From 983d757f5229f4d885edfc5b0c054fb3e0a73894 Mon Sep 17 00:00:00 2001
From: Yasuhiro Kimura <yasu@utahime.org>
Date: Sun, 23 May 2021 15:34:22 +0900
Subject: [PATCH] textproc/libxml2: Add upstream patch to fix CVE-2021-3541

Add upstream patch to fix CVE-2021-3541.
---
 textproc/libxml2/Makefile                  |  2 +-
 textproc/libxml2/files/patch-CVE-2021-3541 | 67 ++++++++++++++++++++++
 2 files changed, 68 insertions(+), 1 deletion(-)
 create mode 100644 textproc/libxml2/files/patch-CVE-2021-3541

diff --git a/textproc/libxml2/Makefile b/textproc/libxml2/Makefile
index 366bb9f46f5e..749bc604fe4a 100644
--- a/textproc/libxml2/Makefile
+++ b/textproc/libxml2/Makefile
@@ -2,7 +2,7 @@
 
 PORTNAME=	libxml2
 DISTVERSION=	2.9.10
-PORTREVISION?=	3
+PORTREVISION?=	4
 CATEGORIES?=	textproc gnome
 MASTER_SITES=	http://xmlsoft.org/sources/
 DIST_SUBDIR=	gnome2
diff --git a/textproc/libxml2/files/patch-CVE-2021-3541 b/textproc/libxml2/files/patch-CVE-2021-3541
new file mode 100644
index 000000000000..3ba64fa1d967
--- /dev/null
+++ b/textproc/libxml2/files/patch-CVE-2021-3541
@@ -0,0 +1,67 @@
+From 8598060bacada41a0eb09d95c97744ff4e428f8e Mon Sep 17 00:00:00 2001
+From: Daniel Veillard <veillard@redhat.com>
+Date: Thu, 13 May 2021 14:55:12 +0200
+Subject: [PATCH] Patch for security issue CVE-2021-3541
+
+This is relapted to parameter entities expansion and following
+the line of the billion laugh attack. Somehow in that path the
+counting of parameters was missed and the normal algorithm based
+on entities "density" was useless.
+---
+ parser.c | 26 ++++++++++++++++++++++++++
+ 1 file changed, 26 insertions(+)
+
+diff --git parser.c parser.c
+index f5e5e169..c9312fa4 100644
+--- parser.c
++++ parser.c
+@@ -140,6 +140,7 @@ xmlParserEntityCheck(xmlParserCtxtPtr ctxt, size_t size,
+                      xmlEntityPtr ent, size_t replacement)
+ {
+     size_t consumed = 0;
++    int i;
+ 
+     if ((ctxt == NULL) || (ctxt->options & XML_PARSE_HUGE))
+         return (0);
+@@ -177,6 +178,28 @@ xmlParserEntityCheck(xmlParserCtxtPtr ctxt, size_t size,
+ 	    rep = NULL;
+ 	}
+     }
++
++    /*
++     * Prevent entity exponential check, not just replacement while
++     * parsing the DTD
++     * The check is potentially costly so do that only once in a thousand
++     */
++    if ((ctxt->instate == XML_PARSER_DTD) && (ctxt->nbentities > 10000) &&
++        (ctxt->nbentities % 1024 == 0)) {
++	for (i = 0;i < ctxt->inputNr;i++) {
++	    consumed += ctxt->inputTab[i]->consumed +
++	               (ctxt->inputTab[i]->cur - ctxt->inputTab[i]->base);
++	}
++	if (ctxt->nbentities > consumed * XML_PARSER_NON_LINEAR) {
++	    xmlFatalErr(ctxt, XML_ERR_ENTITY_LOOP, NULL);
++	    ctxt->instate = XML_PARSER_EOF;
++	    return (1);
++	}
++	consumed = 0;
++    }
++
++
++
+     if (replacement != 0) {
+ 	if (replacement < XML_MAX_TEXT_LENGTH)
+ 	    return(0);
+@@ -7963,6 +7986,9 @@ xmlParsePEReference(xmlParserCtxtPtr ctxt)
+             xmlChar start[4];
+             xmlCharEncoding enc;
+ 
++	    if (xmlParserEntityCheck(ctxt, 0, entity, 0))
++	        return;
++
+ 	    if ((entity->etype == XML_EXTERNAL_PARAMETER_ENTITY) &&
+ 	        ((ctxt->options & XML_PARSE_NOENT) == 0) &&
+ 		((ctxt->options & XML_PARSE_DTDVALID) == 0) &&
+-- 
+2.31.1
+
-- 
2.31.1