Merge "Add the protection to avoid data overflow in BinaryXmlSerializer.java"...

Merge "Add the protection to avoid data overflow in BinaryXmlSerializer.java" into sc-dev am: 039660c4 am: 20643002

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/27416928



Change-Id: I333b2db1faa1eb093ec010cf1a72f97730cd97d5
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>

core/java/com/android/internal/util/BinaryXmlSerializer.java

@@ -97,6 +97,8 @@ public final class BinaryXmlSerializer implements TypedXmlSerializer {
      */
     private static final int BUFFER_SIZE = 32_768;
 
+    private static final int MAX_UNSIGNED_SHORT = 65_535;
+
     private FastDataOutput mOut;
 
     /**
@@ -221,6 +223,10 @@ public final class BinaryXmlSerializer implements TypedXmlSerializer {
         if (namespace != null && !namespace.isEmpty()) throw illegalNamespace();
         mOut.writeByte(ATTRIBUTE | TYPE_BYTES_HEX);
         mOut.writeInternedUTF(name);
+        if (value.length > MAX_UNSIGNED_SHORT) {
+            throw new IOException("attributeBytesHex: input size (" + value.length
+                    + ") exceeds maximum allowed size (" + MAX_UNSIGNED_SHORT + ")");
+        }
         mOut.writeShort(value.length);
         mOut.write(value);
         return this;
@@ -232,6 +238,10 @@ public final class BinaryXmlSerializer implements TypedXmlSerializer {
         if (namespace != null && !namespace.isEmpty()) throw illegalNamespace();
         mOut.writeByte(ATTRIBUTE | TYPE_BYTES_BASE64);
         mOut.writeInternedUTF(name);
+        if (value.length > MAX_UNSIGNED_SHORT) {
+            throw new IOException("attributeBytesBase64: input size (" + value.length
+                    + ") exceeds maximum allowed size (" + MAX_UNSIGNED_SHORT + ")");
+        }
         mOut.writeShort(value.length);
         mOut.write(value);
         return this;

core/tests/coretests/src/android/util/BinaryXmlTest.java

@@ -24,6 +24,8 @@ import static android.util.XmlTest.doVerifyRead;
 import static android.util.XmlTest.doVerifyWrite;
 
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertThrows;
+import static org.junit.Assert.fail;
 import static org.xmlpull.v1.XmlPullParser.START_TAG;
 
 import android.os.PersistableBundle;
@@ -38,12 +40,15 @@ import java.io.ByteArrayOutputStream;
 import java.io.File;
 import java.io.FileInputStream;
 import java.io.FileOutputStream;
+import java.io.IOException;
 import java.io.InputStream;
 import java.io.OutputStream;
 import java.nio.charset.StandardCharsets;
 
 @RunWith(AndroidJUnit4.class)
 public class BinaryXmlTest {
+    private static final int MAX_UNSIGNED_SHORT = 65_535;
+
     /**
      * Verify that we can write and read large numbers of interned
      * {@link String} values.
@@ -167,4 +172,49 @@ public class BinaryXmlTest {
             }
         }
     }
+
+    @Test
+    public void testAttributeBytes_BinaryDataOverflow() throws Exception {
+        final TypedXmlSerializer out = Xml.newBinarySerializer();
+        final ByteArrayOutputStream os = new ByteArrayOutputStream();
+        out.setOutput(os, StandardCharsets.UTF_8.name());
+
+        final byte[] testBytes = new byte[MAX_UNSIGNED_SHORT + 1];
+        assertThrows(IOException.class,
+                () -> out.attributeBytesHex(/* namespace */ null, /* name */ "attributeBytesHex",
+                        testBytes));
+
+        assertThrows(IOException.class,
+                () -> out.attributeBytesBase64(/* namespace */ null, /* name */
+                        "attributeBytesBase64", testBytes));
+    }
+
+    @Test
+    public void testAttributeBytesHex_MaximumBinaryData() throws Exception {
+        final TypedXmlSerializer out = Xml.newBinarySerializer();
+        final ByteArrayOutputStream os = new ByteArrayOutputStream();
+        out.setOutput(os, StandardCharsets.UTF_8.name());
+
+        final byte[] testBytes = new byte[MAX_UNSIGNED_SHORT];
+        try {
+            out.attributeBytesHex(/* namespace */ null, /* name */ "attributeBytesHex", testBytes);
+        } catch (Exception e) {
+            fail("testAttributeBytesHex fails with exception: " + e.toString());
+        }
+    }
+
+    @Test
+    public void testAttributeBytesBase64_MaximumBinaryData() throws Exception {
+        final TypedXmlSerializer out = Xml.newBinarySerializer();
+        final ByteArrayOutputStream os = new ByteArrayOutputStream();
+        out.setOutput(os, StandardCharsets.UTF_8.name());
+
+        final byte[] testBytes = new byte[MAX_UNSIGNED_SHORT];
+        try {
+            out.attributeBytesBase64(/* namespace */ null, /* name */ "attributeBytesBase64",
+                    testBytes);
+        } catch (Exception e) {
+            fail("testAttributeBytesBase64 fails with exception: " + e.toString());
+        }
+    }
 }