From 748798889b766bdfe5c13b5afebe732296493a63 Mon Sep 17 00:00:00 2001
From: WuYafeng <yafeng.wu@outlook.com>
Date: Thu, 6 Aug 2020 00:33:31 +0800
Subject: [PATCH] Fix:ControllerLinkGeneratorExtensions.GetAmbientValues throws
 NullReferenceException (#24576)

- related issue #24412
- add null check on GetAmbientValues(HttpContext)
---
 .../Mvc.Core/src/Routing/ControllerLinkGeneratorExtensions.cs   | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/Mvc/Mvc.Core/src/Routing/ControllerLinkGeneratorExtensions.cs b/src/Mvc/Mvc.Core/src/Routing/ControllerLinkGeneratorExtensions.cs
index f0b83af2e6..3c678b025d 100644
--- a/src/Mvc/Mvc.Core/src/Routing/ControllerLinkGeneratorExtensions.cs
+++ b/src/Mvc/Mvc.Core/src/Routing/ControllerLinkGeneratorExtensions.cs
@@ -256,7 +256,7 @@ namespace Microsoft.AspNetCore.Routing
 
         private static RouteValueDictionary GetAmbientValues(HttpContext httpContext)
         {
-            return httpContext?.Features.Get<IRouteValuesFeature>()?.RouteValues;
+            return httpContext?.Features?.Get<IRouteValuesFeature>()?.RouteValues;
         }
     }
 }