Package: guix-patches;
Reported by: Ludovic Courtès <ludo <at> gnu.org>
Date: Wed, 26 Jan 2022 11:57:02 UTC
Severity: important
Tags: patch, security
Done: Ludovic Courtès <ludo <at> gnu.org>
Bug is archived. No further changes may be made.
Message #5 received at submit <at> debbugs.gnu.org (full text, mbox):
From: Ludovic Courtès <ludo <at> gnu.org> To: guix-patches <at> gnu.org Cc: Ludovic Courtès <ludo <at> gnu.org> Subject: [PATCH] gnu: polkit: Fix CVE-2021-4034. Date: Wed, 26 Jan 2022 12:56:24 +0100
* gnu/packages/patches/polkit-CVE-2021-4034.patch: New file.
* gnu/local.mk (dist_patch_DATA): Add it.
* gnu/packages/polkit.scm (polkit-mozjs)[replacement]: New field.
* gnu/packages/polkit.scm (polkit-mozjs/fixed): New variable.
---
gnu/local.mk | 1 +
.../patches/polkit-CVE-2021-4034.patch | 82 +++++++++++++++++++
gnu/packages/polkit.scm | 13 ++-
3 files changed, 95 insertions(+), 1 deletion(-)
create mode 100644 gnu/packages/patches/polkit-CVE-2021-4034.patch
Hi!
We could avoid grafting and instead use 'polkit/fixed' in 'setuid-programs',
but it seems safer and less error-prone to graft.
Thoughts?
Ludo'.
diff --git a/gnu/local.mk b/gnu/local.mk
index dceaa53145..eb07842775 100644
--- a/gnu/local.mk
+++ b/gnu/local.mk
@@ -1645,6 +1645,7 @@ dist_patch_DATA = \
%D%/packages/patches/plib-CVE-2011-4620.patch \
%D%/packages/patches/plib-CVE-2012-4552.patch \
%D%/packages/patches/plotutils-spline-test.patch \
+ %D%/packages/patches/polkit-CVE-2021-4034.patch \
%D%/packages/patches/polkit-configure-elogind.patch \
%D%/packages/patches/polkit-use-duktape.patch \
%D%/packages/patches/portaudio-audacity-compat.patch \
diff --git a/gnu/packages/patches/polkit-CVE-2021-4034.patch b/gnu/packages/patches/polkit-CVE-2021-4034.patch
new file mode 100644
index 0000000000..ca766cb3be
--- /dev/null
+++ b/gnu/packages/patches/polkit-CVE-2021-4034.patch
@@ -0,0 +1,82 @@
+Fixes CVE-2021-4034, local privilege escalation with 'pkexec':
+
+ https://www.openwall.com/lists/oss-security/2022/01/25/11
+
+Patch from <https://gitlab.freedesktop.org/polkit/polkit/-/commit/a2bf5c9c83b6ae46cbd5c779d3055bff81ded683>.
+
+From a2bf5c9c83b6ae46cbd5c779d3055bff81ded683 Mon Sep 17 00:00:00 2001
+From: Jan Rybar <jrybar <at> redhat.com>
+Date: Tue, 25 Jan 2022 17:21:46 +0000
+Subject: [PATCH] pkexec: local privilege escalation (CVE-2021-4034)
+
+---
+ src/programs/pkcheck.c | 5 +++++
+ src/programs/pkexec.c | 23 ++++++++++++++++++++---
+ 2 files changed, 25 insertions(+), 3 deletions(-)
+
+diff --git a/src/programs/pkcheck.c b/src/programs/pkcheck.c
+index f1bb4e1..768525c 100644
+--- a/src/programs/pkcheck.c
++++ b/src/programs/pkcheck.c
+@@ -363,6 +363,11 @@ main (int argc, char *argv[])
+ local_agent_handle = NULL;
+ ret = 126;
+
++ if (argc < 1)
++ {
++ exit(126);
++ }
++
+ /* Disable remote file access from GIO. */
+ setenv ("GIO_USE_VFS", "local", 1);
+
+diff --git a/src/programs/pkexec.c b/src/programs/pkexec.c
+index 7698c5c..84e5ef6 100644
+--- a/src/programs/pkexec.c
++++ b/src/programs/pkexec.c
+@@ -488,6 +488,15 @@ main (int argc, char *argv[])
+ pid_t pid_of_caller;
+ gpointer local_agent_handle;
+
++
++ /*
++ * If 'pkexec' is called THIS wrong, someone's probably evil-doing. Don't be nice, just bail out.
++ */
++ if (argc<1)
++ {
++ exit(127);
++ }
++
+ ret = 127;
+ authority = NULL;
+ subject = NULL;
+@@ -614,10 +623,10 @@ main (int argc, char *argv[])
+
+ path = g_strdup (pwstruct.pw_shell);
+ if (!path)
+- {
++ {
+ g_printerr ("No shell configured or error retrieving pw_shell\n");
+ goto out;
+- }
++ }
+ /* If you change this, be sure to change the if (!command_line)
+ case below too */
+ command_line = g_strdup (path);
+@@ -636,7 +645,15 @@ main (int argc, char *argv[])
+ goto out;
+ }
+ g_free (path);
+- argv[n] = path = s;
++ path = s;
++
++ /* argc<2 and pkexec runs just shell, argv is guaranteed to be null-terminated.
++ * /-less shell shouldn't happen, but let's be defensive and don't write to null-termination
++ */
++ if (argv[n] != NULL)
++ {
++ argv[n] = path;
++ }
+ }
+ if (access (path, F_OK) != 0)
+ {
diff --git a/gnu/packages/polkit.scm b/gnu/packages/polkit.scm
index e4f4b1276f..1ae94be751 100644
--- a/gnu/packages/polkit.scm
+++ b/gnu/packages/polkit.scm
@@ -1,7 +1,7 @@
;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2014 Andreas Enge <andreas <at> enge.fr>
;;; Copyright © 2015 Andy Wingo <wingo <at> igalia.com>
-;;; Copyright © 2015, 2021 Ludovic Courtès <ludo <at> gnu.org>
+;;; Copyright © 2015, 2021-2022 Ludovic Courtès <ludo <at> gnu.org>
;;; Copyright © 2015 Mark H Weaver <mhw <at> netris.org>
;;; Copyright © 2016 Efraim Flashner <efraim <at> flashner.co.il>
;;; Copyright © 2017 Huang Ying <huang.ying.caritas <at> gmail.com>
@@ -54,6 +54,7 @@ (define-public polkit-mozjs
(package
(name "polkit")
(version "0.120")
+ (replacement polkit-mozjs/fixed)
(source (origin
(method url-fetch)
(uri (string-append
@@ -146,6 +147,16 @@ (define-public polkit-mozjs
for unprivileged applications.")
(license lgpl2.0+)))
+(define-public polkit-mozjs/fixed
+ (package
+ (inherit polkit-mozjs)
+ (version "0.121")
+ (source (origin
+ (inherit (package-source polkit-mozjs))
+ (patches (cons (search-patch "polkit-CVE-2021-4034.patch")
+ (origin-patches
+ (package-source polkit-mozjs))))))))
+
;;; Variant of polkit built with Duktape, a lighter JavaScript engine compared
;;; to mozjs.
(define-public polkit-duktape
base-commit: 1402c6abe150ced4cbb4fa0721fe7c8796fe2c38
prerequisite-patch-id: 6ecfe5930fe8847a954c16425713d4a6ac515a04
--
2.34.0
GNU bug tracking system
Copyright (C) 1999 Darren O. Benham,
1997,2003 nCipher Corporation Ltd,
1994-97 Ian Jackson.