Secure Memory Limitations

OTPClient crashes

When that happens, it's very likely due to secure memory. Most operating systems have sane defaults, while some others have a very low value. For OTPClient, it is suggested to have a memlock limit either greater than 67108864 KB or unlimited. You can check that with ulimit -l, which will show the maximum size of memory, in KB, that can be locked into RAM.

If you execute the program from the terminal, you should see something similar to the following:

couldn't lock 16384 bytes of memory (secret_file_backend): Cannot allocate memory

or

couldn't lock 16384 bytes of memory (secret_session): Impossibile allocare memoria

or

couldn't allocate secure memory

If the same should happen also to you, please before opening an issue here on GitHub try to increase the memlock value by following the steps written below.

How to set memlock

• if pam_limits isn't found in /etc/pam.d/ (from terminal grep -rni pam_limits /etc/pam.d/), append to the file /etc/pam.d/common-session the following text:

session required pam_limits.so

• create a file called, for example, /etc/security/limits.d/memlock.conf and add the following text:

<your_username> soft memlock unlimited
<your_username> hard memlock unlimited

where <your_username> is the username you use to login. You can get that string, for example, by executing whoami from the terminal.

Reboot the system and now ulimit -l should show you unlimited or whatever other value you have chosen.