在 checkPermission 方法中加载一些 class 时，为什么 SecurityManager 会发出递归更新异常？

Question

我正在将 jdk 8 升级到 11。

我在 checkPermission 方法中加载了一些 class，然后安全管理器发出 recursive update 异常。但使用 jdk1.8.0_202 一切正常。

导致此问题的原因是什么？

我的环境。

OS: macOS 10.15.6
JDK(Oracle): 11.0.8
IDE: Intellij 2019 3

主要

public class Main {
    public static void main(String[] args) {
        System.out.println("Hello world");
    }
}

安全管理器

package sm;

import java.security.Permission;

public class MySecurityManager extends SecurityManager {

    @Override
    public void checkPermission(Permission permission) {

        // Problem occurs when load ServicePermission.class
        if (permission instanceof javax.security.auth.kerberos.ServicePermission) {
            // throw new SecurityException("javax.security.auth.kerberos.ServicePermission is not allowed.");
        }
    }

    @Override
    public void checkPermission(Permission permission, Object context) {
        this.checkPermission(permission);
    }
}

运行与 -Djava.security.manager=sm.MySecurityManager
控制台日志

Error occurred during initialization of VM
java.lang.BootstrapMethodError: bootstrap method initialization exception
    at java.lang.invoke.BootstrapMethodInvoker.invoke(java.base@11.0.8/BootstrapMethodInvoker.java:194)
    at java.lang.invoke.CallSite.makeSite(java.base@11.0.8/CallSite.java:307)
    at java.lang.invoke.MethodHandleNatives.linkCallSiteImpl(java.base@11.0.8/MethodHandleNatives.java:258)
    at java.lang.invoke.MethodHandleNatives.linkCallSite(java.base@11.0.8/MethodHandleNatives.java:248)
    at sun.net.www.protocol.jrt.JavaRuntimeURLConnection.<clinit>(java.base@11.0.8/JavaRuntimeURLConnection.java:55)
    at sun.net.www.protocol.jrt.Handler.openConnection(java.base@11.0.8/Handler.java:42)
    at java.net.URL.openConnection(java.base@11.0.8/URL.java:1074)
    at jdk.internal.module.SystemModuleFinders$SystemModuleReader.checkPermissionToConnect(java.base@11.0.8/SystemModuleFinders.java:405)
    at jdk.internal.module.SystemModuleFinders$SystemModuleReader.<init>(java.base@11.0.8/SystemModuleFinders.java:414)
    at jdk.internal.module.SystemModuleFinders.get(java.base@11.0.8/SystemModuleFinders.java:315)
    at jdk.internal.module.SystemModuleFinders.get(java.base@11.0.8/SystemModuleFinders.java:312)
    at jdk.internal.module.ModuleReferenceImpl.open(java.base@11.0.8/ModuleReferenceImpl.java:93)
    at jdk.internal.loader.BuiltinClassLoader.apply(java.base@11.0.8/BuiltinClassLoader.java:961)
    at jdk.internal.loader.BuiltinClassLoader.apply(java.base@11.0.8/BuiltinClassLoader.java:958)
    at java.util.concurrent.ConcurrentHashMap.computeIfAbsent(java.base@11.0.8/ConcurrentHashMap.java:1705)
    at jdk.internal.loader.BuiltinClassLoader.moduleReaderFor(java.base@11.0.8/BuiltinClassLoader.java:969)
    at jdk.internal.loader.BuiltinClassLoader.defineClass(java.base@11.0.8/BuiltinClassLoader.java:731)
    at jdk.internal.loader.BuiltinClassLoader.lambda$findClassInModuleOrNull(java.base@11.0.8/BuiltinClassLoader.java:682)
    at java.security.AccessController.doPrivileged(java.base@11.0.8/Native Method)
    at jdk.internal.loader.BuiltinClassLoader.findClassInModuleOrNull(java.base@11.0.8/BuiltinClassLoader.java:683)
    at jdk.internal.loader.BuiltinClassLoader.loadClassOrNull(java.base@11.0.8/BuiltinClassLoader.java:605)
    at jdk.internal.loader.BuiltinClassLoader.loadClassOrNull(java.base@11.0.8/BuiltinClassLoader.java:640)
    at jdk.internal.loader.BuiltinClassLoader.loadClassOrNull(java.base@11.0.8/BuiltinClassLoader.java:609)
    at jdk.internal.loader.BuiltinClassLoader.loadClass(java.base@11.0.8/BuiltinClassLoader.java:579)
    at jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(java.base@11.0.8/ClassLoaders.java:178)
    at java.lang.ClassLoader.loadClass(java.base@11.0.8/ClassLoader.java:521)
    at sm.MySecurityManager.checkPermission(MySecurityManager.java:11)
    at java.lang.SecurityManager.checkPropertyAccess(java.base@11.0.8/SecurityManager.java:1066)
    at java.lang.System.getProperty(java.base@11.0.8/System.java:814)
    at java.lang.ClassLoader.initSystemClassLoader(java.base@11.0.8/ClassLoader.java:1971)
    at java.lang.System.initPhase3(java.base@11.0.8/System.java:2070)
Caused by: java.lang.IllegalStateException: Recursive update
    at java.util.concurrent.ConcurrentHashMap.computeIfAbsent(java.base@11.0.8/ConcurrentHashMap.java:1760)
    at jdk.internal.loader.BuiltinClassLoader.moduleReaderFor(java.base@11.0.8/BuiltinClassLoader.java:969)
    at jdk.internal.loader.BuiltinClassLoader.defineClass(java.base@11.0.8/BuiltinClassLoader.java:731)
    at jdk.internal.loader.BuiltinClassLoader.lambda$findClassInModuleOrNull(java.base@11.0.8/BuiltinClassLoader.java:682)
    at java.security.AccessController.doPrivileged(java.base@11.0.8/Native Method)
    at jdk.internal.loader.BuiltinClassLoader.findClassInModuleOrNull(java.base@11.0.8/BuiltinClassLoader.java:683)
    at jdk.internal.loader.BuiltinClassLoader.loadClassOrNull(java.base@11.0.8/BuiltinClassLoader.java:605)
    at jdk.internal.loader.BuiltinClassLoader.loadClassOrNull(java.base@11.0.8/BuiltinClassLoader.java:640)
    at jdk.internal.loader.BuiltinClassLoader.loadClassOrNull(java.base@11.0.8/BuiltinClassLoader.java:609)
    at jdk.internal.loader.BuiltinClassLoader.loadClass(java.base@11.0.8/BuiltinClassLoader.java:579)
    at jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(java.base@11.0.8/ClassLoaders.java:178)
    at java.lang.ClassLoader.loadClass(java.base@11.0.8/ClassLoader.java:521)
    at sm.MySecurityManager.checkPermission(MySecurityManager.java:11)
    at java.lang.reflect.AccessibleObject.checkPermission(java.base@11.0.8/AccessibleObject.java:83)
    at java.lang.reflect.Constructor.setAccessible(java.base@11.0.8/Constructor.java:180)
    at java.lang.invoke.InnerClassLambdaMetafactory.run(java.base@11.0.8/InnerClassLambdaMetafactory.java:206)
    at java.lang.invoke.InnerClassLambdaMetafactory.run(java.base@11.0.8/InnerClassLambdaMetafactory.java:199)
    at java.security.AccessController.doPrivileged(java.base@11.0.8/Native Method)
    at java.lang.invoke.InnerClassLambdaMetafactory.buildCallSite(java.base@11.0.8/InnerClassLambdaMetafactory.java:198)
    at java.lang.invoke.LambdaMetafactory.metafactory(java.base@11.0.8/LambdaMetafactory.java:329)
    at java.lang.invoke.BootstrapMethodInvoker.invoke(java.base@11.0.8/BootstrapMethodInvoker.java:127)
    at java.lang.invoke.CallSite.makeSite(java.base@11.0.8/CallSite.java:307)
    at java.lang.invoke.MethodHandleNatives.linkCallSiteImpl(java.base@11.0.8/MethodHandleNatives.java:258)
    at java.lang.invoke.MethodHandleNatives.linkCallSite(java.base@11.0.8/MethodHandleNatives.java:248)
    at sun.net.www.protocol.jrt.JavaRuntimeURLConnection.<clinit>(java.base@11.0.8/JavaRuntimeURLConnection.java:55)
    at sun.net.www.protocol.jrt.Handler.openConnection(java.base@11.0.8/Handler.java:42)
    at java.net.URL.openConnection(java.base@11.0.8/URL.java:1074)
    at jdk.internal.module.SystemModuleFinders$SystemModuleReader.checkPermissionToConnect(java.base@11.0.8/SystemModuleFinders.java:405)
    at jdk.internal.module.SystemModuleFinders$SystemModuleReader.<init>(java.base@11.0.8/SystemModuleFinders.java:414)
    at jdk.internal.module.SystemModuleFinders.get(java.base@11.0.8/SystemModuleFinders.java:315)
    at jdk.internal.module.SystemModuleFinders.get(java.base@11.0.8/SystemModuleFinders.java:312)
    at jdk.internal.module.ModuleReferenceImpl.open(java.base@11.0.8/ModuleReferenceImpl.java:93)
    at jdk.internal.loader.BuiltinClassLoader.apply(java.base@11.0.8/BuiltinClassLoader.java:961)
    at jdk.internal.loader.BuiltinClassLoader.apply(java.base@11.0.8/BuiltinClassLoader.java:958)
    at java.util.concurrent.ConcurrentHashMap.computeIfAbsent(java.base@11.0.8/ConcurrentHashMap.java:1705)
    at jdk.internal.loader.BuiltinClassLoader.moduleReaderFor(java.base@11.0.8/BuiltinClassLoader.java:969)
    at jdk.internal.loader.BuiltinClassLoader.defineClass(java.base@11.0.8/BuiltinClassLoader.java:731)
    at jdk.internal.loader.BuiltinClassLoader.lambda$findClassInModuleOrNull(java.base@11.0.8/BuiltinClassLoader.java:682)
    at java.security.AccessController.doPrivileged(java.base@11.0.8/Native Method)
    at jdk.internal.loader.BuiltinClassLoader.findClassInModuleOrNull(java.base@11.0.8/BuiltinClassLoader.java:683)
    at jdk.internal.loader.BuiltinClassLoader.loadClassOrNull(java.base@11.0.8/BuiltinClassLoader.java:605)
    at jdk.internal.loader.BuiltinClassLoader.loadClassOrNull(java.base@11.0.8/BuiltinClassLoader.java:640)
    at jdk.internal.loader.BuiltinClassLoader.loadClassOrNull(java.base@11.0.8/BuiltinClassLoader.java:609)
    at jdk.internal.loader.BuiltinClassLoader.loadClass(java.base@11.0.8/BuiltinClassLoader.java:579)
    at jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(java.base@11.0.8/ClassLoaders.java:178)
    at java.lang.ClassLoader.loadClass(java.base@11.0.8/ClassLoader.java:521)
    at sm.MySecurityManager.checkPermission(MySecurityManager.java:11)
    at java.lang.SecurityManager.checkPropertyAccess(java.base@11.0.8/SecurityManager.java:1066)
    at java.lang.System.getProperty(java.base@11.0.8/System.java:814)
    at java.lang.ClassLoader.initSystemClassLoader(java.base@11.0.8/ClassLoader.java:1971)
    at java.lang.System.initPhase3(java.base@11.0.8/System.java:2070)


Process finished with exit code 1

Answer 1

堆栈跟踪表明问题与 模块加载 而不是 class 加载有关，这解释了为什么 [=] 中没有问题53=] 8 没有模块。

当您从底部开始读取堆栈跟踪时，即

    at java.lang.System.initPhase3(java.base@11.0.8/System.java:2070)

你会遇到栈帧

    at java.util.concurrent.ConcurrentHashMap.computeIfAbsent(java.base@11.0.8/ConcurrentHashMap.java:1705)
    at jdk.internal.loader.BuiltinClassLoader.moduleReaderFor(java.base@11.0.8/BuiltinClassLoader.java:969)

表示试图加载模块。这最终将以需要检查的特权操作结束，因此您会找到行

    at sm.MySecurityManager.checkPermission(MySecurityManager.java:11)

这会触发模块 java.security.jgss 中的 javax.security.auth.kerberos.ServicePermission 的加载，显然以前没有加载过。

因此 loadClass 通话再次结束于

    at java.util.concurrent.ConcurrentHashMap.computeIfAbsent(java.base@11.0.8/ConcurrentHashMap.java:1760)
    at jdk.internal.loader.BuiltinClassLoader.moduleReaderFor(java.base@11.0.8/BuiltinClassLoader.java:969)

这会触发“java.lang.IllegalStateException：递归更新”，因为不允许从另一个 computeIfAbsent 对同一 ConcurrentHashMap 的调用调用 computeIfAbsent。由于忽略此约束会导致地图损坏，因此在 Java 9 中添加了一项检查以拒绝此类尝试。参见。

通常，从可能在 class 加载期间再次检查的安全管理器触发 class 加载可能会出现问题。我建议求助于 documented toString() output 进行比较。毕竟，这也是基于策略文件的安全实现所做的。

因为 ServicePermission 是 final，所以更便宜的 permission.getClass().getName().equals( "javax.security.auth.kerberos.ServicePermission") 也可以。如果以前没有使用过，这两种方法都会避免加载权限。如问题所示，这甚至可以节省整个模块的加载。

在 checkPermission 方法中加载一些 class 时，为什么 SecurityManager 会发出递归更新异常？

When load some class in checkPermission method why SecurityManager emit recursive update exception?

java

securitymanager

java-security-manager

java-11