libxml: fix CVE-2021-3517 CVE-2021-3537

(From OE-Core rev: f177c0ec321f005dd9ce63aec2d700fd53c993ff)

Signed-off-by: Lee Chee Yang <chee.yang.lee@intel.com>
Signed-off-by: Steve Sakoman <steve@sakoman.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

3 files changed, 105 insertions, 0 deletions

diff --git a/meta/recipes-core/libxml/libxml2/CVE-2021-3517.patch b/meta/recipes-core/libxml/libxml2/CVE-2021-3517.patch
new file mode 100644
index 0000000000..e88a8ae7c6
--- /dev/null
+++ b/meta/recipes-core/libxml/libxml2/CVE-2021-3517.patch
@@ -0,0 +1,53 @@
+From bf22713507fe1fc3a2c4b525cf0a88c2dc87a3a2 Mon Sep 17 00:00:00 2001
+From: Joel Hockey <joel.hockey@gmail.com>
+Date: Sun, 16 Aug 2020 17:19:35 -0700
+Subject: [PATCH] Validate UTF8 in xmlEncodeEntities
+
+Code is currently assuming UTF-8 without validating. Truncated UTF-8
+input can cause out-of-bounds array access.
+
+Adds further checks to partial fix in 50f06b3e.
+
+Fixes #178
+Upstream-Status: Backport [https://gitlab.gnome.org/GNOME/libxml2/-/commit/bf22713507fe1fc3a2c4b525cf0a88c2dc87a3a2]
+CVE: CVE-2021-3517
+Signed-off-by: Chee Yang Lee <chee.yang.lee@intel.com>
+
+---
+ entities.c | 16 +++++++++++++++-
+ 1 file changed, 15 insertions(+), 1 deletion(-)
+
+diff --git a/entities.c b/entities.c
+index 37b99a56..1a8f86f0 100644
+--- a/entities.c
++++ b/entities.c
+@@ -704,11 +704,25 @@ xmlEncodeEntitiesInternal(xmlDocPtr doc, const xmlChar *input, int attr) {
+            } else {
+                /*
+                 * We assume we have UTF-8 input.
++                * It must match either:
++                *   110xxxxx 10xxxxxx
++                *   1110xxxx 10xxxxxx 10xxxxxx
++                *   11110xxx 10xxxxxx 10xxxxxx 10xxxxxx
++                * That is:
++                *   cur[0] is 11xxxxxx
++                *   cur[1] is 10xxxxxx
++                *   cur[2] is 10xxxxxx if cur[0] is 111xxxxx
++                *   cur[3] is 10xxxxxx if cur[0] is 1111xxxx
++                *   cur[0] is not 11111xxx
+                 */
+                char buf[11], *ptr;
+                int val = 0, l = 1;
+ 
+-               if (*cur < 0xC0) {
++               if (((cur[0] & 0xC0) != 0xC0) ||
++                   ((cur[1] & 0xC0) != 0x80) ||
++                   (((cur[0] & 0xE0) == 0xE0) && ((cur[2] & 0xC0) != 0x80)) ||
++                   (((cur[0] & 0xF0) == 0xF0) && ((cur[3] & 0xC0) != 0x80)) ||
++                   (((cur[0] & 0xF8) == 0xF8))) {
+                    xmlEntitiesErr(XML_CHECK_NOT_UTF8,
+                            "xmlEncodeEntities: input not UTF-8");
+                    if (doc != NULL)
+-- 
+GitLab
+
diff --git a/meta/recipes-core/libxml/libxml2/CVE-2021-3537.patch b/meta/recipes-core/libxml/libxml2/CVE-2021-3537.patch
new file mode 100644
index 0000000000..9e64c2a36d
--- /dev/null
+++ b/meta/recipes-core/libxml/libxml2/CVE-2021-3537.patch
@@ -0,0 +1,50 @@
+From babe75030c7f64a37826bb3342317134568bef61 Mon Sep 17 00:00:00 2001
+From: Nick Wellnhofer <wellnhofer@aevum.de>
+Date: Sat, 1 May 2021 16:53:33 +0200
+Subject: [PATCH] Propagate error in xmlParseElementChildrenContentDeclPriv
+
+Check return value of recursive calls to
+xmlParseElementChildrenContentDeclPriv and return immediately in case
+of errors. Otherwise, struct xmlElementContent could contain unexpected
+null pointers, leading to a null deref when post-validating documents
+which aren't well-formed and parsed in recovery mode.
+
+Fixes #243.
+
+Upstream-Status: Backport
+[https://gitlab.gnome.org/GNOME/libxml2/-/commit/babe75030c7f64a37826bb3342317134568bef61]
+CVE: CVE-2021-3537
+Signed-off-by: Chee Yang Lee <chee.yang.lee@intel.com>
+
+---
+ parser.c | 7 +++++++
+ 1 file changed, 7 insertions(+)
+
+diff --git a/parser.c b/parser.c
+index b42e6043..73c27edd 100644
+--- a/parser.c
++++ b/parser.c
+@@ -6208,6 +6208,8 @@ xmlParseElementChildrenContentDeclPriv(xmlParserCtxtPtr ctxt, int inputchk,
+        SKIP_BLANKS;
+         cur = ret = xmlParseElementChildrenContentDeclPriv(ctxt, inputid,
+                                                            depth + 1);
++        if (cur == NULL)
++            return(NULL);
+        SKIP_BLANKS;
+        GROW;
+     } else {
+@@ -6341,6 +6343,11 @@ xmlParseElementChildrenContentDeclPriv(xmlParserCtxtPtr ctxt, int inputchk,
+            SKIP_BLANKS;
+            last = xmlParseElementChildrenContentDeclPriv(ctxt, inputid,
+                                                           depth + 1);
++            if (last == NULL) {
++               if (ret != NULL)
++                   xmlFreeDocElementContent(ctxt->myDoc, ret);
++               return(NULL);
++            }
+            SKIP_BLANKS;
+        } else {
+            elem = xmlParseName(ctxt);
+-- 
+GitLab
+
diff --git a/meta/recipes-core/libxml/libxml2_2.9.10.bb b/meta/recipes-core/libxml/libxml2_2.9.10.bb
index db660b9869..097613fb28 100644
--- a/meta/recipes-core/libxml/libxml2_2.9.10.bb
+++ b/meta/recipes-core/libxml/libxml2_2.9.10.bb
@@ -23,6 +23,8 @@ SRC_URI = "http://www.xmlsoft.org/sources/libxml2-${PV}.tar.gz;name=libtar \
            file://CVE-2020-7595.patch \
            file://CVE-2019-20388.patch \
            file://CVE-2020-24977.patch \
+           file://CVE-2021-3517.patch \
+           file://CVE-2021-3537.patch \
            "
 
 SRC_URI[libtar.md5sum] = "10942a1dc23137a8aa07f0639cbfece5"