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From be24335cbc0019894e6222bd817e717c41550c3c Mon Sep 17 00:00:00 2001
From: Daniel Veillard <veillard@redhat.com>
Date: Mon, 14 Mar 2016 17:19:44 +0800
Subject: [PATCH] Fix inappropriate fetch of entities content
To: libvir-list@redhat.com

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

Signed-off-by: Daniel Veillard <veillard@redhat.com>
---
 parser.c | 16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/parser.c b/parser.c
index 46ab0e8..1936599 100644
--- a/parser.c
+++ b/parser.c
@@ -2854,7 +2854,21 @@ xmlStringLenDecodeEntities(xmlParserCtxtPtr ctxt, const xmlChar *str, int len,
 	        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,
-- 
2.5.5