librepo: fix CVE-2020-14352

librepo: missing path validation in repomd.xml may lead to directory traversal

Upstream-Status: Acepted [7daea2a242]
CVE: CVE-2020-14352
(From OE-Core rev: f0df1ff1de6ca9a239d7eafd335b753d6a6e6471)

Signed-off-by: Minjae Kim <flowergom@gmail.com>
Signed-off-by: Steve Sakoman <steve@sakoman.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/recipes-devtools/librepo/librepo/CVE-2020-14352.patch

@@ -0,0 +1,55 @@
+From 6027d68337b537bf9a68cf810cf9b8e40dac22f8 Mon Sep 17 00:00:00 2001
+From: Jaroslav Rohel <jrohel@redhat.com>
+Date: Wed, 12 Aug 2020 08:35:28 +0200
+Subject: [PATCH] Validate path read from repomd.xml (RhBug:1868639)
+
+= changelog =
+msg: Validate path read from repomd.xml
+type: security
+resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1868639
+
+Upstream-Status: Acepted [https://github.com/rpm-software-management/librepo/commit/7daea2a2429a54dad68b1de9b37a5f65c5cf2600]
+CVE: CVE-2020-14352
+Signed-off-by: Minjae Kim <flowergom@gmail.com>
+---
+ librepo/yum.c | 17 +++++++++++++++++
+ 1 file changed, 17 insertions(+)
+
+diff --git a/librepo/yum.c b/librepo/yum.c
+index 3059188..529257b 100644
+--- a/librepo/yum.c
++++ b/librepo/yum.c
+@@ -23,6 +23,7 @@
+ #define  BITS_IN_BYTE 8
+ 
+ #include <stdio.h>
++#include <libgen.h>
+ #include <assert.h>
+ #include <stdlib.h>
+ #include <errno.h>
+@@ -770,6 +771,22 @@ prepare_repo_download_targets(LrHandle *handle,
+             continue;
+ 
+         char *location_href = record->location_href;
++
++        char *dest_dir = realpath(handle->destdir, NULL);
++        path = lr_pathconcat(handle->destdir, record->location_href, NULL);
++        char *requested_dir = realpath(dirname(path), NULL);
++        lr_free(path);
++        if (!g_str_has_prefix(requested_dir, dest_dir)) {
++            g_debug("%s: Invalid path: %s", __func__, location_href);
++            g_set_error(err, LR_YUM_ERROR, LRE_IO, "Invalid path: %s", location_href);
++            g_slist_free_full(*targets, (GDestroyNotify) lr_downloadtarget_free);
++            free(requested_dir);
++            free(dest_dir);
++            return FALSE;
++        }
++        free(requested_dir);
++        free(dest_dir);
++
+         gboolean is_zchunk = FALSE;
+         #ifdef WITH_ZCHUNK
+         if (handle->cachedir && record->header_checksum)
+-- 
+2.17.1
+

meta/recipes-devtools/librepo/librepo_1.11.2.bb

@@ -6,6 +6,7 @@ LIC_FILES_CHKSUM = "file://COPYING;md5=4fbd65380cdd255951079008b364516c"
 SRC_URI = "git://github.com/rpm-software-management/librepo.git \
            file://0002-Do-not-try-to-obtain-PYTHON_INSTALL_DIR-by-running-p.patch \
            file://0004-Set-gpgme-variables-with-pkg-config-not-with-cmake-m.patch \
+           file://CVE-2020-14352.patch \
            "
 
 SRCREV = "67c2d1f83f1bf87be3f26ba730fce7fbdf0c9fba"