Bug 503902

Summary:	kernel: TPM: get_event_name stack corruption [mrg-1]
Product:	Red Hat Enterprise MRG	Reporter:	Eugene Teo (Security Response) <eteo>
Component:	realtime-kernel	Assignee:	Red Hat Real Time Maintenance <rt-maint>
Status:	CLOSED ERRATA	QA Contact:	David Sommerseth <davids>
Severity:	high	Docs Contact:
Priority:	high
Version:	Development	CC:	bhu, eparis, eteo, jkacur, jmorris, lgoncalv, ovasik
Target Milestone:	1.1.5
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:
Clones:	503905 504081 (view as bug list)		Environment:
Last Closed:	2009-07-14 19:11:41 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:
Bug Blocks:	503905, 504081

Description Eugene Teo (Security Response) 2009-06-03 09:50:46 UTC

Description of problem:
get_event_name uses sprintf to fill a buffer declared on the stack.  It fills the buffer 2 bytes at a time.  What the code doesn't take into account is that sprintf(buf, "%02x", data) actually writes 3 bytes.  2 bytes for the data and then it nul terminates the string.  Since we declare buf to be 40 characters long and then we write 40 bytes of data into buf sprintf is going to write 41 characters.  The fix is to leave room in buf for the nul terminator.

Upstream commit:
http://git.kernel.org/linus/fbaa58696cef848de818768783ef185bd3f05158

Comment 2 John Kacur 2009-07-01 19:13:19 UTC

Applied to MRG 1.1

Comment 4 David Sommerseth 2009-07-10 15:04:13 UTC

Verified by code review against the 2.6.24.7-126 source tree.  Found upstream commit fbaa58696cef848de818768783ef185bd3f05158 as mrg-rt.git commit 90bbc7f6612e50ae31a0f8b01f34ac66adda2857 (CVS: bz503902_get_event_name_stack_corruption.patch).

Comment 6 errata-xmlrpc 2009-07-14 19:11:41 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-2009-1157.html