Bug 1411306

Summary:	bad performance of snmpd while walk-through ipv6IfDescr if interface index too large
Product:	Red Hat Enterprise Linux 6	Reporter:	Dalibor Pospíšil <dapospis>
Component:	net-snmp	Assignee:	Josef Ridky <jridky>
Status:	CLOSED WONTFIX	QA Contact:	BaseOS QE Security Team <qe-baseos-security>
Severity:	medium	Docs Contact:
Priority:	medium
Version:	6.0	CC:	cww
Target Milestone:	rc
Target Release:	---
Hardware:	Unspecified
OS:	Unspecified
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Clone Of:	1411290
Clones:	1437508 (view as bug list)		Environment:
Last Closed:	2017-06-13 18:35:36 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:

Description Dalibor Pospíšil 2017-01-09 12:13:19 UTC

Description of problem:
This bug is revealed bz fixing bz1396337.
snmpd eatch too much CPU and RAM while processing ipv6IfDescr part of the tree if interface index is too large. It eats more resources as index is larger. This leads to timeout snmpwalk request, the timeout needs to be extend to get the data.

I also get core-dumps at some point, see attachment.

Version-Release number of selected component (if applicable):
net-snmp-5.5-60.el6

How reproducible:
100%

Steps to Reproduce:
1. set manage ifindex to be big enough, e.g. 268435448
2. start snmpd
3. issue snmpbulkwalk -t 15 localhost ipv6IfDescr

Actual results:
snmpbulkwalk times out and snmpd eats up system resources and coredumps

Expected results:
snmpd behaves nicely to system resources and snmpbulkwalk gets all the data

Additional info:

Comment 3 Chris Williams 2017-06-13 18:35:36 UTC

Red Hat Enterprise Linux 6 transitioned to the Production 3 Phase on May 10, 2017.  During the Production 3 Phase, Critical impact Security Advisories (RHSAs) and selected Urgent Priority Bug Fix Advisories (RHBAs) may be released as they become available.
 
The official life cycle policy can be reviewed here:
 
http://redhat.com/rhel/lifecycle
 
This issue does not appear to meet the inclusion criteria for the Production Phase 3 and will be marked as CLOSED/WONTFIX. If this remains a critical requirement, please contact Red Hat Customer Support to request a re-evaluation of the issue, citing a clear business justification.  Red Hat Customer Support can be contacted via the Red Hat Customer Portal at the following URL:
 
https://access.redhat.com