Bug 2029410

Summary:	glibc: Enabling MAP_32BIT using LD_PREFER_MAP_32BIT_EXEC variable doesn't work
Product:	Red Hat Enterprise Linux 9	Reporter:	Martin Coufal <mcoufal>
Component:	glibc	Assignee:	Florian Weimer <fweimer>
Status:	CLOSED ERRATA	QA Contact:	Sergey Kolosov <skolosov>
Severity:	low	Docs Contact:
Priority:	low
Version:	unspecified	CC:	ashankar, codonell, dj, fweimer, mnewsome, pfrankli, sipoyare, skolosov
Target Milestone:	rc	Keywords:	Bugfix, Patch, Triaged
Target Release:	---
Hardware:	Unspecified
OS:	Unspecified
Whiteboard:
Fixed In Version:	glibc-2.34-13.el9	Doc Type:	No Doc Update
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2022-05-17 15:48:51 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:

Description Martin Coufal 2021-12-06 12:25:51 UTC

Description of problem:
Enabling mmap's MAP_32BIT does not work on rhel-9. See original bug for more details: bz1292018

How reproducible:
100%

Steps to Reproduce:
1. export LD_PREFER_MAP_32BIT_EXEC=1
2. strace -ttt -ff /bin/true |& grep MAP_32BIT


Additional info:
Works on rhel-7, rhel-8.

Comment 1 Florian Weimer 2021-12-06 12:32:47 UTC

The first LOAD segment of system libraries is no longer executable, which disables MAP_32BIT in glibc. This is a result of a binutils change (likely defaulting to -z separate-code).

Comment 3 Florian Weimer 2021-12-10 22:02:02 UTC

Upstream is going to remove this feature. We should backport the change to reduce confusion.

Comment 9 errata-xmlrpc 2022-05-17 15:48:51 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 (new packages: glibc), 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-2022:3917