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Description of problem:
If pam_cgroup.so is configured without arguments, it crashes while opening session.

Version-Release number of selected component (if applicable):
libcgroup-0.40.rc1-23.el6

How reproducible:
always

Steps to Reproduce:
$ yum install libcgroup libcgroup-pam openssh-server
$ service cgconfig start
$ service sshd start

# configure sshd to load pam_cgroup.so module without arguments
$ echo "session  optional  pam_cgroup.so" >> /etc/pam.d/sshd

# try to connect to localhost
$ ssh localhost

Actual results:
Write failed: Broken pipe

sshd[5849]: segfault at 0 ip 00007f2a258beac4 sp 00007ffcff89ff10 error 4 in pam_cgroup.so[7f2a258be000+1000]

Expected results:
successful login, no crash

Additional info:
Found originally in bug #1413904.

Created attachment 1248024 [details]
Fixed libcgroup-0.40.rc1-reading-config-files-from-etc-cgconfig.d.patch

Simple workaround is to add an agrument to pam_cgroup.so (any string will prevent the crash, but only "debug" is actually recognized):

session  optional  pam_cgroup.so  debug

The OS license might be $399 or whatever, but the fun of having to reboot a bunch of machines in single user mode to fix pam after applying this update is really priceless.

You knew about this bug more than a month before the broken libcgroup got released in 6.9, and didn't do anything about it? Didn't mark it as a blocker? STILL didn't release a fix for it, 2 months after the busted release? That's just unconscionable.

*** Bug 1465918 has been marked as a duplicate of this bug. ***

@Ion: pam_libcgroup is from the optional channel, I take it RH does not provide the same support here.

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://access.redhat.com/errata/RHBA-2018:1861