libsane regression error in Ubuntu 20.10: scanner not found

[Francesco V]

I recently update my Kubuntu from 20.04 to

Description: Ubuntu 20.10
Release: 20.10

After the upgrade, it is no longer possible to scan documents using CanoScan N1240U.
lsusb and sane-find-scanner detected the scanner while scanimage, skanlite and xsane cannot found it.
I checked permission, I ran these tools as root, I configured plustek.conf manually but nothing worked.

Finally I rollback libsane, libsane1 and libsane-common from 1.0.31-2 to 1.0.29-0ubuntu5.2 and the scanner is detected out-of-the-box.

[Jouni Mettala (jouni-mettala)]

Did you add your usb vendor and id to plustek.conf?

Did you check /var/lock/sane permissions?

https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=971584

[Francesco V (fsco-v-launchpad)]

Hi, Houni,
really thanks for your help, I workaround to this issue.

Specifying USB in plustek.conf does not fix the issue, suggestion of Pascal Dormeau works for me (https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=971584#57).

$ cat /etc/tmpfiles.d/my-sane-lock.conf
d /var/lock/sane 0775 root scanner - -

I confirm you that this issue is still present, none of this work was requested in 20.04 version.