Bug 460858 - kernel: devmem: add range_is_allowed() check to mmap_mem() [rhel-5.2.z]
Summary: kernel: devmem: add range_is_allowed() check to mmap_mem() [rhel-5.2.z]
Keywords:
Status: CLOSED ERRATA
Alias: None
Product: Red Hat Enterprise Linux 5
Classification: Red Hat
Component: kernel
Version: 5.2.z
Hardware: All
OS: Linux
high
high
Target Milestone: rc
: ---
Assignee: Jiri Pirko
QA Contact: Martin Jenner
URL:
Whiteboard:
Depends On: 460857
Blocks:
TreeView+ depends on / blocked
 
Reported: 2008-09-02 04:12 UTC by Eugene Teo (Security Response)
Modified: 2015-05-05 01:15 UTC (History)
7 users (show)

Fixed In Version:
Doc Type: Bug Fix
Doc Text:
Clone Of:
Environment:
Last Closed: 2008-11-04 10:30:11 UTC
Target Upstream Version:
Embargoed:


Attachments (Terms of Use)


Links
System ID Private Priority Status Summary Last Updated
Red Hat Product Errata RHSA-2008:0957 0 normal SHIPPED_LIVE Important: kernel security and bug fix update 2008-11-12 09:34:44 UTC

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


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