Bug 648408

Summary:	Do not mix FMODE_ and O_ flags with break_lease() and may_open() [rhel-6.0.z]
Product:	Red Hat Enterprise Linux 6	Reporter:	RHEL Program Management <pm-rhel>
Component:	kernel	Assignee:	Frantisek Hrbata <fhrbata>
Status:	CLOSED ERRATA	QA Contact:	yanfu,wang <yanwang>
Severity:	high	Docs Contact:
Priority:	high
Version:	6.0	CC:	bfields, dhoward, harshula, jlayton, kzhang, moshiro, myamazak, pm-eus, steved
Target Milestone:	rc	Keywords:	Regression, ZStream
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	kernel-2.6.32-71.9.1.el6	Doc Type:	Bug Fix
Doc Text:	Due to a mix-up between FMODE_ and O_ flags, an NFSv4 client could get a WRITE lock on a file that another NFSv4 client already had a READ lock on. As a result, data could be corrupted. With this update, FMODE_ and O_ flags are properly handled and getting a WRITE lock fails in the aforementioned case.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2011-01-11 19:47:45 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:	642677, 1020741
Bug Blocks:

Description RHEL Program Management 2010-11-01 08:36:24 UTC

This bug has been copied from bug #642677 and has been proposed
to be backported to 6.0 z-stream (EUS).

Comment 3 Frantisek Hrbata 2010-11-22 07:53:51 UTC

in kernel-2.6.32-71.9.1.el6

Comment 5 yanfu,wang 2010-12-15 08:41:14 UTC

reproduced on rhel6-rc4 got the same error as per https://bugzilla.redhat.com/show_bug.cgi?id=642677#c0
verified on kernel-2.6.32-71.13.1.el6 on i386 and x86_64, result passed.
server:
# ./delegation /mnt
Step1: Get READ DELEGATION
       Get Success:(/mnt/file)
Step2: Get a READ lock
       Get READ lock success.
            <== Let the program pending here, goto STEP2
Step3: Release the READ lock
       Release READ lock success.
Step4: Close file

client:
# ./lock /mnttest/file 
Step1: Open file with O_RDWR
       Open Success:(/mnttest/file)
Step2: Get a WRITE lock
ERROR: Get WRITE lock fail
Step4: Close file

Comment 7 errata-xmlrpc 2011-01-11 19:47:45 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/RHSA-2011-0007.html

Comment 8 Martin Prpič 2011-01-12 12:54:19 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 a mix-up between FMODE_ and O_ flags, an NFSv4 client could get a WRITE lock on a file that another NFSv4 client already had a READ lock on. As a result, data could be corrupted. With this update, FMODE_ and O_ flags are properly handled and getting a WRITE lock fails in the aforementioned case.