Bug#940045: systemd mount command for overlayfs seems incorrect

[Paul Thomas]

Package: systemd
Version: 241-5
Severity: normal

We're trying to create a home.mount file for mounting an overlayfs.
The contents of the file is here:
 [Unit]
 Description=Mount home overlay
 After=mkdirs.service
 Before=local-fs.target

 [Mount]
 Where=/home
 What=overlay
 Type=ovarlay
 Options=lowerdir=/home,upperdir=/tmp/home,workdir=/tmp/home_work

systemd then tries to execute this command:
 /bin/mount overlay /home -t ovarlay -o
lowerdir=/home,upperdir=/tmp/home,workdir=/tmp/home_work
This command fails, it also fails when I try to execute this manually as well.

The correct command should be:
 mount -t overlay overlay -o
lowerdir=/home,upperdir=/tmp/home,workdir=/tmp/home_work /home

Other fs types like tmpfs seem to be fine.

-- Package-specific info:

-- System Information:
Debian Release: 10.0
  APT prefers stable-updates
  APT policy: (500, 'stable-updates'), (500, 'stable')
Architecture: arm64 (aarch64)

Kernel: Linux 5.2.0-rt1-00011-g939b52f8ff17 (SMP w/4 CPU cores; PREEMPT)
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8),
LANGUAGE=en_US.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)

Versions of packages systemd depends on:
ii  adduser          3.118
ii  libacl1          2.2.53-4
ii  libapparmor1     2.13.2-10
ii  libaudit1        1:2.8.4-3
ii  libblkid1        2.33.1-0.1
ii  libc6            2.28-10
ii  libcap2          1:2.25-2
ii  libcryptsetup12  2:2.1.0-5
ii  libgcrypt20      1.8.4-5
ii  libgnutls30      3.6.7-4
ii  libgpg-error0    1.35-1
ii  libidn11         1.33-2.2
ii  libip4tc0        1.8.2-4
ii  libkmod2         26-1
ii  liblz4-1         1.8.3-1
ii  liblzma5         5.2.4-1
ii  libmount1        2.33.1-0.1
ii  libpam0g         1.3.1-5
ii  libseccomp2      2.3.3-4
ii  libselinux1      2.8-1+b1
ii  libsystemd0      241-5
ii  mount            2.33.1-0.1
ii  util-linux       2.33.1-0.1

Versions of packages systemd recommends:
ii  dbus            1.12.16-1
ii  libpam-systemd  241-5

Versions of packages systemd suggests:
pn  policykit-1        <none>
pn  systemd-container  <none>

Versions of packages systemd is related to:
pn  dracut           <none>
pn  initramfs-tools  <none>
ii  udev             241-5

-- no debconf information