diff --git a/sdk_container/src/third_party/portage-stable/eclass/readme.gentoo-r1.eclass b/sdk_container/src/third_party/portage-stable/eclass/readme.gentoo-r1.eclass
index dfa3b52b67..0d30217912 100644
--- a/sdk_container/src/third_party/portage-stable/eclass/readme.gentoo-r1.eclass
+++ b/sdk_container/src/third_party/portage-stable/eclass/readme.gentoo-r1.eclass
@@ -1,4 +1,4 @@
-# Copyright 1999-2018 Gentoo Foundation
+# Copyright 1999-2022 Gentoo Authors
 # Distributed under the terms of the GNU General Public License v2
 
 # @ECLASS: readme.gentoo-r1.eclass
@@ -6,7 +6,7 @@
 # Pacho Ramos <pacho@gentoo.org>
 # @AUTHOR:
 # Author: Pacho Ramos <pacho@gentoo.org>
-# @SUPPORTED_EAPIS: 4 5 6 7
+# @SUPPORTED_EAPIS: 6 7 8
 # @BLURB: install a doc file shown via elog messages
 # @DESCRIPTION:
 # An eclass for installing a README.gentoo doc file recording tips
@@ -20,17 +20,16 @@
 if [[ -z ${_README_GENTOO_ECLASS} ]]; then
 _README_GENTOO_ECLASS=1
 
-case "${EAPI:-0}" in
-	0|1|2|3)
-		die "Unsupported EAPI=${EAPI:-0} (too old) for ${ECLASS}"
-		;;
-	4|5|6|7)
-		;;
-	*)
-		die "Unsupported EAPI=${EAPI} (unknown) for ${ECLASS}"
-		;;
+case ${EAPI} in
+	6|7|8) ;;
+	*) die "${ECLASS}: EAPI ${EAPI:-0} not supported" ;;
 esac
 
+# @ECLASS-VARIABLE: DOC_CONTENTS
+# @DEFAULT_UNSET
+# @DESCRIPTION:
+# The information that is used to create the README.gentoo file.
+
 # @ECLASS-VARIABLE: DISABLE_AUTOFORMATTING
 # @DEFAULT_UNSET
 # @DESCRIPTION:
@@ -76,7 +75,10 @@ readme.gentoo_create_doc() {
 		die "You are not specifying README.gentoo contents!"
 	fi
 
-	dodoc "${T}"/README.gentoo
+	( # subshell to avoid pollution of calling environment
+		docinto .
+		dodoc "${T}"/README.gentoo
+	) || die
 	README_GENTOO_DOC_VALUE=$(< "${T}/README.gentoo")
 }