RHEL Engineering is moving the tracking of its product development work on RHEL 6 through RHEL 9 to Red Hat Jira (issues.redhat.com). If you're a Red Hat customer, please continue to file support cases via the Red Hat customer portal. If you're not, please head to the "RHEL project" in Red Hat Jira and file new tickets here. Individual Bugzilla bugs in the statuses "NEW", "ASSIGNED", and "POST" are being migrated throughout September 2023. Bugs of Red Hat partners with an assigned Engineering Partner Manager (EPM) are migrated in late September as per pre-agreed dates. Bugs against components "kernel", "kernel-rt", and "kpatch" are only migrated if still in "NEW" or "ASSIGNED". If you cannot log in to RH Jira, please consult article #7032570. That failing, please send an e-mail to the RH Jira admins at rh-issues@redhat.com to troubleshoot your issue as a user management inquiry. The email creates a ServiceNow ticket with Red Hat. Individual Bugzilla bugs that are migrated will be moved to status "CLOSED", resolution "MIGRATED", and set with "MigratedToJIRA" in "Keywords". The link to the successor Jira issue will be found under "Links", have a little "two-footprint" icon next to it, and direct you to the "RHEL project" in Red Hat Jira (issue links are of type "https://issues.redhat.com/browse/RHEL-XXXX", where "X" is a digit). This same link will be available in a blue banner at the top of the page informing you that that bug has been migrated.

The issue seems to appear also on RHEL7.
+++ This bug was initially created as a clone of Bug #1092877 +++

Description of problem:
The vsftpd hangs when the pam_exec.so is added to the /etc/pam.d/vsftpd.

---------------------------------------------
...
...
session    include	password-auth
session    optional     pam_exec.so /bin/echo
---------------------------------------------

Version-Release number of selected component (if applicable):
vsftpd-3.0.2-9.el7

How reproducible:
always

Steps to Reproduce:
1. add pam_exec.so calling echo to /etc/pam.d/vsftpd
2. add session_support=YES to /etc/vsftpd/vsftpd.conf
3. restart vsftpd
4. connect with a client to the vsftpd
5. login and send e.g. ls command

Actual results:
The vsftpd hangs in SIGCHLD handler

Expected results:
The vsftpd will work as intended.

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://rhn.redhat.com/errata/RHEA-2015-2446.html