GLSA 202409-22: GCC: Flawed Code Generation

http://security.gentoo.org/

Severity:	normal
Title:	GCC: Flawed Code Generation
Date:	09/24/2024
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	Architecture(s)
sys-devel/gcc	< 10.0	>= 10.0	ppc, ppc64

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

CVE-2019-15847

Availability

This GLSA and any updates to it are available for viewing at the Gentoo Security Website: http://security.gentoo.org/glsa/glsa-202409-22.xml

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 security@gentoo.org or alternatively, you may file a bug at https://bugs.gentoo.org.