Commit be2a7eda authored by Daniel Veillard's avatar Daniel Veillard

Fix for CVE-2014-3660

Issues related to the billion laugh entity expansion which happened to
escape the initial set of fixes
parent 500c54ef
......@@ -130,6 +130,29 @@ xmlParserEntityCheck(xmlParserCtxtPtr ctxt, size_t size,
return (0);
if (ctxt->lastError.code == XML_ERR_ENTITY_LOOP)
return (1);
/*
* This may look absurd but is needed to detect
* entities problems
*/
if ((ent != NULL) && (ent->etype != XML_INTERNAL_PREDEFINED_ENTITY) &&
(ent->content != NULL) && (ent->checked == 0)) {
unsigned long oldnbent = ctxt->nbentities;
xmlChar *rep;
ent->checked = 1;
rep = xmlStringDecodeEntities(ctxt, ent->content,
XML_SUBSTITUTE_REF, 0, 0, 0);
ent->checked = (ctxt->nbentities - oldnbent + 1) * 2;
if (rep != NULL) {
if (xmlStrchr(rep, '<'))
ent->checked |= 1;
xmlFree(rep);
rep = NULL;
}
}
if (replacement != 0) {
if (replacement < XML_MAX_TEXT_LENGTH)
return(0);
......@@ -189,9 +212,12 @@ xmlParserEntityCheck(xmlParserCtxtPtr ctxt, size_t size,
return (0);
} else {
/*
* strange we got no data for checking just return
* strange we got no data for checking
*/
return (0);
if (((ctxt->lastError.code != XML_ERR_UNDECLARED_ENTITY) &&
(ctxt->lastError.code != XML_WAR_UNDECLARED_ENTITY)) ||
(ctxt->nbentities <= 10000))
return (0);
}
xmlFatalErr(ctxt, XML_ERR_ENTITY_LOOP, NULL);
return (1);
......@@ -2589,6 +2615,7 @@ xmlParserHandlePEReference(xmlParserCtxtPtr ctxt) {
name, NULL);
ctxt->valid = 0;
}
xmlParserEntityCheck(ctxt, 0, NULL, 0);
} else if (ctxt->input->free != deallocblankswrapper) {
input = xmlNewBlanksWrapperInputStream(ctxt, entity);
if (xmlPushInput(ctxt, input) < 0)
......@@ -2759,6 +2786,7 @@ xmlStringLenDecodeEntities(xmlParserCtxtPtr ctxt, const xmlChar *str, int len,
if ((ctxt->lastError.code == XML_ERR_ENTITY_LOOP) ||
(ctxt->lastError.code == XML_ERR_INTERNAL_ERROR))
goto int_error;
xmlParserEntityCheck(ctxt, 0, ent, 0);
if (ent != NULL)
ctxt->nbentities += ent->checked / 2;
if ((ent != NULL) &&
......@@ -2810,6 +2838,7 @@ xmlStringLenDecodeEntities(xmlParserCtxtPtr ctxt, const xmlChar *str, int len,
ent = xmlParseStringPEReference(ctxt, &str);
if (ctxt->lastError.code == XML_ERR_ENTITY_LOOP)
goto int_error;
xmlParserEntityCheck(ctxt, 0, ent, 0);
if (ent != NULL)
ctxt->nbentities += ent->checked / 2;
if (ent != NULL) {
......@@ -7312,6 +7341,7 @@ xmlParseReference(xmlParserCtxtPtr ctxt) {
(ret != XML_WAR_UNDECLARED_ENTITY)) {
xmlFatalErrMsgStr(ctxt, XML_ERR_UNDECLARED_ENTITY,
"Entity '%s' failed to parse\n", ent->name);
xmlParserEntityCheck(ctxt, 0, ent, 0);
} else if (list != NULL) {
xmlFreeNodeList(list);
list = NULL;
......@@ -7418,7 +7448,7 @@ xmlParseReference(xmlParserCtxtPtr ctxt) {
/*
* We are copying here, make sure there is no abuse
*/
ctxt->sizeentcopy += ent->length;
ctxt->sizeentcopy += ent->length + 5;
if (xmlParserEntityCheck(ctxt, 0, ent, ctxt->sizeentcopy))
return;
......@@ -7466,7 +7496,7 @@ xmlParseReference(xmlParserCtxtPtr ctxt) {
/*
* We are copying here, make sure there is no abuse
*/
ctxt->sizeentcopy += ent->length;
ctxt->sizeentcopy += ent->length + 5;
if (xmlParserEntityCheck(ctxt, 0, ent, ctxt->sizeentcopy))
return;
......@@ -7652,6 +7682,7 @@ xmlParseEntityRef(xmlParserCtxtPtr ctxt) {
ctxt->sax->reference(ctxt->userData, name);
}
}
xmlParserEntityCheck(ctxt, 0, ent, 0);
ctxt->valid = 0;
}
......@@ -7845,6 +7876,7 @@ xmlParseStringEntityRef(xmlParserCtxtPtr ctxt, const xmlChar ** str) {
"Entity '%s' not defined\n",
name);
}
xmlParserEntityCheck(ctxt, 0, ent, 0);
/* TODO ? check regressions ctxt->valid = 0; */
}
......@@ -8004,6 +8036,7 @@ xmlParsePEReference(xmlParserCtxtPtr ctxt)
name, NULL);
ctxt->valid = 0;
}
xmlParserEntityCheck(ctxt, 0, NULL, 0);
} else {
/*
* Internal checking in case the entity quest barfed
......@@ -8243,6 +8276,7 @@ xmlParseStringPEReference(xmlParserCtxtPtr ctxt, const xmlChar **str) {
name, NULL);
ctxt->valid = 0;
}
xmlParserEntityCheck(ctxt, 0, NULL, 0);
} else {
/*
* Internal checking in case the entity quest barfed
......
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