Bug 795813

Summary:	Bad handling of cfa unwind rules in systemtap runtime unwinder
Product:	Red Hat Enterprise Linux 6	Reporter:	Mark Wielaard <mjw>
Component:	systemtap	Assignee:	Frank Ch. Eigler <fche>
Status:	CLOSED DUPLICATE	QA Contact:	qe-baseos-tools-bugs
Severity:	unspecified	Docs Contact:
Priority:	unspecified
Version:	6.3	CC:	mjw, pmuller, scox
Target Milestone:	rc
Target Release:	---
Hardware:	Unspecified
OS:	Unspecified
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2012-02-22 17:20:36 UTC	Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:

Description Mark Wielaard 2012-02-21 15:32:17 UTC

Description of problem:

A sequence of DW_CFA_def_expression followed by a DW_CFA_def_cfa which sets a register rule could make the systemtap runtime unwinder

Version-Release number of selected component (if applicable):

systemtap-1.6-4.el6.x86_64

How reproducible:

Not very. Would take deliberate action to create such a cfa unwind rule. Current rhel6 kernels don't contain any. But fedora kernels do. So the upstream reproducer doesn't currently work. But t would be good to fix in case such sequences do pop up in the future or if user space contains such rules.

Additional info:

Patch attached to upstream bug and already in upstream git. Should not be hard to apply to current rhel systemtap sources.

Comment 4 Vincent Danen 2012-02-22 17:20:36 UTC


*** This bug has been marked as a duplicate of bug 796328 ***