sysupgrade is broken

[Rafał Miłecki]

On 21.02.2024 20:52, e9hack wrote:
> root at WLAN-DSL9:~# sysupgrade -b /var/config-backup.tar.gz
> Wed Feb 21 20:48:30 CET 2024 upgrade: Saving config files...
> tar: var/dhcp.leases: No such file or directory
> tar: var/lib/logrotate.status: No such file or directory
> tar: var/log/logrotate.log: No such file or directory
> tar: error exit delayed from previous errors
> Failed to create the configuration backup.

I can reproduce that. The problem is caused by:
mount -t overlay overlay -o lowerdir=/,upperdir="$tmp/upper",workdir="$tmp/work" "$dir"

Apparently lowerdir=/ doesn't work as I expected. In $dir I can see
squashfs + overlay changes but I don't see mounts.

root at OpenWrt:/# ls -l $dir/tmp/
root at OpenWrt:/# ls -l $dir/rom/
-rw-r--r--    1 root     root           116 Feb 19 12:53 note
root at OpenWrt:/# ls -l $dir/dev/
crw-------    1 root     root        5,   1 Feb 19 12:53 console

I'm not sure if there is an easy way to solve that. Anyone?