File libxml2-2.9.1-CVE-2016-4449.patch of Package libxml2.2672

From b1d34de46a11323fccffa9fadeb33be670d602f5 Mon Sep 17 00:00:00 2001
From: Daniel Veillard <veillard@redhat.com>
Date: Mon, 14 Mar 2016 17:19:44 +0800
Subject: Fix inappropriate fetch of entities content

For https://bugzilla.gnome.org/show_bug.cgi?id=761430

libfuzzer regression testing exposed another case where the parser would
fetch content of an external entity while not in validating mode.
Plug that hole
---
 parser.c | 16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

Index: libxml2-2.9.1/parser.c
===================================================================
--- libxml2-2.9.1.orig/parser.c
+++ libxml2-2.9.1/parser.c
@@ -2837,7 +2837,21 @@ xmlStringLenDecodeEntities(xmlParserCtxt
 	        ctxt->nbentities += ent->checked / 2;
 	    if (ent != NULL) {
                 if (ent->content == NULL) {
-		    xmlLoadEntityContent(ctxt, ent);
+		    /*
+		     * Note: external parsed entities will not be loaded,
+		     * it is not required for a non-validating parser to
+		     * complete external PEreferences coming from the
+		     * internal subset
+		     */
+		    if (((ctxt->options & XML_PARSE_NOENT) != 0) ||
+			((ctxt->options & XML_PARSE_DTDVALID) != 0) ||
+			(ctxt->validate != 0)) {
+			xmlLoadEntityContent(ctxt, ent);
+		    } else {
+			xmlWarningMsg(ctxt, XML_ERR_ENTITY_PROCESSING,
+		  "not validating will not read content for PE entity %s\n",
+		                      ent->name, NULL);
+		    }
 		}
 		ctxt->depth++;
 		rep = xmlStringDecodeEntities(ctxt, ent->content, what,