From 0a4a625158439004b7386f65d805fd9a02f350e9 Mon Sep 17 00:00:00 2001
From: nayang7 <107023695+nayang7@users.noreply.github.com>
Date: Fri, 29 Jul 2022 13:36:19 +0800
Subject: [PATCH] Fix Remote IP Address - NULL reference exception (#3481)

---
 src/OpenTelemetry.Instrumentation.AspNetCore/CHANGELOG.md   | 2 ++
 .../Implementation/HttpInListener.cs                        | 6 +++++-
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/src/OpenTelemetry.Instrumentation.AspNetCore/CHANGELOG.md b/src/OpenTelemetry.Instrumentation.AspNetCore/CHANGELOG.md
index 241df1ee7f8..d456038b9b8 100644
--- a/src/OpenTelemetry.Instrumentation.AspNetCore/CHANGELOG.md
+++ b/src/OpenTelemetry.Instrumentation.AspNetCore/CHANGELOG.md
@@ -2,6 +2,8 @@
 
 ## Unreleased
 
+* Fix Remote IP Address - NULL reference exception.
+  ([#3481](https://github.com/open-telemetry/opentelemetry-dotnet/pull/3481))
 * Metrics instrumentation to correctly populate `http.flavor` tag.
   (1.1 instead of HTTP/1.1 etc.)
   ([#3379](https://github.com/open-telemetry/opentelemetry-dotnet/pull/3379))
diff --git a/src/OpenTelemetry.Instrumentation.AspNetCore/Implementation/HttpInListener.cs b/src/OpenTelemetry.Instrumentation.AspNetCore/Implementation/HttpInListener.cs
index 1ff80acc8b2..a37863ad8b9 100644
--- a/src/OpenTelemetry.Instrumentation.AspNetCore/Implementation/HttpInListener.cs
+++ b/src/OpenTelemetry.Instrumentation.AspNetCore/Implementation/HttpInListener.cs
@@ -360,7 +360,11 @@ private static void AddGrpcAttributes(Activity activity, string grpcMethod, Http
             activity.DisplayName = grpcMethod.TrimStart('/');
 
             activity.SetTag(SemanticConventions.AttributeRpcSystem, GrpcTagHelper.RpcSystemGrpc);
-            activity.SetTag(SemanticConventions.AttributeNetPeerIp, context.Connection.RemoteIpAddress.ToString());
+            if (context.Connection.RemoteIpAddress != null)
+            {
+                activity.SetTag(SemanticConventions.AttributeNetPeerIp, context.Connection.RemoteIpAddress.ToString());
+            }
+
             activity.SetTag(SemanticConventions.AttributeNetPeerPort, context.Connection.RemotePort);
 
             bool validConversion = GrpcTagHelper.TryGetGrpcStatusCodeFromActivity(activity, out int status);