libxml2: Fix more NULL pointer derefs

The NULL pointer dereferencing could produced some
security problems.
This is a preventive security fix.

(From OE-Core rev: 8f3008114d5000a0865f50833db7c3a3f9808601)

(From OE-Core rev: 401d552f9e4ed3341e42864e566dddb2b26019dc)

Signed-off-by: Andrej Valek <andrej.valek@siemens.com>
Signed-off-by: Pascal Bach <pascal.bach@siemens.com>
Signed-off-by: Ross Burton <ross.burton@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
Signed-off-by: Armin Kuster <akuster808@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

2 files changed, 47 insertions, 0 deletions

diff --git a/meta/recipes-core/libxml/libxml2/libxml2-fix_NULL_pointer_derefs.patch b/meta/recipes-core/libxml/libxml2/libxml2-fix_NULL_pointer_derefs.patch
new file mode 100644
index 0000000000..83552ca3ec
--- /dev/null
+++ b/meta/recipes-core/libxml/libxml2/libxml2-fix_NULL_pointer_derefs.patch
@@ -0,0 +1,46 @@
+libxml2-2.9.4: Fix more NULL pointer derefs
+
+xpointer: Fix more NULL pointer derefs
+
+Upstream-Status: Backported [https://git.gnome.org/browse/libxml2/commit/?id=e905f08123e4a6e7731549e6f09dadff4cab65bd]
+CVE: -
+Signed-off-by: Andrej Valek <andrej.valek@siemens.com>
+Signed-off-by: Pascal Bach <pascal.bach@siemens.com>
+
+diff --git a/xpointer.c b/xpointer.c
+index 676c510..074db24 100644
+--- a/xpointer.c
++++ b/xpointer.c
+@@ -555,7 +555,7 @@ xmlXPtrNewRangeNodeObject(xmlNodePtr start, xmlXPathObjectPtr end) {
+            /*
+             * Empty set ...
+             */
+-           if (end->nodesetval->nodeNr <= 0)
++           if ((end->nodesetval == NULL) || (end->nodesetval->nodeNr <= 0))
+                return(NULL);
+            break;
+        default:
+@@ -1400,7 +1400,7 @@ xmlXPtrEval(const xmlChar *str, xmlXPathContextPtr ctx) {
+                     */
+                    xmlNodeSetPtr set;
+                    set = tmp->nodesetval;
+-                   if ((set->nodeNr != 1) ||
++                   if ((set == NULL) || (set->nodeNr != 1) ||
+                        (set->nodeTab[0] != (xmlNodePtr) ctx->doc))
+                        stack++;
+                } else
+@@ -2073,9 +2073,11 @@ xmlXPtrRangeFunction(xmlXPathParserContextPtr ctxt, int nargs) {
+        xmlXPathFreeObject(set);
+         XP_ERROR(XPATH_MEMORY_ERROR);
+     }
+-    for (i = 0;i < oldset->locNr;i++) {
+-       xmlXPtrLocationSetAdd(newset,
+-               xmlXPtrCoveringRange(ctxt, oldset->locTab[i]));
++    if (oldset != NULL) {
++       for (i = 0;i < oldset->locNr;i++) {
++         xmlXPtrLocationSetAdd(newset,
++                 xmlXPtrCoveringRange(ctxt, oldset->locTab[i]));
++      }
+     }
+ 
+     /*
diff --git a/meta/recipes-core/libxml/libxml2_2.9.4.bb b/meta/recipes-core/libxml/libxml2_2.9.4.bb
index a1d1e9e12d..ba08c9c994 100644
--- a/meta/recipes-core/libxml/libxml2_2.9.4.bb
+++ b/meta/recipes-core/libxml/libxml2_2.9.4.bb
@@ -22,6 +22,7 @@ SRC_URI = "ftp://xmlsoft.org/libxml2/libxml2-${PV}.tar.gz;name=libtar \
            file://libxml2-fix_node_comparison.patch \
            file://libxml2-CVE-2016-5131.patch \
            file://libxml2-CVE-2016-4658.patch \
+           file://libxml2-fix_NULL_pointer_derefs.patch \
           "
 
 SRC_URI[libtar.md5sum] = "ae249165c173b1ff386ee8ad676815f5"