diff --git a/common/include/dscreen_errcode.h b/common/include/dscreen_errcode.h
index 0806f91e2d4b1fdd6c5389ca1be6e24e69c860f4..ae4b32b355c593a74136f2fe4cc6d5d2b3f22428 100644
--- a/common/include/dscreen_errcode.h
+++ b/common/include/dscreen_errcode.h
@@ -97,8 +97,9 @@ enum DScreenErrorCode {
     ERR_DH_SCREEN_SCREENCLIENT_HIDE_WINDOW_ERROR = -54004,
     // screen register callback
     ERR_DH_SCREEN_REGISTER_CALLBACK_NOT_INIT = -55000,
-    // screen string param empty
+    // screen string param empty or screen input param invalid
     ERR_DH_SCREEN_STRING_PARAM_EMPTY = -56000,
+    ERR_DH_SCREEN_INPUT_PARAM_INVALID = -56001,
 };
 } // namespace DistributedHardware
 } // namespace OHOS
diff --git a/interfaces/innerkits/native_cpp/screen_sink/include/dscreen_sink_proxy.h b/interfaces/innerkits/native_cpp/screen_sink/include/dscreen_sink_proxy.h
index 34e9d14b7cdd8912eb282f636246919900a25d02..853f7a50c7ccbce6516b9ecdca9c65952bd81b4c 100644
--- a/interfaces/innerkits/native_cpp/screen_sink/include/dscreen_sink_proxy.h
+++ b/interfaces/innerkits/native_cpp/screen_sink/include/dscreen_sink_proxy.h
@@ -43,6 +43,9 @@ public:
 
 private:
     static inline BrokerDelegator<DScreenSinkProxy> delegator_;
+
+    const size_t DID_MAX_SIZE = 256;
+    const size_t PARAM_MAX_SIZE = 50 * 1024 * 1024;
 };
 } // namespace DistributedHardware
 } // namespace OHOS
diff --git a/interfaces/innerkits/native_cpp/screen_sink/src/dscreen_sink_proxy.cpp b/interfaces/innerkits/native_cpp/screen_sink/src/dscreen_sink_proxy.cpp
index 1da1aeba8997fd2abd5ce34980746f0318ba0067..691982361de31c7af8e0459776eeb17d03c5faec 100644
--- a/interfaces/innerkits/native_cpp/screen_sink/src/dscreen_sink_proxy.cpp
+++ b/interfaces/innerkits/native_cpp/screen_sink/src/dscreen_sink_proxy.cpp
@@ -27,6 +27,10 @@ namespace OHOS {
 namespace DistributedHardware {
 int32_t DScreenSinkProxy::InitSink(const std::string &params)
 {
+    if (params.empty() || params.size() > PARAM_MAX_SIZE) {
+        DHLOGE("InitSink error: invalid parameter.");
+        return ERR_DH_SCREEN_INPUT_PARAM_INVALID;
+    }
     sptr<IRemoteObject> remote = Remote();
     if (remote == nullptr) {
         DHLOGE("DScreenSinkProxy remote service null");
@@ -72,6 +76,10 @@ int32_t DScreenSinkProxy::ReleaseSink()
 
 int32_t DScreenSinkProxy::SubscribeLocalHardware(const std::string &dhId, const std::string &param)
 {
+    if (dhId.empty() || dhId.size() > DID_MAX_SIZE || param.empty() || param.size() > PARAM_MAX_SIZE) {
+        DHLOGE("SubscribeLocalHardware error: invalid parameter.");
+        return ERR_DH_SCREEN_INPUT_PARAM_INVALID;
+    }
     sptr<IRemoteObject> remote = Remote();
     if (remote == nullptr) {
         DHLOGE("DScreenSinkProxy remote service null");
@@ -97,6 +105,10 @@ int32_t DScreenSinkProxy::SubscribeLocalHardware(const std::string &dhId, const
 
 int32_t DScreenSinkProxy::UnsubscribeLocalHardware(const std::string &dhId)
 {
+    if (dhId.empty() || dhId.size() > DID_MAX_SIZE) {
+        DHLOGE("UnsubscribeLocalHardware error: invalid parameter.");
+        return ERR_DH_SCREEN_INPUT_PARAM_INVALID;
+    }
     sptr<IRemoteObject> remote = Remote();
     if (remote == nullptr) {
         DHLOGE("DScreenSinkProxy remote service null");
@@ -122,6 +134,11 @@ int32_t DScreenSinkProxy::UnsubscribeLocalHardware(const std::string &dhId)
 
 void DScreenSinkProxy::DScreenNotify(const std::string &devId, int32_t eventCode, const std::string &eventContent)
 {
+    if (devId.empty() || devId.size() > DID_MAX_SIZE || eventContent.empty() ||
+        eventContent.size() > PARAM_MAX_SIZE) {
+            DHLOGE("DScreenNotify error: invalid parameter.");
+            return;
+    }
     sptr<IRemoteObject> remote = Remote();
     if (remote == nullptr) {
         DHLOGE("DScreenSinkProxy remote service null");
diff --git a/interfaces/innerkits/native_cpp/screen_source/include/callback/dscreen_source_callback_stub.h b/interfaces/innerkits/native_cpp/screen_source/include/callback/dscreen_source_callback_stub.h
index 65a48aae1096131dc5331cafe866ea4fb8d46b36..ca7ae8aa1bdf66c63fe0afe0b7a00de699bacb08 100644
--- a/interfaces/innerkits/native_cpp/screen_source/include/callback/dscreen_source_callback_stub.h
+++ b/interfaces/innerkits/native_cpp/screen_source/include/callback/dscreen_source_callback_stub.h
@@ -38,11 +38,15 @@ private:
     using DScreenFunc = int32_t (DScreenSourceCallbackStub::*)(MessageParcel &data, MessageParcel &reply,
         MessageOption &option);
     std::map<int32_t, DScreenFunc> memberFuncMap_;
+    const size_t DID_MAX_SIZE = 256;
+    const size_t PARAM_MAX_SIZE = 50 * 1024 * 1024;
 
     int32_t OnNotifyRegResultInner(MessageParcel &data, MessageParcel &reply,
         MessageOption &option);
     int32_t OnNotifyUnregResultInner(MessageParcel &data, MessageParcel &reply,
         MessageOption &option);
+    bool CheckParams(const std::string &devId, const std::string &dhId, const std::string &reqId,
+        const std::string &resultData);
 };
 }
 }
diff --git a/interfaces/innerkits/native_cpp/screen_source/include/dscreen_source_proxy.h b/interfaces/innerkits/native_cpp/screen_source/include/dscreen_source_proxy.h
index 13c3df828652b262a32c180b57df7ff652f77f1d..7fe69409775087205596435e4145f99e13b5f94f 100644
--- a/interfaces/innerkits/native_cpp/screen_source/include/dscreen_source_proxy.h
+++ b/interfaces/innerkits/native_cpp/screen_source/include/dscreen_source_proxy.h
@@ -47,6 +47,13 @@ public:
 
 private:
     static inline BrokerDelegator<DScreenSourceProxy> delegator_;
+    bool CheckRegParams(const std::string &devId, const std::string &dhId,
+        const EnableParam &param, const std::string &reqId);
+    bool CheckUnregParams(const std::string &devId, const std::string &dhId, const std::string &reqId);
+    bool CheckConfigParams(const std::string &devId, const std::string &dhId,
+        const std::string &key, const std::string &value);
+    const size_t DID_MAX_SIZE = 256;
+    const size_t PARAM_MAX_SIZE = 50 * 1024 * 1024;
 };
 }
 }
diff --git a/interfaces/innerkits/native_cpp/screen_source/src/callback/dscreen_source_callback_stub.cpp b/interfaces/innerkits/native_cpp/screen_source/src/callback/dscreen_source_callback_stub.cpp
index faaf680268235531f31368db37f7b3b7e8a5d5ed..79744f0de9fdb7b73b18221e59cd476f953db852 100644
--- a/interfaces/innerkits/native_cpp/screen_source/src/callback/dscreen_source_callback_stub.cpp
+++ b/interfaces/innerkits/native_cpp/screen_source/src/callback/dscreen_source_callback_stub.cpp
@@ -60,6 +60,10 @@ int32_t DScreenSourceCallbackStub::OnNotifyRegResultInner(MessageParcel &data, M
     std::string reqId = data.ReadString();
     int32_t status = data.ReadInt32();
     std::string resultData = data.ReadString();
+    if (!CheckParams(devId, dhId, reqId, resultData)) {
+        DHLOGE("OnNotifyRegResultInner error: Invalid parameter.");
+        return ERR_DH_SCREEN_INPUT_PARAM_INVALID;
+    }
     int32_t ret = OnNotifyRegResult(devId, dhId, reqId, status, resultData);
     return ret;
 }
@@ -72,8 +76,26 @@ int32_t DScreenSourceCallbackStub::OnNotifyUnregResultInner(MessageParcel &data,
     std::string reqId = data.ReadString();
     int32_t status = data.ReadInt32();
     std::string resultData = data.ReadString();
+    if (!CheckParams(devId, dhId, reqId, resultData)) {
+        DHLOGE("OnNotifyUnregResultInner error: Invalid parameter.");
+        return ERR_DH_SCREEN_INPUT_PARAM_INVALID;
+    }
     int32_t ret = OnNotifyUnregResult(devId, dhId, reqId, status, resultData);
     return ret;
 }
+
+bool DScreenSourceCallbackStub::CheckParams(const std::string &devId, const std::string &dhId,
+    const std::string &reqId, const std::string &resultData)
+{
+    if (devId.empty() || devId.size() > DID_MAX_SIZE || dhId.empty() || dhId.size() > DID_MAX_SIZE) {
+        DHLOGE("DScreenSourceCallbackStub CheckParams devId or dhId is invalid.");
+        return false;
+    }
+    if (reqId.empty() || reqId.size() > DID_MAX_SIZE || resultData.empty() || resultData.size() > PARAM_MAX_SIZE) {
+        DHLOGE("DScreenSourceCallbackStub CheckParams reqId or resultData is invalid.");
+        return false;
+    }
+    return true;
+}
 }
 }
\ No newline at end of file
diff --git a/interfaces/innerkits/native_cpp/screen_source/src/dscreen_source_proxy.cpp b/interfaces/innerkits/native_cpp/screen_source/src/dscreen_source_proxy.cpp
index 37fc7138256331fbbf25caf752e78801c38715ce..7daa876cca155c6b39adcc2649cfd2faf1bfd6fa 100644
--- a/interfaces/innerkits/native_cpp/screen_source/src/dscreen_source_proxy.cpp
+++ b/interfaces/innerkits/native_cpp/screen_source/src/dscreen_source_proxy.cpp
@@ -28,11 +28,16 @@ namespace OHOS {
 namespace DistributedHardware {
 int32_t DScreenSourceProxy::InitSource(const std::string &params, const sptr<IDScreenSourceCallback> &callback)
 {
+    if (params.empty() || params.size() > PARAM_MAX_SIZE || callback == nullptr) {
+        DHLOGE("InitSource error: invalid parameter");
+        return ERR_DH_SCREEN_INPUT_PARAM_INVALID;
+    }
     sptr<IRemoteObject> remote = Remote();
     if (remote == nullptr) {
         DHLOGE("DScreenSourceProxy remote service null");
         return DSCREEN_BAD_VALUE;
     }
+
     MessageParcel data;
     MessageParcel reply;
     MessageOption option;
@@ -59,6 +64,7 @@ int32_t DScreenSourceProxy::ReleaseSource()
         DHLOGE("DScreenSourceProxy remote service null");
         return DSCREEN_BAD_VALUE;
     }
+
     MessageParcel data;
     MessageParcel reply;
     MessageOption option;
@@ -75,11 +81,16 @@ int32_t DScreenSourceProxy::ReleaseSource()
 int32_t DScreenSourceProxy::RegisterDistributedHardware(const std::string &devId,
     const std::string &dhId, const EnableParam &param, const std::string &reqId)
 {
+    if (!CheckRegParams(devId, dhId, param, reqId)) {
+        DHLOGE("RegisterDistributedHardware error: invalid parameter");
+        return ERR_DH_SCREEN_INPUT_PARAM_INVALID;
+    }
     sptr<IRemoteObject> remote = Remote();
     if (remote == nullptr) {
         DHLOGE("DScreenSourceProxy remote service null");
         return DSCREEN_BAD_VALUE;
     }
+
     MessageParcel data;
     MessageParcel reply;
     MessageOption option;
@@ -102,11 +113,16 @@ int32_t DScreenSourceProxy::RegisterDistributedHardware(const std::string &devId
 int32_t DScreenSourceProxy::UnregisterDistributedHardware(const std::string &devId,
     const std::string &dhId, const std::string &reqId)
 {
+    if (!CheckUnregParams(devId, dhId, reqId)) {
+        DHLOGE("UnregisterDistributedHardware error: invalid parameter");
+        return ERR_DH_SCREEN_INPUT_PARAM_INVALID;
+    }
     sptr<IRemoteObject> remote = Remote();
     if (remote == nullptr) {
         DHLOGE("DScreenSourceProxy remote service null");
         return DSCREEN_BAD_VALUE;
     }
+
     MessageParcel data;
     MessageParcel reply;
     MessageOption option;
@@ -128,11 +144,16 @@ int32_t DScreenSourceProxy::UnregisterDistributedHardware(const std::string &dev
 int32_t DScreenSourceProxy::ConfigDistributedHardware(const std::string &devId,
     const std::string &dhId, const std::string &key, const std::string &value)
 {
+    if (!CheckConfigParams(devId, dhId, key, value)) {
+        DHLOGE("ConfigDistributedHardware error: invalid parameter");
+        return ERR_DH_SCREEN_INPUT_PARAM_INVALID;
+    }
     sptr<IRemoteObject> remote = Remote();
     if (remote == nullptr) {
         DHLOGE("DScreenSourceProxy remote service null");
         return DSCREEN_BAD_VALUE;
     }
+
     MessageParcel data;
     MessageParcel reply;
     MessageOption option;
@@ -151,14 +172,19 @@ int32_t DScreenSourceProxy::ConfigDistributedHardware(const std::string &devId,
     return ret;
 }
 
-void DScreenSourceProxy::DScreenNotify(const std::string &devId,
-    int32_t eventCode, const std::string &eventContent)
+void DScreenSourceProxy::DScreenNotify(const std::string &devId, int32_t eventCode, const std::string &eventContent)
 {
+    if (devId.empty() || devId.size() > DID_MAX_SIZE || eventContent.empty() ||
+        eventContent.size() > PARAM_MAX_SIZE) {
+        DHLOGE("DScreenNotify error: invalid parameter");
+        return;
+    }
     sptr<IRemoteObject> remote = Remote();
     if (remote == nullptr) {
         DHLOGE("DScreenSourceProxy remote service null");
         return;
     }
+
     MessageParcel data;
     MessageParcel reply;
     MessageOption option = { MessageOption::TF_ASYNC };
@@ -174,5 +200,51 @@ void DScreenSourceProxy::DScreenNotify(const std::string &devId,
 
     remote->SendRequest(DSCREEN_NOTIFY, data, reply, option);
 }
+
+bool DScreenSourceProxy::CheckRegParams(const std::string &devId, const std::string &dhId,
+    const EnableParam &param, const std::string &reqId)
+{
+    if (devId.empty() || devId.size() > DID_MAX_SIZE || dhId.empty() || dhId.size() > DID_MAX_SIZE) {
+        DHLOGE("DScreenSourceProxy CheckRegParams devId or dhId is invalid.");
+        return false;
+    }
+    if (reqId.empty() || reqId.size() > DID_MAX_SIZE) {
+        DHLOGE("DScreenSourceProxy CheckRegParams reqId is invalid.");
+        return false;
+    }
+    if (param.version.empty() || param.version.size() > PARAM_MAX_SIZE || param.attrs.empty() ||
+        param.attrs.size() > PARAM_MAX_SIZE) {
+        DHLOGE("DScreenSourceProxy CheckRegParams param is invalid.");
+        return false;
+    }
+    return true;
+}
+
+bool DScreenSourceProxy::CheckUnregParams(const std::string &devId, const std::string &dhId, const std::string &reqId)
+{
+    if (devId.empty() || devId.size() > DID_MAX_SIZE || dhId.empty() || dhId.size() > DID_MAX_SIZE) {
+        DHLOGE("DScreenSourceProxy CheckUnregParams devId or dhId is invalid.");
+        return false;
+    }
+    if (reqId.empty() || reqId.size() > DID_MAX_SIZE) {
+        DHLOGE("DScreenSourceProxy CheckUnregParams reqId is invalid.");
+        return false;
+    }
+    return true;
+}
+
+bool DScreenSourceProxy::CheckConfigParams(const std::string &devId, const std::string &dhId,
+    const std::string &key, const std::string &value)
+{
+    if (devId.empty() || devId.size() > DID_MAX_SIZE || dhId.empty() || dhId.size() > DID_MAX_SIZE) {
+        DHLOGE("DScreenSourceProxy CheckConfigParams devId or dhId is invalid.");
+        return false;
+    }
+    if (key.empty() || key.size() > PARAM_MAX_SIZE || value.empty() || value.size() > PARAM_MAX_SIZE) {
+        DHLOGE("DScreenSourceProxy CheckConfigParams key or value is invalid.");
+        return false;
+    }
+    return true;
+}
 }
 }
diff --git a/services/screenclient/src/screen_client.cpp b/services/screenclient/src/screen_client.cpp
index a2b17115838b04f7a4a2c4ac913c1ef491bf35a8..5a61184e9f9f392964f449637114d34973b2e4db 100644
--- a/services/screenclient/src/screen_client.cpp
+++ b/services/screenclient/src/screen_client.cpp
@@ -75,7 +75,7 @@ int32_t ScreenClient::ShowWindow(int32_t windowId)
     int32_t ret = ScreenClientWindowAdapter::GetInstance().ShowWindow(windowId);
     if (DH_SUCCESS != ret) {
         DHLOGE("Show window (ID = %d) failed.", windowId);
-        return ERR_DH_SCREEN_SCREENCLIENT_SHOW_WINDOW_ERROR;
+        return ret;
     }
     DHLOGI("Show window (ID = %d) success.", windowId);
     return ret;
@@ -94,7 +94,7 @@ int32_t ScreenClient::HideWindow(int32_t windowId)
     int32_t ret = ScreenClientWindowAdapter::GetInstance().HideWindow(windowId);
     if (DH_SUCCESS != ret) {
         DHLOGE("Hide window (ID = %d) failed.", windowId);
-        return ERR_DH_SCREEN_SCREENCLIENT_HIDE_WINDOW_ERROR;
+        return ret;
     }
     DHLOGI("Hide window (ID = %d) success.", windowId);
     return ret;
@@ -113,7 +113,7 @@ int32_t ScreenClient::MoveWindow(int32_t windowId, int32_t startX, int32_t start
     int32_t ret = ScreenClientWindowAdapter::GetInstance().MoveWindow(windowId, startX, startY);
     if (DH_SUCCESS != ret) {
         DHLOGE("Move window (ID = %d) failed.", windowId);
-        return ERR_DH_SCREEN_SCREENCLIENT_MOVE_WINDOW_ERROR;
+        return ret;
     }
     DHLOGD("Move window (ID = %d) success.", windowId);
     return ret;
@@ -153,7 +153,7 @@ int32_t ScreenClient::RemoveWindow(int32_t windowId)
     int32_t ret = ScreenClientWindowAdapter::GetInstance().RemoveWindow(windowId);
     if (ret != DH_SUCCESS) {
         DHLOGE("windowId (ID = %d) remove failed.", windowId);
-        return ERR_DH_SCREEN_SCREENCLIENT_REMOVE_WINDOW_ERROR;
+        return ret;
     }
     DHLOGD("windowId (ID = %d) remove success.", windowId);
     return DH_SUCCESS;
diff --git a/services/screenservice/sinkservice/dscreenservice/include/dscreen_sink_stub.h b/services/screenservice/sinkservice/dscreenservice/include/dscreen_sink_stub.h
index 7f13411fbfe8335c07e71e09ba018ae4abee472e..ce4b223a6fa233f506befe14baa9b99d991e439a 100644
--- a/services/screenservice/sinkservice/dscreenservice/include/dscreen_sink_stub.h
+++ b/services/screenservice/sinkservice/dscreenservice/include/dscreen_sink_stub.h
@@ -45,6 +45,9 @@ private:
         MessageOption &option);
     int32_t DScreenNotifyInner(MessageParcel &data, MessageParcel &reply,
         MessageOption &option);
+
+    const size_t DID_MAX_SIZE = 256;
+    const size_t PARAM_MAX_SIZE = 50 * 1024 * 1024;
 };
 } // namespace DistributedHardware
 } // namespace OHOS
diff --git a/services/screenservice/sinkservice/dscreenservice/src/dscreen_sink_stub.cpp b/services/screenservice/sinkservice/dscreenservice/src/dscreen_sink_stub.cpp
index e735fac05f0f561c486a93ee3599b9d9f84e2f72..6c4eaf6c7ae272464aa32ed5661f2c791855d633 100644
--- a/services/screenservice/sinkservice/dscreenservice/src/dscreen_sink_stub.cpp
+++ b/services/screenservice/sinkservice/dscreenservice/src/dscreen_sink_stub.cpp
@@ -53,6 +53,10 @@ int32_t DScreenSinkStub::InitSinkInner(MessageParcel &data, MessageParcel &reply
     MessageOption &option)
 {
     std::string param = data.ReadString();
+    if (param.empty() || param.size() > PARAM_MAX_SIZE) {
+        DHLOGE("InitSinkInner error: invalid parameter.");
+        return ERR_DH_SCREEN_INPUT_PARAM_INVALID;
+    }
     int32_t ret = InitSink(param);
     reply.WriteInt32(ret);
     return DH_SUCCESS;
@@ -71,6 +75,10 @@ int32_t DScreenSinkStub::SubscribeDistributedHardwareInner(MessageParcel &data,
 {
     std::string dhId = data.ReadString();
     std::string param = data.ReadString();
+    if (dhId.empty() || dhId.size() > DID_MAX_SIZE || param.empty() || param.size() > PARAM_MAX_SIZE) {
+        DHLOGE("SubscribeDistributedHardwareInner error: invalid parameter.");
+        return ERR_DH_SCREEN_INPUT_PARAM_INVALID;
+    }
     int32_t ret = SubscribeLocalHardware(dhId, param);
     reply.WriteInt32(ret);
     return DH_SUCCESS;
@@ -80,6 +88,10 @@ int32_t DScreenSinkStub::UnsubscribeDistributedHardwareInner(MessageParcel &data
     MessageOption &option)
 {
     std::string dhId = data.ReadString();
+    if (dhId.empty() || dhId.size() > DID_MAX_SIZE) {
+        DHLOGE("UnsubscribeDistributedHardwareInner error: invalid parameter.");
+        return ERR_DH_SCREEN_INPUT_PARAM_INVALID;
+    }
     int32_t ret = UnsubscribeLocalHardware(dhId);
     reply.WriteInt32(ret);
     return DH_SUCCESS;
@@ -91,7 +103,11 @@ int32_t DScreenSinkStub::DScreenNotifyInner(MessageParcel &data, MessageParcel &
     std::string devId = data.ReadString();
     int32_t eventCode = data.ReadInt32();
     std::string eventContent = data.ReadString();
-
+    if (devId.empty() || devId.size() > DID_MAX_SIZE || eventContent.empty() ||
+        eventContent.size() > PARAM_MAX_SIZE) {
+        DHLOGE("DScreenNotifyInner error: invalid parameter.");
+        return ERR_DH_SCREEN_INPUT_PARAM_INVALID;
+    }
     DScreenNotify(devId, eventCode, eventContent);
     return DH_SUCCESS;
 }
diff --git a/services/screenservice/sourceservice/dscreenmgr/include/screen_manager_adapter.h b/services/screenservice/sourceservice/dscreenmgr/include/screen_manager_adapter.h
index da25606f864bcb7604e40a64f492301f2cb55b07..c795dcf64b95a0c495639d8aa231c23c6ef18b64 100644
--- a/services/screenservice/sourceservice/dscreenmgr/include/screen_manager_adapter.h
+++ b/services/screenservice/sourceservice/dscreenmgr/include/screen_manager_adapter.h
@@ -44,7 +44,7 @@ private:
     ScreenMgrAdapter() = default;
     ~ScreenMgrAdapter();
 
-    bool listenerRegistered = false;
+    bool listenerRegistered_ = false;
     std::map<std::string, uint64_t> screenIdMap_;
 };
 } // namespace DistributedHardware
diff --git a/services/screenservice/sourceservice/dscreenmgr/src/dscreen.cpp b/services/screenservice/sourceservice/dscreenmgr/src/dscreen.cpp
index fc4409b212f617c6d5f134c7ed10c1b0c05bcd6d..ce7e18168feb78ee18563d4b6ed585425e05c1e2 100644
--- a/services/screenservice/sourceservice/dscreenmgr/src/dscreen.cpp
+++ b/services/screenservice/sourceservice/dscreenmgr/src/dscreen.cpp
@@ -184,7 +184,7 @@ void DScreen::HandleEnable(const std::string &param, const std::string &taskId)
 {
     DHLOGI("HandleEnable, devId: %s, dhId: %s", GetAnonyString(devId_).c_str(), GetAnonyString(dhId_).c_str());
     if (curState_ == ENABLED || curState_ == ENABLING || curState_ == CONNECTING || curState_ == CONNECTED) {
-        dscreenCallback_->OnRegResult(shared_from_this(), taskId, DH_SUCCESS, "");
+        dscreenCallback_->OnRegResult(shared_from_this(), taskId, DH_SUCCESS, "dscreen enable success.");
         return;
     }
 
@@ -229,7 +229,7 @@ void DScreen::HandleEnable(const std::string &param, const std::string &taskId)
     }
     screenId_ = screenId;
     SetState(ENABLED);
-    dscreenCallback_->OnRegResult(shared_from_this(), taskId, DH_SUCCESS, "");
+    dscreenCallback_->OnRegResult(shared_from_this(), taskId, DH_SUCCESS, "dscreen enable success.");
     ReportRegisterScreenEvent(DSCREEN_REGISTER, GetAnonyString(devId_).c_str(), GetAnonyString(dhId_).c_str(),
         "dscreen enable success.");
 }
@@ -267,9 +267,12 @@ int32_t DScreen::NegotiateCodecType(const std::string &remoteCodecInfoStr)
     std::vector<std::shared_ptr<Media::VideoCaps>> caps = codecList->GetVideoEncoderCaps();
     for (const auto &cap : caps) {
         std::shared_ptr<Media::AVCodecInfo> codecInfo = cap->GetCodecInfo();
+        if (codecInfo == nullptr) {
+            continue;
+        }
         localCodecArray.push_back(codecInfo->GetName());
     }
-    
+
     std::vector<std::string> codecTypeCandidates;
     for (const auto &remoteCodecType : remoteCodecArray) {
         if (std::find(localCodecArray.begin(), localCodecArray.end(),
@@ -277,7 +280,7 @@ int32_t DScreen::NegotiateCodecType(const std::string &remoteCodecInfoStr)
             codecTypeCandidates.push_back(remoteCodecType);
         }
     }
-    
+
     if (std::find(codecTypeCandidates.begin(), codecTypeCandidates.end(),
         CODEC_NAME_H264) != codecTypeCandidates.end()) {
         videoParam_->SetCodecType(VIDEO_CODEC_TYPE_VIDEO_H264);
diff --git a/services/screenservice/sourceservice/dscreenmgr/src/dscreen_manager.cpp b/services/screenservice/sourceservice/dscreenmgr/src/dscreen_manager.cpp
index c3e4d3db93988fb565e997d51cb7dabd41b6fd44..35f2673e1a5a4bd48d228c0e30ab9f3120d647ed 100644
--- a/services/screenservice/sourceservice/dscreenmgr/src/dscreen_manager.cpp
+++ b/services/screenservice/sourceservice/dscreenmgr/src/dscreen_manager.cpp
@@ -319,7 +319,7 @@ std::shared_ptr<DScreen> DScreenManager::FindDScreenByScreenId(uint64_t screenId
     std::lock_guard<std::mutex> lock(dScreenMapMtx_);
     for (const auto &iter : dScreens_) {
         std::shared_ptr<DScreen> dScreen = iter.second;
-        if (!dScreen) {
+        if (dScreen == nullptr) {
             continue;
         }
 
@@ -346,7 +346,7 @@ void DScreenManager::GetScreenDumpInfo(std::string &result)
     for (const auto &iter : dScreens_) {
         result.append("    {\n");
         std::shared_ptr<DScreen> dScreen = iter.second;
-        if (!dScreen) {
+        if (dScreen == nullptr) {
             continue;
         }
         uint64_t screenId = dScreen->GetScreenId();
@@ -389,7 +389,7 @@ int32_t DScreenManager::NotifyRemoteScreenService(const std::string &devId, int3
     DHLOGI("Notify remote sink screen service, remote devId: %s, eventCode: %d",
         GetAnonyString(devId).c_str(), eventCode);
     sptr<IDScreenSink> remoteSinkSA = GetDScreenSinkSA(devId);
-    if (!remoteSinkSA) {
+    if (remoteSinkSA == nullptr) {
         DHLOGE("get remote sink sa failed.");
         return ERR_DH_SCREEN_SA_GET_REMOTE_SINK_SERVICE_FAIL;
     }
@@ -409,7 +409,7 @@ sptr<IDScreenSink> DScreenManager::GetDScreenSinkSA(const std::string &devId)
     DHLOGI("GetDScreenSinkSA, devId: %s", GetAnonyString(devId).c_str());
     sptr<ISystemAbilityManager> samgr =
         SystemAbilityManagerClient::GetInstance().GetSystemAbilityManager();
-    if (!samgr) {
+    if (samgr == nullptr) {
         DHLOGE("Failed to get system ability mgr.");
         return nullptr;
     }
diff --git a/services/screenservice/sourceservice/dscreenmgr/src/screen_manager_adapter.cpp b/services/screenservice/sourceservice/dscreenmgr/src/screen_manager_adapter.cpp
index 7141040bd5a049bd8468369f69fd2c092318af9e..309af680c2477c6451cb4baa643ae0be482e0a8e 100644
--- a/services/screenservice/sourceservice/dscreenmgr/src/screen_manager_adapter.cpp
+++ b/services/screenservice/sourceservice/dscreenmgr/src/screen_manager_adapter.cpp
@@ -73,7 +73,7 @@ uint64_t ScreenMgrAdapter::CreateVirtualScreen(const std::string &devId, const s
 int32_t ScreenMgrAdapter::RegisterScreenGroupListener(sptr<Rosen::ScreenManager::IScreenGroupListener> listener)
 {
     DHLOGI("RegisterScreenGroupListener");
-    if (listenerRegistered) {
+    if (listenerRegistered_) {
         DHLOGI("already registered listener.");
         return DH_SUCCESS;
     }
@@ -82,14 +82,14 @@ int32_t ScreenMgrAdapter::RegisterScreenGroupListener(sptr<Rosen::ScreenManager:
         DHLOGE("RegisterScreenGroupListener Failed.");
         return ERR_DH_SCREEN_SA_REGISTER_SCREENLISTENER_FAIL;
     }
-    listenerRegistered = true;
+    listenerRegistered_ = true;
     return DH_SUCCESS;
 }
 
 int32_t ScreenMgrAdapter::UnregisterScreenGroupListener(sptr<Rosen::ScreenManager::IScreenGroupListener> listener)
 {
     DHLOGI("UnregisterScreenGroupListener");
-    if (!listenerRegistered) {
+    if (!listenerRegistered_) {
         DHLOGI("listener already unregistered.");
         return DH_SUCCESS;
     }
@@ -98,7 +98,7 @@ int32_t ScreenMgrAdapter::UnregisterScreenGroupListener(sptr<Rosen::ScreenManage
         DHLOGE("UnregisterScreenGroupListener Failed.");
         return ERR_DH_SCREEN_SA_UNREGISTER_SCREENLISTENER_FAIL;
     }
-    listenerRegistered = false;
+    listenerRegistered_ = false;
     return DH_SUCCESS;
 }
 
@@ -112,7 +112,7 @@ void ScreenMgrAdapter::RemoveScreenFromGroup(uint64_t screenId)
 
 int32_t ScreenMgrAdapter::RemoveVirtualScreen(uint64_t screenId)
 {
-    DHLOGI("remove virtual screen");
+    DHLOGI("remove virtual screen, screenId: %ulld", screenId);
     Rosen::DMError err = Rosen::ScreenManager::GetInstance().DestroyVirtualScreen(screenId);
     if (err != Rosen::DMError::DM_OK) {
         DHLOGE("remove virtual screen failed, screenId:%ulld", screenId);
diff --git a/services/screenservice/sourceservice/dscreenservice/include/callback/dscreen_source_callback_proxy.h b/services/screenservice/sourceservice/dscreenservice/include/callback/dscreen_source_callback_proxy.h
index aec646c2fbed9168145bd1164298c1730e4cdf0e..8a91b4130de274fa98b5f090ae61313f321f4787 100644
--- a/services/screenservice/sourceservice/dscreenservice/include/callback/dscreen_source_callback_proxy.h
+++ b/services/screenservice/sourceservice/dscreenservice/include/callback/dscreen_source_callback_proxy.h
@@ -37,6 +37,10 @@ public:
 
 private:
     static inline BrokerDelegator<DScreenSourceCallbackProxy> delegator_;
+    bool CheckParams(const std::string &devId, const std::string &dhId, const std::string &reqId,
+        const std::string &resultData);
+    const size_t DID_MAX_SIZE = 256;
+    const size_t PARAM_MAX_SIZE = 50 * 1024 * 1024;
 };
 } // namespace DistributedHardware
 } // namespace OHOS
diff --git a/services/screenservice/sourceservice/dscreenservice/include/dscreen_source_stub.h b/services/screenservice/sourceservice/dscreenservice/include/dscreen_source_stub.h
index 9ed200600a6cbba8329e08840c258e9654c5de1d..487d7e7f1632a55d53591558541c50392f68023b 100644
--- a/services/screenservice/sourceservice/dscreenservice/include/dscreen_source_stub.h
+++ b/services/screenservice/sourceservice/dscreenservice/include/dscreen_source_stub.h
@@ -42,10 +42,17 @@ private:
         MessageOption &option);
     int32_t DScreenNotifyInner(MessageParcel &data, MessageParcel &reply,
         MessageOption &option);
-
+    bool CheckRegParams(const std::string &devId, const std::string &dhId,
+        const std::string &version, const std::string &attrs, const std::string &reqId);
+    bool CheckUnregParams(const std::string &devId, const std::string &dhId, const std::string &reqId);
+    bool CheckConfigParams(const std::string &devId, const std::string &dhId,
+        const std::string &key, const std::string &value);
     using DScreenSourceFunc = int32_t (DScreenSourceStub::*)(MessageParcel &data, MessageParcel &reply,
         MessageOption &option);
     std::map<int32_t, DScreenSourceFunc> memberFuncMap_;
+
+    const size_t DID_MAX_SIZE = 256;
+    const size_t PARAM_MAX_SIZE = 50 * 1024 * 1024;
 };
 } // namespace DistributedHardware
 } // namespace OHOS
diff --git a/services/screenservice/sourceservice/dscreenservice/src/callback/dscreen_source_callback_proxy.cpp b/services/screenservice/sourceservice/dscreenservice/src/callback/dscreen_source_callback_proxy.cpp
index 508a0bbf148601974c2a338f712dc15e7ee94564..af76103f32695ca62b1911699f24dceaa12fdd64 100644
--- a/services/screenservice/sourceservice/dscreenservice/src/callback/dscreen_source_callback_proxy.cpp
+++ b/services/screenservice/sourceservice/dscreenservice/src/callback/dscreen_source_callback_proxy.cpp
@@ -26,6 +26,10 @@ namespace DistributedHardware {
 int32_t DScreenSourceCallbackProxy::OnNotifyRegResult(const std::string &devId, const std::string &dhId,
     const std::string &reqId, int32_t status, const std::string &resultData)
 {
+    if (!CheckParams(devId, dhId, reqId, resultData)) {
+        DHLOGE("OnNotifyRegResult error: invalid parameter.");
+        return ERR_DH_SCREEN_INPUT_PARAM_INVALID;
+    }
     sptr<IRemoteObject> remote = Remote();
     if (remote == nullptr) {
         DHLOGE("DScreenSourceCallbackProxy remote service null");
@@ -53,6 +57,10 @@ int32_t DScreenSourceCallbackProxy::OnNotifyRegResult(const std::string &devId,
 int32_t DScreenSourceCallbackProxy::OnNotifyUnregResult(const std::string &devId, const std::string &dhId,
     const std::string &reqId, int32_t status, const std::string &resultData)
 {
+    if (!CheckParams(devId, dhId, reqId, resultData)) {
+        DHLOGE("OnNotifyUnregResult error: invalid parameter.");
+        return ERR_DH_SCREEN_INPUT_PARAM_INVALID;
+    }
     sptr<IRemoteObject> remote = Remote();
     if (remote == nullptr) {
         DHLOGE("DScreenSourceCallbackProxy remote service null");
@@ -76,5 +84,19 @@ int32_t DScreenSourceCallbackProxy::OnNotifyUnregResult(const std::string &devId
     remote->SendRequest(NOTIFY_UNREG_RESULT, data, reply, option);
     return reply.ReadInt32();
 }
+
+bool DScreenSourceCallbackProxy::CheckParams(const std::string &devId, const std::string &dhId,
+    const std::string &reqId, const std::string &resultData)
+{
+    if (devId.empty() || devId.size() > DID_MAX_SIZE || dhId.empty() || dhId.size() > DID_MAX_SIZE) {
+        DHLOGE("DScreenSourceCallbackProxy CheckParams devId or dhId is invalid.");
+        return false;
+    }
+    if (reqId.empty() || reqId.size() > DID_MAX_SIZE || resultData.empty() || resultData.size() > PARAM_MAX_SIZE) {
+        DHLOGE("DScreenSourceCallbackProxy CheckParams reqId or resultData is invalid.");
+        return false;
+    }
+    return true;
+}
 } // namespace DistributedHardware
 } // namespace OHOS
\ No newline at end of file
diff --git a/services/screenservice/sourceservice/dscreenservice/src/dscreen_source_stub.cpp b/services/screenservice/sourceservice/dscreenservice/src/dscreen_source_stub.cpp
index d15449bf8206b4f65f97ff899b0160bcda8c69f4..e8fda0a48873a12e2d96447789c2c77a05b4d845 100644
--- a/services/screenservice/sourceservice/dscreenservice/src/dscreen_source_stub.cpp
+++ b/services/screenservice/sourceservice/dscreenservice/src/dscreen_source_stub.cpp
@@ -57,6 +57,10 @@ int32_t DScreenSourceStub::InitSourceInner(MessageParcel &data, MessageParcel &r
     MessageOption &option)
 {
     std::string param = data.ReadString();
+    if (param.empty() || param.size() > PARAM_MAX_SIZE) {
+        DHLOGE("InitSourceInner error: invalid parameter");
+        return ERR_DH_SCREEN_INPUT_PARAM_INVALID;
+    }
     sptr<IRemoteObject> remoteObject = data.ReadRemoteObject();
     if (remoteObject == nullptr) {
         DHLOGE("Read param failed.");
@@ -64,6 +68,10 @@ int32_t DScreenSourceStub::InitSourceInner(MessageParcel &data, MessageParcel &r
     }
 
     sptr<DScreenSourceCallbackProxy> dScreenSourceCallbackProxy(new DScreenSourceCallbackProxy(remoteObject));
+    if (dScreenSourceCallbackProxy == nullptr) {
+        DHLOGE("dScreenSourceCallbackProxy is nullptr.");
+        return ERR_DH_SCREEN_SA_READPARAM_FAILED;
+    }
     int32_t ret = InitSource(param, dScreenSourceCallbackProxy);
     reply.WriteInt32(ret);
     return DH_SUCCESS;
@@ -85,6 +93,10 @@ int32_t DScreenSourceStub::RegisterDistributedHardwareInner(MessageParcel &data,
     std::string version = data.ReadString();
     std::string attrs = data.ReadString();
     std::string reqId = data.ReadString();
+    if (!CheckRegParams(devId, dhId, version, attrs, reqId)) {
+        DHLOGE("RegisterDistributedHardwareInner error: invalid parameter");
+        return ERR_DH_SCREEN_INPUT_PARAM_INVALID;
+    }
     EnableParam enableParam;
     enableParam.version = version;
     enableParam.attrs = attrs;
@@ -100,6 +112,10 @@ int32_t DScreenSourceStub::UnregisterDistributedHardwareInner(MessageParcel &dat
     std::string devId = data.ReadString();
     std::string dhId = data.ReadString();
     std::string reqId = data.ReadString();
+    if (!CheckUnregParams(devId, dhId, reqId)) {
+        DHLOGE("UnregisterDistributedHardwareInner error: invalid parameter");
+        return ERR_DH_SCREEN_INPUT_PARAM_INVALID;
+    }
 
     int32_t ret = UnregisterDistributedHardware(devId, dhId, reqId);
     reply.WriteInt32(ret);
@@ -113,6 +129,10 @@ int32_t DScreenSourceStub::ConfigDistributedHardwareInner(MessageParcel &data, M
     std::string dhId = data.ReadString();
     std::string key = data.ReadString();
     std::string value = data.ReadString();
+    if (!CheckConfigParams(devId, dhId, key, value)) {
+        DHLOGE("ConfigDistributedHardwareInner error: invalid parameter");
+        return ERR_DH_SCREEN_INPUT_PARAM_INVALID;
+    }
 
     int32_t ret = ConfigDistributedHardware(devId, dhId, key, value);
     reply.WriteInt32(ret);
@@ -125,9 +145,59 @@ int32_t DScreenSourceStub::DScreenNotifyInner(MessageParcel &data, MessageParcel
     std::string devId = data.ReadString();
     int32_t eventCode = data.ReadInt32();
     std::string eventContent = data.ReadString();
+    if (devId.empty() || devId.size() > DID_MAX_SIZE || eventContent.empty() ||
+        eventContent.size() > PARAM_MAX_SIZE) {
+        DHLOGE("DScreenNotifyInner error: invalid parameter");
+        return ERR_DH_SCREEN_INPUT_PARAM_INVALID;
+    }
 
     DScreenNotify(devId, eventCode, eventContent);
     return DH_SUCCESS;
 }
+
+bool DScreenSourceStub::CheckRegParams(const std::string &devId, const std::string &dhId,
+    const std::string &version, const std::string &attrs, const std::string &reqId)
+{
+    if (devId.empty() || devId.size() > DID_MAX_SIZE || dhId.empty() || dhId.size() > DID_MAX_SIZE) {
+        DHLOGE("DScreenSourceStub CheckRegParams devId or dhId is inlvalid.");
+        return false;
+    }
+    if (version.empty() || version.size() > PARAM_MAX_SIZE || attrs.empty() || attrs.size() > PARAM_MAX_SIZE) {
+        DHLOGE("DScreenSourceStub CheckRegParams version or attrs is inlvalid.");
+        return false;
+    }
+    if (reqId.empty() || reqId.size() > DID_MAX_SIZE) {
+        DHLOGE("DScreenSourceStub CheckRegParams reqId is inlvalid.");
+        return false;
+    }
+    return true;
+}
+
+bool DScreenSourceStub::CheckUnregParams(const std::string &devId, const std::string &dhId, const std::string &reqId)
+{
+    if (devId.empty() || devId.size() > DID_MAX_SIZE || dhId.empty() || dhId.size() > DID_MAX_SIZE) {
+        DHLOGE("DScreenSourceStub CheckUnregParams devId or dhId is invalid.");
+        return false;
+    }
+    if (reqId.empty() || reqId.size() > DID_MAX_SIZE) {
+        DHLOGE("DScreenSourceStub CheckUnregParams reqId is invalid.");
+        return false;
+    }
+    return true;
+}
+
+bool DScreenSourceStub::CheckConfigParams(const std::string &devId, const std::string &dhId,
+    const std::string &key, const std::string &value)
+{
+    if (devId.empty() || devId.size() > DID_MAX_SIZE || dhId.empty() || dhId.size() > DID_MAX_SIZE) {
+        DHLOGE("DScreenSourceStub CheckConfigParams devId or dhId is invalid.");
+        return false;
+    }
+    if (key.empty() || key.size() > PARAM_MAX_SIZE || value.empty() || value.size() > PARAM_MAX_SIZE) {
+        DHLOGE("DScreenSourceStub CheckConfigParams key or value is invalid.");
+        return false;
+    }
+    return true;
+}
 } // namespace DistributedHardware
 } // namespace OHOS
\ No newline at end of file
diff --git a/services/screentransport/screensinktrans/src/screen_sink_trans.cpp b/services/screentransport/screensinktrans/src/screen_sink_trans.cpp
index 8a7395f5ea96001b96d5c26ec8923fb4517c8a76..0728bdb8e47504217a03762c59c1d5cf669924f9 100644
--- a/services/screentransport/screensinktrans/src/screen_sink_trans.cpp
+++ b/services/screentransport/screensinktrans/src/screen_sink_trans.cpp
@@ -47,7 +47,7 @@ int32_t ScreenSinkTrans::SetUp(const VideoParam &localParam, const VideoParam &r
 int32_t ScreenSinkTrans::Release()
 {
     DHLOGI("%s: Release.", LOG_TAG);
-    if (!imageProcessor_ || !screenChannel_) {
+    if (imageProcessor_ ==nullptr || screenChannel_ == nullptr) {
         DHLOGE("%s: Processor or channel is null, Setup first.", LOG_TAG);
         return ERR_DH_SCREEN_TRANS_NULL_VALUE;
     }
@@ -73,7 +73,7 @@ int32_t ScreenSinkTrans::Release()
 int32_t ScreenSinkTrans::Start()
 {
     DHLOGI("%s: Start.", LOG_TAG);
-    if (!imageProcessor_ || !screenChannel_) {
+    if (imageProcessor_ == nullptr || screenChannel_ == nullptr) {
         DHLOGE("%s: Processor or channel is null, Setup first.", LOG_TAG);
         return ERR_DH_SCREEN_TRANS_NULL_VALUE;
     }
@@ -91,7 +91,7 @@ int32_t ScreenSinkTrans::Start()
 int32_t ScreenSinkTrans::Stop()
 {
     DHLOGI("%s: Stop.", LOG_TAG);
-    if (!imageProcessor_ || !screenChannel_) {
+    if (imageProcessor_ == nullptr || screenChannel_ == nullptr) {
         DHLOGE("%s: Processor or channel is null, Setup first.", LOG_TAG);
         return ERR_DH_SCREEN_TRANS_NULL_VALUE;
     }
@@ -123,7 +123,7 @@ int32_t ScreenSinkTrans::Stop()
 int32_t ScreenSinkTrans::RegisterStateCallback(const std::shared_ptr<IScreenSinkTransCallback> &callback)
 {
     DHLOGI("%s:RegisterStateCallback.", LOG_TAG);
-    if (!callback) {
+    if (callback == nullptr) {
         DHLOGE("%s: Trans callback is null.", LOG_TAG);
         return ERR_DH_SCREEN_TRANS_NULL_VALUE;
     }
@@ -134,7 +134,7 @@ int32_t ScreenSinkTrans::RegisterStateCallback(const std::shared_ptr<IScreenSink
 
 int32_t ScreenSinkTrans::SetImageSurface(const sptr<Surface> &surface)
 {
-    if (!surface) {
+    if (surface == nullptr) {
         DHLOGE("%s: Image surface is null.", LOG_TAG);
         return ERR_DH_SCREEN_TRANS_NULL_VALUE;
     }
@@ -208,7 +208,7 @@ int32_t ScreenSinkTrans::InitScreenTrans(const VideoParam &localParam, const Vid
     const std::string &peerDevId)
 {
     screenChannel_ = std::make_shared<ScreenDataChannelImpl>(peerDevId);
-    if (!screenChannel_) {
+    if (screenChannel_ == nullptr) {
         DHLOGE("%s: Create screen data channel failed.", LOG_TAG);
         return ERR_DH_SCREEN_TRANS_NULL_VALUE;
     }
@@ -220,7 +220,7 @@ int32_t ScreenSinkTrans::InitScreenTrans(const VideoParam &localParam, const Vid
     }
 
     imageProcessor_ = std::make_shared<ImageSinkProcessor>();
-    if (!imageProcessor_) {
+    if (imageProcessor_ == nullptr) {
         DHLOGE("%s: Create image processor failed.", LOG_TAG);
         screenChannel_ = nullptr;
         return ERR_DH_SCREEN_TRANS_NULL_VALUE;
@@ -240,7 +240,7 @@ int32_t ScreenSinkTrans::RegisterChannelListener()
 {
     DHLOGI("%s: RegisterChannelListener.", LOG_TAG);
     std::shared_ptr<IScreenChannelListener> listener = shared_from_this();
-    if (!listener) {
+    if (listener == nullptr) {
         DHLOGE("%s: Channel Listener is null.", LOG_TAG);
         return ERR_DH_SCREEN_TRANS_NULL_VALUE;
     }
@@ -260,7 +260,7 @@ int32_t ScreenSinkTrans::RegisterProcessorListener(const VideoParam &localParam,
 {
     DHLOGI("%s: RegisterProcessorListener.", LOG_TAG);
     std::shared_ptr<IImageSinkProcessorListener> listener = shared_from_this();
-    if (!listener) {
+    if (listener == nullptr) {
         DHLOGE("%s: Channel listener to null.", LOG_TAG);
         return ERR_DH_SCREEN_TRANS_NULL_VALUE;
     }
@@ -289,7 +289,7 @@ void ScreenSinkTrans::OnSessionClosed()
 {
     DHLOGI("%s:OnChannelSessionClosed.", LOG_TAG);
     std::shared_ptr<IScreenSinkTransCallback> callback = transCallback_.lock();
-    if (!callback) {
+    if (callback == nullptr) {
         DHLOGE("%s: Trans callback is null.", LOG_TAG);
         return;
     }
@@ -309,7 +309,7 @@ void ScreenSinkTrans::OnProcessorStateNotify(int32_t state)
 {
     DHLOGI("%s: OnProcessorStateNotify.", LOG_TAG);
     std::shared_ptr<IScreenSinkTransCallback> callback = transCallback_.lock();
-    if (!callback) {
+    if (callback == nullptr) {
         DHLOGE("%s: Trans callback is null.", LOG_TAG);
         return;
     }
diff --git a/services/screentransport/screensourceprocessor/encoder/include/image_source_encoder.h b/services/screentransport/screensourceprocessor/encoder/include/image_source_encoder.h
index 88c6ce5fed0d0760646781efbb778037b1e1ef6c..781ba1719e2451c31263f74e8d5014ee52c0c9cf 100644
--- a/services/screentransport/screensourceprocessor/encoder/include/image_source_encoder.h
+++ b/services/screentransport/screensourceprocessor/encoder/include/image_source_encoder.h
@@ -66,6 +66,7 @@ private:
     std::shared_ptr<Media::AVSharedMemory> videoSharedMemory_;
     std::shared_ptr<Media::AVCodecCallback> encodeVideoCallback_;
     std::weak_ptr<IImageSourceProcessorListener> imageProcessorListener_;
+    const size_t DATA_BUFFER_MAX_SIZE = 10 * 1024 * 1024;
 };
 } // namespace DistributedHardware
 } // namespace OHOS
diff --git a/services/screentransport/screensourceprocessor/encoder/src/image_source_encoder.cpp b/services/screentransport/screensourceprocessor/encoder/src/image_source_encoder.cpp
index 77c04caa7f578d452c284faca45cdd914ec5d243..a265b8dca412a41f98d49063c2d616ddd2d8327d 100644
--- a/services/screentransport/screensourceprocessor/encoder/src/image_source_encoder.cpp
+++ b/services/screentransport/screensourceprocessor/encoder/src/image_source_encoder.cpp
@@ -231,6 +231,10 @@ void ImageSourceEncoder::OnOutputBufferAvailable(uint32_t index, Media::AVCodecB
     }
 
     size_t dataSize = static_cast<size_t>(info.size);
+    if (dataSize <= 0 || dataSize > DATA_BUFFER_MAX_SIZE) {
+        DHLOGE("%s:OnOutputBufferAvailable params invalid, size: %d.", LOG_TAG, dataSize);
+        return;
+    }
     auto dataBuf = std::make_shared<DataBuffer>(dataSize);
     if (dataBuf == nullptr) {
         DHLOGE("%s: Create buffer failed.", LOG_TAG);
diff --git a/services/softbusadapter/src/softbus_adapter.cpp b/services/softbusadapter/src/softbus_adapter.cpp
index 503c226ffa09e2cbb8f5665e566f79ee19a31e1d..c4814ab4acc6565ab222ef7415f5a64d649837e1 100644
--- a/services/softbusadapter/src/softbus_adapter.cpp
+++ b/services/softbusadapter/src/softbus_adapter.cpp
@@ -78,6 +78,10 @@ SoftbusAdapter::~SoftbusAdapter()
 int32_t SoftbusAdapter::RegisterSoftbusListener(const std::shared_ptr<ISoftbusListener> &listener,
     const std::string &sessionName, const std::string &peerDevId)
 {
+    if (listener == nullptr) {
+        DHLOGE("%s: listener is nullptr.", LOG_TAG);
+        return ERR_DH_SCREEN_ADAPTER_REGISTER_SOFTBUS_LISTENER_FAIL;
+    }
     DHLOGI("%s: RegisterListener sess:%s id:%s.", LOG_TAG, sessionName.c_str(), GetAnonyString(peerDevId).c_str());
     std::string strListenerKey = sessionName + "_" + peerDevId;