Note: This bug is displayed in read-only format because the product is no longer active in Red Hat Bugzilla.

Bug 1476324

Summary:	md-cache: xattr values should not be checked with string functions
Product:	[Community] GlusterFS	Reporter:	Guenther Deschner <gdeschner>
Component:	md-cache	Assignee:	Guenther Deschner <gdeschner>
Status:	CLOSED CURRENTRELEASE	QA Contact:
Severity:	unspecified	Docs Contact:
Priority:	unspecified
Version:	mainline	CC:	anoopcs, bugs
Target Milestone:	---
Target Release:	---
Hardware:	Unspecified
OS:	Unspecified
Whiteboard:
Fixed In Version:	glusterfs-3.13.0	Doc Type:	If docs needed, set a value
Doc Text:		Story Points:	---
Clone Of:
Clones:	1499892 1499893 (view as bug list)		Environment:
Last Closed:	2017-12-07 05:50:51 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:
Bug Blocks:	1499892, 1499893

Description Guenther Deschner 2017-07-28 15:56:47 UTC

Description of problem:

xattr caching does not work for values with a leading 0 (due to an internal strcmp() for ""), given that often binary values are stored in xattrs (for e.g. samba specific xattrs), this is currently a serious limitation.

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


How reproducible:

Everytime

Steps to Reproduce:

gluster volume set VOLUME performance.cache-samba-metadata on
mount VOLUME via fuse to /mnt
touch /mnt/test
setfattr -n user.DOSATTRIB -v 0x00ff /mnt/test
echo $?
0
getfattr -n user.DOSATTRIB -d /mnt/test
/mnt/test: user.DOSATTRIB: No such attribute

Comment 1 Worker Ant 2017-07-28 15:59:05 UTC

REVIEW: https://review.gluster.org/17910 (md-cache: avoid checking the xattr value buffer with string functions.) posted (#1) for review on master by Günther Deschner (gd)

Comment 2 Worker Ant 2017-07-31 23:23:35 UTC

REVIEW: https://review.gluster.org/17910 (md-cache: avoid checking the xattr value buffer with string functions.) posted (#2) for review on master by Michael Adam (obnox)

Comment 3 Worker Ant 2017-07-31 23:31:26 UTC

REVIEW: https://review.gluster.org/17910 (md-cache: avoid checking the xattr value buffer with string functions.) posted (#3) for review on master by Michael Adam (obnox)

Comment 4 Worker Ant 2017-08-01 13:14:07 UTC

COMMIT: https://review.gluster.org/17910 committed in master by Jeff Darcy (jeff.us) 
------
commit ab4ffdac9dec1867f2d9b33242179cf2b347319d
Author: Günther Deschner <gd>
Date:   Fri Jul 28 13:38:16 2017 +0200

    md-cache: avoid checking the xattr value buffer with string functions.
    
    xattrs may very well contain binary, non-text data with leading 0
    values. Using strcmp for checking empty values is not the appropriate
    thing to do: In the best case, it might treat a binary xattr value
    starting with 0 from being cached (and hence also from being reported
    back with xattr). In the worst case, we might read beyond the end
    of a data blob that does contain any zero byte.
    
    We fix this by checking the length of the data blob and checking
    the first byte against 0 if the length is one.
    
    Signed-off-by: Guenther Deschner <gd>
    Pair-Programmed-With: Michael Adam <obnox>
    Change-Id: If723c465a630b8a37b6be58782a2724df7ac6b11
    BUG: 1476324
    Reviewed-on: https://review.gluster.org/17910
    Reviewed-by: Michael Adam <obnox>
    Smoke: Gluster Build System <jenkins.org>
    Reviewed-by: Poornima G <pgurusid>
    Tested-by: Poornima G <pgurusid>
    CentOS-regression: Gluster Build System <jenkins.org>

Comment 5 Shyamsundar 2017-12-08 17:35:59 UTC

This bug is getting closed because a release has been made available that should address the reported issue. In case the problem is still not fixed with glusterfs-3.13.0, please open a new bug report.

glusterfs-3.13.0 has been announced on the Gluster mailinglists [1], packages for several distributions should become available in the near future. Keep an eye on the Gluster Users mailinglist [2] and the update infrastructure for your distribution.

[1] http://lists.gluster.org/pipermail/announce/2017-December/000087.html
[2] https://www.gluster.org/pipermail/gluster-users/