Bug#1143479: networkd: netlink socket overflow during bootup breaking network bridge setup

[Adam Majer]

Package: systemd
Version: 261.1-2
Severity: normal

During bookup, systemd-networkd is listening for netlink events. This socket's
buffer overflows, especially on new kernels that do more things in parallel,

systemd-networkd[1043]: Enumeration completed.
systemd-networkd[1043]: Starting...
systemd-networkd[1043]: Loaded shared library 'libbpf.so.1' via dlopen().
systemd-networkd[1043]: lo: udev initialized link
systemd-networkd[1043]: enp4s0: udev initialized link
systemd-networkd[1043]: Started.
systemd-networkd[1043]: Notify message sent to '/run/systemd/notify': "READY=1\x0aSTATUS=Processing requests..."
systemd-networkd[1043]: sd-device-monitor(n/a): Failed to get the received message size: No buffer space available

... and then network interface is left in "configuring" state forver. Workaround
is to restart systemd-networkd. A solution is to increase buffer size

$ cat /etc/sysctl.d/99_buffers.conf
net.core.rmem_default = 1048576
net.core.rmem_max = 8388608

Packaging solution here would be to increase buffer by default. Alternative,
the systemd-networkd socket could increase its buffer size to not
overflow. Let me know if you wuld like a patch here for systemd instead.

Cheers,
- Adam


-- Package-specific info:

-- System Information:
Debian Release: forky/sid
  APT prefers unstable
  APT policy: (500, 'unstable'), (1, 'experimental')
Architecture: amd64 (x86_64)

Kernel: Linux 7.1.3+deb14-amd64 (SMP w/8 CPU threads; PREEMPT)
Kernel taint flags: TAINT_OOT_MODULE, TAINT_UNSIGNED_MODULE
Locale: LANG=en_CA.UTF-8, LC_CTYPE=en_CA.UTF-8 (charmap=UTF-8), LANGUAGE=en_CA:en
Shell: /bin/sh linked to /usr/bin/dash
Init: systemd (via /run/systemd/system)
LSM: AppArmor: enabled

Versions of packages systemd depends on:
ii  libblkid1          2.42.2-1
ii  libc6              2.42-17
ii  libmount1          2.42.2-1
ii  libsystemd-shared  261.1-2
ii  libsystemd0        261.1-2
ii  mount              2.42.2-1
ii  systemd-tpm        261.1-2

Versions of packages systemd recommends:
ii  dbus [default-dbus-system-bus]   1.16.2-5+b1
ii  libacl1                          2.4.0-1
ii  libbpf1                          1:1.7.0-1
ii  libcryptsetup12                  2:2.8.6-2
ii  libgcrypt20                      1.12.2-1
ii  libpam0g                         1.7.0-7
ii  libseccomp2                      2.6.0-2+b1
ii  libselinux1                      3.10-1
ii  libssl3t64                       3.6.3-1
ii  linux-sysctl-defaults            4.15
ii  login                            1:4.16.0-2+really2.42.2-1
pn  systemd-cryptsetup               <none>
ii  systemd-timesyncd [time-daemon]  261.1-2

Versions of packages systemd suggests:
ii  polkitd            127-3
pn  systemd-boot       <none>
ii  systemd-container  261.1-2
pn  systemd-homed      <none>
pn  systemd-imds       <none>
pn  systemd-repart     <none>
pn  systemd-report     <none>
ii  systemd-resolved   261.1-2
pn  systemd-userdbd    <none>

Versions of packages systemd is related to:
ii  dbus-user-session  1.16.2-5+b1
pn  dracut             <none>
ii  initramfs-tools    0.151
pn  libnss-systemd     <none>
ii  libpam-systemd     261.1-2
ii  udev               261.1-2

-- Configuration Files:
/etc/systemd/logind.conf changed:
[Login]
HandlePowerKey=ignore
HandlePowerKeyLongPress=ignore
HandleRebootKey=ignore
HandleRebootKeyLongPress=ignore


-- no debconf information