libxml2/SOURCES/RHEL-119283.patch

113 lines
3.5 KiB
Diff

From 677a42645ef22b5a50741bad5facf9d8a8bc6d21 Mon Sep 17 00:00:00 2001
From: Nick Wellnhofer <wellnhofer@aevum.de>
Date: Thu, 28 Jul 2022 20:21:24 +0200
Subject: [PATCH] Make XPath depth check work with recursive invocations
EXSLT functions like dyn:map or dyn:evaluate invoke xmlXPathRunEval
recursively. Don't set depth to zero but keep and restore the original
value to avoid stack overflows when abusing these functions.
---
xpath.c | 23 +++++++++++++++++------
1 file changed, 17 insertions(+), 6 deletions(-)
diff --git a/xpath.c b/xpath.c
index f59ef41d4..4a6f0e216 100644
--- a/xpath.c
+++ b/xpath.c
@@ -13884,12 +13884,11 @@ static int
xmlXPathRunEval(xmlXPathParserContextPtr ctxt, int toBool)
{
xmlXPathCompExprPtr comp;
+ int oldDepth;
if ((ctxt == NULL) || (ctxt->comp == NULL))
return(-1);
- ctxt->context->depth = 0;
-
if (ctxt->valueTab == NULL) {
/* Allocate the value stack */
ctxt->valueTab = (xmlXPathObjectPtr *)
@@ -13943,11 +13942,13 @@ xmlXPathRunEval(xmlXPathParserContextPtr ctxt, int toBool)
"xmlXPathRunEval: last is less than zero\n");
return(-1);
}
+ oldDepth = ctxt->context->depth;
if (toBool)
return(xmlXPathCompOpEvalToBoolean(ctxt,
&comp->steps[comp->last], 0));
else
xmlXPathCompOpEval(ctxt, &comp->steps[comp->last]);
+ ctxt->context->depth = oldDepth;
return(0);
}
@@ -14218,6 +14219,7 @@ xmlXPathCompExprPtr
xmlXPathCtxtCompile(xmlXPathContextPtr ctxt, const xmlChar *str) {
xmlXPathParserContextPtr pctxt;
xmlXPathCompExprPtr comp;
+ int oldDepth = 0;
#ifdef XPATH_STREAMING
comp = xmlXPathTryStreamCompile(ctxt, str);
@@ -14231,8 +14233,10 @@ xmlXPathCtxtCompile(xmlXPathContextPtr ctxt, const xmlChar *str) {
if (pctxt == NULL)
return NULL;
if (ctxt != NULL)
- ctxt->depth = 0;
+ oldDepth = ctxt->depth;
xmlXPathCompileExpr(pctxt, 1);
+ if (ctxt != NULL)
+ ctxt->depth = oldDepth;
if( pctxt->error != XPATH_EXPRESSION_OK )
{
@@ -14253,8 +14257,10 @@ xmlXPathCtxtCompile(xmlXPathContextPtr ctxt, const xmlChar *str) {
comp = pctxt->comp;
if ((comp->nbStep > 1) && (comp->last >= 0)) {
if (ctxt != NULL)
- ctxt->depth = 0;
+ oldDepth = ctxt->depth;
xmlXPathOptimizeExpression(pctxt, &comp->steps[comp->last]);
+ if (ctxt != NULL)
+ ctxt->depth = oldDepth;
}
pctxt->comp = NULL;
}
@@ -14410,6 +14416,7 @@ xmlXPathEvalExpr(xmlXPathParserContextPtr ctxt) {
#ifdef XPATH_STREAMING
xmlXPathCompExprPtr comp;
#endif
+ int oldDepth = 0;
if (ctxt == NULL) return;
@@ -14423,8 +14430,10 @@ xmlXPathEvalExpr(xmlXPathParserContextPtr ctxt) {
#endif
{
if (ctxt->context != NULL)
- ctxt->context->depth = 0;
+ oldDepth = ctxt->context->depth;
xmlXPathCompileExpr(ctxt, 1);
+ if (ctxt->context != NULL)
+ ctxt->context->depth = oldDepth;
CHECK_ERROR;
/* Check for trailing characters. */
@@ -14433,9 +14442,11 @@ xmlXPathEvalExpr(xmlXPathParserContextPtr ctxt) {
if ((ctxt->comp->nbStep > 1) && (ctxt->comp->last >= 0)) {
if (ctxt->context != NULL)
- ctxt->context->depth = 0;
+ oldDepth = ctxt->context->depth;
xmlXPathOptimizeExpression(ctxt,
&ctxt->comp->steps[ctxt->comp->last]);
+ if (ctxt->context != NULL)
+ ctxt->context->depth = oldDepth;
}
}
--
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