I've tried replicating your setup in a fresh bionic VM (ie. using tmux as default shell which then launches bash) and I can't replicate this:
amurray@sec-bionic-amd64:~$ grep amurray /etc/passwd amurray:x:1000:1000:Ubuntu,,,:/home/amurray:/usr/bin/tmux amurray@sec-bionic-amd64:~$ echo $SHELL /bin/bash amurray@sec-bionic-amd64:~$ cat /etc/tmux.conf set -g default-shell /bin/bash amurray@sec-bionic-amd64:~$ groups amurray adm cdrom sudo dip plugdev lpadmin sambashare This is all from within a graphic gnome-terminal launched after logging into the desktop (see picture which I will attach separately). Can you perhaps try and provide more details on how I could try and replicate this? A couple things to try 1. I've rebuilt polkit-1 with some extra debugging to try and flag when UIDs mismatch - this should end up in the following PPA https://launchpad.net/~alexmurray/+archive/ubuntu/lp1784964 which you could try installing from and seeing if journalctl shows anything? 2. Can you try downgrading polkit-1 and see if that resolves the issue? -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to policykit-1 in Ubuntu. https://bugs.launchpad.net/bugs/1784964 Title: Regression due to CVE-2018-1116 (processes not inheriting user ID or groups ) Status in policykit-1 package in Ubuntu: Confirmed Bug description: This report is tracking a possible regression caused by the recent CVE-2018-1116 patches to policykit-1. On 18.04, since package upgrades on July 23rd, and after the first reboot since then on Aug 1st, I hit an issue with the primary (sudo, adm, etc...) user getting Permission Denied trying to do: tail -f /var/log/syslog when that file is owned by syslog:adm and is g=r. I then found that "groups" reports only the $USER and not the entire list, but "groups $USER" reports all the groups correctly. The user shell is set to /usr/bin/tmux and /etc/tmux.conf has "set -g default-shell /bin/bash" After changing the user's shell back to /bin/bash and logging in on tty1 the list of groups shows correctly for the /bin/bash process running on tty1. I investigated and found that for the affected processes, such as the tmux process, /proc/$PID/loginuid = 4294967295 whereas the /bin/bash process on tty1 correctly reported 1000. The same with the respective gid_map and uid_map. 4294967295 == -1 == 0xFFFFFFFF The recent CVE patch to policykit has several functions where it does "uid = -1" which seems to tie in to my findings so far. I also noticed Ubuntu is still based on version 0.105 which was released in 2012 - upstream released 0.115 with the CVE patch. I suspect the backporting has missed something. The Ubuntu backport patch is: https://git.launchpad.net/ubuntu/+source/policykit-1/commit/?h=applied/ubuntu /bionic-devel&id=840c50182f5ab1ba28c1d20cce4c207364852935 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/policykit-1/+bug/1784964/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp