From 9b916b2f14f56d6543c5ef50401e4ab7aeb2ad5c Mon Sep 17 00:00:00 2001
From: Martin Kustermann <kustermann@google.com>
Date: Wed, 2 Jul 2025 00:17:33 -0700
Subject: [PATCH] [io] Avoid uncatchable error in RawDatagramSocket.bind()

Currently the error happens very late in C code which throws
a `Dart_NewApiError()` which isn't catchable via try/catch in
Dart.

Our `dart:io` APIs should never result in uncatchable
errors being thrown.

This CL adds the verification that the address is a IPv4/IPv6
address (and not a unix domain socket address) before actually
binding the code.

Issue https://github.com/dart-lang/sdk/issues/60421

TEST=standalone/io/datagram_error_test

Change-Id: I0ead36b8c90dd8b04523f9e64d3be63a8e66a56c
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/438140
Commit-Queue: Martin Kustermann <kustermann@google.com>
Reviewed-by: Slava Egorov <vegorov@google.com>
---
 sdk/lib/_internal/vm/bin/socket_patch.dart   |  7 +++++
 tests/standalone/io/datagram_error.dart      | 30 ------------------
 tests/standalone/io/datagram_error_test.dart | 33 ++++++++------------
 3 files changed, 20 insertions(+), 50 deletions(-)
 delete mode 100644 tests/standalone/io/datagram_error.dart

diff --git a/sdk/lib/_internal/vm/bin/socket_patch.dart b/sdk/lib/_internal/vm/bin/socket_patch.dart
index 46e83151be8..45be821586d 100644
--- a/sdk/lib/_internal/vm/bin/socket_patch.dart
+++ b/sdk/lib/_internal/vm/bin/socket_patch.dart
@@ -1241,6 +1241,13 @@ base class _NativeSocket extends _NativeSocketNativeWrapper
 
     final address = await _resolveHost(host);
 
+    if (address.type != InternetAddressType.IPv6 &&
+        address.type != InternetAddressType.IPv4) {
+      throw SocketException(
+        'Cannot bind datagram socket on non-IPv4/IPv6 address (was: $address)',
+      );
+    }
+
     var socket = _NativeSocket.datagram(address);
     var result = socket._nativeCreateBindDatagram(
       address._in_addr,
diff --git a/tests/standalone/io/datagram_error.dart b/tests/standalone/io/datagram_error.dart
deleted file mode 100644
index fd54aa44513..00000000000
--- a/tests/standalone/io/datagram_error.dart
+++ /dev/null
@@ -1,30 +0,0 @@
-// Copyright (c) 2025, the Dart project authors.  Please see the AUTHORS file
-// for details. All rights reserved. Use of this source code is governed by a
-// BSD-style license that can be found in the LICENSE file.
-//
-// Dart test program for testing error path in datagram bind call.
-
-import 'dart:io';
-
-import "package:expect/expect.dart";
-
-void main() async {
-  try {
-    final socket = await RawDatagramSocket.bind(
-      InternetAddress('/tmp/test_socket', type: InternetAddressType.unix),
-      0,
-    );
-    Expect.fail(
-      "Should not reach this: "
-      "the bind call above should have failed",
-    );
-    socket.listen((data) {
-      print(data);
-    });
-  } catch (e) {
-    Expect.fail(
-      "Should not reach this: "
-      "the bind call above throws unhandled exception",
-    );
-  }
-}
diff --git a/tests/standalone/io/datagram_error_test.dart b/tests/standalone/io/datagram_error_test.dart
index f5fa6b8b5f2..f701e597298 100644
--- a/tests/standalone/io/datagram_error_test.dart
+++ b/tests/standalone/io/datagram_error_test.dart
@@ -1,31 +1,24 @@
 // Copyright (c) 2025, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
-//
-// Dart test program for testing error path in datagram bind call.
-//
-// OtherResources=datagram_error.dart
 
 import 'dart:io';
 
+import "package:async_helper/async_helper.dart";
 import "package:expect/expect.dart";
-import 'package:path/path.dart' as path;
 
 void main() async {
-  var sdkPath = path.absolute(path.dirname(Platform.executable));
-  var dartPath = path.absolute(
-    sdkPath,
-    Platform.isWindows ? 'dart.exe' : 'dart',
-  );
-  // Get the Dart script file that generates output.
-  var scriptFile = new File(
-    Platform.script.resolve("datagram_error.dart").toFilePath(),
-  );
-  var args = <String>[scriptFile.path];
-  ProcessResult syncResult = Process.runSync(dartPath, args);
-  Expect.notEquals(0, syncResult.exitCode);
-  Expect.stringEquals(
-    syncResult.stderr,
-    "Unexpected type for socket address" + Platform.lineTerminator,
+  SocketException? error;
+  try {
+    await RawDatagramSocket.bind(
+      InternetAddress('/tmp/test_socket', type: InternetAddressType.unix),
+      0,
+    );
+  } on SocketException catch (e) {
+    error = e;
+  }
+  Expect.contains(
+    'Cannot bind datagram socket on non-IPv4/IPv6 address',
+    '$error',
   );
 }