[Bug 2009743] Re: networkd: classless routes served by DHCP are created incorrectly
Launchpad Bug Tracker
2009743 at bugs.launchpad.net
Tue Sep 12 23:33:37 UTC 2023
This bug was fixed in the package systemd - 249.11-0ubuntu3.10
---------------
systemd (249.11-0ubuntu3.10) jammy; urgency=medium
[ Nick Rosbrook ]
* debian/tests/tests-in-lxd: use --reuse flag in lxc publish (LP: #2023229)
File: debian/tests/tests-in-lxd
https://git.launchpad.net/~ubuntu-core-dev/ubuntu/+source/systemd/commit/?id=85b2ceddff1a6cc1ddbca8a1b7e5381d146e6313
* pstore: only try to load efi_pstore module (LP: #2023462)
File: debian/patches/lp1978079-efi-pstore-not-cleared-on-boot.patch
https://git.launchpad.net/~ubuntu-core-dev/ubuntu/+source/systemd/commit/?id=7600bbfb1e8a399e5aeb1010a20deda3e5a06c89
* shutdown: get only active md arrays. (LP: #2025563)
File: debian/patches/lp2025563-shutdown-get-only-active-md-arrays.patch
https://git.launchpad.net/~ubuntu-core-dev/ubuntu/+source/systemd/commit/?id=416a9245c8f0efbedcc4395cada23cb09c685ec3
* udev-rules: fix nvme symlink creation on namespace changes (LP: #2028180)
File: debian/patches/lp2028180-udev-rules-fix-nvme-symlink-creation-on-namespace-changes.patch
https://git.launchpad.net/~ubuntu-core-dev/ubuntu/+source/systemd/commit/?id=26e85b944da9098e66fc0c39f64ee40254c0c278
* core: reorder systemd arguments on reexec (LP: #2013543)
File: debian/patches/lp2013543-core-reorder-systemd-arguments-on-reexec.patch
https://git.launchpad.net/~ubuntu-core-dev/ubuntu/+source/systemd/commit/?id=19ba0f20d311642596dc65fa5d6eb96a2d4be280
* network/dhcp4: do not ignore the gateway even if the destination is in same network (LP: #2009743)
Files:
- debian/patches/lp2009743/network-dhcp4-do-not-ignore-the-gateway-even-if-the-desti.patch
- debian/patches/lp2009743/test-network-add-one-more-testcase-for-DHCPv4-classless-r.patch
https://git.launchpad.net/~ubuntu-core-dev/ubuntu/+source/systemd/commit/?id=73e774a2fb99c82df6d0edd770bb84ab735ec2f0
* Drop debian/UBUNTU-wait-online-exit-if-no-links-are-managed.patch (LP: #1982218)
File: debian/patches/debian/UBUNTU-wait-online-exit-if-no-links-are-managed.patch
https://git.launchpad.net/~ubuntu-core-dev/ubuntu/+source/systemd/commit/?id=cf82f08feea456e1c65895b34bffa8c33d421588
* debian/systemd.postint: do not daemon re-exec if we could hit LP: #2013543
File: debian/systemd.postinst
https://git.launchpad.net/~ubuntu-core-dev/ubuntu/+source/systemd/commit/?id=be484dab06d590b1792a8f016f4292373d0174b7
* binfmt: fix systemd-binfmt in LXD containers (LP: #1999275)
Files:
- debian/patches/lp1999275/binfmt-check-if-binfmt-is-mounted-before-applying-rules.patch
- debian/patches/lp1999275/binfmt-util-also-check-if-binfmt-is-mounted-in-read-write.patch
- debian/patches/lp1999275/binfmt-util-split-out-binfmt_mounted.patch
- debian/patches/lp1999275/unit-check-more-specific-path-to-be-written-by-systemd-bi.patch
https://git.launchpad.net/~ubuntu-core-dev/ubuntu/+source/systemd/commit/?id=0b9eadf05ee6db0e009dacbc71521480095880b3
[ Dan Streetman ]
* Fix machinectl pull-tar and import-tar (LP: #1977630)
Author: Dan Streetman
File: debian/patches/lp1977630-fix_machinectl_pull_tar.patch
https://git.launchpad.net/~ubuntu-core-dev/ubuntu/+source/systemd/commit/?id=1e7d3febe1600c6eb03bd71a17be6a6af52988c7
* make machinectl read-only work (LP: #1991829)
Author: Dan Streetman
File: debian/patches/lp1991829-add-CAP_LINUX_IMMUTABLE-to-systemd-machined-so-it-ca.patch
https://git.launchpad.net/~ubuntu-core-dev/ubuntu/+source/systemd/commit/?id=7a7c47569e0a2d175915eb0b79c60f2611848731
-- Nick Rosbrook <enr0n at ubuntu.com> Mon, 21 Aug 2023 17:11:40 -0400
** Changed in: systemd (Ubuntu Jammy)
Status: Fix Committed => Fix Released
--
You received this bug notification because you are a member of Ubuntu
Foundations Bugs, which is subscribed to systemd in Ubuntu.
https://bugs.launchpad.net/bugs/2009743
Title:
networkd: classless routes served by DHCP are created incorrectly
Status in systemd:
Fix Released
Status in systemd package in Ubuntu:
Fix Released
Status in systemd source package in Jammy:
Fix Released
Status in systemd source package in Lunar:
Fix Released
Bug description:
[Impact]
Classless static routes served by DHCP are ignored by networkd in some
cases. Specifically, the gateway is not being set for routes whenever
the route destination is in the assigned network. This is a regression
in behavior since Focal.
[Test Plan]
This is basically taken from systemd-networkd-tests.py. Using a veth
pair, setup dnsmasq to serve the problematic routes:
$ cat > /etc/systemd/network/25-dhcp-server-veth-peer.network << EOF
[Match]
Name=veth-peer
[Network]
IPv6AcceptRA=no
Address=2600::1/0
Address=192.168.5.1/24
EOF
$ cat > /etc/systemd/network/25-test.network << EOF
[Match]
Name=veth99
[Network]
DHCP=ipv4
IPv6AcceptRA=false
[DHCPv4]
UseRoutes=yes
EOF
$ cat > /etc/systemd/network/25-veth.netdev << EOF
[NetDev]
Name=veth99
Kind=veth
MACAddress=12:34:56:78:9a:bc
[Peer]
Name=veth-peer
MACAddress=12:34:56:78:9a:bd
EOF
$ mkdir -p /etc/systemd/system/systemd-networkd.service.d/
$ cat > /etc/systemd/system/systemd-networkd.service.d/debug.conf << EOF
[Service]
Environment=SYSTEMD_LOG_LEVEL=debug
EOF
$ systemctl daemon-reload
$ systemctl restart systemd-networkd
$ mkdir -p /run/networkd-ci
$ dnsmasq --log-facility=/run/networkd-ci/test-dnsmasq.log --log-queries=extra --log-dhcp --pid-file=/run/networkd-ci/test-dnsmasq.pid --conf-file=/dev/null --bind-interfaces --interface=veth-peer --dhcp-leasefile=/run/networkd-ci/test-dnsmasq.lease --enable-ra --dhcp-range=2600::10,2600::20,2m --dhcp-range=192.168.5.10,192.168.5.200,2m --dhcp-option=option:mtu,1492 --dhcp-option=option:router,192.168.5.1 --port=0 --no-resolv --dhcp-option=option:classless-static-route,0.0.0.0/0,192.168.5.4,8.0.0.0/8,192.168.5.5,192.168.5.64/26,192.168.5.5 &
$ systemctl restart systemd-networkd
On an affected machine, the route to 192.168.5.64 on veth99 will be
missing it's gateway address:
$ ip r show dev veth99 192.168.5.64/26
192.168.5.64/26 proto dhcp scope link src 192.168.5.181 metric 1024
And, there will be a log message explaining that this was done
intentionally:
$ journalctl -u systemd-networkd --grep="veth99.*assigned network"
Aug 03 16:58:49 mantic2 systemd-networkd[1418]: veth99: DHCP: requested route destination 192.168.5.64/26 is in the assigned network 192.168.5.0/24, ignoring gateway address 192.168.5.5
On a fixed machine, the route for to 192.168.5.64 will correctly have
its gateway configured:
$ ip r show dev veth99 192.168.5.64/26
192.168.5.64/26 via 192.168.5.5 proto dhcp src 192.168.5.181 metric 1024
[Where problems could occur]
The patch is in the DHCPv4 client code for handling routes from the
DHCP server. It adds a flag, force_use_gw, to an internal function
that essentially overrides the "ignore" behavior whenever classless
static routes have been given. If we saw regressions, it would be
related to creation of static routes handed down by DHCPv4 servers.
[Original Description]
After upgrading 20.04 systems to 22.04, the classless routes served
via DHCP are not being registered correctly - they are missing the
gateway address.
Expected routes - these are taken from a 20.04 system on the same
network:
$ ip route
default via 10.10.1.1 dev enp24s0 proto dhcp src 10.10.64.12 metric 100
10.0.0.0/8 dev enp24s0 proto kernel scope link src 10.10.64.12
10.88.88.0/24 via 10.10.1.2 dev enp24s0 proto dhcp src 10.10.64.12 metric 100
10.96.0.0/11 via 10.10.1.2 dev enp24s0 proto dhcp src 10.10.64.12 metric 100
Actual routes - these are the routes created in one of the affected
22.04 systems:
$ ip route
default via 10.10.1.1 dev bond0 proto dhcp src 10.10.48.20 metric 100
8.8.8.8 via 10.10.1.1 dev bond0 proto dhcp src 10.10.48.20 metric 100
10.0.0.0/8 dev bond0 proto kernel scope link src 10.10.48.20 metric 100
10.10.1.1 dev bond0 proto dhcp scope link src 10.10.48.20 metric 100
10.10.1.2 dev bond0 proto dhcp scope link src 10.10.48.20 metric 100
10.88.88.0/24 dev bond0 proto dhcp scope link src 10.10.48.20 metric 100
10.96.0.0/11 dev bond0 proto dhcp scope link src 10.10.48.20 metric 100
Note the routes for 10.88.88.0/24 and 10.96.0.0/11 are missing the "via" gateway address, and therefore don't work.
(For some reason there are also static routes created for DNS server (8.8.8.8) and known gateways (10.10.1.1 and 10.10.1.2). These are redundant but harmless.)
Both the working and non-working systems are being managed by netplan.
The non-working system has a bonded interface but I have checked that
is not the cause of the problem - using a physical interface directly
has the same result.
I have attached the files /etc/netplan/00-installer-config.yaml and
/run/systemd/network/10-netplan-bond0.network of the affected system.
Affected system:
Ubuntu version: Ubuntu 22.04.2 LTS
systemd version: 249.11-0ubuntu3.6
Older system not affected:
Ubuntu version: Ubuntu 20.04.5 LTS
systemd version: 245.4-4ubuntu3.19
To manage notifications about this bug go to:
https://bugs.launchpad.net/systemd/+bug/2009743/+subscriptions
More information about the foundations-bugs
mailing list