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Bug 636046

Summary:	Disallow 0-sized writes to virtio ports to go through to host (leading to VM crash)
Product:	Red Hat Enterprise Linux 5	Reporter:	Amit Shah <amit.shah>
Component:	kernel	Assignee:	Amit Shah <amit.shah>
Status:	CLOSED ERRATA	QA Contact:	Virtualization Bugs <virt-bugs>
Severity:	medium	Docs Contact:
Priority:	low
Version:	5.6	CC:	amit.shah, llim, tburke, virt-maint
Target Milestone:	rc
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:	635535	Environment:
Last Closed:	2011-01-13 21:21:15 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:	635535
Bug Blocks:	580954

Description Amit Shah 2010-09-21 12:23:45 UTC

Clone to RHEL 5 from the RHEL6 bug

+++ This bug was initially created as a clone of Bug #635535 +++

Description of problem:

The virtio-console code was changed recently such that 0-sized writes go through to the host.  This results in a NULL pointer being passed to qemu, and qemu calling abort() in such a case.

To reproduce, open a console port in the guest and call write() with a 0-sized buffer.

Comment 1 RHEL Program Management 2010-09-21 12:49:11 UTC

This request was evaluated by Red Hat Product Management for inclusion in a Red
Hat Enterprise Linux maintenance release.  Product Management has requested
further review of this request by Red Hat Engineering, for potential
inclusion in a Red Hat Enterprise Linux Update release for currently deployed
products.  This request is not yet committed for inclusion in an Update
release.

Comment 3 Jarod Wilson 2010-10-14 14:03:45 UTC

in kernel-2.6.18-227.el5
You can download this test kernel (or newer) from http://people.redhat.com/jwilson/el5

Detailed testing feedback is always welcomed.

Comment 6 errata-xmlrpc 2011-01-13 21:21:15 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-2011-0017.html