[ GLSA 202409-22 ] GCC: Flawed Code Generation

--===============4189637501373381729==
Content-Type: text/plain; charset="utf-8"

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Gentoo Linux Security Advisory                           GLSA 202409-22
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
                                           https://security.gentoo.org/
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

 Severity: Normal
    Title: GCC: Flawed Code Generation
     Date: September 24, 2024
     Bugs: #719466
       ID: 202409-22

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

Synopsis
========

A vulnerability has been discovered in GCC, which can lead to flawed
code generation.

Background
==========

The GNU Compiler Collection includes front ends for C, C++, Objective-C,
Fortran, Ada, Go, D and Modula-2 as well as libraries for these
languages (libstdc++,...).

Affected packages
=================

Package        Vulnerable    Unaffected
-------------  ------------  ------------
sys-devel/gcc  < 10.0        >= 10.0

Description
===========

A vulnerability has been discovered in GCC. Please review the CVE
identifier referenced below for details.

Impact
======

The POWER9 backend in GNU Compiler Collection (GCC) could optimize
multiple calls of the __builtin_darn intrinsic into a single call, thus
reducing the entropy of the random number generator. This occurred
because a volatile operation was not specified. For example, within a
single execution of a program, the output of every __builtin_darn() call
may be the same.

Workaround
==========

There is no known workaround at this time.

Resolution
==========

All GCC users should upgrade to the latest version:

  # emerge --sync
  # emerge --ask --oneshot --verbose ">=sys-devel/gcc-10.0"

And then select it with gcc-config:

  # gcc-config latest

In this case, users should also rebuild all affected packages with
emerge -e, e.g.:

  # emerge --usepkg=n --emptytree @world

References
==========

[ 1 ] CVE-2019-15847
      https://nvd.nist.gov/vuln/detail/CVE-2019-15847

Availability
============

This GLSA and any updates to it are available for viewing at
the Gentoo Security Website:

 https://security.gentoo.org/glsa/202409-22

Concerns?
=========

Security is a primary focus of Gentoo Linux and ensuring the
confidentiality and security of our users' machines is of utmost
importance to us. Any security concerns should be addressed to
[email protected] or alternatively, you may file a bug at
https://bugs.gentoo.org.

License
=======

Copyright 2024 Gentoo Foundation, Inc; referenced text
belongs to its owner(s).

The contents of this document are licensed under the
Creative Commons - Attribution / Share Alike license.

https://creativecommons.org/licenses/by-sa/2.5
--===============4189637501373381729==
Content-Type: application/pgp-signature; name="signature.asc"
Content-Description: OpenPGP digital signature
Content-Disposition: attachment; filename="signature.asc"

-----BEGIN PGP SIGNATURE-----
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=Nw9T
-----END PGP SIGNATURE-----

--===============4189637501373381729==--