I captured this error as it scrolled by during my daily apt routine. I found no evidence in either syslog, kernlog, or dpkglog indicating any failure.
Preconfiguring packages ...
Can't exec "/tmp/samba-common.config.x8y7i8": Permission denied at /usr/share/perl/5.22/IPC/Open3.pm line 178.
open2: exec of /tmp/samba-common.config.x8y7i8 configure 2:4.3.9+dfsg-0ubuntu0.16.04.1 failed at /usr/share/perl5/Debconf/ConfModule.pm line 59.
(Reading database ... 230852 files and directories currently installed.)
...
Setting up samba-libs:amd64 (2:4.3.9+dfsg-0ubuntu0.16.04.2) ...
Setting up python-samba (2:4.3.9+dfsg-0ubuntu0.16.04.2) ...
Setting up samba-common (2:4.3.9+dfsg-0ubuntu0.16.04.2) ...
Setting up samba-common-bin (2:4.3.9+dfsg-0ubuntu0.16.04.2) ...
Setting up libsmbclient:amd64 (2:4.3.9+dfsg-0ubuntu0.16.04.2) ...
I’m not too worried, and beyond my competence level. I’ll wait and see if there’s a repeat of this strangeness.