Fix broken package reader

Frameworks/MQTTnet.NetStandard/Adapter/MqttChannelAdapter.cs

@@ -137,7 +137,7 @@ namespace MQTTnet.Adapter
                 return new ReceivedMqttPacket(header, new MemoryStream(new byte[0], false));
             }
 
-            var body = header.BodyLength <= ReadBufferSize ? new MemoryStream(new byte[header.BodyLength]) : new MemoryStream();
+            var body = header.BodyLength <= ReadBufferSize ? new MemoryStream(header.BodyLength) : new MemoryStream();
             
             var buffer = new byte[ReadBufferSize];
             while (body.Length < header.BodyLength)

Tests/MQTTnet.Core.Tests/MqttClientTests.cs

@@ -1,5 +1,4 @@
-using System;
-using System.Net.Sockets;
+using System.Net.Sockets;
 using System.Threading.Tasks;
 using Microsoft.VisualStudio.TestTools.UnitTesting;
 using MQTTnet.Client;

Tests/MQTTnet.Core.Tests/MqttServerTests.cs

@@ -299,7 +299,7 @@ namespace MQTTnet.Core.Tests
 
             var serverAdapter = new TestMqttServerAdapter();
             var s = new MqttFactory().CreateMqttServer(new[] { serverAdapter }, new MqttNetLogger());
-            
+
             try
             {
                 var options = new MqttServerOptions { ApplicationMessageInterceptor = Interceptor };
@@ -330,6 +330,41 @@ namespace MQTTnet.Core.Tests
             }
         }
 
+        [TestMethod]
+        public async Task MqttServer_Body()
+        {
+            var serverAdapter = new TestMqttServerAdapter();
+            var s = new MqttFactory().CreateMqttServer(new[] { serverAdapter }, new MqttNetLogger());
+
+            var bodyIsMatching = false;
+            try
+            {
+                await s.StartAsync(new MqttServerOptions());
+
+                var c1 = await serverAdapter.ConnectTestClient(s, "c1");
+                var c2 = await serverAdapter.ConnectTestClient(s, "c2");
+                
+                c1.ApplicationMessageReceived += (_, e) =>
+                {
+                    if (Encoding.UTF8.GetString(e.ApplicationMessage.Payload) == "The body")
+                    {
+                        bodyIsMatching = true;
+                    }
+                };
+
+                await c1.SubscribeAsync("A", MqttQualityOfServiceLevel.AtMostOnce);
+                await c2.PublishAsync(new MqttApplicationMessageBuilder().WithTopic("A").WithPayload(Encoding.UTF8.GetBytes("The body")).Build());
+
+                await Task.Delay(500);
+            }
+            finally
+            {
+                await s.StopAsync();
+            }
+
+            Assert.IsTrue(bodyIsMatching);
+        }
+
         private class TestStorage : IMqttServerStorage
         {
             private IList<MqttApplicationMessage> _messages = new List<MqttApplicationMessage>();