Fix memory overflow issues

core/dart-bridge/lib.go

@@ -1,6 +1,7 @@
 package dart_bridge
 
 /*
+#include <stdlib.h>
 #include "stdint.h"
 #include "include/dart_api_dl.h"
 #include "include/dart_api_dl.c"
@@ -28,6 +29,7 @@ func SendToPort(port int64, msg string) {
 	var obj C.Dart_CObject
 	obj._type = C.Dart_CObject_kString
 	msgString := C.CString(msg)
+	defer C.free(unsafe.Pointer(msgString))
 	ptr := unsafe.Pointer(&obj.value[0])
 	*(**C.char)(ptr) = msgString
 	isSuccess := C.GoDart_PostCObject(C.Dart_Port_DL(port), &obj)

core/hub.go

@@ -1,5 +1,8 @@
 package main
 
+/*
+#include <stdlib.h>
+*/
 import "C"
 import (
 	bridge "core/dart-bridge"
@@ -71,8 +74,8 @@ func forceGc() {
 //export validateConfig
 func validateConfig(s *C.char, port C.longlong) {
 	i := int64(port)
+	bytes := []byte(C.GoString(s))
 	go func() {
-		bytes := []byte(C.GoString(s))
 		_, err := config.UnmarshalRawConfig(bytes)
 		if err != nil {
 			bridge.SendToPort(i, err.Error())
@@ -85,8 +88,8 @@ func validateConfig(s *C.char, port C.longlong) {
 //export updateConfig
 func updateConfig(s *C.char, port C.longlong) {
 	i := int64(port)
+	paramsString := C.GoString(s)
 	go func() {
-		paramsString := C.GoString(s)
 		var params = &GenerateConfigParams{}
 		err := json.Unmarshal([]byte(paramsString), params)
 		if err != nil {
@@ -148,8 +151,8 @@ func getProxies() *C.char {
 
 //export changeProxy
 func changeProxy(s *C.char) bool {
+	paramsString := C.GoString(s)
 	go func() {
-		paramsString := C.GoString(s)
 		var params = &ChangeProxyParams{}
 		err := json.Unmarshal([]byte(paramsString), params)
 		if err != nil {
@@ -211,8 +214,8 @@ func resetTraffic() {
 //export asyncTestDelay
 func asyncTestDelay(s *C.char, port C.longlong) {
 	i := int64(port)
+	paramsString := C.GoString(s)
 	go func() {
-		paramsString := C.GoString(s)
 		var params = &TestDelayParams{}
 		err := json.Unmarshal([]byte(paramsString), params)
 		if err != nil {
@@ -296,7 +299,6 @@ func closeConnections() bool {
 //export closeConnection
 func closeConnection(id *C.char) bool {
 	connectionId := C.GoString(id)
-
 	err := statistic.DefaultManager.Get(connectionId).Close()
 	if err != nil {
 		return false
@@ -307,10 +309,13 @@ func closeConnection(id *C.char) bool {
 //export getProviders
 func getProviders() *C.char {
 	data, err := json.Marshal(tunnel.Providers())
+	var msg *C.char
 	if err != nil {
-		return C.CString("")
+		msg = C.CString("")
+		return msg
 	}
-	return C.CString(string(data))
+	msg = C.CString(string(data))
+	return msg
 }
 
 //export getProvider
@@ -360,10 +365,9 @@ func getExternalProviders() *C.char {
 //export updateExternalProvider
 func updateExternalProvider(providerName *C.char, providerType *C.char, port C.longlong) {
 	i := int64(port)
+	providerNameString := C.GoString(providerName)
+	providerTypeString := C.GoString(providerType)
 	go func() {
-		providerNameString := C.GoString(providerName)
-		providerTypeString := C.GoString(providerType)
-
 		switch providerTypeString {
 		case "Proxy":
 			providers := tunnel.Providers()
@@ -409,6 +413,11 @@ func initNativeApiBridge(api unsafe.Pointer, port C.longlong) {
 	bridge.Port = &i
 }
 
+//export freeCString
+func freeCString(s *C.char) {
+	C.free(unsafe.Pointer(s))
+}
+
 func init() {
 	provider.HealthcheckHook = func(name string, delay uint16) {
 		delayData := &Delay{

core/process.go

@@ -71,8 +71,8 @@ func setProcessMap(s *C.char) {
 	if s == nil {
 		return
 	}
+	paramsString := C.GoString(s)
 	go func() {
-		paramsString := C.GoString(s)
 		var processMapItem = &ProcessMapItem{}
 		err := json.Unmarshal([]byte(paramsString), processMapItem)
 		if err == nil {

lib/clash/core.dart

@@ -45,10 +45,10 @@ class ClashCore {
   }
 
   bool init(String homeDir) {
-    return clashFFI.initClash(
-      homeDir.toNativeUtf8().cast(),
-    ) ==
-        1;
+    final homeDirChar = homeDir.toNativeUtf8().cast<Char>();
+    final isInit = clashFFI.initClash(homeDirChar) == 1;
+    malloc.free(homeDirChar);
+    return isInit;
   }
 
   shutdown() {
@@ -67,10 +67,12 @@ class ClashCore {
         receiver.close();
       }
     });
+    final dataChar = data.toNativeUtf8().cast<Char>();
     clashFFI.validateConfig(
-      data.toNativeUtf8().cast(),
+      dataChar,
       receiver.sendPort.nativePort,
     );
+    malloc.free(dataChar);
     return completer.future;
   }
 
@@ -84,20 +86,23 @@ class ClashCore {
       }
     });
     final params = json.encode(updateConfigParams);
+    final paramsChar = params.toNativeUtf8().cast<Char>();
     clashFFI.updateConfig(
-      params.toNativeUtf8().cast(),
+      paramsChar,
       receiver.sendPort.nativePort,
     );
+    malloc.free(paramsChar);
     return completer.future;
   }
 
   Future<List<Group>> getProxiesGroups() {
     final proxiesRaw = clashFFI.getProxies();
     final proxiesRawString = proxiesRaw.cast<Utf8>().toDartString();
+    clashFFI.freeCString(proxiesRaw);
     return Isolate.run<List<Group>>(() {
-      if(proxiesRawString.isEmpty) return [];
+      if (proxiesRawString.isEmpty) return [];
       final proxies = (json.decode(proxiesRawString) ?? {}) as Map;
-      if(proxies.isEmpty) return [];
+      if (proxies.isEmpty) return [];
       final groupNames = [
         UsedProxy.GLOBAL.name,
         ...(proxies[UsedProxy.GLOBAL.name]["all"] as List).where((e) {
@@ -111,7 +116,7 @@ class ClashCore {
         group["all"] = ((group["all"] ?? []) as List)
             .map(
               (name) => proxies[name],
-        )
+            )
             .toList();
         return group;
       }).toList();
@@ -122,14 +127,15 @@ class ClashCore {
   Future<List<ExternalProvider>> getExternalProviders() {
     final externalProvidersRaw = clashFFI.getExternalProviders();
     final externalProvidersRawString =
-    externalProvidersRaw.cast<Utf8>().toDartString();
+        externalProvidersRaw.cast<Utf8>().toDartString();
+    clashFFI.freeCString(externalProvidersRaw);
     return Isolate.run<List<ExternalProvider>>(() {
       final externalProviders =
-      (json.decode(externalProvidersRawString) as List<dynamic>)
-          .map(
-            (item) => ExternalProvider.fromJson(item),
-      )
-          .toList();
+          (json.decode(externalProvidersRawString) as List<dynamic>)
+              .map(
+                (item) => ExternalProvider.fromJson(item),
+              )
+              .toList();
       return externalProviders;
     });
   }
@@ -146,17 +152,24 @@ class ClashCore {
         receiver.close();
       }
     });
+    final providerNameChar = providerName.toNativeUtf8().cast<Char>();
+    final providerTypeChar = providerType.toNativeUtf8().cast<Char>();
     clashFFI.updateExternalProvider(
-      providerName.toNativeUtf8().cast(),
-      providerType.toNativeUtf8().cast(),
+      providerNameChar,
+      providerTypeChar,
       receiver.sendPort.nativePort,
     );
+    malloc.free(providerNameChar);
+    malloc.free(providerTypeChar);
     return completer.future;
   }
 
   bool changeProxy(ChangeProxyParams changeProxyParams) {
     final params = json.encode(changeProxyParams);
-    return clashFFI.changeProxy(params.toNativeUtf8().cast()) == 1;
+    final paramsChar = params.toNativeUtf8().cast<Char>();
+    final isInit = clashFFI.changeProxy(paramsChar) == 1;
+    malloc.free(paramsChar);
+    return isInit;
   }
 
   Future<Delay> getDelay(String proxyName) {
@@ -172,13 +185,15 @@ class ClashCore {
         receiver.close();
       }
     });
+    final delayParamsChar = json.encode(delayParams).toNativeUtf8().cast<Char>();
     clashFFI.asyncTestDelay(
-      json.encode(delayParams).toNativeUtf8().cast(),
+      delayParamsChar,
       receiver.sendPort.nativePort,
     );
+    malloc.free(delayParamsChar);
     Future.delayed(httpTimeoutDuration + moreDuration, () {
       receiver.close();
-      if(!completer.isCompleted){
+      if (!completer.isCompleted) {
         completer.complete(
           Delay(name: proxyName, value: -1),
         );
@@ -188,28 +203,33 @@ class ClashCore {
   }
 
   clearEffect(String path) {
-    clashFFI.clearEffect(path.toNativeUtf8().cast());
+    final pathChar = path.toNativeUtf8().cast<Char>();
+    clashFFI.clearEffect(pathChar);
+    malloc.free(pathChar);
   }
 
   VersionInfo getVersionInfo() {
     final versionInfoRaw = clashFFI.getVersionInfo();
     final versionInfo = json.decode(versionInfoRaw.cast<Utf8>().toDartString());
+    clashFFI.freeCString(versionInfoRaw);
     return VersionInfo.fromJson(versionInfo);
   }
 
   Traffic getTraffic() {
     final trafficRaw = clashFFI.getTraffic();
     final trafficMap = json.decode(trafficRaw.cast<Utf8>().toDartString());
+    clashFFI.freeCString(trafficRaw);
     return Traffic.fromMap(trafficMap);
   }
 
   Traffic getTotalTraffic() {
     final trafficRaw = clashFFI.getTotalTraffic();
     final trafficMap = json.decode(trafficRaw.cast<Utf8>().toDartString());
+    clashFFI.freeCString(trafficRaw);
     return Traffic.fromMap(trafficMap);
   }
 
-  void resetTraffic(){
+  void resetTraffic() {
     clashFFI.resetTraffic();
   }
 
@@ -234,7 +254,9 @@ class ClashCore {
   }
 
   void setProcessMap(ProcessMapItem processMapItem) {
-    clashFFI.setProcessMap(json.encode(processMapItem).toNativeUtf8().cast());
+    final processMapItemChar = json.encode(processMapItem).toNativeUtf8().cast<Char>();
+    clashFFI.setProcessMap(processMapItemChar);
+    malloc.free(processMapItemChar);
   }
 
   // DateTime? getRunTime() {
@@ -246,13 +268,16 @@ class ClashCore {
   List<Connection> getConnections() {
     final connectionsDataRaw = clashFFI.getConnections();
     final connectionsData =
-    json.decode(connectionsDataRaw.cast<Utf8>().toDartString()) as Map;
+        json.decode(connectionsDataRaw.cast<Utf8>().toDartString()) as Map;
+    clashFFI.freeCString(connectionsDataRaw);
     final connectionsRaw = connectionsData['connections'] as List? ?? [];
     return connectionsRaw.map((e) => Connection.fromJson(e)).toList();
   }
 
   closeConnections(String id) {
-    clashFFI.closeConnection(id.toNativeUtf8().cast());
+    final idChar = id.toNativeUtf8().cast<Char>();
+    clashFFI.closeConnection(idChar);
+    malloc.free(idChar);
   }
 }
 

pubspec.yaml

@@ -1,7 +1,7 @@
 name: fl_clash
 description: A multi-platform proxy client based on ClashMeta, simple and easy to use, open-source and ad-free.
 publish_to: 'none'
-version: 0.8.30
+version: 0.8.31
 environment:
   sdk: '>=3.1.0 <4.0.0'