libxml2: fix CVE-2020-7595

(From OE-Core rev: f2f7aa9a495774fe5a2e3947584cb3503bd1eaf1)

(From OE-Core rev: 72a747f77f9fd051e054e679deacf537b4b7116f)

Signed-off-by: Anuj Mittal <anuj.mittal@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Anuj Mittal <anuj.mittal@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

2 files changed, 37 insertions, 0 deletions

diff --git a/meta/recipes-core/libxml/libxml2/CVE-2020-7595.patch b/meta/recipes-core/libxml/libxml2/CVE-2020-7595.patch
new file mode 100644
index 0000000000..facfefd362
--- /dev/null
+++ b/meta/recipes-core/libxml/libxml2/CVE-2020-7595.patch
@@ -0,0 +1,36 @@
+From 0e1a49c8907645d2e155f0d89d4d9895ac5112b5 Mon Sep 17 00:00:00 2001
+From: Zhipeng Xie <xiezhipeng1@huawei.com>
+Date: Thu, 12 Dec 2019 17:30:55 +0800
+Subject: [PATCH] Fix infinite loop in xmlStringLenDecodeEntities
+
+When ctxt->instate == XML_PARSER_EOF,xmlParseStringEntityRef
+return NULL which cause a infinite loop in xmlStringLenDecodeEntities
+
+Found with libFuzzer.
+
+Signed-off-by: Zhipeng Xie <xiezhipeng1@huawei.com>
+
+Upstream-Status: Backport [https://gitlab.gnome.org/GNOME/libxml2/commit/0e1a49c89076]
+CVE: CVE-2020-7595
+Signed-off-by: Anuj Mittal <anuj.mittal@intel.com> 
+---
+ parser.c | 3 ++-
+ 1 file changed, 2 insertions(+), 1 deletion(-)
+
+diff --git a/parser.c b/parser.c
+index d1c31963..a34bb6cd 100644
+--- a/parser.c
++++ b/parser.c
+@@ -2646,7 +2646,8 @@ xmlStringLenDecodeEntities(xmlParserCtxtPtr ctxt, const xmlChar *str, int len,
+     else
+         c = 0;
+     while ((c != 0) && (c != end) && /* non input consuming loop */
+-          (c != end2) && (c != end3)) {
++           (c != end2) && (c != end3) &&
++           (ctxt->instate != XML_PARSER_EOF)) {
+ 
+        if (c == 0) break;
+         if ((c == '&') && (str[1] == '#')) {
+-- 
+2.24.1
+
diff --git a/meta/recipes-core/libxml/libxml2_2.9.9.bb b/meta/recipes-core/libxml/libxml2_2.9.9.bb
index c44a90b1c2..5797dd6bee 100644
--- a/meta/recipes-core/libxml/libxml2_2.9.9.bb
+++ b/meta/recipes-core/libxml/libxml2_2.9.9.bb
@@ -21,6 +21,7 @@ SRC_URI = "http://www.xmlsoft.org/sources/libxml2-${PV}.tar.gz;name=libtar \
            file://0001-Make-ptest-run-the-python-tests-if-python-is-enabled.patch \
            file://fix-execution-of-ptests.patch \
            file://Fix-CVE-2019-19956.patch \
+           file://CVE-2020-7595.patch \
            "
 
 SRC_URI[libtar.md5sum] = "c04a5a0a042eaa157e8e8c9eabe76bd6"