Bug#946180: Same problem in openssh-server 1:8.4p1-5+deb11u1

Package: openssh-server
Version: 1:8.4p1-5+deb11u1
Followup-For: Bug #946180


Same Problem: All of a sudden, SSH login to one of my Debian 11 
containers fails without obvious reasons. Auth.log shows:


sshd[2058201]: fatal: Missing privilege separation directory: /run/sshd


After creating /var/run/sshd, ssh logins were working again (without 
daemon restart). No problem at the ~30 other machines.


----

-- System Information:
Debian Release: 11.4
   APT prefers stable-updates
   APT policy: (500, 'stable-updates'), (500, 'stable-security'), (500, 
'stable')
Architecture: amd64 (x86_64)

Kernel: Linux 5.15.39-1-pve (SMP w/2 CPU threads)
Kernel taint flags: TAINT_PROPRIETARY_MODULE, TAINT_OOT_MODULE
Locale: LANG=C, LC_CTYPE=C.UTF-8 (charmap=UTF-8), LANGUAGE not set
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)

Versions of packages openssh-server depends on:
ii  adduser                3.118
ii  debconf [debconf-2.0]  1.5.77
ii  dpkg                   1.20.11
ii  libaudit1              1:3.0-2
ii  libc6                  2.31-13+deb11u3
ii  libcom-err2            1.46.2-2
ii  libcrypt1              1:4.4.18-4
ii  libgssapi-krb5-2       1.18.3-6+deb11u1
ii  libkrb5-3              1.18.3-6+deb11u1
ii  libpam-modules         1.4.0-9+deb11u1
ii  libpam-runtime         1.4.0-9+deb11u1
ii  libpam0g               1.4.0-9+deb11u1
ii  libselinux1            3.1-3
ii  libssl1.1              1.1.1n-0+deb11u3
ii  libsystemd0            247.3-7
ii  libwrap0               7.6.q-31
ii  lsb-base               11.1.0
ii  openssh-client         1:8.4p1-5+deb11u1
ii  openssh-sftp-server    1:8.4p1-5+deb11u1
ii  procps                 2:3.3.17-5
ii  runit-helper           2.10.3
ii  ucf                    3.0043
ii  zlib1g                 1:1.2.11.dfsg-2+deb11u1

Versions of packages openssh-server recommends:
ii  libpam-systemd [logind]  247.3-7
ii  ncurses-term             6.2+20201114-2
ii  xauth                    1:1.1-1

Versions of packages openssh-server suggests:
pn  molly-guard   <none>
pn  monkeysphere  <none>
pn  ssh-askpass   <none>
pn  ufw           <none>