[sudo-users] strange error for some users on AIX

[Levente Szente]

Hi,

users using kerberos authentication are receiving a strange error message
when trying to run sudo on an AIX box part of a PowerHA cluster:
$ sudo -l
sudo: perm stack underflow: A system call received a parameter that is not
valid.
sudo: unknown uid: 113
Segmentation fault

I have seen in the past the large userid could cause problems, but this is
clearly not the case, the username has only two letters, but on other boxes
is working, so that should also not be a problem.

usrck is not reporting any errors.
Running truss shows that it is able to resolve the uid and the gid, but
nevertheless is bringing the above error message.
The kerberos configuration is the same like on other AIX boxes where sudo
is working.

AIX: 7100-04-01-1543
sudo: 1.8.5p3

Any idea what could be the problem?

Thanks and regards,
Levente