Users on my computer have all password requesting options enabled, i.e. password is required on waking from suspend, and on returning from blank screen. The screen turns off after few minutes of inactivity and then gets locked.
We want privacy for everybody.
However, it turned out that one can unlock users without entering a password! I found a few scenarios how it can happen (but does not always happen):
- User A clicks the 'Lock / Switch Account`,
or moves away from the computer for a time sufficient to lock the screen.
- Either black screen or greeting with request for a password appears.
(Black screen when switching users is a known problem, see: here and here. To get out of a black screen, we press
Now one would assume that terminal of user A is locked.
- Somebody press
Fncorresponds to user A.
- Console of user A opens. Sometimes it is his greeting with request for a password, but quite often it is just his console without request for a password!
- User A at his console presses
Fncorresponds to user B, and sometimes console of user B opens without password.
There is one user whose account is much more likely can be accessed this way. I tried to change settings for requesting password on his account in various ways, but it did not affect the problem.
There is something else different with this user. His greeting is not like greeting of other users. All greetings show user name and password field on the left side of the screen, as in here, but greeting of easy-breakable user is different: all of the data in the middle of the screen, in different layout, and with button "Switch User". I do not understand where it defined. Can different greeting be connected to the problem of entering without password?
Can it be a bug? Which component is responsible for requesting passwords?
Display manager and it's configuration:
cat /etc/X11/default-display-manager /usr/sbin/lightdm sudo cat /etc/lightdm/lightdm.conf [SeatDefaults] greeter-session=unity-greeter user-session=ubuntu autologin-user= allow-guest=false
graphics card and driver info:
sudo lshw -C video *-display description: VGA compatible controller product: 4th Generation Core Processor Family Integrated Graphics Controller vendor: Intel Corporation physical id: 2 bus info: pci@0000:00:02.0 version: 06 width: 64 bits clock: 33MHz capabilities: msi pm vga_controller bus_master cap_list rom configuration: driver=i915 latency=0 resources: irq:44 memory:f0000000-f03fffff memory:e0000000-efffffff ioport:f000(size=64)