Bug 617440

Summary:	guestfish: fails to tilde expand '~' when the $HOME env is unset
Product:	Red Hat Enterprise Linux 6	Reporter:	Jinxin Zheng <jzheng>
Component:	libguestfs	Assignee:	Richard W.M. Jones <rjones>
Status:	CLOSED ERRATA	QA Contact:	Virtualization Bugs <virt-bugs>
Severity:	low	Docs Contact:
Priority:	low
Version:	6.0	CC:	dallan, llim, mbooth, virt-maint, yuzhang
Target Milestone:	rc
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	libguestfs-1.7.17-8.el6	Doc Type:	Bug Fix
Doc Text:	If the $HOME variable was not set, guestfish did not expand a path containing "~" (tilde) into a path to the user's home directory. Guestfish now examines the current user's passwd file for the location of the user's home directory so that a path containing "~" can be expanded correctly. Additionally, an off-by-one error was discovered in the same path-expansion algorithm. This error could potentially cause a crash. The off-by-one error has been corrected so that a crash is no longer possible. (BZ#617440)	Story Points:	---
Clone Of:	617436	Environment:
Last Closed:	2011-05-19 11:45:27 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:	617436
Bug Blocks:

Description Jinxin Zheng 2010-07-23 03:19:05 UTC

Cloning from upstream. As this is not a very severe issue, requesting it to get fixed in 6.1.

+++ This bug was initially created as a clone of Bug #617436 +++

Description of problem:
When the environment variable $HOME is unset, bash can still expand ~ to current user's home path. But guestfish cannot.

Version-Release number of selected component (if applicable):
guestfish-1.2.7-1.18.el6.x86_64

How reproducible:
Always

Steps to Reproduce:

$ unset HOME

$ echo ~
/root

$ guestfish <<EOF
echo ~
EOF
~


Actual results:
~

Expected results:
/root

Additional info:
It would be nice to try expanding ~ from the host's passwd file when HOME is unset.

Comment 1 Richard W.M. Jones 2011-01-04 16:46:13 UTC

Upstream fix:
http://git.annexia.org/?p=libguestfs.git;a=commitdiff;h=7ce627fce02eae8c7db36b4090fa0ce1bf69bf44

Note that while I was fixing this I discovered an off-by-one
bug in related code which should also be backported:
http://git.annexia.org/?p=libguestfs.git;a=commitdiff;h=a9802509184341e731de5c9af363184a9964a8a7

Comment 3 Yufang Zhang 2011-02-15 02:47:33 UTC

QA verified this bug with libguestfs-1.7.17-12.el6.x86_64 and
guestfish-1.7.17-12.el6.x86_64:

# unset HOME

# echo ~
/root

# guestfish

><fs> echo ~
/root

So change this bug to VERIFIED.

Comment 6 Laura Bailey 2011-04-19 01:06:12 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:
If the $HOME variable was not set, guestfish did not expand a path containing "~" (tilde) into a path to the user's home directory (/home/username by default). Guestfish now examines the current user's passwd file for the location of the user's home directory so that a path containing "~" can be expanded correctly.

Additionally, an off-by-one error was discovered in the same path-expansion algorithm. This error could potentially cause a crash if the following command were attempted:

echo 'echo ~root/foo' | guestfish

The off-by-one error has been corrected so that a crash is no longer possible. (BZ#617440)

Comment 7 Richard W.M. Jones 2011-04-19 07:37:07 UTC

Fixed.

Comment 8 Richard W.M. Jones 2011-04-19 07:37:07 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:
@@ -1,7 +1,3 @@
-If the $HOME variable was not set, guestfish did not expand a path containing "~" (tilde) into a path to the user's home directory (/home/username by default). Guestfish now examines the current user's passwd file for the location of the user's home directory so that a path containing "~" can be expanded correctly.
+If the $HOME variable was not set, guestfish did not expand a path containing "~" (tilde) into a path to the user's home directory. Guestfish now examines the current user's passwd file for the location of the user's home directory so that a path containing "~" can be expanded correctly.
 
-Additionally, an off-by-one error was discovered in the same path-expansion algorithm. This error could potentially cause a crash if the following command were attempted:
+Additionally, an off-by-one error was discovered in the same path-expansion algorithm. This error could potentially cause a crash.  The off-by-one error has been corrected so that a crash is no longer possible. (BZ#617440)-
-echo 'echo ~root/foo' | guestfish
-
-The off-by-one error has been corrected so that a crash is no longer possible. (BZ#617440)

Comment 10 errata-xmlrpc 2011-05-19 11:45:27 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-2011-0586.html

Comment 11 errata-xmlrpc 2011-05-19 13:10:23 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-2011-0586.html