Bug 511183

Summary:	kernel: build with -fno-delete-null-pointer-checks [rhel-4.9]
Product:	Red Hat Enterprise Linux 4	Reporter:	Eugene Teo (Security Response) <eteo>
Component:	kernel	Assignee:	Danny Feng <dfeng>
Status:	CLOSED ERRATA	QA Contact:	Evan McNabb <emcnabb>
Severity:	high	Docs Contact:
Priority:	urgent
Version:	4.9	CC:	dhoward, jolsa, jskrabal, lwang, syeghiay, vgoyal
Target Milestone:	rc	Keywords:	ZStream
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:	511181	Environment:
Last Closed:	2011-02-16 15:38:42 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:	511181
Bug Blocks:	517964

Description Eugene Teo (Security Response) 2009-07-14 04:04:17 UTC

+++ This bug was initially created as a clone of Bug #511181 +++

Description of problem:
http://gcc.gnu.org/onlinedocs/gcc-3.4.6/gcc/Optimize-Options.html

-fdelete-null-pointer-checks
    Use global dataflow analysis to identify and eliminate useless checks for null pointers. The compiler assumes that dereferencing a null pointer would have halted the program. If a pointer is checked after it has already been dereferenced, it cannot be null.

    In some environments, this assumption is not true, and programs can safely dereference null pointers. Use -fno-delete-null-pointer-checks to disable this optimization for programs which depend on that behavior.

    Enabled at levels -O2, -O3, -Os.

Comment 3 Eugene Teo (Security Response) 2009-07-17 00:23:29 UTC

Upstream commit:
http://git.kernel.org/linus/a3ca86aea507904148870946d599e07a340b39bf

Comment 7 RHEL Program Management 2009-08-17 15:00:43 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 9 Vivek Goyal 2009-08-19 14:45:39 UTC

Committed in 89.10.EL . RPMS are available at http://people.redhat.com/vgoyal/rhel4/

Comment 13 errata-xmlrpc 2011-02-16 15:38:42 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-2011-0263.html