Bug 635853 – ptrace: the tracee can get the extra trap after PTRACE_DETACH

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Bug 635853 - ptrace: the tracee can get the extra trap after PTRACE_DETACH

Summary:	ptrace: the tracee can get the extra trap after PTRACE_DETACH

Status:	CLOSED ERRATA

Aliases:	None

Product:	Red Hat Enterprise Linux 6
Classification:	Red Hat
Component:	kernel (Show other bugs)
Sub Component:
Version:	6.1
Hardware:	All Linux

Priority	low Severity low
Target Milestone:	rc
Target Release:	---
Assigned To:	Oleg Nesterov
QA Contact:	Guangze Bai
Docs Contact:

URL:
Whiteboard:
Keywords:

Depends On:
Blocks:
	Show dependency tree / graph

Reported:	2010-09-20 17:59 EDT by Oleg Nesterov
Modified:	2015-02-08 16:36 EST (History)
CC List:	5 users (show)

See Also:
Fixed In Version:	kernel-2.6.32-91.el6
Doc Type:	Bug Fix
Doc Text:
Story Points:	---
Clone Of:
Environment:
Last Closed:	2011-05-23 16:53:02 EDT
Type:	---
Regression:	---
Mount Type:	---
Documentation:	---
CRM:
Verified Versions:
Category:	---
oVirt Team:	---
RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---

Attachments	(Terms of Use)
the tracee gets the extra trap after PTRACE_DETACH (723 bytes, text/plain) 2010-09-20 17:59 EDT, Oleg Nesterov	no flags	Details
Add an attachment (proposed patch, testcase, etc.)

External Trackers
Tracker	ID	Priority	Status	Summary	Last Updated
Red Hat Product Errata	RHSA-2011:0542	normal	SHIPPED_LIVE	Important: Red Hat Enterprise Linux 6.1 kernel security, bug fix and enhancement update	2011-05-19 07:58:07 EDT

Groups: None (edit)

Description Oleg Nesterov 2010-09-20 17:59:37 EDT

Created attachment 448556 [details]
the tracee gets the extra trap after PTRACE_DETACH

Description of problem:

TIF_SINGLESTEP is not cleared after PTRACE_DETACH
and the tracee gets another trap after resume.

How reproducible:

    always

Steps to Reproduce:

    run the attached test-case

Actual results:

    the tracee gets the trap after detach

Expected results:

    the tracee should exit normaly

Additional info:

    the patch exists, under discussion

Comment 2 RHEL Product and Program Management 2010-11-10 07:19:51 EST

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 Oleg Nesterov 2010-11-24 12:45:00 EST

[RHEL6.1 PATCH] bz635853: utrace: move user_disable_single_step() logic from utrace_control() to utrace_reset()
http://post-office.corp.redhat.com/archives/rhkernel-list/2010-November/msg01359.html

Comment 4 Aristeu Rozanski 2010-12-15 11:06:44 EST

Patch(es) available on kernel-2.6.32-91.el6

Comment 9 Guangze Bai 2011-04-26 23:25:00 EDT

Having run attachment,reproduced on kernel-2.6.32-85.el6:

# ./a.out
ERR!! exit status: 0085

verified on kernel-2.6.32-122.el6:

# ./a.out
# echo $?
0
(exit normally)

Comment 10 errata-xmlrpc 2011-05-23 16:53:02 EDT

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-2011-0542.html

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