Merge "Add a runtime check to ensure that system server jars are prefetched."

This commit is contained in:
Treehugger Robot
2022-02-25 13:44:34 +00:00
committed by Gerrit Code Review
5 changed files with 131 additions and 12 deletions

View File

@@ -29,22 +29,66 @@ public final class SystemServerClassLoaderFactory {
private static final ArrayMap<String, PathClassLoader> sLoadedPaths = new ArrayMap<>();
/**
* Creates and caches a ClassLoader for the jar at the given path, or returns a cached
* ClassLoader if it exists.
* Creates and caches a ClassLoader for the jar at the given path.
*
* This method should only be called by ZygoteInit to prefetch jars. For other users, use
* {@link getOrCreateClassLoader} instead.
*
* The parent class loader should always be the system server class loader. Changing it has
* implications that require discussion with the mainline team.
*
* @hide for internal use only
*/
public static PathClassLoader getOrCreateClassLoader(String path, ClassLoader parent) {
PathClassLoader pathClassLoader = sLoadedPaths.get(path);
if (pathClassLoader == null) {
pathClassLoader = (PathClassLoader) ClassLoaderFactory.createClassLoader(
path, /*librarySearchPath=*/null, /*libraryPermittedPath=*/null, parent,
Build.VERSION.SDK_INT, /*isNamespaceShared=*/true , /*classLoaderName=*/null);
sLoadedPaths.put(path, pathClassLoader);
/* package */ static PathClassLoader createClassLoader(String path, ClassLoader parent) {
if (sLoadedPaths.containsKey(path)) {
throw new IllegalStateException("A ClassLoader for " + path + " already exists");
}
PathClassLoader pathClassLoader = (PathClassLoader) ClassLoaderFactory.createClassLoader(
path, /*librarySearchPath=*/null, /*libraryPermittedPath=*/null, parent,
Build.VERSION.SDK_INT, /*isNamespaceShared=*/true , /*classLoaderName=*/null);
sLoadedPaths.put(path, pathClassLoader);
return pathClassLoader;
}
/**
* Returns a cached ClassLoader to be used at runtime for the jar at the given path. Or, creates
* one if it is not prefetched and is allowed to be created at runtime.
*
* The parent class loader should always be the system server class loader. Changing it has
* implications that require discussion with the mainline team.
*
* @hide for internal use only
*/
public static PathClassLoader getOrCreateClassLoader(
String path, ClassLoader parent, boolean isTestOnly) {
PathClassLoader pathClassLoader = sLoadedPaths.get(path);
if (pathClassLoader != null) {
return pathClassLoader;
}
if (!allowClassLoaderCreation(path, isTestOnly)) {
throw new RuntimeException("Creating a ClassLoader from " + path + " is not allowed. "
+ "Please make sure that the jar is listed in "
+ "`PRODUCT_APEX_STANDALONE_SYSTEM_SERVER_JARS` in the Makefile and added as a "
+ "`standalone_contents` of a `systemserverclasspath_fragment` in "
+ "`Android.bp`.");
}
return createClassLoader(path, parent);
}
/**
* Returns whether a class loader for the jar is allowed to be created at runtime.
*/
private static boolean allowClassLoaderCreation(String path, boolean isTestOnly) {
// Currently, we only enforce prefetching for APEX jars.
if (!path.startsWith("/apex/")) {
return true;
}
// APEXes for testing only are okay to ignore.
if (isTestOnly) {
return true;
}
return false;
}
}

View File

@@ -586,7 +586,7 @@ public class ZygoteInit {
}
for (String jar : envStr.split(":")) {
try {
SystemServerClassLoaderFactory.getOrCreateClassLoader(
SystemServerClassLoaderFactory.createClassLoader(
jar, getOrCreateSystemServerClassLoader());
} catch (Error e) {
// We don't want the process to crash for this error because prefetching is just an

View File

@@ -20,6 +20,8 @@ import android.annotation.NonNull;
import android.annotation.Nullable;
import android.annotation.UserIdInt;
import android.content.Context;
import android.content.pm.ApplicationInfo;
import android.content.pm.PackageInfo;
import android.content.pm.UserInfo;
import android.os.Environment;
import android.os.SystemClock;
@@ -34,6 +36,7 @@ import com.android.internal.os.SystemServerClassLoaderFactory;
import com.android.internal.util.Preconditions;
import com.android.server.SystemService.TargetUser;
import com.android.server.am.EventLogTags;
import com.android.server.pm.ApexManager;
import com.android.server.pm.UserManagerInternal;
import com.android.server.utils.TimingsTraceAndSlog;
@@ -42,6 +45,8 @@ import dalvik.system.PathClassLoader;
import java.io.File;
import java.lang.reflect.Constructor;
import java.lang.reflect.InvocationTargetException;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.ArrayList;
/**
@@ -114,12 +119,31 @@ public final class SystemServiceManager implements Dumpable {
* @return The service instance.
*/
public SystemService startServiceFromJar(String className, String path) {
PathClassLoader pathClassLoader = SystemServerClassLoaderFactory.getOrCreateClassLoader(
path, this.getClass().getClassLoader());
PathClassLoader pathClassLoader =
SystemServerClassLoaderFactory.getOrCreateClassLoader(
path, this.getClass().getClassLoader(), isJarInTestApex(path));
final Class<SystemService> serviceClass = loadClassFromLoader(className, pathClassLoader);
return startService(serviceClass);
}
/**
* Returns true if the jar is in a test APEX.
*/
private static boolean isJarInTestApex(String pathStr) {
Path path = Paths.get(pathStr);
if (path.getNameCount() >= 2 && path.getName(0).toString().equals("apex")) {
String apexModuleName = path.getName(1).toString();
ApexManager apexManager = ApexManager.getInstance();
String packageName = apexManager.getActivePackageNameForApexModuleName(apexModuleName);
PackageInfo packageInfo = apexManager.getPackageInfo(
packageName, ApexManager.MATCH_ACTIVE_PACKAGE);
if (packageInfo != null) {
return (packageInfo.applicationInfo.flags & ApplicationInfo.FLAG_TEST_ONLY) != 0;
}
}
return false;
}
/*
* Loads and initializes a class from the given classLoader. Returns the class.
*/

View File

@@ -342,6 +342,13 @@ public abstract class ApexManager {
@Nullable
public abstract String getApexModuleNameForPackageName(String apexPackageName);
/**
* Returns the package name of the active APEX whose name is {@code apexModuleName}. If not
* found, returns {@code null}.
*/
@Nullable
public abstract String getActivePackageNameForApexModuleName(String apexModuleName);
/**
* Copies the CE apex data directory for the given {@code userId} to a backup location, for use
* in case of rollback.
@@ -466,6 +473,12 @@ public abstract class ApexManager {
@GuardedBy("mLock")
private ArrayMap<String, String> mPackageNameToApexModuleName;
/**
* Reverse mapping of {@link #mPackageNameToApexModuleName}, for active packages only.
*/
@GuardedBy("mLock")
private ArrayMap<String, String> mApexModuleNameToActivePackageName;
/**
* Whether an APEX package is active or not.
*
@@ -534,6 +547,7 @@ public abstract class ApexManager {
try {
mAllPackagesCache = new ArrayList<>();
mPackageNameToApexModuleName = new ArrayMap<>();
mApexModuleNameToActivePackageName = new ArrayMap<>();
allPkgs = waitForApexService().getAllPackages();
} catch (RemoteException re) {
Slog.e(TAG, "Unable to retrieve packages from apexservice: " + re.toString());
@@ -580,6 +594,13 @@ public abstract class ApexManager {
+ packageInfo.packageName);
}
activePackagesSet.add(packageInfo.packageName);
if (mApexModuleNameToActivePackageName.containsKey(ai.moduleName)) {
throw new IllegalStateException(
"Two active packages have the same APEX module name: "
+ ai.moduleName);
}
mApexModuleNameToActivePackageName.put(
ai.moduleName, packageInfo.packageName);
}
if (ai.isFactory) {
// Don't throw when the duplicating APEX is VNDK APEX
@@ -912,6 +933,16 @@ public abstract class ApexManager {
}
}
@Override
@Nullable
public String getActivePackageNameForApexModuleName(String apexModuleName) {
synchronized (mLock) {
Preconditions.checkState(mApexModuleNameToActivePackageName != null,
"APEX packages have not been scanned");
return mApexModuleNameToActivePackageName.get(apexModuleName);
}
}
@Override
public boolean snapshotCeData(int userId, int rollbackId, String apexPackageName) {
String apexModuleName;
@@ -1329,6 +1360,12 @@ public abstract class ApexManager {
return null;
}
@Override
@Nullable
public String getActivePackageNameForApexModuleName(String apexModuleName) {
return null;
}
@Override
public boolean snapshotCeData(int userId, int rollbackId, String apexPackageName) {
throw new UnsupportedOperationException();

View File

@@ -489,6 +489,20 @@ public class ApexManagerTest {
assertThat(e).hasMessageThat().contains("Failed to collect certificates from ");
}
@Test
public void testGetActivePackageNameForApexModuleName() throws Exception {
final String moduleName = "com.android.module_name";
ApexInfo[] apexInfo = createApexInfoForTestPkg(true, false);
apexInfo[0].moduleName = moduleName;
when(mApexService.getAllPackages()).thenReturn(apexInfo);
mApexManager.scanApexPackagesTraced(mPackageParser2,
ParallelPackageParser.makeExecutorService());
assertThat(mApexManager.getActivePackageNameForApexModuleName(moduleName))
.isEqualTo(TEST_APEX_PKG);
}
private ApexInfo[] createApexInfoForTestPkg(boolean isActive, boolean isFactory) {
File apexFile = extractResource(TEST_APEX_PKG, TEST_APEX_FILE_NAME);
ApexInfo apexInfo = new ApexInfo();