Check IsModifiableClass earlier in redefineClasses and retransformClasses

We were not checking this until we actually tried to install the
definition. This meant that we could send dex file data to agents even
if there is no chance of it being used. We would also try to get the
dex file name for non-existant dex files causing crashes.

Bug: 31455788
Test: ./test/testrunner/testrunner.py --host -t 921-hello-failure
Change-Id: I647a057fe916861d555ae142a2961f449f1bc3a5

5 files changed, 71 insertions, 1 deletions

diff --git a/runtime/openjdkjvmti/ti_redefine.cc b/runtime/openjdkjvmti/ti_redefine.cc
index 7a69078391..a173a4abdd 100644
--- a/runtime/openjdkjvmti/ti_redefine.cc
+++ b/runtime/openjdkjvmti/ti_redefine.cc
@@ -325,12 +325,19 @@ jvmtiError Redefiner::RedefineClasses(ArtJvmTiEnv* env,
   std::vector<ArtClassDefinition> def_vector;
   def_vector.reserve(class_count);
   for (jint i = 0; i < class_count; i++) {
+    jboolean is_modifiable = JNI_FALSE;
+    jvmtiError res = env->IsModifiableClass(definitions[i].klass, &is_modifiable);
+    if (res != OK) {
+      return res;
+    } else if (!is_modifiable) {
+      return ERR(UNMODIFIABLE_CLASS);
+    }
     // We make a copy of the class_bytes to pass into the retransformation.
     // This makes cleanup easier (since we unambiguously own the bytes) and also is useful since we
     // will need to keep the original bytes around unaltered for subsequent RetransformClasses calls
     // to get the passed in bytes.
     unsigned char* class_bytes_copy = nullptr;
-    jvmtiError res = env->Allocate(definitions[i].class_byte_count, &class_bytes_copy);
+    res = env->Allocate(definitions[i].class_byte_count, &class_bytes_copy);
     if (res != OK) {
       return res;
     }
diff --git a/runtime/openjdkjvmti/transform.cc b/runtime/openjdkjvmti/transform.cc
index 36421b9137..bd52cbb7f9 100644
--- a/runtime/openjdkjvmti/transform.cc
+++ b/runtime/openjdkjvmti/transform.cc
@@ -109,6 +109,13 @@ jvmtiError Transformer::RetransformClasses(ArtJvmTiEnv* env,
   std::vector<ArtClassDefinition> definitions;
   jvmtiError res = OK;
   for (jint i = 0; i < class_count; i++) {
+    jboolean is_modifiable = JNI_FALSE;
+    res = env->IsModifiableClass(classes[i], &is_modifiable);
+    if (res != OK) {
+      return res;
+    } else if (!is_modifiable) {
+      return ERR(UNMODIFIABLE_CLASS);
+    }
     ArtClassDefinition def;
     res = FillInTransformationData(env, classes[i], &def);
     if (res != OK) {
diff --git a/test/921-hello-failure/expected.txt b/test/921-hello-failure/expected.txt
index a5dc10d59c..fdbfbe2191 100644
--- a/test/921-hello-failure/expected.txt
+++ b/test/921-hello-failure/expected.txt
@@ -50,3 +50,6 @@ hello there - MissingField
 hello there again - FieldChange
 Transformation error : java.lang.Exception(Failed to redefine class <LTransform4;> due to JVMTI_ERROR_UNSUPPORTED_REDEFINITION_SCHEMA_CHANGED)
 hello there again - FieldChange
+hello - Unmodifiable
+Transformation error : java.lang.Exception(Failed to redefine class <[LTransform;> due to JVMTI_ERROR_UNMODIFIABLE_CLASS)
+hello - Unmodifiable
diff --git a/test/921-hello-failure/src/Main.java b/test/921-hello-failure/src/Main.java
index 5bbe2b5479..6779ed862a 100644
--- a/test/921-hello-failure/src/Main.java
+++ b/test/921-hello-failure/src/Main.java
@@ -32,6 +32,7 @@ public class Main {
     NewField.doTest(new Transform());
     MissingField.doTest(new Transform4("there"));
     FieldChange.doTest(new Transform4("there again"));
+    Unmodifiable.doTest(new Transform[] { new Transform(), });
   }
 
   // Transforms the class. This throws an exception if something goes wrong.
diff --git a/test/921-hello-failure/src/Unmodifiable.java b/test/921-hello-failure/src/Unmodifiable.java
new file mode 100644
index 0000000000..ad05f51f9f
--- /dev/null
+++ b/test/921-hello-failure/src/Unmodifiable.java
@@ -0,0 +1,52 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import java.util.Base64;
+
+class Unmodifiable {
+  // The following is a base64 encoding of a valid class file.
+  private static final byte[] CLASS_BYTES = Base64.getDecoder().decode(
+    "yv66vgAAADQAFQoABgAPBwAQCAARCgACABIHABMHABQBAAY8aW5pdD4BAAMoKVYBAARDb2RlAQAP" +
+    "TGluZU51bWJlclRhYmxlAQAFc2F5SGkBABUoTGphdmEvbGFuZy9TdHJpbmc7KVYBAApTb3VyY2VG" +
+    "aWxlAQAOVHJhbnNmb3JtLmphdmEMAAcACAEAD2phdmEvbGFuZy9FcnJvcgEAFVNob3VsZCBub3Qg" +
+    "YmUgY2FsbGVkIQwABwAMAQAJVHJhbnNmb3JtAQAQamF2YS9sYW5nL09iamVjdAAgAAUABgAAAAAA" +
+    "AgAAAAcACAABAAkAAAAdAAEAAQAAAAUqtwABsQAAAAEACgAAAAYAAQAAAAIAAAALAAwAAQAJAAAA" +
+    "IgADAAIAAAAKuwACWRIDtwAEvwAAAAEACgAAAAYAAQAAAAQAAQANAAAAAgAO");
+  private static final byte[] DEX_BYTES = Base64.getDecoder().decode(
+    "ZGV4CjAzNQCrV81cy4Q+YKMMMqc0bZEO5Y1X5u7irPeQAgAAcAAAAHhWNBIAAAAAAAAAAPwBAAAL" +
+    "AAAAcAAAAAUAAACcAAAAAgAAALAAAAAAAAAAAAAAAAQAAADIAAAAAQAAAOgAAACIAQAACAEAAEoB" +
+    "AABSAQAAXwEAAHIBAACGAQAAmgEAALEBAADBAQAAxAEAAMgBAADcAQAAAQAAAAIAAAADAAAABAAA" +
+    "AAcAAAAHAAAABAAAAAAAAAAIAAAABAAAAEQBAAAAAAAAAAAAAAAAAQAKAAAAAQABAAAAAAACAAAA" +
+    "AAAAAAAAAAAAAAAAAgAAAAAAAAAGAAAAAAAAAO4BAAAAAAAAAQABAAEAAADjAQAABAAAAHAQAwAA" +
+    "AA4ABAACAAIAAADoAQAACQAAACIAAQAbAQUAAABwIAIAEAAnAAAAAQAAAAMABjxpbml0PgALTFRy" +
+    "YW5zZm9ybTsAEUxqYXZhL2xhbmcvRXJyb3I7ABJMamF2YS9sYW5nL09iamVjdDsAEkxqYXZhL2xh" +
+    "bmcvU3RyaW5nOwAVU2hvdWxkIG5vdCBiZSBjYWxsZWQhAA5UcmFuc2Zvcm0uamF2YQABVgACVkwA" +
+    "EmVtaXR0ZXI6IGphY2stNC4yNAAFc2F5SGkAAgAHDgAEAQAHDgAAAAEBAICABIgCAQCgAgwAAAAA" +
+    "AAAAAQAAAAAAAAABAAAACwAAAHAAAAACAAAABQAAAJwAAAADAAAAAgAAALAAAAAFAAAABAAAAMgA" +
+    "AAAGAAAAAQAAAOgAAAABIAAAAgAAAAgBAAABEAAAAQAAAEQBAAACIAAACwAAAEoBAAADIAAAAgAA" +
+    "AOMBAAAAIAAAAQAAAO4BAAAAEAAAAQAAAPwBAAA=");
+
+  public static void doTest(Transform[] ts) {
+    ts[0].sayHi("Unmodifiable");
+    try {
+      Main.doCommonClassRedefinition(Transform[].class, CLASS_BYTES, DEX_BYTES);
+    } catch (Exception e) {
+      System.out.println(
+          "Transformation error : " + e.getClass().getName() + "(" + e.getMessage() + ")");
+    }
+    ts[0].sayHi("Unmodifiable");
+  }
+}