Bug 2025709

Summary:	/etc/profile.d/which2.sh incorrectly tests for ksh (and mksh, zsh) shells
Product:	Red Hat Enterprise Linux 8	Reporter:	tc.staff
Component:	which	Assignee:	Than Ngo <than>
Status:	CLOSED ERRATA	QA Contact:	Jakub Haruda <jharuda>
Severity:	high	Docs Contact:
Priority:	high
Version:	8.5	CC:	bwelterl, byodlows, ccheney, efedin, jcastran, jharuda, mkenjale, ngalvin, prjagtap, rhayden, than
Target Milestone:	rc	Keywords:	CustomerScenariosInitiative, Triaged
Target Release:	8.6
Hardware:	Unspecified
OS:	Linux
Whiteboard:
Fixed In Version:	which-2.21-17.el8	Doc Type:	No Doc Update
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2022-05-10 15:25:05 UTC	Type:	Bug
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Deadline:	2022-01-10

Description tc.staff 2021-11-22 19:26:02 UTC

Description of problem:

/etc/profile.d/which2.sh incorrectly tests for ksh (and mksh, zsh) shells, sets 'declare -f' instead of 'typeset -f'

Version-Release number of selected component (if applicable):

2.21-16.el8


How reproducible:


Steps to Reproduce:
1. create a ksh script that uses #!/usr/bin/ksh
2. run script via cron

Actual results:

When the profiles get run you see

export: -f: unknown option

Expected results:

run script without trying to 'declare -f' in the which2.sh profile

Additional info:

The problem is here -

---
which_shell="$(cat /proc/$$/comm)"

if [ "$which_shell" = "ksh" ] || [ "$which_shell" = "mksh" ] || [ "$which_shell" = "zsh" ] ; then
  which_declare="typeset -f"
  which_opt=""
fi

---

/proc/$$/comm is the name of the command. If the script is "test.ksh" and called
directly it of course doesn't detect a ksh shell, it thinks the shell is "test.ksh".

Is kind of amazing how this passed automated tests? Maybe need to be some new tests.

Comment 4 tc.staff 2021-11-23 20:19:38 UTC

A quick point of clarification: this isn't really cron related. If the script is passed to the interpreter (ksh <script>) then /etc/profile.d/which2.sh will behave as intended. However, if the script is marked as executable and invoked directly (./script) then /proc/$$/comm will contain the name of the script.


=======================
           
$ cat test.ksh
#!/bin/ksh
cat /proc/$$/comm

$ ./test.ksh
test.ksh

$ ksh test.ksh
ksh

=======================

Comment 5 Than Ngo 2021-11-23 21:08:09 UTC

sadly i cannot reproduce your reported issue. It will help me a lot if you can provide working reproduce.

Thanks

Comment 6 tc.staff 2021-11-23 21:15:24 UTC

You bet! 

The steps are below, including reinstalling which (our configuration management automatically replaces the file when it runs).

You'll need to source /etc/profile to invoke /etc/profile.d/which2.sh. You'd do this for non-interactive shells including cron tasks and cluster jobs in certain cases. For example, we use Lmod which requires setup via /etc/profile.d/ files.

Let me know if this helps and if you need any other info.




===================
[jstroik@c8test ~]$ sudo dnf reinstall which
Duo two-factor login for jstroik

...

Reinstalled:
  which-2.21-16.el8.x86_64                                                                                               

Complete!
[jstroik@c8test ~]$ vim test.ksh
[jstroik@c8test ~]$ chmod +x test.ksh
[jstroik@c8test ~]$ cat test.ksh
#!/bin/ksh
echo "about to source /etc/profile"
source /etc/profile
echo "Sourced /etc/profile"

[jstroik@c8test ~]$ ./test.ksh
about to source /etc/profile
./test.ksh[3]: .[70]: .[19]: export: -f: unknown option
Usage: export [-p] [name[=value]...]
Sourced /etc/profile

Comment 7 Than Ngo 2021-11-25 14:56:53 UTC

thanks for the test, i can now reproduce this issue with above steps.
Could you please download https://than.fedorapeople.org/rhel8/which/which-2.21-17.el8.x86_64.rpm and test?

Thanks

Comment 9 tc.staff 2021-11-26 22:35:26 UTC

Yes - I confirm I no longer receive the error. Thank you.

Looking at the updated which2.sh if you have an example script like this:

==============
#!/bin/zsh
source /etc/profile
cat /proc/$$/comm
eval ${which_declare}
==============

You will get different results if you ./test.zsh vs 'zsh test.zsh' due to the way /proc/$$/comm resolves.

Comment 19 Welterlen Benoit 2022-03-21 14:18:07 UTC

*** Bug 2060919 has been marked as a duplicate of this bug. ***

Comment 21 errata-xmlrpc 2022-05-10 15:25:05 UTC

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 (which bug fix and enhancement update), 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-2022:2067