Merge changes from topic "presubmit-am-596ac78c570647d8a0f30d123eb656a7" into sc-qpr1-dev

* changes:
  [automerge] Ensure policy has no absurdly long strings 2p: 12c201509e
  Ensure policy has no absurdly long strings

2 files changed, 92 insertions, 4 deletions

diff --git a/core/java/android/app/admin/DevicePolicyManager.java b/core/java/android/app/admin/DevicePolicyManager.java
index aea502828c36..efa08c8cae3b 100644
--- a/core/java/android/app/admin/DevicePolicyManager.java
+++ b/core/java/android/app/admin/DevicePolicyManager.java
@@ -11283,7 +11283,8 @@ public class DevicePolicyManager {
 
     /**
      * Called by a device admin to set the long support message. This will be displayed to the user
-     * in the device administators settings screen.
+     * in the device administrators settings screen. If the message is longer than 20000 characters
+     * it may be truncated.
      * <p>
      * If the long support message needs to be localized, it is the responsibility of the
      * {@link DeviceAdminReceiver} to listen to the {@link Intent#ACTION_LOCALE_CHANGED} broadcast
diff --git a/services/devicepolicy/java/com/android/server/devicepolicy/DevicePolicyManagerService.java b/services/devicepolicy/java/com/android/server/devicepolicy/DevicePolicyManagerService.java
index acdf2d0ab3ea..903df2d6efee 100644
--- a/services/devicepolicy/java/com/android/server/devicepolicy/DevicePolicyManagerService.java
+++ b/services/devicepolicy/java/com/android/server/devicepolicy/DevicePolicyManagerService.java
@@ -360,6 +360,7 @@ import java.security.cert.CertificateFactory;
 import java.security.cert.X509Certificate;
 import java.text.DateFormat;
 import java.time.LocalDate;
+import java.util.ArrayDeque;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
@@ -371,6 +372,7 @@ import java.util.List;
 import java.util.Locale;
 import java.util.Map;
 import java.util.Objects;
+import java.util.Queue;
 import java.util.Set;
 import java.util.concurrent.TimeUnit;
 import java.util.function.Function;
@@ -399,6 +401,15 @@ public class DevicePolicyManagerService extends BaseIDevicePolicyManager {
 
     private static final int REQUEST_PROFILE_OFF_DEADLINE = 5572;
 
+    // Binary XML serializer doesn't support longer strings
+    private static final int MAX_POLICY_STRING_LENGTH = 65535;
+    // FrameworkParsingPackageUtils#MAX_FILE_NAME_SIZE, Android packages are used in dir names.
+    private static final int MAX_PACKAGE_NAME_LENGTH = 223;
+
+    private static final int MAX_LONG_SUPPORT_MESSAGE_LENGTH = 20000;
+    private static final int MAX_SHORT_SUPPORT_MESSAGE_LENGTH = 200;
+    private static final int MAX_ORG_NAME_LENGTH = 200;
+
     private static final long MS_PER_DAY = TimeUnit.DAYS.toMillis(1);
 
     private static final long EXPIRATION_GRACE_PERIOD_MS = 5 * MS_PER_DAY; // 5 days, in ms
@@ -9869,6 +9880,12 @@ public class DevicePolicyManagerService extends BaseIDevicePolicyManager {
         }
         Objects.requireNonNull(admin, "admin is null");
         Objects.requireNonNull(agent, "agent is null");
+        enforceMaxPackageNameLength(agent.getPackageName());
+        final String agentAsString = agent.flattenToString();
+        enforceMaxStringLength(agentAsString, "agent name");
+        if (args != null) {
+            enforceMaxStringLength(args, "args");
+        }
         final int userHandle = UserHandle.getCallingUserId();
         synchronized (getLockObject()) {
             ActiveAdmin ap = getActiveAdminForCallerLocked(admin,
@@ -10107,6 +10124,10 @@ public class DevicePolicyManagerService extends BaseIDevicePolicyManager {
         final CallerIdentity caller = getCallerIdentity(who);
 
         if (packageList != null) {
+            for (String pkg : (List<String>) packageList) {
+                enforceMaxPackageNameLength(pkg);
+            }
+
             int userId = caller.getUserId();
             final List<AccessibilityServiceInfo> enabledServices;
             long id = mInjector.binderClearCallingIdentity();
@@ -10273,6 +10294,10 @@ public class DevicePolicyManagerService extends BaseIDevicePolicyManager {
         }
 
         if (packageList != null) {
+            for (String pkg : (List<String>) packageList) {
+                enforceMaxPackageNameLength(pkg);
+            }
+
             List<InputMethodInfo> enabledImes = mInjector.binderWithCleanCallingIdentity(() ->
                     InputMethodManagerInternal.get().getEnabledInputMethodListAsUser(userId));
             if (enabledImes != null) {
@@ -11497,6 +11522,8 @@ public class DevicePolicyManagerService extends BaseIDevicePolicyManager {
             return;
         }
         Objects.requireNonNull(who, "ComponentName is null");
+        enforceMaxStringLength(accountType, "account type");
+
         final CallerIdentity caller = getCallerIdentity(who);
         synchronized (getLockObject()) {
             /*
@@ -11915,6 +11942,10 @@ public class DevicePolicyManagerService extends BaseIDevicePolicyManager {
             throws SecurityException {
         Objects.requireNonNull(who, "ComponentName is null");
         Objects.requireNonNull(packages, "packages is null");
+        for (String pkg : packages) {
+            enforceMaxPackageNameLength(pkg);
+        }
+
         final CallerIdentity caller = getCallerIdentity(who);
 
         synchronized (getLockObject()) {
@@ -13924,6 +13955,8 @@ public class DevicePolicyManagerService extends BaseIDevicePolicyManager {
             return;
         }
         Objects.requireNonNull(who, "ComponentName is null");
+        message = truncateIfLonger(message, MAX_SHORT_SUPPORT_MESSAGE_LENGTH);
+
         final CallerIdentity caller = getCallerIdentity(who);
         synchronized (getLockObject()) {
             ActiveAdmin admin = getActiveAdminForUidLocked(who, caller.getUid());
@@ -13956,6 +13989,9 @@ public class DevicePolicyManagerService extends BaseIDevicePolicyManager {
         if (!mHasFeature) {
             return;
         }
+
+        message = truncateIfLonger(message, MAX_LONG_SUPPORT_MESSAGE_LENGTH);
+
         Objects.requireNonNull(who, "ComponentName is null");
         final CallerIdentity caller = getCallerIdentity(who);
         synchronized (getLockObject()) {
@@ -14105,6 +14141,8 @@ public class DevicePolicyManagerService extends BaseIDevicePolicyManager {
         Objects.requireNonNull(who, "ComponentName is null");
         final CallerIdentity caller = getCallerIdentity(who);
 
+        text = truncateIfLonger(text, MAX_ORG_NAME_LENGTH);
+
         synchronized (getLockObject()) {
             ActiveAdmin admin = getProfileOwnerOrDeviceOwnerLocked(caller);
             if (!TextUtils.equals(admin.organizationName, text)) {
@@ -14354,9 +14392,8 @@ public class DevicePolicyManagerService extends BaseIDevicePolicyManager {
             throw new IllegalArgumentException("ids must not be null");
         }
         for (String id : ids) {
-            if (TextUtils.isEmpty(id)) {
-                throw new IllegalArgumentException("ids must not contain empty string");
-            }
+            Preconditions.checkArgument(!TextUtils.isEmpty(id), "ids must not have empty string");
+            enforceMaxStringLength(id, "affiliation id");
         }
 
         final Set<String> affiliationIds = new ArraySet<>(ids);
@@ -15613,6 +15650,9 @@ public class DevicePolicyManagerService extends BaseIDevicePolicyManager {
                 "Provided administrator and target are the same object.");
         Preconditions.checkArgument(!admin.getPackageName().equals(target.getPackageName()),
                 "Provided administrator and target have the same package name.");
+        if (bundle != null) {
+            enforceMaxStringLength(bundle, "bundle");
+        }
 
         final CallerIdentity caller = getCallerIdentity(admin);
         Preconditions.checkCallAuthorization(isDeviceOwner(caller) || isProfileOwner(caller));
@@ -17697,4 +17737,51 @@ public class DevicePolicyManagerService extends BaseIDevicePolicyManager {
                         && mInjector.getUsbManager().getUsbHalVersion() >= UsbManager.USB_HAL_V1_3
         );
     }
+
+    /**
+     * Truncates char sequence to maximum length, nulls are ignored.
+     */
+    private static CharSequence truncateIfLonger(CharSequence input, int maxLength) {
+        return input == null || input.length() <= maxLength
+                ? input
+                : input.subSequence(0, maxLength);
+    }
+
+    /**
+     * Throw if string argument is too long to be serialized.
+     */
+    private static void enforceMaxStringLength(String str, String argName) {
+        Preconditions.checkArgument(
+                str.length() <= MAX_POLICY_STRING_LENGTH, argName + " loo long");
+    }
+
+    private static void enforceMaxPackageNameLength(String pkg) {
+        Preconditions.checkArgument(
+                pkg.length() <= MAX_PACKAGE_NAME_LENGTH, "Package name too long");
+    }
+
+    /**
+     * Throw if persistable bundle contains any string that we can't serialize.
+     */
+    private static void enforceMaxStringLength(PersistableBundle bundle, String argName) {
+        // Persistable bundles can have other persistable bundles as values, traverse with a queue.
+        Queue<PersistableBundle> queue = new ArrayDeque<>();
+        queue.add(bundle);
+        while (!queue.isEmpty()) {
+            PersistableBundle current = queue.remove();
+            for (String key : current.keySet()) {
+                enforceMaxStringLength(key, "key in " + argName);
+                Object value = current.get(key);
+                if (value instanceof String) {
+                    enforceMaxStringLength((String) value, "string value in " + argName);
+                } else if (value instanceof String[]) {
+                    for (String str : (String[]) value) {
+                        enforceMaxStringLength(str, "string value in " + argName);
+                    }
+                } else if (value instanceof PersistableBundle) {
+                    queue.add((PersistableBundle) value);
+                }
+            }
+        }
+    }
 }