I am very impatient, when I unfortunately mistype my login-password on my laptop (Ubuntu 20.04), I don't want to wait three seconds to retry. (A delay of 0.3 seconds would be enough to prevent potential brute force and there is a longer time after 3 failed attempts anyway.)
I found a lot of answers explaining how to change this delay for the console login and for sudo. I managed to set that delay to 0.3 seconds by editing the value in /etc/pam.d/login (for the tty console) to:
auth optional pam_faildelay.so delay=300000
and adding the same line to /etc/pam.d/common-auth (for sudo and the graphical login screen) as first line before (!) this line:
auth [success=1 default=ignore] pam_unix.so nullok_secure nodelay
See:
- Change login timeout when logging in into Ubuntu on stackoverflow
- How can I lower the delay after incorrectly entered login and sudo passwords on askubuntu
This kind of changes the delay that occurs on the graphical gdm3 login-screen in Ubuntu 20.04 but only until the login input field reappears (and shakes). If you set a long delay in /etc/pam.d/common-auth, it counts only for the time before the input field reappears. It has no effect on the delay after the shaking.
I already activated logging in gdm and this is the output of grep gdm3 /var/log/syslog when I pressed SUPER+L to Lock screen and tried about 6 times a false password; you see the 3s delay in the attempt. At the end of each false password attempt, there is a log:
reauthentication service 'gdm-password' stopped
after this there starts the 3s delay until I get a new cursor. Maybe this is the main problem?
Update:
For info: I use GNOME Shell 3.36.1. An Idea of mine was maybe disable the shaking animation will help? Because I found out, that you can use the mouse to click into the field and you can type immmediately while the box is shaking.
