785888 – sssd returns empty netgroup at a second request for an non-existing netgroup

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Bug 785888 - sssd returns empty netgroup at a second request for an non-existing netgroup

Summary: sssd returns empty netgroup at a second request for an non-existing netgroup

Keywords:
Status:	CLOSED ERRATA
Alias:	None
Product:	Red Hat Enterprise Linux 6
Classification:	Red Hat
Component:	sssd
Sub Component:
Version:	6.3
Hardware:	Unspecified
OS:	Unspecified
Priority:	unspecified
Severity:	unspecified
Target Milestone:	rc
Target Release:	---
Assignee:	Stephen Gallagher
QA Contact:	IDM QE LIST
Docs Contact:
URL:
Whiteboard:
Depends On:
Blocks:
TreeView+	depends on / blocked

Reported:	2012-01-30 20:27 UTC by Stephen Gallagher
Modified:	2020-05-02 16:19 UTC (History)
CC List:	5 users (show)
Fixed In Version:	sssd-1.8.0-2.el6.beta2
Doc Type:	Bug Fix
Doc Text:	Cause: nss responder uses negative cache to eliminate the need for asking provider for non-existent entity multiple times. However in case of netgroups the querying process didn't work well with the negative cache. Consequence: in some cases an empty netgroup could have been returned to client even if it actually didn't exist Fix: nss responder has been changed to use special flag indicating that the group has been found in the cache instead if using negative cache for netgroup lookups Result: netgroup queries no longer return empty netgroups if they don't exist in the cache
Clone Of:
Environment:
Last Closed:	2012-06-20 11:54:30 UTC
Target Upstream Version:
Embargoed:

Attachments	(Terms of Use)

Links
System	ID	Private	Priority	Status	Summary	Last Updated
Github	SSSD sssd issues 1862	0	None	closed	sssd returns empty netgroup at a second request for an non-existing netgroup	2020-05-02 16:19:13 UTC
Red Hat Product Errata	RHBA-2012:0747	0	normal	SHIPPED_LIVE	sssd bug fix and enhancement update	2012-06-19 19:31:43 UTC

Description Stephen Gallagher 2012-01-30 20:27:26 UTC

This bug is created as a clone of upstream ticket:
https://fedorahosted.org/sssd/ticket/820

The following behaviour can be seen when requesting a non-existing netgroup:

{{{
$ getent netgroup unknown_netgroup
$ getent netgroup unknown_netgroup
unknown_netgroup
}}}

getent netgroup should always return nothing if the netgroup does not exists.

Comment 4 Jan Zeleny 2012-04-04 10:47:25 UTC

    Technical note added. If any revisions are required, please edit the "Technical Notes" field
    accordingly. All revisions will be proofread by the Engineering Content Services team.
    
    New Contents:
Cause: nss responder uses negative cache to eliminate the need for asking provider for non-existent entity multiple times. However in case of netgroups the querying process didn't work well with the negative cache.
Consequence: in some cases an empty netgroup could have been returned to client even if it actually didn't exist
Fix: nss responder has been changed to use special flag indicating that the group has been found in the cache instead if using negative cache for netgroup lookups
Result: netgroup queries no longer return empty netgroups if they don't exist in the cache

Comment 5 Amith 2012-04-11 10:03:36 UTC

Verified on sssd-1.8.0-22.el6.x86_64. 

The output for the associated beaker automation script is given below:

::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
:: [   LOG    ] :: Verify BZ release ticket #336 :- sssd returns empty netgroup at a second request for an non-existing netgroup
::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::

:: [   PASS   ] :: Verify BZ release ticket #336
:: [   PASS   ] :: Verify BZ release ticket #336
:: [   PASS   ] :: Verify BZ release ticket #336
:: [   LOG    ] :: Duration: 14s
:: [   LOG    ] :: Assertions: 6 good, 0 bad
:: [   PASS   ] :: RESULT: Verify BZ release ticket #336 :- sssd returns empty netgroup at a second request for an non-existing netgroup

Comment 7 errata-xmlrpc 2012-06-20 11:54:30 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, and where to find the updated
files, follow the link below.

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

http://rhn.redhat.com/errata/RHBA-2012-0747.html

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