NetworkManager crashes when updating wpa-eap connections

Checking the journal errors from some reports those warnings are found

nm-device: NM-9ca0c167-eb7c-4200-8766-38707689ef3b: the renderer for nm-devices must be NetworkManager, it will be used instead of the defined one.

or

<error> [1696737400.9276] BUG: the profile cannot be stored in keyfile format without becoming unusable: invalid connection: 802-1x: 'wpa-eap' security requires '802-1x' setting presence

or

<error> [1696771280.2003] BUG: the profile cannot be stored in keyfile format without becoming unusable: cannot access file: No such file or directory

Unsure if some of those have to do with the netplan transition

They might (likely to?) be related to libnetplan. I'm looking into it.

Reproducer:
nmcli con add type wifi ifname wlan0 ssid asdasd wifi-sec.key-mgmt wpa-eap 802-1x.eap leap 802-1x.identity username 802-1x.password aaaaaaaa

The crash (SIGABRT) happens in NetworkManager's Netplan integration patch, because of running into a "nm_assert_not_reached()" call. This could easily be avoided by muting that assert and just logging the error and returning FALSE (as is already done below the assert):

https://git.launchpad.net/ubuntu/+source/network-manager/tree/debian/patches/netplan/0002-netplan-make-use-of-libnetplan-for-YAML-backend.patch#n319

This would not fix the root-cause, though, which is located in libnetplan: When creating or updating a NetworkManager connection profile that uses a 802.1x eap authentication method unknown to Netplan (such as "leap" or "pwd"), the Netplan keyfile parser is getting confused and generates a broken keyfile config for NetworkManager.

https://github.com/canonical/netplan/blob/main/src/parse-nm.c#L383

This is triggered when manually adding/modifying a corresponding NM connection profile (through the NM GUI, nmcli, NM DBus, ...) or automatically, when migrating a corresponding profile through NetworkManager's "Netplan everywhere" migration as part of the .postinst maintainer script. In the latter case the crash is handled gracefully, NetworkManager is restarted and the broken keyfile is restored from a backup.

https://git.launchpad.net/ubuntu/+source/network-manager/tree/debian/network-manager.postinst#n67

This can be fixed by supporting all of NetworkManager's 802.1x eap authentication methods in Netplan or by making Netplan's passthrough logic detect such cases and handle them as a fallback.

Kudos to @danilogondolfo for the investigation and the proposed patch:
https://github.com/canonical/netplan/pull/415

I'm working on the SRU of a couple of fixes for Netplan. This ticket is being user for the SRU https://bugs.launchpad.net/ubuntu/+source/netplan.io/+bug/2039825

This bug was fixed in the package netplan.io - 0.107.1-3

---------------
netplan.io (0.107.1-3) unstable; urgency=medium

  * d/t/prep-testbed.sh: Improve autopkgtest reliability
  * d/p/python-limited-stable-api.patch: Build Python module against stable API
    (LP: #2050881)
  * d/patches: Cleanup DEP-3 headers

 -- Lukas Märdian <email address hidden> Tue, 23 Jan 2024 11:13:19 +0100

Can we get proper SRU information on this bug? Thank you!