Bug 460858

Summary:	kernel: devmem: add range_is_allowed() check to mmap_mem() [rhel-5.2.z]
Product:	Red Hat Enterprise Linux 5	Reporter:	Eugene Teo (Security Response) <eteo>
Component:	kernel	Assignee:	Jiri Pirko <jpirko>
Status:	CLOSED ERRATA	QA Contact:	Martin Jenner <mjenner>
Severity:	high	Docs Contact:
Priority:	high
Version:	5.2.z	CC:	davej, dhoward, jpirko, lwang, mgahagan, rkhan, security-response-team
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:		Environment:
Last Closed:	2008-11-04 10:30:11 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:	460857
Bug Blocks:

Description Eugene Teo (Security Response) 2008-09-02 04:12:58 UTC

+++ This bug was initially created as a clone of Bug #460857 +++

Description of problem:
Eugene Teo discovered that range_is_allowed() check is only added in {read,write}_mem(). It is possible for an illegitimate application to bypass these checks, and access /dev/mem beyond the 1M limit by calling mmap_mem() instead.

--- Additional comment from eteo on 2008-09-02 00:06:23 EDT ---

phalanx2 rootkit uses mmap to bypass the check, and access /dev/mem between 0 and 8000000.

By adding the range_is_allow() check in mmap_mem(), it is possible to prevent phalanx2 or any other illegitimate application from injecting code into /dev/mem.

 =*=*=*=*=*=*=*=*=*=*=*=*=*=*=
|           phalanx2          |
|       %rebel% . 2008        |
 =*=*=*=*=*=*=*=*=*=*=*=*=*=*=
AUDIT_STATUS: enabled=0 flag=1 pid=4436 rate_limit=0 backlog_limit=320 lost=0 backlog=0
:( could not map memory
 
mmap2(NULL, 134217728, PROT_READ|PROT_WRITE, MAP_SHARED, 3, 0) = -1 EPERM (Operation not permitted)

References:
http://isc.sans.org/diary.html?storyid=4937
http://hep.uchicago.edu/admin/report_072808.html

--- Additional comment from eteo on 2008-09-02 00:07:32 EDT ---

This appears to be fixed in upstream since commit e2beb3eae.

Comment 1 RHEL Program Management 2008-09-02 08:44:02 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 Jiri Pirko 2008-10-13 13:52:42 UTC

in kernel-2.6.18-92.1.15.el5

you can download RPMs from http://people.redhat.com/jpirko/.el52z/92.1.15/

Comment 7 errata-xmlrpc 2008-11-04 10:30:11 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-2008-0957.html