-networkd's [IPv6Prefix] section in .network files gained a
+          new boolean setting Assign=. If enabled an address from the prefix is
+          automatically assigned to the interface.
+
+        * systemd-networkd's [Network] section gained a new setting
+          IPv6PDSubnetId= that allows explicit configuration of the preferred
+          subnet that networkd's Prefix Delegation logic assigns to an
+          interfaces.
+
+        * systemd-networkd gained support for configuring the HTB queuing
+          discipline in the [HierarchyTokenBucket] and
+          [HierarchyTokenBucketClass] sections. Similar the "pfifo" qdisc may
+          be configured in the [PFIFO] section, "GRED" in
+          [GenericRandomEarlyDetection], "SFB" in [StochasticFairBlue], "cake"
+          in [CAKE], "PIE" in [PIE], "DRR" in [DeficitRoundRobinScheduler] and
+          [DeficitRoundRobinSchedulerClass], "BFIFO" in [BFIFO],
+          "PFIFOHeadDrop" in [PFIFOHeadDrop], "PFIFOFast" in [PFIFOFast] and
+          "HHF" in [HeavyHitterFilter].
+
+        * systemd-networkd gained support for a new Termination= setting in the
+          [CAN] section for configuring the termination resistor. It also
+          gained a new ListenOnly= setting for controlling whether to only
+          listen on CAN interfaces, without interfering with traffic otherwise
+          (which is useful for debugging/monitoring CAN network
+          traffic). DataBitRate=, DataSamplePoint=, FDMode=, FDNonISO= have
+          been added to configure various CAN-FD aspects.
+
+        * .link files managed by systemd-udevd gained options RxFlowControl=,
+          TxFlowControl=, AutoNegotiationFlowControl= in the [Link] section, in
+          order to configure various flow control parameters. They also gained
+          RxMiniBufferSize= and RxJumboBufferSize= in order to configure jumbo
+          frame ring buffer sizes.
+
+        * systemd-networkd's [DHCPv6] section gained a new WithoutRA= boolean
+          setting. If enabled, DHCPv6 will be attempted right-away without
+          requiring an Router Advertisement packet suggesting it
+          first. Conversely, the [IPv6AcceptRA] gained a boolean option
+          DHCPv6Client= that may be used to turn off the DHCPv6 client even if
+          the RA packets suggest it.
+
+        * systemd-networkd's [DHCPv4] section gained a new setting UseGateway=
+          which may be used to turn off use of the gateway information provided
+          by the DHCP lease. A new FallbackLeaseLifetimeSec= setting may be
+          used to configure how to process leases that lack a lifetime option.
+
+        * systemd-networkd's [DHCPv4] and [DHCPServer] sections gained a new
+          setting SendVendorOption= allowing configuration of additional vendor
+          options to send in the DHCP requests/responses. The [DHCPv6] section
+          gained a new SendOption= setting for sending arbitrary DHCP
+          options. RequestOptions= has been added to request arbitrary options
+          from the server. UserClass= has been added to set the DHCP user class
+          field.
+
+        * systemd-networkd's [DHCPServer] section gained a new set of options
+          POP3Servers=, SMTPServers=, LPRServers= for including server
+          information about these three protocols in the DHCP lease. It also
+          gained support for including "MUD" URLs ("Manufacturer Usage
+          Description"). Support for "MUD" URLs was also added to the LLDP
+          stack, configurable in the [LLDP] section in .network files.
+
+        * systemd-resolved's DNS= configuration option now optionally accepts
+          DNS server addresses suffixed by "#" followed by a host name. If
+          used, the DNS-over-TLS certificate is validated to match the
+          specified hostname.
+
         * The fs.suid_dumpable sysctl is set to 2 / "suidsafe". This allows
           systemd-coredump to save core files for suid processes. When saving
           the core file, systemd-coredump will use the effective uid and gid of
@@ -14,6 +100,244 @@ CHANGES WITH 246 in spe:
           can now be suspended or resumed either using new systemctl verbs,
           freeze and thaw respectively, or via D-Bus.
 
+        * A new sd-path.h API has been added to libsystemd. It provides a
+          simple API for retrieving various search paths and primary
+          directories for various resources.
+
+        * The sd-bus API gained a number of convenience functions that take
+          va_list arguments rather than "...". For example, there's now
+          sd_bus_call_methodv() to match sd_bus_call_method(). Previously,
+          these were missing since the calls are convenience calls only and
+          could be put together from the more low-level functions they build
+          on.
+
+        * sd-bus vtable entries learnt a new flag SD_BUS_VTABLE_ABSOLUTE_OFFSET
+          which alters how the userdata pointer to pass to the callbacks is
+          determined. If the flag is set the offset field is converted as-is
+          into a pointer, without adding it to the object pointer the vtable is
+          associated with.
+
+        * sd-bus now exposed four new functions:
+          sd_bus_interface_name_is_valid() + sd_bus_service_name_is_valid() +
+          sd_bus_member_name_is_valid() + sd_bus_object_path_is_valid() will
+          validate strings to check if they qualify as various D-Bus concepts.
+
+        * systemctl gained a new "-P" switch that is a shortcut for "--value
+          --property=…".
+
+        * The expectations on user/group name syntax are now documented in
+          detail; documentation how classic home directories may be converted
+          into home directories managed by homed has been added; documentation
+          regarding integration of homed/userdb functionality in desktops has
+          been added:
+
+              https://systemd.io/USER_NAMES
+              https://systemd.io/CONVERTING_TO_HOMED
+              https://systemd.io/USERDB_AND_DESKTOPS
+
+        * systemd-run gained a new switch --slice-inherit. If specified the
+          unit it generates is placed in the same slice as the systemd-run
+          process itself.
+
+        * service unit files now accept a new setting CoredumpFilter= which
+          allows configuration of the memory sections coredumps of the
+          service's processes shall include.
+
+        * coredumpctl gained a new --file= switch, matching the same one in
+          journalctl: a specific journal file may be specified to read the
+          coredump data from.
+
+        * Various D-Bus APIs of systemd daemons now have man pages that
+          document the methods, signals and properties.
+
+        * journald.conf gained a new boolean setting Audit= that may be used to
+          control whether systemd-journald will enable audit during
+          initialization.
+
+        * A new default .network file is now shipped that matches TUN/TAP
+          devices that begin with "vt-" in their name. Such interfaces will
+          have IP routing onto the host links set up automatically. This is
+          supposed to be used by VM managers to trivially acquire a network
+          interface which is fully set up for host communication, simply by
+          carefully picking an interface name to use.
+
+        * All D-Bus services shipped in systemd now implement the generic
+          LogControl1 D-Bus API which allows clients to change log level +
+          target of the service during runtime.
+
+        * systemd-nspawn's --resolv-conf= switch gained a number of new
+          supported values. Specifically, options starting with "replace-" are
+          like those prefixed "copy-" but replace any existing resolv.conf
+          file. And options ending in "-uplink" and "-stub" can now be used to
+          propagate other flavours of resolv.conf into the container (as
+          defined by systemd-resolved).
+
+        * systemd-binfmt gained a new switch --unregister for unregistering all
+          registered entries at once. This is now invoked automatically at
+          shutdown, so that binary formats registered with the "F" flag will
+          not block clean file system unmounting.
+
+        * Unit files, tmpfiles.d/ snippets, sysusers.d/ snippets and other
+          configuration files that support specifier expansion learnt six new
+          specifiers: %a resolves to the current architecture, %o/%w/%B/%W
+          resolve to the various ID fields from /etc/os-release, %l resolves to
+          the "short" hostname of the system, i.e. the kernel configured
+          hostname, truncated at the first dot.
+
+        * systemd-notify's --pid= switch gained new values: "parent", "self",
+          "auto" for controlling which PID to send to the service managing: the
+          systemd-notify process' PID, or the one of the process invoking it.
+
+        * When sending a file descriptor (fd) to the service manager to keep
+          track of, using the sd_notify() mechanism, a new parameter FDPOLL=0
+          may be specified. If passed the service manager will refrain from
+          poll()ing on the file descriptor. Traditionally (and when the
+          parameter is not specified), the service manager will poll it for
+          POLLHUP or POLLERR events, and immediately close the fds in that
+          case.
+
+        * A new call sd_notify_barrier() has been added to the sd-daemon.h
+          API. The call will block until all previously sent sd_notify()
+          messages have been processed by the service manager. This is useful
+          to remove races caused by a process already having disappeared at the
+          time a notification message is processed by the service manager,
+          making correct attribution impossible. The systemd-notify tool will
+          now make use of this call implicitly, but this can be turned off again
+          via the new --no-block switch.
+
+        * systemd-logind's Session bus object learnt a new method call
+          SetType() for temporarily updating the session type of an already
+          allocated session. This is useful for upgrading tty sessions to
+          graphical ones once a compositor is invoked.
+
+        * .mount units gained a new ReadWriteOnly= boolean option. If set the
+          it will not be attempted to mount a file system read-only if mounting
+          it read-write mode doesn't succeed. An option x-systemd.rw-only is
+          available in /etc/fstab to control the same.
+
+        * coredumps collected by systemd-coredump may now be compressed using
+          the zstd algorithm.
+
+        * journalctl's "-o cat" output mode will now show one or more journal
+          fields specified with --output-fields= instead of unconditionally
+          MESSAGE=. This is useful to retrieve a very specific set of fields
+          without any decoration.
+
+        * systemd-socket-proxy gained a new switch --exit-idle-time= for
+          configuring an exit-on-idle time.
+
+        * systemd-homed's LUKS backend gained the ability to discard empty file
+          system blocks automatically when the user logs out. This is enabled
+          by default to ensure that home directories take minimal space when
+          logged out but get full size guarantees when logged in. This may be
+          controlled with the new --luks-offline-discard= switch to homectl.
+
+        * If systemd-homed detects that /home/ is encrypted as a whole it will
+          now default to the directory or subvolume backends instead of the
+          LUKS backend, in order to avoid double encryption. The default
+          storage and file system may now be configured explicitly, too, via
+          the new /etc/systemd/homed.conf configuration file.
+
+        * when systemd-journald's log stream is broken up into multiple lines
+          because the PID of the sender changed this is indicated in the
+          generated log records via the _LINE_BREAK=pid-change field.
+
+        * systemd-networkd's .netdev files now support a new setting
+          VLANProtocol= in the [Bridge] section that allows configuration of
+          the VLAN protocol to use.
+
+        * systemd-repart's --empty= setting gained a new value "create". If
+          specified a new empty regular disk image file is created under the
+          specified name. It's size may be specified with the new --size=
+          option. The latter is also supported without the "create" mode, in
+          order to grow existing disk image files to the specified size. These
+          two new options make are useful when creating or manipulating
+          disk images instead of operating on actual block devices.
+
+        * systemd-repart drop-ins now support a new UUID= setting to control
+          the UUID to assign to a newly created partition.
+
+        * StandardError= and StandardOutput= in unit files no longer support
+          the "syslog" and "syslog-console" switches. They were long removed
+          from the documentation, but will now result in warnings when used,
+          and be converted to "journal" and "journal+console" automatically.
+
+        * systemd-networkd supports a new Group= setting in the [Link] section
+          of the .network files, to control the link group.
+
+        * Two new unit file settings
+          ConditionPathIsEncrypted=/AssertPathIsEncrypted= have been
+          added. They may be used to check whether a specific file system path
+          resides on a block device that is encrypted on the block level
+          (i.e. using dm-crypt/LUKS).
+
+        * Another pair of new settings ConditionEnvironment=/AssertEnvironment=
+          has been added that may be used for simple environment checks. This
+          is particularly useful when passing in environment variables from a
+          container manager (or from PAM in case of the systemd --user
+          instance).
+
+        * The /sys/module/kernel/parameters/crash_kexec_post_notifiers file is
+          not automatically set to "Y" at boot, in order to enable pstore
+          generation for collection with systemd-pstore.
+
+        * New kernel command line options systemd.condition-needs-update= and
+          systemd.condition-first-boot= have been added, which override the
+          result of the ConditionNeedsUpdate= and ConditionFirstBoot=
+          conditions.
+
+        * A new kernel command line option systemd.clock-usec= has been added
+          that allows setting the system clock to the specified time in µs
+          since Jan 1st, 1970 early during boot. This is in particular useful
+          in order to make test cases more reliable.
+
+        * A new kernel command line option systemd.hostname= has been added
+          that allows controlling the hostname that is initialized early during
+          boot.
+
+        * The /etc/crypttab tmp option now optionally takes an argument
+          selecting the file system to use. Moreover, the default is now
+          changed from ext2 to ext4.
+
+        * There's a new /etc/crypttab option "keyfile-erase". If specified the
+          key file listed in the same line is removed after use, regardless if
+          volume activation was successful or not. This is useful if the key
+          file is only acquired transiently at runtime and shall be erased
+          before the system continues to boot.
+
+        * There's also a new /etc/crypttab option "try-empty-password". If
+          specified, before asking the user for a password it is attempted to
+          unlock the volume with an empty password. This is useful for
+          installing encrypted images whose password shall be set on first boot
+          instead of at installation time.
+
+        * systemd-cryptsetup will now attempt to load the keys to unlock
+          volumes with automatically from files in
+          /etc/cryptsetup-keys.d/<volume>.key and
+          /run/cryptsetup-keys.d/<volume>.key, if any of these files exist.
+
+        * logind.conf gained a new RuntimeDirectoryInodesMax= setting to
+          control the inode limit for the per-user $XDG_RUNTIME_DIR tmpfs
+          instance.
+
+        * systemd-firstboot gained a new --root-password-hashed= parameter for
+          setting the root user's password as UNIX password hash. There's a new
+          --delete-root-password switch which instead of setting a password for
+          the root user, removes it so that log-in without a password is
+          permitted. There's now --force which if specified means any existing
+          configuration is overwritten by the specified settings. It also
+          gained a new --kernel-command-line= parameter which may be used to
+          set the /etc/kernel/cmdline file of an OS image.
+
+        * A new generator systemd-xdg-autostart-generator has been added. It
+          automatically generates systemd unit files from XDG autostart
+          .desktop files, and is useful for allowing systemd to manage services
+          defined that way safely and automatically.
+
+        * systemd will now log about all left-over processes remaining in a
+          unit when the unit is stopped. It will now warn about services using
+          KillMode=none, as this is generally an unsafe thing to make use of.
+
 CHANGES WITH 245:
 
         * A new tool "systemd-repart" has been added, that operates as an

TODO

@@ -48,6 +48,9 @@ Features:
 * pid1: also remove PID files of a service when the service starts, not just
   when it exits
 
+* systemd-path: add ESP and XBOOTLDR path. Add "private" runtime/state/cache dir enum,
+  mapping to $RUNTIME_DIRECTORY, $STATE_DIRECTORY and such
+
 * make "systemd-dissect" an official supported tool, i.e. move to /usr/bin/ and
   provide man page. Given that we now have a tool that can generate images like
   this, it's useful to have one that can dump contents of them, too.

catalog/systemd.catalog.in

@@ -435,3 +435,34 @@ hyphen and otherwise fully numeric.
 For further details on strict and relaxed user/group name rules, see:
 
 https://systemd.io/USER_NAMES
+
+-- 1b3bb94037f04bbf81028e135a12d293
+Subject: Failed to generate valid unit name from path '@MOUNT_POINT@'.
+Defined-By: systemd
+Support: %SUPPORT_URL%
+
+The following mount point path could not be converted into a valid .mount
+unit name:
+
+    @MOUNT_POINT@
+
+Typically this means that the path to the mount point is longer than allowed
+for valid unit names.
+
+systemd dynamically synthesizes .mount units for all mount points appearing on
+the system. For that a simple escaping algorithm is applied: the absolute path
+name is used, with all "/" characters replaced by "-" (the leading one is
+removed). Moreover, any non-alphanumeric characters (as well as any of ":",
+"-", "_", ".", "\") are replaced by "\xNN" where "NN" is the hexadecimal code
+of the character. Finally, ".mount" is suffixed. The resulting string must be
+under 256 characters in length to be a valid unit name. This restriction is
+made in order for all unit names to also be suitable as file names. If a mount
+point appears that — after escaping — is longer than this limit it cannot be
+mapped to a unit. In this case systemd will refrain from synthesizing a unit
+and cannot be used to manage the mount point. It will not appear in the service
+manager's unit table and thus also not be torn down safely and automatically at
+system shutdown.
+
+It is generally recommended to avoid such overly long mount point paths, or —
+if used anyway – manage them independently of systemd, i.e. establish them as
+well as tear them down automatically at system shutdown by other software.

docs/TRANSIENT-SETTINGS.md

@@ -429,6 +429,7 @@ Most socket unit settings are available to transient units.
 ✓ Broadcast=
 ✓ PassCredentials=
 ✓ PassSecurity=
+✓ PassPacketInfo=
 ✓ TCPCongestion=
 ✓ ReusePort=
 ✓ MessageQueueMaxMessages=

man/sd_path_lookup.xml

@@ -76,30 +76,30 @@
         <constant>SD_PATH_SEARCH_STATE_FACTORY</constant>,
         <constant>SD_PATH_SEARCH_CONFIGURATION</constant>,
 
-        <constant>SD_PATH_SYSTEMD_UTIL_DIR</constant>,
-        <constant>SD_PATH_SYSTEMD_SYSTEM_UNIT_DIR</constant>,
-        <constant>SD_PATH_SYSTEMD_SYSTEM_PRESET_DIR</constant>,
-        <constant>SD_PATH_SYSTEMD_USER_UNIT_DIR</constant>,
-        <constant>SD_PATH_SYSTEMD_USER_PRESET_DIR</constant>,
-        <constant>SD_PATH_SYSTEMD_SYSTEM_CONF_DIR</constant>,
-        <constant>SD_PATH_SYSTEMD_USER_CONF_DIR</constant>,
-        <constant>SD_PATH_SYSTEMD_SYSTEM_UNIT_PATH</constant>,
-        <constant>SD_PATH_SYSTEMD_USER_UNIT_PATH</constant>,
-        <constant>SD_PATH_SYSTEMD_SYSTEM_GENERATOR_DIR</constant>,
-        <constant>SD_PATH_SYSTEMD_USER_GENERATOR_DIR</constant>,
-        <constant>SD_PATH_SYSTEMD_SYSTEM_GENERATOR_PATH</constant>,
-        <constant>SD_PATH_SYSTEMD_USER_GENERATOR_PATH</constant>,
-        <constant>SD_PATH_SYSTEMD_SLEEP_DIR</constant>,
-        <constant>SD_PATH_SYSTEMD_SHUTDOWN_DIR</constant>,
+        <constant>SD_PATH_SYSTEMD_UTIL</constant>,
+        <constant>SD_PATH_SYSTEMD_SYSTEM_UNIT</constant>,
+        <constant>SD_PATH_SYSTEMD_SYSTEM_PRESET</constant>,
+        <constant>SD_PATH_SYSTEMD_USER_UNIT</constant>,
+        <constant>SD_PATH_SYSTEMD_USER_PRESET</constant>,
+        <constant>SD_PATH_SYSTEMD_SYSTEM_CONF</constant>,
+        <constant>SD_PATH_SYSTEMD_USER_CONF</constant>,
+        <constant>SD_PATH_SYSTEMD_SEARCH_SYSTEM_UNIT</constant>,
+        <constant>SD_PATH_SYSTEMD_SEARCH_USER_UNIT</constant>,
+        <constant>SD_PATH_SYSTEMD_SYSTEM_GENERATOR</constant>,
+        <constant>SD_PATH_SYSTEMD_USER_GENERATOR</constant>,
+        <constant>SD_PATH_SYSTEMD_SEARCH_SYSTEM_GENERATOR</constant>,
+        <constant>SD_PATH_SYSTEMD_SEARCH_USER_GENERATOR</constant>,
+        <constant>SD_PATH_SYSTEMD_SLEEP</constant>,
+        <constant>SD_PATH_SYSTEMD_SHUTDOWN</constant>,
 
-        <constant>SD_PATH_TMPFILES_DIR</constant>,
-        <constant>SD_PATH_SYSUSERS_DIR</constant>,
-        <constant>SD_PATH_SYSCTL_DIR</constant>,
-        <constant>SD_PATH_BINFMT_DIR</constant>,
-        <constant>SD_PATH_MODULES_LOAD_DIR</constant>,
-        <constant>SD_PATH_CATALOG_DIR</constant>,
+        <constant>SD_PATH_TMPFILES</constant>,
+        <constant>SD_PATH_SYSUSERS</constant>,
+        <constant>SD_PATH_SYSCTL</constant>,
+        <constant>SD_PATH_BINFMT</constant>,
+        <constant>SD_PATH_MODULES_LOAD</constant>,
+        <constant>SD_PATH_CATALOG</constant>,
 
-        <constant>SD_PATH_SYSTEMD_NETWORK_PATH</constant>,
+        <constant>SD_PATH_SYSTEMD_SEARCH_NETWORK</constant>,
 };</funcsynopsisinfo>
 
       <funcprototype>

man/systemd.network.xml

@@ -838,15 +838,17 @@
         <term><varname>ConfigureWithoutCarrier=</varname></term>
         <listitem>
           <para>Takes a boolean. Allows networkd to configure a specific link even if it has no carrier.
-          Defaults to false.
+          Defaults to false. If <option>IgnoreCarrierLoss=</option> is not explicitly set, it will
+          default to this value.
           </para>
         </listitem>
       </varlistentry>
       <varlistentry>
         <term><varname>IgnoreCarrierLoss=</varname></term>
         <listitem>
-          <para>A boolean. Allows networkd to retain both the static and dynamic configuration of the
-          interface even if its carrier is lost. Defaults to false.
+          <para>Takes a boolean. Allows networkd to retain both the static and dynamic configuration
+          of the interface even if its carrier is lost. When unset, the value specified with
+          <option>ConfigureWithoutCarrier=</option> is used.
           </para>
         </listitem>
       </varlistentry>
@@ -1779,6 +1781,15 @@
           </listitem>
         </varlistentry>
 
+        <varlistentry>
+          <term><varname>AssignAcquiredDelegatedPrefixAddress=</varname></term>
+          <listitem>
+            <para>Takes a boolean. Specifies whether to add an address from the delegated prefixes which are received
+            from the WAN interface by the <varname>IPv6PrefixDelegation=</varname>. When true (on LAN interfce), the EUI-64
+            algorithm will be used to form an interface identifier from the delegated prefixes. Defaults to true.</para>
+          </listitem>
+        </varlistentry>
+
         <varlistentry>
           <term><varname>PrefixDelegationHint=</varname></term>
           <listitem>
@@ -3299,7 +3310,10 @@ DHCP=ipv6</programlisting>
 Name=enp2s0
 
 [Network]
-IPv6PrefixDelegation=dhcpv6</programlisting>
+IPv6PrefixDelegation=dhcpv6
+
+[DHCPv6]
+AssignAcquiredDelegatedPrefixAddress=yes</programlisting>
 
       <para>This will enable IPv6 PD on the interface enp1s0 as an upstream interface where the
       DHCPv6 client is running and enp2s0 as a downstream interface where the prefix is delegated to.</para>

man/systemd.socket.xml

@@ -709,6 +709,15 @@
         Defaults to <option>false</option>.</para></listitem>
       </varlistentry>
 
+      <varlistentry>
+        <term><varname>PassPacketInfo=</varname></term>
+        <listitem><para>Takes a boolean value. This controls the <constant>IP_PKTINFO</constant>,
+        <constant>IPV6_RECVPKTINFO</constant> and <constant>NETLINK_PKTINFO</constant> socket options, which
+        enable reception of additional per-packet metadata as ancillary message, on
+        <constant>AF_INET</constant>, <constant>AF_INET6</constant> and <constant>AF_UNIX</constant> sockets.
+        Defaults to <option>false</option>.</para></listitem>
+      </varlistentry>
+
       <varlistentry>
         <term><varname>TCPCongestion=</varname></term>
         <listitem><para>Takes a string value. Controls the TCP

src/basic/missing_socket.h

@@ -62,3 +62,8 @@ struct sockaddr_vm {
 #ifndef IP_TRANSPARENT
 #define IP_TRANSPARENT 19
 #endif
+
+/* linux/sockios.h */
+#ifndef SIOCGSKNS
+#define SIOCGSKNS 0x894C
+#endif

src/basic/socket-util.c

@@ -1174,5 +1174,27 @@ ssize_t recvmsg_safe(int sockfd, struct msghdr *msg, int flags) {
         }
 
         return n;
-
+}
+
+int socket_pass_pktinfo(int fd, bool b) {
+        int af;
+        socklen_t sl = sizeof(af);
+
+        if (getsockopt(fd, SOL_SOCKET, SO_DOMAIN, &af, &sl) < 0)
+                return -errno;
+
+        switch (af) {
+
+        case AF_INET:
+                return setsockopt_int(fd, IPPROTO_IP, IP_PKTINFO, b);
+
+        case AF_INET6:
+                return setsockopt_int(fd, IPPROTO_IPV6, IPV6_RECVPKTINFO, b);
+
+        case AF_NETLINK:
+                return setsockopt_int(fd, SOL_NETLINK, NETLINK_PKTINFO, b);
+
+        default:
+                return -EAFNOSUPPORT;
+        }
 }

src/basic/socket-util.h

@@ -220,3 +220,5 @@ int socket_bind_to_ifname(int fd, const char *ifname);
 int socket_bind_to_ifindex(int fd, int ifindex);
 
 ssize_t recvmsg_safe(int sockfd, struct msghdr *msg, int flags);
+
+int socket_pass_pktinfo(int fd, bool b);

src/basic/unit-name.c

@@ -207,8 +207,9 @@ UnitType unit_name_to_type(const char *n) {
 }
 
 int unit_name_change_suffix(const char *n, const char *suffix, char **ret) {
-        char *e, *s;
+        _cleanup_free_ char *s = NULL;
         size_t a, b;
+        char *e;
 
         assert(n);
         assert(suffix);
@@ -230,8 +231,12 @@ int unit_name_change_suffix(const char *n, const char *suffix, char **ret) {
                 return -ENOMEM;
 
         strcpy(mempcpy(s, n, a), suffix);
-        *ret = s;
 
+        /* Make sure the name is still valid (i.e. didn't grow too large due to longer suffix) */
+        if (!unit_name_is_valid(s, UNIT_NAME_ANY))
+                return -EINVAL;
+
+        *ret = TAKE_PTR(s);
         return 0;
 }
 
@@ -253,8 +258,8 @@ int unit_name_build(const char *prefix, const char *instance, const char *suffix
 }
 
 int unit_name_build_from_type(const char *prefix, const char *instance, UnitType type, char **ret) {
+        _cleanup_free_ char *s = NULL;
         const char *ut;
-        char *s;
 
         assert(prefix);
         assert(type >= 0);
@@ -264,19 +269,23 @@ int unit_name_build_from_type(const char *prefix, const char *instance, UnitType
         if (!unit_prefix_is_valid(prefix))
                 return -EINVAL;
 
-        if (instance && !unit_instance_is_valid(instance))
-                return -EINVAL;
-
         ut = unit_type_to_string(type);
 
-        if (!instance)
-                s = strjoin(prefix, ".", ut);
-        else
+        if (instance) {
+                if (!unit_instance_is_valid(instance))
+                        return -EINVAL;
+
                 s = strjoin(prefix, "@", instance, ".", ut);
+        } else
+                s = strjoin(prefix, ".", ut);
         if (!s)
                 return -ENOMEM;
 
-        *ret = s;
+        /* Verify that this didn't grow too large (or otherwise is invalid) */
+        if (!unit_name_is_valid(s, instance ? UNIT_NAME_INSTANCE : UNIT_NAME_PLAIN))
+                return -EINVAL;
+
+        *ret = TAKE_PTR(s);
         return 0;
 }
 
@@ -441,8 +450,8 @@ int unit_name_path_unescape(const char *f, char **ret) {
 }
 
 int unit_name_replace_instance(const char *f, const char *i, char **ret) {
+        _cleanup_free_ char *s = NULL;
         const char *p, *e;
-        char *s;
         size_t a, b;
 
         assert(f);
@@ -466,7 +475,11 @@ int unit_name_replace_instance(const char *f, const char *i, char **ret) {
 
         strcpy(mempcpy(mempcpy(s, f, a + 1), i, b), e);
 
-        *ret = s;
+        /* Make sure the resulting name still is valid, i.e. didn't grow too large */
+        if (!unit_name_is_valid(s, UNIT_NAME_INSTANCE))
+                return -EINVAL;
+
+        *ret = TAKE_PTR(s);
         return 0;
 }
 
@@ -497,8 +510,7 @@ int unit_name_template(const char *f, char **ret) {
 }
 
 int unit_name_from_path(const char *path, const char *suffix, char **ret) {
-        _cleanup_free_ char *p = NULL;
-        char *s = NULL;
+        _cleanup_free_ char *p = NULL, *s = NULL;
         int r;
 
         assert(path);
@@ -516,7 +528,11 @@ int unit_name_from_path(const char *path, const char *suffix, char **ret) {
         if (!s)
                 return -ENOMEM;
 
-        *ret = s;
+        /* Refuse this if this got too long or for some other reason didn't result in a valid name */
+        if (!unit_name_is_valid(s, UNIT_NAME_PLAIN))
+                return -EINVAL;
+
+        *ret = TAKE_PTR(s);
         return 0;
 }
 
@@ -544,6 +560,10 @@ int unit_name_from_path_instance(const char *prefix, const char *path, const cha
         if (!s)
                 return -ENOMEM;
 
+        /* Refuse this if this got too long or for some other reason didn't result in a valid name */
+        if (!unit_name_is_valid(s, UNIT_NAME_INSTANCE))
+                return -EINVAL;
+
         *ret = s;
         return 0;
 }
@@ -597,9 +617,9 @@ static bool do_escape_mangle(const char *f, bool allow_globs, char *t) {
  *  If @allow_globs, globs characters are preserved. Otherwise, they are escaped.
  */
 int unit_name_mangle_with_suffix(const char *name, const char *operation, UnitNameMangle flags, const char *suffix, char **ret) {
-        char *s;
-        int r;
+        _cleanup_free_ char *s = NULL;
         bool mangled, suggest_escape = true;
+        int r;
 
         assert(name);
         assert(suffix);
@@ -657,7 +677,12 @@ int unit_name_mangle_with_suffix(const char *name, const char *operation, UnitNa
         if ((!(flags & UNIT_NAME_MANGLE_GLOB) || !string_is_glob(s)) && unit_name_to_type(s) < 0)
                 strcat(s, suffix);
 
-        *ret = s;
+        /* Make sure mangling didn't grow this too large (but don't do this check if globbing is allowed,
+         * since globs generally do not qualify as valid unit names) */
+        if (!FLAGS_SET(flags, UNIT_NAME_MANGLE_GLOB) && !unit_name_is_valid(s, UNIT_NAME_ANY))
+                return -EINVAL;
+
+        *ret = TAKE_PTR(s);
         return 1;
 
 good:
@@ -665,12 +690,13 @@ good:
         if (!s)
                 return -ENOMEM;
 
-        *ret = s;
+        *ret = TAKE_PTR(s);
         return 0;
 }
 
 int slice_build_parent_slice(const char *slice, char **ret) {
-        char *s, *dash;
+        _cleanup_free_ char *s = NULL;
+        char *dash;
         int r;
 
         assert(slice);
@@ -693,13 +719,11 @@ int slice_build_parent_slice(const char *slice, char **ret) {
                 strcpy(dash, ".slice");
         else {
                 r = free_and_strdup(&s, SPECIAL_ROOT_SLICE);
-                if (r < 0) {
-                        free(s);
+                if (r < 0)
                         return r;
         }
-        }
 
-        *ret = s;
+        *ret = TAKE_PTR(s);
         return 1;
 }
 

src/core/dbus-socket.c

@@ -104,6 +104,7 @@ const sd_bus_vtable bus_socket_vtable[] = {
         SD_BUS_PROPERTY("Broadcast", "b", bus_property_get_bool, offsetof(Socket, broadcast), SD_BUS_VTABLE_PROPERTY_CONST),
         SD_BUS_PROPERTY("PassCredentials", "b", bus_property_get_bool, offsetof(Socket, pass_cred), SD_BUS_VTABLE_PROPERTY_CONST),
         SD_BUS_PROPERTY("PassSecurity", "b", bus_property_get_bool, offsetof(Socket, pass_sec), SD_BUS_VTABLE_PROPERTY_CONST),
+        SD_BUS_PROPERTY("PassPacketInfo", "b", bus_property_get_bool, offsetof(Socket, pass_pktinfo), SD_BUS_VTABLE_PROPERTY_CONST),
         SD_BUS_PROPERTY("RemoveOnStop", "b", bus_property_get_bool, offsetof(Socket, remove_on_stop), SD_BUS_VTABLE_PROPERTY_CONST),
         SD_BUS_PROPERTY("Listen", "a(ss)", property_get_listen, 0, SD_BUS_VTABLE_PROPERTY_CONST),
         SD_BUS_PROPERTY("Symlinks", "as", NULL, offsetof(Socket, symlinks), SD_BUS_VTABLE_PROPERTY_CONST),
@@ -202,6 +203,9 @@ static int bus_socket_set_transient_property(
         if (streq(name, "PassSecurity"))
                 return bus_set_transient_bool(u, name, &s->pass_sec, message, flags, error);
 
+        if (streq(name, "PassPacketInfo"))
+                return bus_set_transient_bool(u, name, &s->pass_pktinfo, message, flags, error);
+
         if (streq(name, "ReusePort"))
                 return bus_set_transient_bool(u, name, &s->reuse_port, message, flags, error);
 

src/core/load-fragment-gperf.gperf.m4

@@ -396,6 +396,7 @@ Socket.Transparent,              config_parse_bool,                  0,
 Socket.Broadcast,                config_parse_bool,                  0,                             offsetof(Socket, broadcast)
 Socket.PassCredentials,          config_parse_bool,                  0,                             offsetof(Socket, pass_cred)
 Socket.PassSecurity,             config_parse_bool,                  0,                             offsetof(Socket, pass_sec)
+Socket.PassPacketInfo,           config_parse_bool,                  0,                             offsetof(Socket, pass_pktinfo)
 Socket.TCPCongestion,            config_parse_string,                0,                             offsetof(Socket, tcp_congestion)
 Socket.ReusePort,                config_parse_bool,                  0,                             offsetof(Socket, reuse_port)
 Socket.MessageQueueMaxMessages,  config_parse_long,                  0,                             offsetof(Socket, mq_maxmsg)

src/core/mount.c

@@ -1674,9 +1674,30 @@ static int mount_setup_unit(
         if (!is_path(where))
                 return 0;
 
+        /* Mount unit names have to be (like all other unit names) short enough to fit into file names. This
+         * means there's a good chance that overly long mount point paths after mangling them to look like a
+         * unit name would result in unit names we don't actually consider valid. This should be OK however
+         * as such long mount point paths should not happen on regular systems — and if they appear
+         * nonetheless they are generally synthesized by software, and thus managed by that other
+         * software. Having such long names just means you cannot use systemd to manage those specific mount
+         * points, which should be an OK restriction to make. After all we don't have to be able to manage
+         * all mount points in the world — as long as we don't choke on them when we encounter them. */
         r = unit_name_from_path(where, ".mount", &e);
-        if (r < 0)
-                return log_error_errno(r, "Failed to generate unit name from path '%s': %m", where);
+        if (r < 0) {
+                static RateLimit rate_limit = { /* Let's log about this at warning level at most once every
+                                                 * 5s. Given that we generate this whenever we read the file
+                                                 * otherwise we probably shouldn't flood the logs with
+                                                 * this */
+                        .interval = 5 * USEC_PER_SEC,
+                        .burst = 1,
+                };
+
+                return log_struct_errno(
+                                ratelimit_below(&rate_limit) ? LOG_WARNING : LOG_DEBUG, r,
+                                "MESSAGE_ID=" SD_MESSAGE_MOUNT_POINT_PATH_NOT_SUITABLE_STR,
+                                "MOUNT_POINT=%s", where,
+                                LOG_MESSAGE("Failed to generate valid unit name from path '%s', ignoring mount point: %m", where));
+        }
 
         u = manager_get_unit(m, e);
         if (u)
@@ -1686,7 +1707,7 @@ static int mount_setup_unit(
                  * by the sysadmin having called mount(8) directly. */
                 r = mount_setup_new_unit(m, e, what, where, options, fstype, &flags, &u);
         if (r < 0)
-                return log_warning_errno(r, "Failed to set up mount unit: %m");
+                return log_warning_errno(r, "Failed to set up mount unit for '%s': %m", where);
 
         /* If the mount changed properties or state, let's notify our clients */
         if (flags & (MOUNT_PROC_JUST_CHANGED|MOUNT_PROC_JUST_MOUNTED))

src/core/socket.c

@@ -635,6 +635,7 @@ static void socket_dump(Unit *u, FILE *f, const char *prefix) {
                 "%sBroadcast: %s\n"
                 "%sPassCredentials: %s\n"
                 "%sPassSecurity: %s\n"
+                "%sPassPacketInfo: %s\n"
                 "%sTCPCongestion: %s\n"
                 "%sRemoveOnStop: %s\n"
                 "%sWritable: %s\n"
@@ -654,6 +655,7 @@ static void socket_dump(Unit *u, FILE *f, const char *prefix) {
                 prefix, yes_no(s->broadcast),
                 prefix, yes_no(s->pass_cred),
                 prefix, yes_no(s->pass_sec),
+                prefix, yes_no(s->pass_pktinfo),
                 prefix, strna(s->tcp_congestion),
                 prefix, yes_no(s->remove_on_stop),
                 prefix, yes_no(s->writable),
@@ -1070,6 +1072,12 @@ static void socket_apply_socket_options(Socket *s, int fd) {
                         log_unit_warning_errno(UNIT(s), r, "SO_PASSSEC failed: %m");
         }
 
+        if (s->pass_pktinfo) {
+                r = socket_pass_pktinfo(fd, true);
+                if (r < 0)
+                        log_unit_warning_errno(UNIT(s), r, "Failed to enable packet info socket option: %m");
+        }
+
         if (s->priority >= 0) {
                 r = setsockopt_int(fd, SOL_SOCKET, SO_PRIORITY, s->priority);
                 if (r < 0)

src/core/socket.h

@@ -121,6 +121,7 @@ struct Socket {
         bool broadcast;
         bool pass_cred;
         bool pass_sec;
+        bool pass_pktinfo;
 
         /* Only for INET6 sockets: issue IPV6_V6ONLY sockopt */
         SocketAddressBindIPv6Only bind_ipv6_only;

src/core/systemd.pc.in

@@ -65,16 +65,16 @@ systemdshutdowndir=${systemd_shutdown_dir}
 tmpfiles_dir=${prefix}/lib/tmpfiles.d
 tmpfilesdir=${tmpfiles_dir}
 
-sysusers_dir=${prefix}/lib/sysusers.d
+sysusers_dir=${rootprefix}/lib/sysusers.d
 sysusersdir=${sysusers_dir}
 
-sysctl_dir=${prefix}/lib/sysctl.d
+sysctl_dir=${rootprefix}/lib/sysctl.d
 sysctldir=${sysctl_dir}
 
-binfmt_dir=${prefix}/lib/binfmt.d
+binfmt_dir=${rootprefix}/lib/binfmt.d
 binfmtdir=${binfmt_dir}
 
-modules_load_dir=${prefix}/lib/modules-load.d
+modules_load_dir=${rootprefix}/lib/modules-load.d
 modulesloaddir=${modules_load_dir}
 
 catalog_dir=${prefix}/lib/systemd/catalog

src/fuzz/fuzz-xdg-desktop.c

@@ -30,7 +30,6 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
 
         assert_se(service = xdg_autostart_service_parse_desktop(name));
         assert_se(service->name = strdup("fuzz-xdg-desktop.service"));
-        if (service)
         (void) xdg_autostart_service_generate_unit(service, tmpdir);
 
         return 0;

src/journal/sd-journal.c

@@ -45,7 +45,9 @@
 
 #define JOURNAL_FILES_RECHECK_USEC (2 * USEC_PER_SEC)
 
-#define REPLACE_VAR_MAX 256
+/* The maximum size of variable values we'll expand in catalog entries. We bind this to PATH_MAX for now, as
+ * we want to be able to show all officially valid paths at least */
+#define REPLACE_VAR_MAX PATH_MAX
 
 #define DEFAULT_DATA_THRESHOLD (64*1024)
 

src/libsystemd-network/dhcp6-internal.h

@@ -102,7 +102,7 @@ int dhcp6_option_append_vendor_class(uint8_t **buf, size_t *buflen, char **user_
 int dhcp6_option_parse(uint8_t **buf, size_t *buflen, uint16_t *optcode,
                        size_t *optlen, uint8_t **optvalue);
 int dhcp6_option_parse_status(DHCP6Option *option, size_t len);
-int dhcp6_option_parse_ia(DHCP6Option *iaoption, DHCP6IA *ia);
+int dhcp6_option_parse_ia(DHCP6Option *iaoption, DHCP6IA *ia, uint16_t *ret_status_code);
 int dhcp6_option_parse_ip6addrs(uint8_t *optval, uint16_t optlen,
                                 struct in6_addr **addrs, size_t count,
                                 size_t *allocated);

src/libsystemd-network/dhcp6-option.c

@@ -417,13 +417,13 @@ static int dhcp6_option_parse_pdprefix(DHCP6Option *option, DHCP6IA *ia,
         return 0;
 }
 
-int dhcp6_option_parse_ia(DHCP6Option *iaoption, DHCP6IA *ia) {
-        uint16_t iatype, optlen;
-        size_t i, len;
-        int r = 0, status;
-        uint16_t opt;
-        size_t iaaddr_offset;
+int dhcp6_option_parse_ia(DHCP6Option *iaoption, DHCP6IA *ia, uint16_t *ret_status_code) {
         uint32_t lt_t1, lt_t2, lt_valid = 0, lt_min = UINT32_MAX;
+        uint16_t iatype, optlen;
+        size_t iaaddr_offset;
+        int r = 0, status;
+        size_t i, len;
+        uint16_t opt;
 
         assert_return(ia, -EINVAL);
         assert_return(!ia->addresses, -EINVAL);
@@ -533,11 +533,15 @@ int dhcp6_option_parse_ia(DHCP6Option *iaoption, DHCP6IA *ia) {
                         status = dhcp6_option_parse_status(option, optlen + offsetof(DHCP6Option, data));
                         if (status < 0)
                                 return status;
+
                         if (status > 0) {
+                                if (ret_status_code)
+                                        *ret_status_code = status;
+
                                 log_dhcp6_client(client, "IA status %s",
                                                  dhcp6_message_status_to_string(status));
 
-                                return -EINVAL;
+                                return 0;
                         }
 
                         break;
@@ -581,7 +585,10 @@ int dhcp6_option_parse_ia(DHCP6Option *iaoption, DHCP6IA *ia) {
                 break;
         }
 
-        return 0;
+        if (ret_status_code)
+                *ret_status_code = 0;
+
+        return 1;
 }
 
 int dhcp6_option_parse_ip6addrs(uint8_t *optval, uint16_t optlen,

src/libsystemd-network/sd-dhcp6-client.c

@@ -998,10 +998,11 @@ static int client_parse_message(
                 size_t len,
                 sd_dhcp6_lease *lease) {
 
+        uint16_t ia_na_status = 0, ia_pd_status = 0;
         uint32_t lt_t1 = ~0, lt_t2 = ~0;
+        usec_t irt = IRT_DEFAULT;
         bool clientid = false;
         size_t pos = 0;
-        usec_t irt = IRT_DEFAULT;
         int r;
 
         assert(client);
@@ -1015,8 +1016,8 @@ static int client_parse_message(
                 DHCP6Option *option = (DHCP6Option *) &message->options[pos];
                 uint16_t optcode, optlen;
                 be32_t iaid_lease;
-                uint8_t *optval;
                 int  status;
+                uint8_t *optval;
 
                 if (len < pos + offsetof(DHCP6Option, data))
                         return -ENOBUFS;
@@ -1093,10 +1094,15 @@ static int client_parse_message(
                                 break;
                         }
 
-                        r = dhcp6_option_parse_ia(option, &lease->ia);
+                        r = dhcp6_option_parse_ia(option, &lease->ia, &ia_na_status);
                         if (r < 0 && r != -ENOMSG)
                                 return r;
 
+                        if (ia_na_status == DHCP6_STATUS_NO_ADDRS_AVAIL) {
+                                pos += offsetof(DHCP6Option, data) + optlen;
+                                continue;
+                        }
+
                         r = dhcp6_lease_get_iaid(lease, &iaid_lease);
                         if (r < 0)
                                 return r;
@@ -1121,10 +1127,15 @@ static int client_parse_message(
                                 break;
                         }
 
-                        r = dhcp6_option_parse_ia(option, &lease->pd);
+                        r = dhcp6_option_parse_ia(option, &lease->pd, &ia_pd_status);
                         if (r < 0 && r != -ENOMSG)
                                 return r;
 
+                        if (ia_pd_status == DHCP6_STATUS_NO_PREFIX_AVAIL) {
+                                pos += offsetof(DHCP6Option, data) + optlen;
+                                continue;
+                        }
+
                         r = dhcp6_lease_get_pd_iaid(lease, &iaid_lease);
                         if (r < 0)
                                 return r;
@@ -1188,6 +1199,11 @@ static int client_parse_message(
                 pos += offsetof(DHCP6Option, data) + optlen;
         }
 
+        if (ia_na_status > 0 && ia_pd_status > 0) {
+                log_dhcp6_client(client, "No IA_PD prefix or IA_NA address received. Ignoring.");
+                return -EINVAL;
+        }
+
         if (!clientid) {
                 log_dhcp6_client(client, "%s has incomplete options",
                                  dhcp6_message_type_to_string(message->type));

src/libsystemd-network/sd-ipv4ll.c

@@ -252,12 +252,14 @@ static int ipv4ll_start_internal(sd_ipv4ll *ll, bool reset_generation) {
                 return r;
         }
 
-        return 0;
+        return 1;
 }
 
 int sd_ipv4ll_start(sd_ipv4ll *ll) {
         assert_return(ll, -EINVAL);
-        assert_return(sd_ipv4ll_is_running(ll) == 0, -EBUSY);
+
+        if (sd_ipv4ll_is_running(ll))
+                return 0;
 
         return ipv4ll_start_internal(ll, true);
 }

src/libsystemd-network/test-dhcp6-client.c

@@ -247,17 +247,17 @@ static int test_option_status(sd_event *e) {
         option = (DHCP6Option *)option1;
         assert_se(sizeof(option1) == sizeof(DHCP6Option) + be16toh(option->len));
 
-        r = dhcp6_option_parse_ia(option, &ia);
-        assert_se(r == -EINVAL);
+        r = dhcp6_option_parse_ia(option, &ia, NULL);
+        assert_se(r == 0);
         assert_se(ia.addresses == NULL);
 
         option->len = htobe16(17);
-        r = dhcp6_option_parse_ia(option, &ia);
+        r = dhcp6_option_parse_ia(option, &ia, NULL);
         assert_se(r == -ENOBUFS);
         assert_se(ia.addresses == NULL);
 
         option->len = htobe16(sizeof(DHCP6Option));
-        r = dhcp6_option_parse_ia(option, &ia);
+        r = dhcp6_option_parse_ia(option, &ia, NULL);
         assert_se(r == -ENOBUFS);
         assert_se(ia.addresses == NULL);
 
@@ -265,7 +265,7 @@ static int test_option_status(sd_event *e) {
         option = (DHCP6Option *)option2;
         assert_se(sizeof(option2) == sizeof(DHCP6Option) + be16toh(option->len));
 
-        r = dhcp6_option_parse_ia(option, &ia);
+        r = dhcp6_option_parse_ia(option, &ia, NULL);
         assert_se(r >= 0);
         assert_se(ia.addresses == NULL);
 
@@ -273,7 +273,7 @@ static int test_option_status(sd_event *e) {
         option = (DHCP6Option *)option3;
         assert_se(sizeof(option3) == sizeof(DHCP6Option) + be16toh(option->len));
 
-        r = dhcp6_option_parse_ia(option, &ia);
+        r = dhcp6_option_parse_ia(option, &ia, NULL);
         assert_se(r >= 0);
         assert_se(ia.addresses != NULL);
         dhcp6_lease_free_ia(&ia);
@@ -282,8 +282,8 @@ static int test_option_status(sd_event *e) {
         option = (DHCP6Option *)option4;
         assert_se(sizeof(option4) == sizeof(DHCP6Option) + be16toh(option->len));
 
-        r = dhcp6_option_parse_ia(option, &pd);
-        assert_se(r == 0);
+        r = dhcp6_option_parse_ia(option, &pd, NULL);
+        assert_se(r >= 0);
         assert_se(pd.addresses != NULL);
         assert_se(memcmp(&pd.ia_pd.id, &option4[4], 4) == 0);
         assert_se(memcmp(&pd.ia_pd.lifetime_t1, &option4[8], 4) == 0);
@@ -294,8 +294,8 @@ static int test_option_status(sd_event *e) {
         option = (DHCP6Option *)option5;
         assert_se(sizeof(option5) == sizeof(DHCP6Option) + be16toh(option->len));
 
-        r = dhcp6_option_parse_ia(option, &pd);
-        assert_se(r == 0);
+        r = dhcp6_option_parse_ia(option, &pd, NULL);
+        assert_se(r >= 0);
         assert_se(pd.addresses != NULL);
         dhcp6_lease_free_ia(&pd);
 
@@ -364,15 +364,15 @@ static int test_advertise_option(sd_event *e) {
         _cleanup_(sd_dhcp6_lease_unrefp) sd_dhcp6_lease *lease = NULL;
         DHCP6Message *advertise = (DHCP6Message *)msg_advertise;
         size_t len = sizeof(msg_advertise) - sizeof(DHCP6Message), pos = 0;
-        be32_t val;
-        uint8_t preference = 255;
-        struct in6_addr addr;
         uint32_t lt_pref, lt_valid;
-        int r;
-        uint8_t *opt;
         bool opt_clientid = false;
         const struct in6_addr *addrs;
+        uint8_t preference = 255;
+        struct in6_addr addr;
         char **domains;
+        uint8_t *opt;
+        int r;
+        be32_t val;
 
         log_debug("/* %s */", __func__);
 
@@ -410,7 +410,7 @@ static int test_advertise_option(sd_event *e) {
                         val = htobe32(120);
                         assert_se(!memcmp(optval + 8, &val, sizeof(val)));
 
-                        assert_se(dhcp6_option_parse_ia(option, &lease->ia) >= 0);
+                        assert_se(dhcp6_option_parse_ia(option, &lease->ia, NULL) >= 0);
 
                         break;
 
@@ -563,12 +563,12 @@ static int test_client_send_reply(DHCP6Message *request) {
 
 static int test_client_verify_request(DHCP6Message *request, size_t len) {
         _cleanup_(sd_dhcp6_lease_unrefp) sd_dhcp6_lease *lease = NULL;
-        size_t pos = 0;
         bool found_clientid = false, found_iana = false, found_serverid = false,
                 found_elapsed_time = false, found_fqdn = false;
-        struct in6_addr addr;
-        be32_t val;
         uint32_t lt_pref, lt_valid;
+        struct in6_addr addr;
+        size_t pos = 0;
+        be32_t val;
 
         log_debug("/* %s */", __func__);
 
@@ -606,7 +606,7 @@ static int test_client_verify_request(DHCP6Message *request, size_t len) {
                         val = htobe32(120);
                         assert_se(!memcmp(optval + 8, &val, sizeof(val)));
 
-                        assert_se(!dhcp6_option_parse_ia(option, &lease->ia));
+                        assert_se(dhcp6_option_parse_ia(option, &lease->ia, NULL) >= 0);
 
                         break;
 

src/libsystemd-network/test-ipv4ll.c

@@ -159,10 +159,10 @@ static void test_basic_request(sd_event *e) {
         assert_se(sd_ipv4ll_start(ll) == -EINVAL);
 
         assert_se(sd_ipv4ll_set_ifindex(ll, 1) == 0);
-        assert_se(sd_ipv4ll_start(ll) == 0);
+        assert_se(sd_ipv4ll_start(ll) == 1);
 
         sd_event_run(e, (uint64_t) -1);
-        assert_se(sd_ipv4ll_start(ll) == -EBUSY);
+        assert_se(sd_ipv4ll_start(ll) == 0);
 
         assert_se(sd_ipv4ll_is_running(ll));
 

src/libsystemd-network/test-ndisc-rs.c

@@ -297,6 +297,7 @@ static void test_rs(void) {
 
         assert_se(sd_ndisc_stop(nd) >= 0);
         assert_se(sd_ndisc_start(nd) >= 0);
+        assert_se(sd_ndisc_start(nd) >= 0);
         assert_se(sd_ndisc_stop(nd) >= 0);
 
         assert_se(sd_ndisc_start(nd) >= 0);

src/libsystemd/libsystemd.sym

@@ -715,4 +715,6 @@ global:
 
         sd_path_lookup;
         sd_path_lookup_strv;
+
+        sd_notify_barrier;
 } LIBSYSTEMD_245;

src/libsystemd/sd-device/device-monitor.c

@@ -3,6 +3,8 @@
 #include <errno.h>
 #include <linux/filter.h>
 #include <linux/netlink.h>
+#include <linux/sockios.h>
+#include <sys/ioctl.h>
 #include <unistd.h>
 
 #include "sd-device.h"
@@ -13,10 +15,12 @@
 #include "device-monitor-private.h"
 #include "device-private.h"
 #include "device-util.h"
+#include "errno-util.h"
 #include "fd-util.h"
 #include "format-util.h"
 #include "hashmap.h"
 #include "io-util.h"
+#include "missing_socket.h"
 #include "mountpoint-util.h"
 #include "set.h"
 #include "socket-util.h"
@@ -163,12 +167,54 @@ int device_monitor_new_full(sd_device_monitor **ret, MonitorNetlinkGroup group,
 
         if (fd >= 0) {
                 r = monitor_set_nl_address(m);
-                if (r < 0)
-                        return log_debug_errno(r, "sd-device-monitor: Failed to set netlink address: %m");
+                if (r < 0) {
+                        log_debug_errno(r, "sd-device-monitor: Failed to set netlink address: %m");
+                        goto fail;
+                }
+        }
+
+        if (DEBUG_LOGGING) {
+                _cleanup_close_ int netns = -1;
+
+                /* So here's the thing: only AF_NETLINK sockets from the main network namespace will get
+                 * hardware events. Let's check if ours is from there, and if not generate a debug message,
+                 * since we cannot possibly work correctly otherwise. This is just a safety check to make
+                 * things easier to debug. */
+
+                netns = ioctl(m->sock, SIOCGSKNS);
+                if (netns < 0)
+                        log_debug_errno(errno, "sd-device-monitor: Unable to get network namespace of udev netlink socket, unable to determine if we are in host netns: %m");
+                else {
+                        struct stat a, b;
+
+                        if (fstat(netns, &a) < 0) {
+                                r = log_debug_errno(errno, "sd-device-monitor: Failed to stat netns of udev netlink socket: %m");
+                                goto fail;
+                        }
+
+                        if (stat("/proc/1/ns/net", &b) < 0) {
+                                if (ERRNO_IS_PRIVILEGE(errno))
+                                        /* If we can't access PID1's netns info due to permissions, it's fine, this is a
+                                         * safety check only after all. */
+                                        log_debug_errno(errno, "sd-device-monitor: No permission to stat PID1's netns, unable to determine if we are in host netns: %m");
+                                else
+                                        log_debug_errno(errno, "sd-device-monitor: Failed to stat PID1's netns: %m");
+
+                        } else if (a.st_dev != b.st_dev || a.st_ino != b.st_ino)
+                                log_debug("sd-device-monitor: Netlink socket we listen on is not from host netns, we won't see device events.");
+                }
         }
 
         *ret = TAKE_PTR(m);
         return 0;
+
+fail:
+        /* Let's unset the socket fd in the monitor object before we destroy it so that the fd passed in is
+         * not closed on failure. */
+        if (fd >= 0)
+                m->sock = -1;
+
+        return r;
 }
 
 _public_ int sd_device_monitor_new(sd_device_monitor **ret) {

src/libsystemd/sd-netlink/netlink-socket.c

@@ -16,10 +16,6 @@
 #include "socket-util.h"
 #include "util.h"
 
-/* For some reason we need some extra cmsg space on some kernels. It's not clear why, and one of those days
- * we need to track this down. See: https://github.com/systemd/systemd/pull/15457 */
-#define EXTRA_CMSG_SPACE 1024
-
 int socket_open(int family) {
         int fd;
 
@@ -244,7 +240,7 @@ int socket_write_message(sd_netlink *nl, sd_netlink_message *m) {
 
 static int socket_recv_message(int fd, struct iovec *iov, uint32_t *ret_mcast_group, bool peek) {
         union sockaddr_union sender;
-        CMSG_BUFFER_TYPE(CMSG_SPACE(sizeof(struct nl_pktinfo)) + EXTRA_CMSG_SPACE) control;
+        CMSG_BUFFER_TYPE(CMSG_SPACE(sizeof(struct nl_pktinfo))) control;
         struct msghdr msg = {
                 .msg_iov = iov,
                 .msg_iovlen = 1,

src/libsystemd/sd-path/sd-path.c

@@ -320,73 +320,73 @@ static int get_path(uint64_t type, char **buffer, const char **ret) {
         case SD_PATH_USER_DESKTOP:
                 return from_user_dir("XDG_DESKTOP_DIR", buffer, ret);
 
-        case SD_PATH_SYSTEMD_UTIL_DIR:
-                *ret = ROOTPREFIX "lib/systemd";
+        case SD_PATH_SYSTEMD_UTIL:
+                *ret = ROOTPREFIX "/lib/systemd";
                 return 0;
 
-        case SD_PATH_SYSTEMD_SYSTEM_UNIT_DIR:
+        case SD_PATH_SYSTEMD_SYSTEM_UNIT:
                 *ret = SYSTEM_DATA_UNIT_PATH;
                 return 0;
 
-        case SD_PATH_SYSTEMD_SYSTEM_PRESET_DIR:
-                *ret = ROOTPREFIX "lib/systemd/system-preset";
+        case SD_PATH_SYSTEMD_SYSTEM_PRESET:
+                *ret = ROOTPREFIX "/lib/systemd/system-preset";
                 return 0;
 
-        case SD_PATH_SYSTEMD_USER_UNIT_DIR:
+        case SD_PATH_SYSTEMD_USER_UNIT:
                 *ret = USER_DATA_UNIT_DIR;
                 return 0;
 
-        case SD_PATH_SYSTEMD_USER_PRESET_DIR:
-                *ret = ROOTPREFIX "lib/systemd/user-preset";
+        case SD_PATH_SYSTEMD_USER_PRESET:
+                *ret = ROOTPREFIX "/lib/systemd/user-preset";
                 return 0;
 
-        case SD_PATH_SYSTEMD_SYSTEM_CONF_DIR:
+        case SD_PATH_SYSTEMD_SYSTEM_CONF:
                 *ret = SYSTEM_CONFIG_UNIT_DIR;
                 return 0;
 
-        case SD_PATH_SYSTEMD_USER_CONF_DIR:
+        case SD_PATH_SYSTEMD_USER_CONF:
                 *ret = USER_CONFIG_UNIT_DIR;
                 return 0;
 
-        case SD_PATH_SYSTEMD_SYSTEM_GENERATOR_DIR:
+        case SD_PATH_SYSTEMD_SYSTEM_GENERATOR:
                 *ret = SYSTEM_GENERATOR_DIR;
                 return 0;
 
-        case SD_PATH_SYSTEMD_USER_GENERATOR_DIR:
+        case SD_PATH_SYSTEMD_USER_GENERATOR:
                 *ret = USER_GENERATOR_DIR;
                 return 0;
 
-        case SD_PATH_SYSTEMD_SLEEP_DIR:
-                *ret = ROOTPREFIX "lib/systemd/system-sleep";
+        case SD_PATH_SYSTEMD_SLEEP:
+                *ret = ROOTPREFIX "/lib/systemd/system-sleep";
                 return 0;
 
-        case SD_PATH_SYSTEMD_SHUTDOWN_DIR:
-                *ret = ROOTPREFIX "lib/systemd/system-shutdown";
+        case SD_PATH_SYSTEMD_SHUTDOWN:
+                *ret = ROOTPREFIX "/lib/systemd/system-shutdown";
                 return 0;
 
         /* FIXME: systemd.pc uses ${prefix}, but CONF_PATHS_NULSTR doesn't.
          *        Should ${prefix} use in systemd.pc be removed? */
-        case SD_PATH_TMPFILES_DIR:
+        case SD_PATH_TMPFILES:
                 *ret = "/usr/lib/tmpfiles.d";
                 return 0;
 
-        case SD_PATH_SYSUSERS_DIR:
-                *ret = "/usr/lib/sysusers.d";
+        case SD_PATH_SYSUSERS:
+                *ret = ROOTPREFIX "/lib/sysusers.d";
                 return 0;
 
-        case SD_PATH_SYSCTL_DIR:
-                *ret = "/usr/lib/sysctl.d";
+        case SD_PATH_SYSCTL:
+                *ret = ROOTPREFIX "/lib/sysctl.d";
                 return 0;
 
-        case SD_PATH_BINFMT_DIR:
-                *ret = "/usr/lib/binfmt.d";
+        case SD_PATH_BINFMT:
+                *ret = ROOTPREFIX "/lib/binfmt.d";
                 return 0;
 
-        case SD_PATH_MODULES_LOAD_DIR:
-                *ret = "/usr/lib/modules-load.d";
+        case SD_PATH_MODULES_LOAD:
+                *ret = ROOTPREFIX "/lib/modules-load.d";
                 return 0;
 
-        case SD_PATH_CATALOG_DIR:
+        case SD_PATH_CATALOG:
                 *ret = "/usr/lib/systemd/catalog";
                 return 0;
         }
@@ -607,10 +607,10 @@ static int get_search(uint64_t type, char ***list) {
         case SD_PATH_SEARCH_BINARIES_DEFAULT:
                 return strv_from_nulstr(list, DEFAULT_PATH_NULSTR);
 
-        case SD_PATH_SYSTEMD_SYSTEM_UNIT_PATH:
-        case SD_PATH_SYSTEMD_USER_UNIT_PATH: {
+        case SD_PATH_SYSTEMD_SEARCH_SYSTEM_UNIT:
+        case SD_PATH_SYSTEMD_SEARCH_USER_UNIT: {
                 _cleanup_(lookup_paths_free) LookupPaths lp = {};
-                const UnitFileScope scope = type == SD_PATH_SYSTEMD_SYSTEM_UNIT_PATH ?
+                const UnitFileScope scope = type == SD_PATH_SYSTEMD_SEARCH_SYSTEM_UNIT ?
                                                     UNIT_FILE_SYSTEM : UNIT_FILE_USER;
 
                 r = lookup_paths_init(&lp, scope, 0, NULL);
@@ -621,10 +621,10 @@ static int get_search(uint64_t type, char ***list) {
                 return 0;
         }
 
-        case SD_PATH_SYSTEMD_SYSTEM_GENERATOR_PATH:
-        case SD_PATH_SYSTEMD_USER_GENERATOR_PATH: {
+        case SD_PATH_SYSTEMD_SEARCH_SYSTEM_GENERATOR:
+        case SD_PATH_SYSTEMD_SEARCH_USER_GENERATOR: {
                 char **t;
-                const UnitFileScope scope = type == SD_PATH_SYSTEMD_SYSTEM_GENERATOR_PATH ?
+                const UnitFileScope scope = type == SD_PATH_SYSTEMD_SEARCH_SYSTEM_GENERATOR ?
                                                     UNIT_FILE_SYSTEM : UNIT_FILE_USER;
 
                 t = generator_binary_paths(scope);
@@ -635,7 +635,7 @@ static int get_search(uint64_t type, char ***list) {
                 return 0;
         }
 
-        case SD_PATH_SYSTEMD_NETWORK_PATH:
+        case SD_PATH_SYSTEMD_SEARCH_NETWORK:
                 return strv_from_nulstr(list, NETWORK_DIRS_NULSTR);
 
         }

src/network/networkd-dhcp6.c

@@ -26,6 +26,10 @@ static Link *dhcp6_prefix_get(Manager *m, struct in6_addr *addr);
 static int dhcp6_prefix_add(Manager *m, struct in6_addr *addr, Link *link);
 static int dhcp6_prefix_remove_all(Manager *m, Link *link);
 static bool dhcp6_link_has_dhcpv6_prefix(Link *link);
+static int dhcp6_assign_delegated_prefix(Link *link, const struct in6_addr *prefix,
+                                         uint8_t prefix_len,
+                                         uint32_t lifetime_preferred,
+                                         uint32_t lifetime_valid);
 
 static bool dhcp6_get_prefix_delegation(Link *link) {
         if (!link->network)
@@ -191,6 +195,12 @@ static int dhcp6_pd_prefix_assign(Link *link, struct in6_addr *prefix,
         if (r < 0)
                 return r;
 
+        if (link->network->dhcp6_pd_assign_prefix) {
+                r = dhcp6_assign_delegated_prefix(link, prefix, prefix_len, lifetime_preferred, lifetime_valid);
+                if (r < 0)
+                        return r;
+        }
+
         return sd_radv_start(radv);
 }
 
@@ -1018,3 +1028,43 @@ static bool dhcp6_link_has_dhcpv6_prefix(Link *link) {
 
         return false;
 }
+
+static int dhcp6_assign_delegated_prefix(Link *link,
+                                         const struct in6_addr *prefix,
+                                         uint8_t prefix_len,
+                                         uint32_t lifetime_preferred,
+                                         uint32_t lifetime_valid) {
+        _cleanup_(address_freep) Address *address = NULL;
+        int r;
+
+        assert(link);
+        assert(link->network);
+        assert(prefix);
+
+        if (!link->network->dhcp6_pd_assign_prefix)
+                return 0;
+
+        r = address_new(&address);
+        if (r < 0)
+                return log_link_error_errno(link, r, "Could not allocate address: %m");
+
+        address->in_addr.in6 = *prefix;
+        r = generate_ipv6_eui_64_address(link, &address->in_addr.in6);
+        if (r < 0)
+                return log_link_warning_errno(link, r, "Failed to generate EUI64 address for DHCPv6 acquired delegated prefix: %m");
+
+        address->prefixlen = prefix_len;
+        address->family = AF_INET6;
+        address->cinfo.ifa_prefered = lifetime_preferred;
+        address->cinfo.ifa_valid = lifetime_valid;
+
+        link_set_state(link, LINK_STATE_CONFIGURING);
+
+        r = address_configure(address, link, address_handler, true);
+        if (r < 0)
+                return log_link_warning_errno(link, r, "Could not set addresses: %m");
+        if (r > 0)
+                link->address_messages++;
+
+        return 0;
+}

src/network/networkd-link.c

@@ -1173,7 +1173,7 @@ static int link_request_set_neighbors(Link *link) {
         return 0;
 }
 
-static int address_handler(sd_netlink *rtnl, sd_netlink_message *m, Link *link) {
+int address_handler(sd_netlink *rtnl, sd_netlink_message *m, Link *link) {
         int r;
 
         assert(rtnl);

src/network/networkd-link.h

@@ -228,6 +228,7 @@ int link_request_set_routes(Link *link);
 int link_request_set_nexthop(Link *link);
 
 int link_reconfigure(Link *link, bool force);
+int address_handler(sd_netlink *rtnl, sd_netlink_message *m, Link *link);
 
 CONFIG_PARSER_PROTOTYPE(config_parse_link_ipv6_address_gen_mode);
 

src/network/networkd-network-gperf.gperf

@@ -102,7 +102,7 @@ Network.ProxyARP,                            config_parse_tristate,
 Network.IPv6ProxyNDPAddress,                 config_parse_ipv6_proxy_ndp_address,                      0,                             0
 Network.BindCarrier,                         config_parse_strv,                                        0,                             offsetof(Network, bind_carrier)
 Network.ConfigureWithoutCarrier,             config_parse_bool,                                        0,                             offsetof(Network, configure_without_carrier)
-Network.IgnoreCarrierLoss,                   config_parse_bool,                                        0,                             offsetof(Network, ignore_carrier_loss)
+Network.IgnoreCarrierLoss,                   config_parse_tristate,                                    0,                             offsetof(Network, ignore_carrier_loss)
 Network.KeepConfiguration,                   config_parse_keep_configuration,                          0,                             offsetof(Network, keep_configuration)
 Address.Address,                             config_parse_address,                                     0,                             0
 Address.Peer,                                config_parse_address,                                     0,                             0
@@ -199,6 +199,7 @@ DHCPv6.RequestOptions,                       config_parse_dhcp_request_options,
 DHCPv6.UserClass,                            config_parse_dhcp_user_class,                             AF_INET6,                      offsetof(Network, dhcp6_user_class)
 DHCPv6.VendorClass,                          config_parse_dhcp_vendor_class,                           0,                             offsetof(Network, dhcp6_vendor_class)
 DHCPv6.ForceDHCPv6PDOtherInformation,        config_parse_bool,                                        0,                             offsetof(Network, dhcp6_force_pd_other_information)
+DHCPv6.AssignAcquiredDelegatedPrefixAddress, config_parse_bool,                                        0,                             offsetof(Network, dhcp6_pd_assign_prefix)
 DHCPv6.PrefixDelegationHint,                 config_parse_dhcp6_pd_hint,                               0,                             0
 DHCPv6.WithoutRA,                            config_parse_bool,                                        0,                             offsetof(Network, dhcp6_without_ra)
 DHCPv6.SendOption,                           config_parse_dhcp_send_option,                            AF_INET6,                      offsetof(Network, dhcp6_client_send_options)

src/network/networkd-network.c

@@ -271,6 +271,9 @@ int network_verify(Network *network) {
         if (network->dhcp_use_gateway < 0)
                 network->dhcp_use_gateway = network->dhcp_use_routes;
 
+        if (network->ignore_carrier_loss < 0)
+                network->ignore_carrier_loss = network->configure_without_carrier;
+
         if (network->dhcp_critical >= 0) {
                 if (network->keep_configuration >= 0)
                         log_warning("%s: Both KeepConfiguration= and deprecated CriticalConnection= are set. "
@@ -409,6 +412,8 @@ int network_load_one(Manager *manager, OrderedHashmap **networks, const char *fi
                 .dhcp6_use_ntp = true,
                 .dhcp6_use_dns = true,
 
+                .dhcp6_pd_assign_prefix = true,
+
                 .dhcp_server_emit_dns = true,
                 .dhcp_server_emit_ntp = true,
                 .dhcp_server_emit_sip = true,
@@ -461,6 +466,8 @@ int network_load_one(Manager *manager, OrderedHashmap **networks, const char *fi
                 .ipv6_accept_ra_route_table_set = false,
                 .ipv6_accept_ra_start_dhcp6_client = true,
 
+                .configure_without_carrier = false,
+                .ignore_carrier_loss = -1,
                 .keep_configuration = _KEEP_CONFIGURATION_INVALID,
                 .ipv6_address_gen_mode = _LINK_IPV6_ADDRESS_GEN_MODE_INVALID,
                 .can_triple_sampling = -1,

src/network/networkd-network.h

@@ -192,6 +192,7 @@ struct Network {
         bool dhcp6_force_pd_other_information; /* Start DHCPv6 PD also when 'O'
                                                   RA flag is set, see RFC 7084,
                                                   WPD-4 */
+        bool dhcp6_pd_assign_prefix;
 
         /* Bridge Support */
         int use_bpdu;
@@ -258,7 +259,7 @@ struct Network {
         int allmulticast;
         bool unmanaged;
         bool configure_without_carrier;
-        bool ignore_carrier_loss;
+        int ignore_carrier_loss;
         KeepConfiguration keep_configuration;
         LinkIPv6AddressGenMode ipv6_address_gen_mode;
         uint32_t iaid;

src/path/path.c

@@ -59,30 +59,30 @@ static const char* const path_table[_SD_PATH_MAX] = {
         [SD_PATH_SEARCH_STATE_FACTORY]            = "search-state-factory",
         [SD_PATH_SEARCH_CONFIGURATION]            = "search-configuration",
 
-        [SD_PATH_SYSTEMD_UTIL_DIR]              = "systemd-util-dir",
-        [SD_PATH_SYSTEMD_SYSTEM_UNIT_DIR]       = "systemd-system-unit-dir",
-        [SD_PATH_SYSTEMD_SYSTEM_PRESET_DIR]     = "systemd-system-preset-dir",
-        [SD_PATH_SYSTEMD_USER_UNIT_DIR]         = "systemd-user-unit-dir",
-        [SD_PATH_SYSTEMD_USER_PRESET_DIR]       = "systemd-user-preset-dir",
-        [SD_PATH_SYSTEMD_SYSTEM_CONF_DIR]       = "systemd-system-conf-dir",
-        [SD_PATH_SYSTEMD_USER_CONF_DIR]         = "systemd-user-conf-dir",
-        [SD_PATH_SYSTEMD_SYSTEM_UNIT_PATH]      = "systemd-system-unit-path",
-        [SD_PATH_SYSTEMD_USER_UNIT_PATH]        = "systemd-user-unit-path",
-        [SD_PATH_SYSTEMD_SYSTEM_GENERATOR_DIR]  = "systemd-system-generator-dir",
-        [SD_PATH_SYSTEMD_USER_GENERATOR_DIR]    = "systemd-user-generator-dir",
-        [SD_PATH_SYSTEMD_SYSTEM_GENERATOR_PATH] = "systemd-system-generator-path",
-        [SD_PATH_SYSTEMD_USER_GENERATOR_PATH]   = "systemd-user-generator-path",
-        [SD_PATH_SYSTEMD_SLEEP_DIR]             = "systemd-sleep-dir",
-        [SD_PATH_SYSTEMD_SHUTDOWN_DIR]          = "systemd-shutdown-dir",
+        [SD_PATH_SYSTEMD_UTIL]                    = "systemd-util",
+        [SD_PATH_SYSTEMD_SYSTEM_UNIT]             = "systemd-system-unit",
+        [SD_PATH_SYSTEMD_SYSTEM_PRESET]           = "systemd-system-preset",
+        [SD_PATH_SYSTEMD_SYSTEM_CONF]             = "systemd-system-conf",
+        [SD_PATH_SYSTEMD_SEARCH_SYSTEM_UNIT]      = "systemd-system-unit",
+        [SD_PATH_SYSTEMD_SYSTEM_GENERATOR]        = "systemd-system-generator",
+        [SD_PATH_SYSTEMD_SEARCH_SYSTEM_GENERATOR] = "systemd-system-generator",
+        [SD_PATH_SYSTEMD_USER_UNIT]               = "systemd-user-unit",
+        [SD_PATH_SYSTEMD_USER_PRESET]             = "systemd-user-preset",
+        [SD_PATH_SYSTEMD_USER_CONF]               = "systemd-user-conf",
+        [SD_PATH_SYSTEMD_SEARCH_USER_UNIT]        = "systemd-user-unit",
+        [SD_PATH_SYSTEMD_SEARCH_USER_GENERATOR]   = "systemd-user-generator",
+        [SD_PATH_SYSTEMD_USER_GENERATOR]          = "systemd-user-generator",
+        [SD_PATH_SYSTEMD_SLEEP]                   = "systemd-sleep",
+        [SD_PATH_SYSTEMD_SHUTDOWN]                = "systemd-shutdown",
 
-        [SD_PATH_TMPFILES_DIR]                  = "tmpfiles-dir",
-        [SD_PATH_SYSUSERS_DIR]                  = "sysusers-dir",
-        [SD_PATH_SYSCTL_DIR]                    = "sysctl-dir",
-        [SD_PATH_BINFMT_DIR]                    = "binfmt-dir",
-        [SD_PATH_MODULES_LOAD_DIR]              = "modules-load-dir",
-        [SD_PATH_CATALOG_DIR]                   = "catalog-dir",
+        [SD_PATH_TMPFILES]                        = "tmpfiles",
+        [SD_PATH_SYSUSERS]                        = "sysusers",
+        [SD_PATH_SYSCTL]                          = "sysctl",
+        [SD_PATH_BINFMT]                          = "binfmt",
+        [SD_PATH_MODULES_LOAD]                    = "modules-load",
+        [SD_PATH_CATALOG]                         = "catalog",
 
-        [SD_PATH_SYSTEMD_NETWORK_PATH]          = "systemd-network-path",
+        [SD_PATH_SYSTEMD_SEARCH_NETWORK]          = "systemd-search-network",
 };
 
 static int list_homes(void) {

src/resolve/resolved-dns-stream.c

@@ -88,6 +88,7 @@ static int dns_stream_complete(DnsStream *s, int error) {
 
 static int dns_stream_identify(DnsStream *s) {
         CMSG_BUFFER_TYPE(CMSG_SPACE(MAXSIZE(struct in_pktinfo, struct in6_pktinfo))
+                         + CMSG_SPACE(int) + /* for the TTL */
                          + EXTRA_CMSG_SPACE /* kernel appears to require extra space */) control;
         struct msghdr mh = {};
         struct cmsghdr *cmsg;

src/shared/bus-unit-util.c

@@ -1632,6 +1632,7 @@ static int bus_append_socket_property(sd_bus_message *m, const char *field, cons
                               "Broadcast",
                               "PassCredentials",
                               "PassSecurity",
+                              "PassPacketInfo",
                               "ReusePort",
                               "RemoveOnStop",
                               "SELinuxContextFromNet"))

src/systemd/sd-messages.h

@@ -161,6 +161,11 @@ _SD_BEGIN_DECLARATIONS;
 #define SD_MESSAGE_UNSAFE_USER_NAME       SD_ID128_MAKE(b6,1f,da,c6,12,e9,4b,91,82,28,5b,99,88,43,06,1f)
 #define SD_MESSAGE_UNSAFE_USER_NAME_STR   SD_ID128_MAKE_STR(b6,1f,da,c6,12,e9,4b,91,82,28,5b,99,88,43,06,1f)
 
+#define SD_MESSAGE_MOUNT_POINT_PATH_NOT_SUITABLE \
+                                          SD_ID128_MAKE(1b,3b,b9,40,37,f0,4b,bf,81,02,8e,13,5a,12,d2,93)
+#define SD_MESSAGE_MOUNT_POINT_PATH_NOT_SUITABLE_STR \
+                                          SD_ID128_MAKE_STR(1b,3b,b9,40,37,f0,4b,bf,81,02,8e,13,5a,12,d2,93)
+
 _SD_END_DECLARATIONS;
 
 #endif

src/systemd/sd-path.h

@@ -78,32 +78,37 @@ enum {
         SD_PATH_SEARCH_STATE_FACTORY,
         SD_PATH_SEARCH_CONFIGURATION,
 
-        /* Various systemd paths, generally mirroring systemd.pc */
-        SD_PATH_SYSTEMD_UTIL_DIR,
-        SD_PATH_SYSTEMD_SYSTEM_UNIT_DIR,
-        SD_PATH_SYSTEMD_SYSTEM_PRESET_DIR,
-        SD_PATH_SYSTEMD_USER_UNIT_DIR,
-        SD_PATH_SYSTEMD_USER_PRESET_DIR,
-        SD_PATH_SYSTEMD_SYSTEM_CONF_DIR,
-        SD_PATH_SYSTEMD_USER_CONF_DIR,
-        SD_PATH_SYSTEMD_SYSTEM_UNIT_PATH,
-        SD_PATH_SYSTEMD_USER_UNIT_PATH,
-        SD_PATH_SYSTEMD_SYSTEM_GENERATOR_DIR,
-        SD_PATH_SYSTEMD_USER_GENERATOR_DIR,
-        SD_PATH_SYSTEMD_SYSTEM_GENERATOR_PATH,
-        SD_PATH_SYSTEMD_USER_GENERATOR_PATH,
-        SD_PATH_SYSTEMD_SLEEP_DIR,
-        SD_PATH_SYSTEMD_SHUTDOWN_DIR,
+        /* Various systemd paths, generally mirroring systemd.pc — Except we drop the "dir" suffix (and
+         * replaces "path" by "search"), since this API is about dirs/paths anyway, and contains "path"
+         * already in the prefix */
+        SD_PATH_SYSTEMD_UTIL,
+        SD_PATH_SYSTEMD_SYSTEM_UNIT,
+        SD_PATH_SYSTEMD_SYSTEM_PRESET,
+        SD_PATH_SYSTEMD_SYSTEM_CONF,
+        SD_PATH_SYSTEMD_USER_UNIT,
+        SD_PATH_SYSTEMD_USER_PRESET,
+        SD_PATH_SYSTEMD_USER_CONF,
 
-        SD_PATH_TMPFILES_DIR,
-        SD_PATH_SYSUSERS_DIR,
-        SD_PATH_SYSCTL_DIR,
-        SD_PATH_BINFMT_DIR,
-        SD_PATH_MODULES_LOAD_DIR,
-        SD_PATH_CATALOG_DIR,
+        SD_PATH_SYSTEMD_SEARCH_SYSTEM_UNIT,
+        SD_PATH_SYSTEMD_SEARCH_USER_UNIT,
+
+        SD_PATH_SYSTEMD_SYSTEM_GENERATOR,
+        SD_PATH_SYSTEMD_USER_GENERATOR,
+        SD_PATH_SYSTEMD_SEARCH_SYSTEM_GENERATOR,
+        SD_PATH_SYSTEMD_SEARCH_USER_GENERATOR,
+
+        SD_PATH_SYSTEMD_SLEEP,
+        SD_PATH_SYSTEMD_SHUTDOWN,
+
+        SD_PATH_TMPFILES,
+        SD_PATH_SYSUSERS,
+        SD_PATH_SYSCTL,
+        SD_PATH_BINFMT,
+        SD_PATH_MODULES_LOAD,
+        SD_PATH_CATALOG,
 
         /* systemd-networkd search paths */
-        SD_PATH_SYSTEMD_NETWORK_PATH,
+        SD_PATH_SYSTEMD_SEARCH_NETWORK,
 
         _SD_PATH_MAX,
 };

src/udev/net/link-config.c

@@ -332,7 +332,9 @@ static int get_mac(sd_device *device, MACAddressPolicy policy, struct ether_addr
                 /* We require genuine randomness here, since we want to make sure we won't collide with other
                  * systems booting up at the very same time. We do allow RDRAND however, since this is not
                  * cryptographic key material. */
-                genuine_random_bytes(mac->ether_addr_octet, ETH_ALEN, RANDOM_ALLOW_RDRAND);
+                r = genuine_random_bytes(mac->ether_addr_octet, ETH_ALEN, RANDOM_ALLOW_RDRAND);
+                if (r < 0)
+                        return log_device_error_errno(device, r, "Failed to acquire random data to generate MAC: %m");
         } else {
                 uint64_t result;
 

src/udev/udevd.c

@@ -443,6 +443,10 @@ static int worker_device_monitor_handler(sd_device_monitor *monitor, sd_device *
         assert(manager);
 
         r = worker_process_device(manager, dev);
+        if (r == -EAGAIN)
+                /* if we couldn't acquire the flock(), then proceed quietly */
+                log_device_debug_errno(dev, r, "Device currently locked, not processing.");
+        else {
                 if (r < 0)
                         log_device_warning_errno(dev, r, "Failed to process device, ignoring: %m");
 
@@ -450,6 +454,7 @@ static int worker_device_monitor_handler(sd_device_monitor *monitor, sd_device *
                 r = device_monitor_send_device(monitor, NULL, dev);
                 if (r < 0)
                         log_device_warning_errno(dev, r, "Failed to send device, ignoring: %m");
+        }
 
         /* send udevd the result of the event execution */
         r = worker_send_message(manager->worker_watch[WRITE_END]);

src/xdg-autostart-generator/xdg-autostart-service.c

@@ -73,7 +73,6 @@ static int xdg_config_parse_bool(
                 void *userdata) {
 
         bool *b = data;
-        const char *value;
 
         assert(filename);
         assert(lvalue);
@@ -85,7 +84,7 @@ static int xdg_config_parse_bool(
         else if (streq(rvalue, "false"))
                 *b = false;
         else
-                return log_syntax(unit, LOG_ERR, filename, line, SYNTHETIC_ERRNO(EINVAL), "Invalid value for boolean: %s", value);
+                return log_syntax(unit, LOG_ERR, filename, line, SYNTHETIC_ERRNO(EINVAL), "Invalid value for boolean: %s", rvalue);
 
         return 0;
 }

test/fuzz/fuzz-network-parser/directives.network

@@ -119,6 +119,7 @@ SendOption=
 RequestOptions=
 UserClass=
 VendorClass=
+AssignAcquiredDelegatedPrefixAddress=
 [Route]
 Destination=
 Protocol=

test/fuzz/fuzz-unit-file/directives.service

@@ -164,6 +164,7 @@ PIDFile=
 PartOf=
 PassCredentials=
 PassSecurity=
+PassPacketInfo=
 PathChanged=
 PathExists=
 PathExistsGlob=

test/test-network/conf/25-test1.network

@@ -4,4 +4,3 @@ Name=test1
 [Network]
 Address=192.168.0.15/24
 Gateway=192.168.0.1
-ConfigureWithoutCarrier=true

test/test-network/conf/25-test1.network.d/configure-without-carrier.conf

@@ -0,0 +1,2 @@
+[Network]
+ConfigureWithoutCarrier=true

test/test-network/conf/25-test1.network.d/ignore-carrier-loss-no.conf

@@ -0,0 +1,2 @@
+[Network]
+IgnoreCarrierLoss=false

test/test-network/conf/26-bridge-configure-without-carrier.network

@@ -0,0 +1,9 @@
+[Match]
+Name=bridge99
+
+[Network]
+LinkLocalAddressing=yes
+IPv6AcceptRA=no
+ConfigureWithoutCarrier=yes
+Address=10.1.2.3/24
+Gateway=10.1.2.1

test/test-network/systemd-networkd-tests.py

@@ -445,6 +445,9 @@ class Utilities():
     def check_link_exists(self, link):
         self.assertTrue(link_exists(link))
 
+    def check_link_attr(self, *args):
+        self.assertEqual(read_link_attr(*args[:-1]), args[-1]);
+
     def wait_operstate(self, link, operstate='degraded', setup_state='configured', setup_timeout=5, fail_assert=True):
         """Wait for the link to reach the specified operstate and/or setup state.
 
@@ -1671,11 +1674,11 @@ class NetworkdNetworkTests(unittest.TestCase, Utilities):
         '25-gateway-next-static.network',
         '25-sysctl-disable-ipv6.network',
         '25-sysctl.network',
+        '25-test1.network',
         '25-veth-peer.network',
         '25-veth.netdev',
         '25-vrf.netdev',
         '26-link-local-addressing-ipv6.network',
-        'configure-without-carrier.network',
         'routing-policy-rule-dummy98.network',
         'routing-policy-rule-test1.network']
 
@@ -1762,15 +1765,56 @@ class NetworkdNetworkTests(unittest.TestCase, Utilities):
         self.assertNotRegex(output, '192.168.100.10/24')
 
     def test_configure_without_carrier(self):
-        copy_unit_to_networkd_unit_path('configure-without-carrier.network', '11-dummy.netdev')
+        copy_unit_to_networkd_unit_path('11-dummy.netdev')
         start_networkd()
-        self.wait_online(['test1:routable'])
+        self.wait_operstate('test1', 'off', '')
+        check_output('ip link set dev test1 up carrier off')
+
+        copy_unit_to_networkd_unit_path('25-test1.network.d/configure-without-carrier.conf', dropins=False)
+        restart_networkd()
+        self.wait_online(['test1:no-carrier'])
+
+        carrier_map = {'on': '1', 'off': '0'}
+        routable_map = {'on': 'routable', 'off': 'no-carrier'}
+        for carrier in ['off', 'on', 'off']:
+            with self.subTest(carrier=carrier):
+                if carrier_map[carrier] != read_link_attr('test1', 'carrier'):
+                    check_output(f'ip link set dev test1 carrier {carrier}')
+                self.wait_online([f'test1:{routable_map[carrier]}'])
 
                 output = check_output(*networkctl_cmd, '-n', '0', 'status', 'test1', env=env)
                 print(output)
                 self.assertRegex(output, '192.168.0.15')
                 self.assertRegex(output, '192.168.0.1')
-        self.assertRegex(output, 'routable')
+                self.assertRegex(output, routable_map[carrier])
+
+    def test_configure_without_carrier_yes_ignore_carrier_loss_no(self):
+        copy_unit_to_networkd_unit_path('11-dummy.netdev')
+        start_networkd()
+        self.wait_operstate('test1', 'off', '')
+        check_output('ip link set dev test1 up carrier off')
+
+        copy_unit_to_networkd_unit_path('25-test1.network')
+        restart_networkd()
+        self.wait_online(['test1:no-carrier'])
+
+        carrier_map = {'on': '1', 'off': '0'}
+        routable_map = {'on': 'routable', 'off': 'no-carrier'}
+        for (carrier, have_config) in [('off', True), ('on', True), ('off', False)]:
+            with self.subTest(carrier=carrier, have_config=have_config):
+                if carrier_map[carrier] != read_link_attr('test1', 'carrier'):
+                    check_output(f'ip link set dev test1 carrier {carrier}')
+                self.wait_online([f'test1:{routable_map[carrier]}'])
+
+                output = check_output(*networkctl_cmd, '-n', '0', 'status', 'test1', env=env)
+                print(output)
+                if have_config:
+                    self.assertRegex(output, '192.168.0.15')
+                    self.assertRegex(output, '192.168.0.1')
+                else:
+                    self.assertNotRegex(output, '192.168.0.15')
+                    self.assertNotRegex(output, '192.168.0.1')
+                self.assertRegex(output, routable_map[carrier])
 
     def test_routing_policy_rule(self):
         copy_unit_to_networkd_unit_path('routing-policy-rule-test1.network', '11-dummy.netdev')
@@ -2608,6 +2652,7 @@ class NetworkdBridgeTests(unittest.TestCase, Utilities):
         '11-dummy.netdev',
         '12-dummy.netdev',
         '26-bridge.netdev',
+        '26-bridge-configure-without-carrier.network',
         '26-bridge-slave-interface-1.network',
         '26-bridge-slave-interface-2.network',
         '26-bridge-vlan-master.network',
@@ -2722,6 +2767,55 @@ class NetworkdBridgeTests(unittest.TestCase, Utilities):
         print(output)
         self.assertRegex(output, 'ff00::/8 table local metric 256 (linkdown )?pref medium')
 
+    def test_bridge_configure_without_carrier(self):
+        copy_unit_to_networkd_unit_path('26-bridge.netdev', '26-bridge-configure-without-carrier.network',
+                                        '11-dummy.netdev')
+        start_networkd()
+
+        # With ConfigureWithoutCarrier=yes, the bridge should remain configured for all these situations
+        for test in ['no-slave', 'add-slave', 'slave-up', 'slave-no-carrier', 'slave-carrier', 'slave-down']:
+            with self.subTest(test=test):
+                if test == 'no-slave':
+                    # bridge has no slaves; it's up but *might* not have carrier
+                    self.wait_online(['bridge99:no-carrier'])
+                    # due to a bug in the kernel, newly-created bridges are brought up
+                    # *with* carrier, unless they have had any setting changed; e.g.
+                    # their mac set, priority set, etc.  Then, they will lose carrier
+                    # as soon as a (down) slave interface is added, and regain carrier
+                    # again once the slave interface is brought up.
+                    #self.check_link_attr('bridge99', 'carrier', '0')
+                elif test == 'add-slave':
+                    # add slave to bridge, but leave it down; bridge is definitely no-carrier
+                    self.check_link_attr('test1', 'operstate', 'down')
+                    check_output('ip link set dev test1 master bridge99')
+                    self.wait_online(['bridge99:no-carrier:no-carrier'])
+                    self.check_link_attr('bridge99', 'carrier', '0')
+                elif test == 'slave-up':
+                    # bring up slave, which will have carrier; bridge gains carrier
+                    check_output('ip link set dev test1 up')
+                    self.wait_online(['bridge99:routable'])
+                    self.check_link_attr('bridge99', 'carrier', '1')
+                elif test == 'slave-no-carrier':
+                    # drop slave carrier; bridge loses carrier
+                    check_output('ip link set dev test1 carrier off')
+                    self.wait_online(['bridge99:no-carrier:no-carrier'])
+                    self.check_link_attr('bridge99', 'carrier', '0')
+                elif test == 'slave-carrier':
+                    # restore slave carrier; bridge gains carrier
+                    check_output('ip link set dev test1 carrier on')
+                    self.wait_online(['bridge99:routable'])
+                    self.check_link_attr('bridge99', 'carrier', '1')
+                elif test == 'slave-down':
+                    # bring down slave; bridge loses carrier
+                    check_output('ip link set dev test1 down')
+                    self.wait_online(['bridge99:no-carrier:no-carrier'])
+                    self.check_link_attr('bridge99', 'carrier', '0')
+
+                output = check_output(*networkctl_cmd, '-n', '0', 'status', 'bridge99', env=env)
+                print(output)
+                self.assertRegex(output, '10.1.2.3')
+                self.assertRegex(output, '10.1.2.1')
+
     def test_bridge_ignore_carrier_loss(self):
         copy_unit_to_networkd_unit_path('11-dummy.netdev', '12-dummy.netdev', '26-bridge.netdev',
                                         '26-bridge-slave-interface-1.network', '26-bridge-slave-interface-2.network',

units/systemd-homed.service.in

@@ -37,3 +37,4 @@ SystemCallFilter=@system-service @mount
 [Install]
 WantedBy=multi-user.target
 Alias=dbus-org.freedesktop.home1.service
+Also=systemd-userdbd.service

units/systemd-networkd.socket

@@ -17,7 +17,7 @@ Before=sockets.target
 [Socket]
 ReceiveBuffer=128M
 ListenNetlink=route 1361
-PassCredentials=yes
+PassPacketInfo=yes
 
 [Install]
 WantedBy=sockets.target