Bug 552757

Summary: unreliable tempfile mechanism in /usr/share/rhn/config_common/file_utils.py
Product: Red Hat Satellite 5 Reporter: Xixi <xdmoon>
Component: Configuration ManagementAssignee: Tomas Lestach <tlestach>
Status: CLOSED ERRATA QA Contact: Dimitar Yordanov <dyordano>
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: cperry, dyordano, mzazrivec, tao, xdmoon
Target Milestone: ---   
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: Bug Fix
Doc Text:
Due to incorrect timing, a temporary file creation may have failed, preventing the configuration file from being deployed. This error has been fixed, and temporary files are now always created as expected.
 Story Points: ---
Clone Of: Environment:
Last Closed: 2010-10-11 14:34:40 UTC Type: ---
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:    
Bug Blocks: 518253    
Attachments:
Description Flags
file_utils.py.patch none

Description Xixi 2010-01-06 02:18:43 UTC 
Description of problem:
maketemp in /usr/share/rhn/config_common/file_utils.py_orig has timing issues.
It constructs tempfiles in a way where it can only have one tempfile per second.
It tries ten times. Fast systems can do this more often and can't create a tempfile.
This happens on fast systems with use of installation profiles (via rhnreg_ks) on RHEL 5 and RHEL 4.

Version-Release number of selected component (if applicable):
Should be independeng of Red Hat Network (RHN) Satellite version, but will check

How reproducible:
Always.

Steps to Reproduce:
1. Try to deploy more than ten config files on a very fast client machine such that that those ten are run in the same second. 

Actual results:
Unable to create tempfile(s)

Expected results:
Successful tempfile creation and config file deployment regardless of how many files user tries to deploy on a fast machine

Additional info:
Customer's using workaround to increase tempfile creation iterations from 10 to 59 in the code.
Comment 1 Xixi 2010-01-06 02:24:23 UTC 
Proposed patch from support is attached - file_utils.py.patch.

It uses tempfile.mkstemp for temp file creation.  If we don't clean up temp files, maybe alternatively consider tempfile.NamedTemporaryFile - however that will delete the file as soon as its closed - or will need to clean it up after use.
Comment 2 Xixi 2010-01-06 02:24:49 UTC 
Created attachment 381901 [details]
file_utils.py.patch
Comment 4 Tomas Lestach 2010-01-14 12:17:53 UTC 
Patch applied with preserving pid as a part of the temp filename.

spacewalk.git: 9a8e2ce1a02b731e915815235520cceae08db1ac
Comment 10 Milan Zázrivec 2010-07-15 16:54:47 UTC 
satellite.git SATELLITE-5.3: f49230a4cc587470509151a837fb61efd1e5de1d
Comment 11 Dimitar Yordanov 2010-08-31 10:04:06 UTC 
From the research and testing I did it turned out that the reason why the bug appeared is the fact that not all systems provide time with a better precision than 1 second.
This has direct impact to the time.time() function that was in use.
In this case the temporary file name format is like /tmp/test_temp-20468-1283174059.
In case the system provides time with a better precision than 1 second the temporary file name is like  "/tmp/test_temp-20463-1283174058.92823195" and the problem does not appear.
In order the issue to be avoided in the fix is used tempfile.mkstemp function that creates temp files in format that does not depend on system time.
Example:
/tmp/test_temp-30533-Ybpw51
/tmp/test_temp-30533-YWJojh
/tmp/test_temp-30533-zxIW0W
/tmp/test_temp-30533-ZyXptw

I tested all the functionality of the  RHN Manager,Client and  Action Control features after the fix was applied (v.5.9.5-6) and I have not found any impact.
Comment 12 Jaromir Hradilek 2010-09-03 15:50:20 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:
Due to incorrect timing, a temporary file creation may have failed, and thus prevent the configuration file from being deployed. This error has been fixed, and temporary files are now always created as expected.
Comment 13 Jaromir Hradilek 2010-09-06 08:19:30 UTC 
    Technical note updated. If any revisions are required, please edit the "Technical Notes" field
    accordingly. All revisions will be proofread by the Engineering Content Services team.
    
    Diffed Contents:
@@ -1 +1 @@
-Due to incorrect timing, a temporary file creation may have failed, and thus prevent the configuration file from being deployed. This error has been fixed, and temporary files are now always created as expected.+Due to incorrect timing, a temporary file creation may have failed, preventing the configuration file from being deployed. This error has been fixed, and temporary files are now always created as expected.
Comment 14 errata-xmlrpc 2010-10-11 14:34:40 UTC 
An advisory has been issued which should help the problem
described in this bug report. This report is therefore being
closed with a resolution of ERRATA. For more information
on therefore solution and/or where to find the updated files,
please follow the link below. You may reopen this bug report
if the solution does not work for you.

http://rhn.redhat.com/errata/RHBA-2010-0761.html