diff --git a/92.patch b/92.patch
new file mode 100644
index 0000000..5fc86d9
--- /dev/null
+++ b/92.patch
@@ -0,0 +1,103 @@
+From 4910132853ad68dbe8f4e7710dd098120d1b9b95 Mon Sep 17 00:00:00 2001
+From: Xi Ruoyao <xry111@mengyan1223.wang>
+Date: Tue, 25 Jan 2022 19:19:30 +0800
+Subject: [PATCH 1/3] jsauthority: ensure to call JS_Init() and JS_ShutDown()
+ exactly once
+
+Before this commit, we were calling JS_Init() in
+polkit_backend_js_authority_class_init and never called JS_ShutDown.
+This is actually a misusage of SpiderMonkey API.  Quote from a comment
+in js/Initialization.h (both mozjs-78 and mozjs-91):
+
+    It is currently not possible to initialize SpiderMonkey multiple
+    times (that is, calling JS_Init/JSAPI methods/JS_ShutDown in that
+    order, then doing so again).
+
+This misusage does not cause severe issues with mozjs-78.  However, when
+we eventually port jsauthority to use mozjs-91, bad thing will happen:
+see the test failure mentioned in #150.
+
+This commit is tested with both mozjs-78 and mozjs-91, all tests pass
+with it.
+---
+ src/polkitbackend/polkitbackendjsauthority.cpp | 9 +++++++--
+ 1 file changed, 7 insertions(+), 2 deletions(-)
+
+diff --git a/src/polkitbackend/polkitbackendjsauthority.cpp b/src/polkitbackend/polkitbackendjsauthority.cpp
+index ca17108..b22c34e 100644
+--- a/src/polkitbackend/polkitbackendjsauthority.cpp
++++ b/src/polkitbackend/polkitbackendjsauthority.cpp
+@@ -75,6 +75,13 @@
+
+ /* ---------------------------------------------------------------------------------------------------- */
+
++static class JsInitHelperType
++{
++public:
++	JsInitHelperType() { JS_Init(); }
++	~JsInitHelperType() { JS_ShutDown(); }
++} JsInitHelper;
++
+ struct _PolkitBackendJsAuthorityPrivate
+ {
+   gchar **rules_dirs;
+@@ -589,7 +596,6 @@ polkit_backend_js_authority_finalize (GObject *object)
+   delete authority->priv->js_polkit;
+
+   JS_DestroyContext (authority->priv->cx);
+-  /* JS_ShutDown (); */
+
+   G_OBJECT_CLASS (polkit_backend_js_authority_parent_class)->finalize (object);
+ }
+@@ -666,7 +672,6 @@ polkit_backend_js_authority_class_init (PolkitBackendJsAuthorityClass *klass)
+
+   g_type_class_add_private (klass, sizeof (PolkitBackendJsAuthorityPrivate));
+
+-  JS_Init ();
+ }
+
+ /* ---------------------------------------------------------------------------------------------------- */
+--
+GitLab
+
+
+From 2b5f49a4e4266d2c327ef55e6df121511e23236b Mon Sep 17 00:00:00 2001
+From: Xi Ruoyao <xry111@mengyan1223.wang>
+Date: Tue, 25 Jan 2022 19:20:58 +0800
+Subject: [PATCH 2/3] jsauthority: port to mozjs-91
+
+---
+ configure.ac   | 2 +-
+ meson.build    | 2 +-
+ 2 files changed, 2 insertions(+), 2 deletions(-)
+
+diff --git a/configure.ac b/configure.ac
+index e434ca2..6783ee7 100644
+--- a/configure.ac
++++ b/configure.ac
+@@ -80,7 +80,7 @@ PKG_CHECK_MODULES(GLIB, [gmodule-2.0 gio-unix-2.0 >= 2.30.0])
+ AC_SUBST(GLIB_CFLAGS)
+ AC_SUBST(GLIB_LIBS)
+
+-PKG_CHECK_MODULES(LIBJS, [mozjs-78])
++PKG_CHECK_MODULES(LIBJS, [mozjs-91])
+
+ AC_SUBST(LIBJS_CFLAGS)
+ AC_SUBST(LIBJS_CXXFLAGS)
+--
+diff --git a/meson.build b/meson.build
+index 858078d..09cce0f 100644
+--- a/meson.build
++++ b/meson.build
+@@ -133,7 +133,7 @@ expat_dep = dependency('expat')
+ assert(cc.has_header('expat.h', dependencies: expat_dep), 'Can\'t find expat.h. Please install expat.')
+ assert(cc.has_function('XML_ParserCreate', dependencies: expat_dep), 'Can\'t find expat library. Please install expat.')
+
+-mozjs_dep = dependency('mozjs-78')
++mozjs_dep = dependency('mozjs-91')
+
+ dbus_dep = dependency('dbus-1', required: false)
+ dbus_policydir = pk_prefix / pk_datadir / 'dbus-1/system.d'
+--
+GitLab
+
diff --git a/polkit.spec b/polkit.spec
index efad367..2c1786d 100644
--- a/polkit.spec
+++ b/polkit.spec
@@ -6,7 +6,7 @@
 Summary: An authorization framework
 Name: polkit
 Version: 0.120
-Release: 4%{?dist}
+Release: 5%{?dist}
 License: LGPLv2+
 URL: http://www.freedesktop.org/wiki/Software/polkit
 Source0: http://www.freedesktop.org/software/polkit/releases/%{name}-%{version}.tar.gz
@@ -14,6 +14,8 @@ Source1: http://www.freedesktop.org/software/polkit/releases/%{name}-%{version}.
 
 Patch1: a2bf5c9c83b6ae46cbd5c779d3055bff81ded683.patch
 Patch2: CVE-2021-4115.patch
+# https://gitlab.freedesktop.org/polkit/polkit/-/merge_requests/92
+Patch3: 92.patch
 
 BuildRequires: gcc-c++
 BuildRequires: glib2-devel >= 2.30.0
@@ -23,7 +25,7 @@ BuildRequires: gtk-doc
 BuildRequires: intltool
 BuildRequires: gobject-introspection-devel
 BuildRequires: systemd, systemd-devel
-BuildRequires: pkgconfig(mozjs-78)
+BuildRequires: pkgconfig(mozjs-91)
 BuildRequires: git
 
 %if 0%{?enable_autoreconf}
@@ -177,6 +179,9 @@ exit 0
 %{_libdir}/girepository-1.0/*.typelib
 
 %changelog
+* Sun Feb 20 2022 Frantisek Zatloukal <fzatlouk@redhat.com> - 0.120-5
+- switch to mozjs91
+
 * Wed Feb 16 2022 Jan Rybar <jrybar@redhat.com> - 0.120-4
 - file descriptor exhaustion (GHSL-2021-077)
 - Resolves: CVE-2021-4115