Update Ping.Windows.cs for async task handling

src/libraries/System.Net.Ping/src/System/Net/NetworkInformation/Ping.Windows.cs

@@ -48,6 +48,7 @@
             if (isAsync)
             {
                 _taskCompletionSource = tcs = new TaskCompletionSource<PingReply>();
+
             }
 
             _ipv6 = (address.AddressFamily == AddressFamily.InterNetworkV6);
@@ -303,17 +304,14 @@
             }
         }
 
-        // Copies _requestBuffer into unmanaged memory for async icmpsendecho APIs.
+        // Copies _requestBuffer into unmanaged memory for async icmpsendecho APIs
         private unsafe void SetUnmanagedStructures(byte[] buffer)
         {
+            _requestBuffer?.Dispose();
             _requestBuffer = SafeLocalAllocHandle.LocalAlloc(buffer.Length);
-            byte* dst = (byte*)_requestBuffer.DangerousGetHandle();
-            for (int i = 0; i < buffer.Length; ++i)
-            {
-                dst[i] = buffer[i];
-            }
+            Span<byte> destination = new Span<byte>(_requestBuffer.DangerousGetHandle().ToPointer(), buffer.Length);
+            buffer.CopyTo(destination);
         }
-
         // Releases the unmanaged memory after ping completion.
         private void FreeUnmanagedStructures()
         {
@@ -341,29 +339,24 @@
         {
             const int DontFragmentFlag = 2;
 
-            IPAddress address = new IPAddress(reply.address);
-            IPStatus ipStatus = GetStatusFromCode((int)reply.status);
+             IPAddress address = new IPAddress(reply.address); 
+             IPStatus ipStatus = GetStatusFromCode((int)reply.status);
 
-            long rtt;
-            PingOptions? options;
-            byte[] buffer;
+            var (rtt, options, buffer) = ipStatus == IPStatus.Success
+                ? (reply.roundTripTime, 
+                   new PingOptions(reply.options.ttl, (reply.options.flags & DontFragmentFlag) > 0),
+                   CreateBuffer(reply.data, reply.dataSize))
+                : (0L, null, Array.Empty<byte>());
 
-            if (ipStatus == IPStatus.Success)
-            {
-                // Only copy the data if we succeed w/ the ping operation.
-                rtt = reply.roundTripTime;
-                options = new PingOptions(reply.options.ttl, (reply.options.flags & DontFragmentFlag) > 0);
-                buffer = new byte[reply.dataSize];
-                Marshal.Copy(reply.data, buffer, 0, reply.dataSize);
-            }
-            else
+            return new PingReply(address, options, ipStatus, rtt, buffer);
+
+            static byte[] CreateBuffer(IntPtr data, int dataSize)
             {
-                rtt = 0;
-                options = null;
-                buffer = Array.Empty<byte>();
+                Span<byte> bufferSpan = stackalloc byte[dataSize];
+                Marshal.Copy(data, bufferSpan, 0, dataSize);
+
+                return bufferSpan.ToArray();
             }
-
-            return new PingReply(address, options, ipStatus, rtt, buffer);
         }
 
         private static PingReply CreatePingReplyFromIcmp6EchoReply(in Interop.IpHlpApi.ICMPV6_ECHO_REPLY reply, IntPtr dataPtr, int sendSize)