Bug 1672771

Summary: glibc: Missing robust mutex compiler barriers in pthread_mutex_trylock.c
Product: Red Hat Enterprise Linux 7 Reporter: Carlos O'Donell <codonell>
Component: glibcAssignee: Patsy Griffin <pfrankli>
Status: CLOSED ERRATA QA Contact: qe-baseos-tools-bugs
Severity: unspecified Docs Contact:
Priority: unspecified    
Version: 7.7CC: ashankar, bgollahe, codonell, dj, fweimer, mnewsome, pfrankli, skolosov
Target Milestone: rc   
Target Release: ---   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard:
Fixed In Version: glibc-2.17-297.el7 Doc Type: No Doc Update
Doc Text:
Story Points: ---
Clone Of:
: 1672773 (view as bug list) Environment:
Last Closed: 2020-03-31 19:08:32 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:    
Bug Blocks: 1672773, 1710258    

Description Carlos O'Donell 2019-02-05 21:05:04 UTC 
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 9 Sergey Kolosov 2019-12-04 20:35:32 UTC 
Verified by assembly reviewing
Comment 11 errata-xmlrpc 2020-03-31 19:08:32 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/RHBA-2020:0989