Bug 1122015

Summary: SHM refclock allows only two units with owner-only access
Product: Red Hat Enterprise Linux 6 Reporter: Miroslav Lichvar <mlichvar>
Component: ntpAssignee: Miroslav Lichvar <mlichvar>
Status: CLOSED ERRATA QA Contact: Vaclav Danek <vdanek>
Severity: unspecified Docs Contact:
Priority: unspecified    
Version: 6.6CC: ovasik, psklenar, qe-baseos-daemons, vdanek
Target Milestone: rc   
Target Release: ---   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard:
Fixed In Version: ntp-4.2.6p5-3.el6 Doc Type: Enhancement
Doc Text:
This update introduces configurable access of memory segments used for Shared Memory Driver (SHM) reference clocks. Previously, only the first two memory segments were created with owner-only access, allowing just two SHM reference clocks to be used securely on a system. Now, the owner-only access to SHM is configurable with the "mode" option, and it is therefore possible to use more SHM reference clocks securely.
Story Points: ---
Clone Of: 1122012 Environment:
Last Closed: 2015-07-22 06:59:58 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:
Bug Depends On: 1122012    
Bug Blocks: 1085584, 1159824    

Description Miroslav Lichvar 2014-07-22 11:10:09 UTC
+++ This bug was initially created as a clone of Bug #1122012 +++

Description of problem:
Currently, the permissions of the shared memory segment created by the SHM refclock are set from the unit number. Units 0 and 1 are created with owner-only access, units 2 and above have world access. This is a problem in applications where more units than two are needed and world access would be a security problem.

Upstream bug report with a patch:
http://bugs.ntp.org/show_bug.cgi?id=2627

Version-Release number of selected component (if applicable):
4.2.6p5-18

How reproducible:
Always

Steps to Reproduce:
1. add "server 127.127.28.2" to ntp.conf
2. restart ntpd
3. run ipcs
4. check permission of the memory segment with key 0x4e545032

Actual results:
666

Expected results:
600

Additional info:

Comment 6 errata-xmlrpc 2015-07-22 06:59:58 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.

https://rhn.redhat.com/errata/RHSA-2015-1459.html