diff --git a/core/src/main/java/org/lsposed/lspd/util/InstallerVerifier.java b/core/src/main/java/org/lsposed/lspd/util/InstallerVerifier.java
index 7dfb44c8..507e2d89 100644
--- a/core/src/main/java/org/lsposed/lspd/util/InstallerVerifier.java
+++ b/core/src/main/java/org/lsposed/lspd/util/InstallerVerifier.java
@@ -26,17 +26,15 @@ import de.robv.android.xposed.XposedHelpers;
 
 public class InstallerVerifier {
 
-    public static boolean sendBinderToManager(final ClassLoader classLoader, IBinder binder) {
-        Utils.logI("Found LSPosed Manager");
+    public static void sendBinderToManager(final ClassLoader classLoader, IBinder binder) {
         try {
             var clazz = XposedHelpers.findClass("org.lsposed.manager.Constants", classLoader);
-            var ret = (boolean) XposedHelpers.callStaticMethod(clazz, "setBinder",
+            var ok = (boolean) XposedHelpers.callStaticMethod(clazz, "setBinder",
                     new Class[]{IBinder.class}, binder);
-            Utils.logI("Send binder to LSPosed Manager: " + ret);
-            return ret;
+            if (ok) return;
+            throw new RuntimeException("setBinder: " + false);
         } catch (Throwable t) {
             Utils.logW("Could not send binder to LSPosed Manager", t);
-            return false;
         }
     }
 }
diff --git a/daemon/src/main/java/org/lsposed/lspd/service/ConfigFileManager.java b/daemon/src/main/java/org/lsposed/lspd/service/ConfigFileManager.java
index ea2d5aa2..a7cffb57 100644
--- a/daemon/src/main/java/org/lsposed/lspd/service/ConfigFileManager.java
+++ b/daemon/src/main/java/org/lsposed/lspd/service/ConfigFileManager.java
@@ -156,7 +156,7 @@ public class ConfigFileManager {
 
     static ParcelFileDescriptor getManagerApk() throws IOException {
         if (fd != null) return fd.dup();
-        if (!InstallerVerifier.verifyInstallerSignature(managerApkPath.toString())) return null;
+        InstallerVerifier.verifyInstallerSignature(managerApkPath.toString());
 
         SELinux.setFileContext(managerApkPath.toString(), "u:object_r:system_file:s0");
         fd = ParcelFileDescriptor.open(managerApkPath.toFile(), ParcelFileDescriptor.MODE_READ_ONLY);
diff --git a/daemon/src/main/java/org/lsposed/lspd/util/InstallerVerifier.java b/daemon/src/main/java/org/lsposed/lspd/util/InstallerVerifier.java
index e174e8f7..1d6b81d1 100644
--- a/daemon/src/main/java/org/lsposed/lspd/util/InstallerVerifier.java
+++ b/daemon/src/main/java/org/lsposed/lspd/util/InstallerVerifier.java
@@ -1,29 +1,31 @@
 package org.lsposed.lspd.util;
 
+import static org.lsposed.lspd.util.SignInfo.CERTIFICATE;
+
 import com.android.apksig.ApkVerifier;
 
 import java.io.File;
+import java.io.IOException;
 import java.util.Arrays;
 
-import static org.lsposed.lspd.util.SignInfo.CERTIFICATE;
-
 public class InstallerVerifier {
 
-    public static boolean verifyInstallerSignature(String path) {
+    public static void verifyInstallerSignature(String path) throws IOException {
         ApkVerifier verifier = new ApkVerifier.Builder(new File(path))
                 .setMinCheckedPlatformVersion(27)
                 .build();
         try {
             ApkVerifier.Result result = verifier.verify();
             if (!result.isVerified()) {
-                return false;
+                throw new IOException("apk signature not verified");
             }
-            boolean ret = Arrays.equals(result.getSignerCertificates().get(0).getEncoded(), CERTIFICATE);
-            Utils.logI("verifyInstallerSignature: " + ret);
-            return ret;
-        } catch (Throwable t) {
-            Utils.logE("verifyInstallerSignature: ", t);
-            return false;
+            var mainCert = result.getSignerCertificates().get(0);
+            if (!Arrays.equals(mainCert.getEncoded(), CERTIFICATE)) {
+                var dname = mainCert.getSubjectX500Principal().getName();
+                throw new IOException("apk signature mismatch: " + dname);
+            }
+        } catch (Exception t) {
+            throw new IOException(t);
         }
     }
 }
diff --git a/magisk-loader/src/main/java/org/lsposed/lspd/util/ParasiticManagerHooker.java b/magisk-loader/src/main/java/org/lsposed/lspd/util/ParasiticManagerHooker.java
index c7cdc566..e2d6fa93 100644
--- a/magisk-loader/src/main/java/org/lsposed/lspd/util/ParasiticManagerHooker.java
+++ b/magisk-loader/src/main/java/org/lsposed/lspd/util/ParasiticManagerHooker.java
@@ -141,7 +141,7 @@ public class ParasiticManagerHooker {
                 }
                 if (param.method.getName().equals("scheduleLaunchActivity")) {
                     ActivityInfo aInfo = null;
-                    var parameters = ((Method)param.method).getParameterTypes();
+                    var parameters = ((Method) param.method).getParameterTypes();
                     for (var i = 0; i < parameters.length; ++i) {
                         if (parameters[i] == ActivityInfo.class) {
                             aInfo = (ActivityInfo) param.args[i];
@@ -317,9 +317,8 @@ public class ParasiticManagerHooker {
 
 
     static public boolean start() {
-        try {
-            List<IBinder> binder = new ArrayList<>(1);
-            var managerParcelFd = serviceClient.requestInjectedManagerBinder(binder);
+        List<IBinder> binder = new ArrayList<>(1);
+        try (var managerParcelFd = serviceClient.requestInjectedManagerBinder(binder)) {
             if (binder.size() > 0 && binder.get(0) != null && managerParcelFd != null) {
                 managerFd = managerParcelFd.detachFd();
                 var managerService = ILSPManagerService.Stub.asInterface(binder.get(0));