File libxml2-2.9.1-CVE-2015-7499.patch of Package python-libxml2.3902

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File libxml2-2.9.1-CVE-2015-7499.patch of Package python-libxml2.3902

From 28cd9cb747a94483f4aea7f0968d202c20bb4cfc Mon Sep 17 00:00:00 2001
From: Daniel Veillard <veillard@redhat.com>
Date: Fri, 20 Nov 2015 14:55:30 +0800
Subject: Add xmlHaltParser() to stop the parser

The problem is doing it in a consistent and safe fashion
It's more complex than just setting ctxt->instate = XML_PARSER_EOF
Update the public function to reuse that new internal routine

From 35bcb1d758ed70aa7b257c9c3b3ff55e54e3d0da Mon Sep 17 00:00:00 2001
From: Daniel Veillard <veillard@redhat.com>
Date: Fri, 20 Nov 2015 15:04:09 +0800
Subject: Detect incoherency on GROW

the current pointer to the input has to be between the base and end
if not stop everything we have an internal state error.

Index: libxml2-2.9.1/parser.c
===================================================================
--- libxml2-2.9.1.orig/parser.c
+++ libxml2-2.9.1/parser.c
@@ -94,6 +94,8 @@ static xmlParserCtxtPtr
 xmlCreateEntityParserCtxtInternal(const xmlChar *URL, const xmlChar *ID,
 	                  const xmlChar *base, xmlParserCtxtPtr pctx);
 
+static void xmlHaltParser(xmlParserCtxtPtr ctxt);
+
 /************************************************************************
  *									*
  *	Arbitrary limits set in the parser. See XML_PARSE_HUGE		*
@@ -2070,9 +2072,16 @@ static void xmlGROW (xmlParserCtxtPtr ct
          ((ctxt->input->buf) && (ctxt->input->buf->readcallback != (xmlInputReadCallback) xmlNop)) &&
         ((ctxt->options & XML_PARSE_HUGE) == 0)) {
         xmlFatalErr(ctxt, XML_ERR_INTERNAL_ERROR, "Huge input lookup");
-        ctxt->instate = XML_PARSER_EOF;
+        xmlHaltParser(ctxt);
+	return;
     }
     xmlParserInputGrow(ctxt->input, INPUT_CHUNK);
+    if ((ctxt->input->cur > ctxt->input->end) ||
+        (ctxt->input->cur < ctxt->input->base)) {
+        xmlHaltParser(ctxt);
+        xmlFatalErr(ctxt, XML_ERR_INTERNAL_ERROR, "cur index out of bound");
+	return;
+    }
     if ((ctxt->input->cur != NULL) && (*ctxt->input->cur == 0) &&
         (xmlParserInputGrow(ctxt->input, INPUT_CHUNK) <= 0))
 	    xmlPopInput(ctxt);
@@ -12542,25 +12551,47 @@ xmlCreatePushParserCtxt(xmlSAXHandlerPtr
 #endif /* LIBXML_PUSH_ENABLED */
 
 /**
- * xmlStopParser:
+ * xmlHaltParser:
  * @ctxt:  an XML parser context
  *
- * Blocks further parser processing
+ * Blocks further parser processing don't override error
+ * for internal use
  */
-void
-xmlStopParser(xmlParserCtxtPtr ctxt) {
+static void
+xmlHaltParser(xmlParserCtxtPtr ctxt) {
     if (ctxt == NULL)
         return;
     ctxt->instate = XML_PARSER_EOF;
-    ctxt->errNo = XML_ERR_USER_STOP;
     ctxt->disableSAX = 1;
     if (ctxt->input != NULL) {
+        /*
+	 * in case there was a specific allocation deallocate before
+	 * overriding base
+	 */
+        if (ctxt->input->free != NULL) {
+	    ctxt->input->free((xmlChar *) ctxt->input->base);
+	    ctxt->input->free = NULL;
+	}
 	ctxt->input->cur = BAD_CAST"";
 	ctxt->input->base = ctxt->input->cur;
     }
 }
 
 /**
+ * xmlStopParser:
+ * @ctxt:  an XML parser context
+ *
+ * Blocks further parser processing
+ */
+void
+xmlStopParser(xmlParserCtxtPtr ctxt) {
+    if (ctxt == NULL)
+        return;
+    xmlHaltParser(ctxt);
+    ctxt->errNo = XML_ERR_USER_STOP;
+}
+
+/**
  * xmlCreateIOParserCtxt:
  * @sax:  a SAX handler
  * @user_data:  The user data returned on SAX callbacks

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File libxml2-2.9.1-CVE-2015-7499.patch of Package python-libxml2.3902

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