Change DefaultMaximumErrorResponseLength to KB from Byte (#105396)

* Change DefaultMaximumErrorResponseLength to KB from Byte

* Handle overflow

* Review feedback

Author: liveans

src/libraries/System.Net.Requests/src/System/Net/HttpWebResponse.cs

@@ -346,7 +346,7 @@ public override Stream GetResponseStream()
                     return contentStream;
                 }
 
-                return new TruncatedReadStream(contentStream, maxErrorResponseLength);
+                return new TruncatedReadStream(contentStream, (long)maxErrorResponseLength * 1024);
             }
 
             return Stream.Null;
@@ -381,8 +381,9 @@ private void CheckDisposed()
 
         private static string GetHeaderValueAsString(IEnumerable<string> values) => string.Join(", ", values);
 
-        internal sealed class TruncatedReadStream(Stream innerStream, int maxSize) : Stream
+        internal sealed class TruncatedReadStream(Stream innerStream, long maxSize) : Stream
         {
+            private long _maxRemainingLength = maxSize;
             public override bool CanRead => true;
             public override bool CanSeek => false;
             public override bool CanWrite => false;
@@ -399,8 +400,8 @@ public override int Read(byte[] buffer, int offset, int count)
 
             public override int Read(Span<byte> buffer)
             {
-                int readBytes = innerStream.Read(buffer.Slice(0, Math.Min(buffer.Length, maxSize)));
-                maxSize -= readBytes;
+                int readBytes = innerStream.Read(buffer.Slice(0, (int)Math.Min(buffer.Length, _maxRemainingLength)));
+                _maxRemainingLength -= readBytes;
                 return readBytes;
             }
 
@@ -411,9 +412,9 @@ public override Task<int> ReadAsync(byte[] buffer, int offset, int count, Cancel
 
             public override async ValueTask<int> ReadAsync(Memory<byte> buffer, CancellationToken cancellationToken = default)
             {
-                int readBytes = await innerStream.ReadAsync(buffer.Slice(0, Math.Min(buffer.Length, maxSize)), cancellationToken)
+                int readBytes = await innerStream.ReadAsync(buffer.Slice(0, (int)Math.Min(buffer.Length, _maxRemainingLength)), cancellationToken)
                     .ConfigureAwait(false);
-                maxSize -= readBytes;
+                _maxRemainingLength -= readBytes;
                 return readBytes;
             }
 

src/libraries/System.Net.Requests/tests/HttpWebRequestTest.cs

@@ -2318,33 +2318,70 @@ await server.AcceptConnectionAsync(
         [ConditionalFact(typeof(RemoteExecutor), nameof(RemoteExecutor.IsSupported))]
         public async Task SendHttpRequest_WhenDefaultMaximumErrorResponseLengthSet_Success()
         {
-            await RemoteExecutor.Invoke(async (async) =>
+            await RemoteExecutor.Invoke(async isAsync =>
             {
                 TaskCompletionSource tcs = new TaskCompletionSource();
                 await LoopbackServer.CreateClientAndServerAsync(
-                async (uri) =>
+                async uri =>
                 {
                     HttpWebRequest request = WebRequest.CreateHttp(uri);
-                    HttpWebRequest.DefaultMaximumErrorResponseLength = 5;
-                    var exception = 
-                        await Assert.ThrowsAsync<WebException>(() => bool.Parse(async) ? request.GetResponseAsync() : Task.Run(() => request.GetResponse()));
+                    HttpWebRequest.DefaultMaximumErrorResponseLength = 1; // 1 KB
+                    WebException exception =
+                        await Assert.ThrowsAsync<WebException>(() => bool.Parse(isAsync) ? request.GetResponseAsync() : Task.Run(() => request.GetResponse()));
                     tcs.SetResult();
                     Assert.NotNull(exception.Response);
-                    using (var responseStream = exception.Response.GetResponseStream())
+                    using (Stream responseStream = exception.Response.GetResponseStream())
                     {
-                        var buffer = new byte[10];
-                        int readLen = responseStream.Read(buffer, 0, buffer.Length);
-                        Assert.Equal(5, readLen);
-                        Assert.Equal(new string('a', 5), Encoding.UTF8.GetString(buffer[0..readLen]));
-                        Assert.Equal(0, responseStream.Read(buffer));
+                        byte[] buffer = new byte[10 * 1024];
+                        int totalReadLen = 0;
+                        int readLen = 0;
+                        while ((readLen = responseStream.Read(buffer, readLen, buffer.Length - readLen)) > 0)
+                        {
+                            totalReadLen += readLen;
+                        }
+
+                        Assert.Equal(1024, totalReadLen);
+                        Assert.Equal(new string('a', 1024), Encoding.UTF8.GetString(buffer[0..totalReadLen]));
                     }
                 },
-                async (server) =>
+                async server =>
+                {
+                    await server.AcceptConnectionAsync(
+                        async connection =>
+                        {
+                            await connection.SendResponseAsync(statusCode: HttpStatusCode.BadRequest, content: new string('a', 10 * 1024));
+                            await tcs.Task;
+                        });
+                });
+            }, IsAsync.ToString()).DisposeAsync();
+        }
+
+        [ConditionalFact(typeof(RemoteExecutor), nameof(RemoteExecutor.IsSupported))]
+        public async Task SendHttpRequest_WhenDefaultMaximumErrorResponseLengthSetToIntMax_DoesNotThrow()
+        {
+            await RemoteExecutor.Invoke(async isAsync =>
+            {
+                TaskCompletionSource tcs = new TaskCompletionSource();
+                await LoopbackServer.CreateClientAndServerAsync(
+                async uri =>
+                {
+                    HttpWebRequest request = WebRequest.CreateHttp(uri);
+                    HttpWebRequest.DefaultMaximumErrorResponseLength = int.MaxValue; // KB
+                    WebException exception =
+                        await Assert.ThrowsAsync<WebException>(() => bool.Parse(isAsync) ? request.GetResponseAsync() : Task.Run(() => request.GetResponse()));
+                    tcs.SetResult();
+                    Assert.NotNull(exception.Response);
+                    using (Stream responseStream = exception.Response.GetResponseStream())
+                    {
+                        Assert.Equal(1, await responseStream.ReadAsync(new byte[1]));
+                    }
+                },
+                async server =>
                 {
                     await server.AcceptConnectionAsync(
                         async connection =>
                         {
-                            await connection.SendResponseAsync(statusCode: HttpStatusCode.BadRequest, content: new string('a', 10));
+                            await connection.SendResponseAsync(statusCode: HttpStatusCode.BadRequest, content: new string('a', 10 * 1024));
                             await tcs.Task;
                         });
                 });