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colonelx

Member

Registered: 2024-05-19

Posts: 3

[Solved] TTY strange chars

Hello everybody, posting my first question with a strange issue.

I use GDM, u2f pam module. Whenever I jump to TTY and try to login something weird happens:

 login: 

I enter my username and hit enter:

 login: {some valid username} 
^@Password: 

I enter my password and this '^@' does not stop popping out:

 login: {some valid username} 
^@Password: 
^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@

The login is unsuccessful and it does not even ask me to use my u2f key.

Can you please give me an advice where should I start debugging as I am lost.

Last edited by colonelx (2024-05-20 11:43:23)

Trilby

Inspector Parrot

Registered: 2011-11-29

Posts: 30,456

Website

Re: [Solved] TTY strange chars

This has come up a number of times on the forums.  The most likely cause is faulty keyboard input (a stream of null bytes).  If this is not a laptop, try disconnecting / reconnecting any keyboard cables.

Next potential source is video drivers: do you use nvidia by chance?

Some previous examples:
https://bbs.archlinux.org/viewtopic.php?id=230340
https://bbs.archlinux.org/viewtopic.php?id=207359
https://bbs.archlinux.org/viewtopic.php?id=207880
https://bbs.archlinux.org/viewtopic.php?id=258451

Last edited by Trilby (2024-05-19 20:41:50)

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"UNIX is simple and coherent" - Dennis Ritchie; "GNU's Not Unix" - Richard Stallman

colonelx

Member

Registered: 2024-05-19

Posts: 3

Re: [Solved] TTY strange chars

Thank you!
Tried to connect the usb keyboard directly to the usb port on the laptop, rather than via the usb hub and this seemed to fix the issue. I guess I need a new usb hub.