xref: /third_party/libxml2/backport-malloc-fail-Fix-error-check-in-xmlXPathCompareValues.patch

From 621c222efe87946ad8e53f59e28c782979d340c8 Mon Sep 17 00:00:00 2001
From: Nick Wellnhofer <wellnhofer@aevum.de>
Date: Mon, 30 Jan 2023 15:48:11 +0100
Subject: [PATCH] malloc-fail: Fix error check in xmlXPathCompareValues

Avoid null deref.

Found with libFuzzer, see #344.

Reference:https://github.com/GNOME/libxml2/commit/621c222efe87946ad8e53f59e28c782979d340c8
Conflict:NA
---
 xpath.c | 12 ++----------
 1 file changed, 2 insertions(+), 10 deletions(-)

diff --git a/xpath.c b/xpath.c
index 77d5434..fcbc7e3 100644
--- a/xpath.c
+++ b/xpath.c
@@ -7367,21 +7367,13 @@ xmlXPathCompareValues(xmlXPathParserContextPtr ctxt, int inf, int strict) {
 	valuePush(ctxt, arg1);
 	xmlXPathNumberFunction(ctxt, 1);
 	arg1 = valuePop(ctxt);
-    }
-    if (arg1->type != XPATH_NUMBER) {
-	xmlXPathFreeObject(arg1);
-	xmlXPathFreeObject(arg2);
-	XP_ERROR0(XPATH_INVALID_OPERAND);
+        CHECK_ERROR0;
     }
     if (arg2->type != XPATH_NUMBER) {
 	valuePush(ctxt, arg2);
 	xmlXPathNumberFunction(ctxt, 1);
 	arg2 = valuePop(ctxt);
-    }
-    if (arg2->type != XPATH_NUMBER) {
-	xmlXPathReleaseObject(ctxt->context, arg1);
-	xmlXPathReleaseObject(ctxt->context, arg2);
-	XP_ERROR0(XPATH_INVALID_OPERAND);
+        CHECK_ERROR0;
     }
     /*
      * Add tests for infinity and nan
-- 
2.27.0