[Pkg-utopia-maintainers] Bug#962758: dbus 1.12.18-1 only allows libsane-hpaio to find scanner when root

[Simon McVittie]

Control: tags -1 + moreinfo

On Sat, 13 Jun 2020 at 16:44:41 +0200, Jeffrey Ratcliffe wrote:
> Upgrade from dbus 1.12.16-2 to 1.12.18-1
> 
> scanimage -L
> 
> failed to find my HP OfficeJet 6500

This is unexpected: 1.12.18-1 shouldn't have changed anything related
to authorization or message filtering.

How is your HP OfficeJet 6500 connected/discovered?

After upgrading to 1.12.18-1, did you reboot the system before attempting
to find the scanner? Similarly, when you downgraded back to 1.12.16-2,
did you reboot?

After upgrading to 1.12.18-1 and rebooting, what messages are logged
in the systemd journal when you run "scanimage -L --verbose" as your
ordinary user, and what output does it produce? Also, what messages are
logged and what output does it produce when you run it as root?

Also, if you run "sudo dbus-monitor --system" in another terminal first,
what is logged there in each case? (Press Ctrl+C to exit.)

If you run scanimage -L multiple times as the same user, do you get the
same results each time?

(You can censor log messages and dbus-monitor output as long as you
make it obvious what you've changed, for example replacing MAC addresses
with xx:xx:xx:xx.)

To check that dbus-daemon is operating correctly in general, if you run
"busctl --system" as your ordinary, unprivileged user, do you get a list
of system bus connections?

One important thing that did change in 1.12.18-1 is that the system bus
server now listens on /var/run/dbus/system_bus_socket instead of on
/run/dbus/system_bus_socket. Is /var/run correctly a symbolic link to /run
on your system, and are all the permissions appropriate? It should look
something like this:

$ ls -dl /run /run/dbus /run/dbus/system_bus_socket /var /var/run /var/run/dbus /var/run/dbus/system_bus_socket
drwxr-xr-x 48 root root 1180 Jun 13 16:23 /run
drwxr-xr-x  3 root root   80 Jun 13 14:28 /run/dbus
srw-rw-rw-  1 root root    0 Jun 13 14:28 /run/dbus/system_bus_socket
drwxr-xr-x  1 root root  126 Nov 11  2016 /var
lrwxrwxrwx  1 root root    4 Jun  1  2012 /var/run -> /run
drwxr-xr-x  3 root root   80 Jun 13 14:28 /var/run/dbus
srw-rw-rw-  1 root root    0 Jun 13 14:28 /var/run/dbus/system_bus_socket

    smcv