Public bug reported: On Ubuntu 12.04 the pcscd daemon is launched on demand by libpcsclite. I believe it relies on the setgid bit on /usr/sbin/pcscd for the process to gain proper rights to create /var/run/pcscd/pcscd.pid and /var/run/pcscd/pcscd.comm. Ubuntu guest account Apparmor profile prevents setgid bit taking action which means that under guest account it is not possible to use smartcards.
Running pcscd -f as guest user results in: 00000000 pcscdaemon.c:520:main() cannot create /var/run/pcscd/pcscd.pid: Permission denied 00000559 winscard_msg_srv.c:121:InitializeSocket() Unable to bind common socket: Permission denied 00000565 pcscdaemon.c:574:main() Error initializing pcscd. 00000581 pcscdaemon.c:658:clean_temp_files() Cannot remove /var/run/pcscd/pcscd.comm: No such file or directory 00000592 pcscdaemon.c:663:clean_temp_files() Cannot remove /var/run/pcscd/pcscd.pid: No such file or directory 00000604 pcscdaemon.c:658:clean_temp_files() Cannot remove /var/run/pcscd/pcscd.comm: No such file or directory 00000614 pcscdaemon.c:663:clean_temp_files() Cannot remove /var/run/pcscd/pcscd.pid: No such file or directory As regular user it works as expected and card reader is recognized by opensc-tool -l This bug is closely related to #1329923 and actually most of the nature of the problem is described there. As a workaround I have reverted /etc/init.d/pcscd to pre 1.6.0 behaviour by commenting out exit 0 as the file itself suggests by running: sed -i -e 's/^exit 0$/#exit 0/' /etc/init.d/pcscd This just means that the on-demand feature is disabled by launching pcscd during boot and everything works as expected ** Affects: lightdm (Ubuntu) Importance: Undecided Status: New -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1329936 Title: lightdm-guest-session prevents launching pcscd on-demand To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/lightdm/+bug/1329936/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs