Bug 1973030

Summary: [perl-net-ping] wrong return value on failing DNS name lookup
Product: Red Hat Enterprise Linux 8 Reporter: Stefan Meyer <smeyer>
Component: perlAssignee: perl-maint-list
Status: CLOSED ERRATA QA Contact: Martin Kyral <mkyral>
Severity: medium Docs Contact:
Priority: unspecified    
Version: 8.4CC: jplesnik, mkyral
Target Milestone: betaKeywords: Patch, Triaged, ZStream
Target Release: ---   
Hardware: Unspecified   
OS: Unspecified   
Fixed In Version: perl-5.26.3-420.el8 Doc Type: If docs needed, set a value
Doc Text:
Story Points: ---
Clone Of:
: 1973176 1973177 (view as bug list) Environment:
Last Closed: 2021-11-09 19:51:30 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:
Bug Depends On:    
Bug Blocks: 1973176, 1973177    
Description Flags
Replace croak by carp
Fix _resolv return value none

Description Stefan Meyer 2021-06-17 07:05:55 UTC
Description of problem:
The perl-net-ping module delivers the wrong return value on failing DNS name lookup

Version-Release number of selected component (if applicable):
- Tested with perl-Net-Ping-2.55-419.el8.noarch in RHEL 8.4
- Found by a customer on RHEL 8.2

How reproducible:
- With non-existing dns hosts

Steps to Reproduce:
1. install perl-Net-Ping-2.55-419.el8.noarch
2. create example perl script:
   use Net::Ping;
   $ping = Net::Ping->new('tcp');
   $result = $ping->ping('blah.example.com'); # host does not exist in DNS.
   if (defined $result && $result)
      { print "OK\n"; }
      { print "ERROR\n"; }

3. run script

Actual results:
Error message is displayed:
getaddrinfo(blah.lnx.aaxc.org,,AF_INET) failed - Name or service not known at test.pl line 3.

Expected results:
The output should be "ERROR"

Additional info:
Looks like this has been fixed upstream: https://metacpan.org/dist/Net-Ping/changes (line 60)

2.68  Wed Jun 27 11:55:06 CEST 2018 (rurban)
       - Fixed _resolv return value on failing DNS name lookup. (GH #12 nlv02636)

Comment 2 Jitka Plesnikova 2021-06-17 07:39:10 UTC
Thank you for report. I can confirm the issue.

perl-Net-Ping is subpackage of perl.

Comment 3 Jitka Plesnikova 2021-06-17 08:50:53 UTC
These two changes has to be backported to solve the issue. 

2.68  Wed Jun 27 11:55:06 CEST 2018 (rurban)
       - Fixed _resolv return value on failing DNS name lookup. (GH #12 nlv02636)

2.67  Mon Jun 25 18:10:42 CEST 2018 (rurban)
       - Change croak on failing name lookup to return undef,
         matching the documentation.
         Fixes the regression from 2.43, RT #124830

After the fix, final result of the reproducer will be:
# perl bz1973030.pl 
getaddrinfo(blah.example.com,,AF_INET) failed - Name or service not known at /usr/share/perl5/Net/Ping.pm line 1861.

Comment 4 Jitka Plesnikova 2021-06-17 10:08:10 UTC
Created attachment 1791764 [details]
Replace croak by carp

Comment 5 Jitka Plesnikova 2021-06-17 10:09:12 UTC
Created attachment 1791765 [details]
Fix _resolv return value

Comment 13 errata-xmlrpc 2021-11-09 19:51:30 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 (perl 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.