Description of problem:
When I attempt to log into a cinnamon session as a user who normally runs as staff_t I get a "could not connect to session bus" popup and then immediately logged out.  Logging in via the console, switching to permissive, and running ``systemctl --user status dbus.socket'' reveals that dbus failed to listen on the socket it created under /run/user/$UID.  The relevant audit logs are as follows:

type=AVC msg=audit(1516313011.186:655257): avc:  denied  { listen } for  pid=7598 comm="systemd" path="/run/user/1000/bus" scontext=staff_u:staff_r:staff_t:s0-s0:c0.c1023 tcontext=staff_u:staff_r:staff_dbusd_t:s0-s0:c0.c1023 tclass=unix_stream_socket permissive=0
type=SYSCALL msg=audit(1516313011.186:655257): arch=c000003e syscall=50 success=no exit=-13 a0=17 a1=80 a2=15 a3=7ffc293fc15c items=0 ppid=1 pid=7598 auid=1000 uid=1000 gid=100 euid=1000 suid=1000 fsuid=1000 egid=100 sgid=100 fsgid=100 tty=(none) ses=16 comm="systemd" exe="/usr/lib/systemd/systemd" subj=staff_u:staff_r:staff_t:s0-s0:c0.c1023 key=(null)


Version-Release number of selected component (if applicable):
dbus-1.11.20-1.fc27.x86_64
lightdm-1.24.0-1.fc27.x86_64
selinux-policy-3.13.1-283.21.fc27.noarch


How reproducible:
While enforcing and the user has not previously logged in while permissive


Steps to Reproduce:
1.  Install F27 Cinnamon and latest updates
2.  Add a user with a staff_t login
3.  Log in as that user via lightdm


Additional info:
The following policy seems to fix the issue for me:

allow staff_t staff_dbusd_t:unix_stream_socket listen;