Bug 1672773

Summary:	glibc: Missing robust mutex compiler barriers in pthread_mutex_trylock.c
Product:	Red Hat Enterprise Linux 8	Reporter:	Carlos O'Donell <codonell>
Component:	glibc	Assignee:	Patsy Griffin <pfrankli>
Status:	CLOSED ERRATA	QA Contact:	qe-baseos-tools-bugs
Severity:	unspecified	Docs Contact:
Priority:	unspecified
Version:	8.0	CC:	ashankar, codonell, dj, fweimer, mcermak, mnewsome, pfrankli, skolosov
Target Milestone:	rc	Keywords:	Patch
Target Release:	8.1	Flags:	pm-rhel: mirror+
Hardware:	Unspecified
OS:	Unspecified
Whiteboard:
Fixed In Version:	glibc-2.28-48.el8	Doc Type:	No Doc Update
Doc Text:		Story Points:	---
Clone Of:	1672771	Environment:
Last Closed:	2019-11-05 21:29:04 UTC	Type:	Bug
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:	1672771, 1682593
Bug Blocks:	1684553, 1701002
Deadline:	2019-04-24

Description Carlos O'Donell 2019-02-05 21:07:11 UTC

+++ This bug was initially created as a clone of Bug #1672771 +++

There are 10 missing compiler barriers in pthread_mutex_trylock.c, which can under certain circumstances, allow an optimizing compiler to reorder stores such that the kernel can observe an inconsistent state in the robust list.

Stefan Liebler's (IBM) patch:
https://www.sourceware.org/ml/libc-alpha/2019-02/msg00129.html

My review:
https://www.sourceware.org/ml/libc-alpha/2019-02/msg00133.html

We should backport this to rhel-7.7, since in rhel-7.6 we did a lot of work to fix other robust mutex issues for the Samba team.

Comment 2 Carlos O'Donell 2019-02-22 19:23:07 UTC

commit 823624bdc47f1f80109c9c52dee7939b9386d708
Author: Stefan Liebler <stli.com>
Date:   Thu Feb 7 15:18:36 2019 +0100

    Add compiler barriers around modifications of the robust mutex list for pthread_mutex_trylock. [BZ #24180]

Comment 7 Sergey Kolosov 2019-09-24 12:31:59 UTC

Verified with objdump based on https://bugzilla.redhat.com/show_bug.cgi?id=1672771#c7 comment, also sanity check that patch was applied.

Comment 9 errata-xmlrpc 2019-11-05 21:29:04 UTC

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://access.redhat.com/errata/RHSA-2019:3513