Comment 8 for bug 234727

Tom,

I discovered the bug reading cron.daily/apt reports, in the same conditions as rafalm.

Until now, I didn't pay attention to those lines (they belong to auth.log):
Sep 10 11:54:31 pc07 sudo: pam_unix(sudo:session): session opened for user fgudin by (uid=0)
Sep 10 11:54:31 pc07 sudo: pam_mount(pam_mount.c:512) error trying to retrieve authtok from auth code

Any command wrapped by "sudo -u another_user " segfaults, *except* when targetted at "-u root".

With these two clues, I tried to disable pam_mount temporarily: bingo! The culprit is the "hooking" of pam_mount.so from /etc/pam.d/common-session, as per:
"session optional pam_mount.so"
Removing this entry alone works around the problem.
I don't know enough about PAM to investigate any further without help, though.

I guess you're also using PAM to mount the homedirs from NFS, aren't you ?

--
Francis