Do not throw new incremental not found exceptions

For incremental hardening, our primary focus is to ensure the system
does not crash. Rather than throw new exceptions when querying from
incrementally installed packages we should return null values and not
subvert API expectations by throwing exceptions in places that
normally cannot fail.

This may cause UI issues when an app loads the resources of a
different, incrementally installed package. We can introduce new APIs
to allow system apps to determine when a package not being fully
present would cause issues on a case-by-case basis.

We will be able to tell from logcat and bugreports where the failed
read occurred in the resources.arsc.

Bug: 169167078
Test: builds
Change-Id: Idfd9ad11b64fc9e8dce9d0fa7ab9b6e4f6083d41

core/jni/android_content_res_ApkAssets.cpp

@@ -29,7 +29,6 @@
 #include "utils/Trace.h"
 
 #include "android_content_res_ApkAssets.h"
-#include "android_util_AssetManager_private.h"
 #include "core_jni_helpers.h"
 #include "jni.h"
 #include "nativehelper/ScopedUtfChars.h"
@@ -473,8 +472,9 @@ static jlong NativeOpenXml(JNIEnv* env, jclass /*clazz*/, jlong ptr, jstring fil
   const auto buffer = asset->getIncFsBuffer(true /* aligned */);
   const size_t length = asset->getLength();
   if (!buffer.convert<uint8_t>().verify(length)) {
-    jniThrowException(env, kResourcesNotFound, kIOErrorMessage);
-    return 0;
+      jniThrowException(env, "java/io/FileNotFoundException",
+                        "File not fully present due to incremental installation");
+      return 0;
   }
 
   // DynamicRefTable is only needed when looking up resource references. Opening an XML file

core/jni/android_util_AssetManager.cpp

@@ -43,7 +43,6 @@
 #include "androidfw/ResourceUtils.h"
 
 #include "android_content_res_ApkAssets.h"
-#include "android_util_AssetManager_private.h"
 #include "core_jni_helpers.h"
 #include "jni.h"
 #include "nativehelper/JNIPlatformHelp.h"
@@ -574,8 +573,9 @@ static jlong NativeOpenXmlAsset(JNIEnv* env, jobject /*clazz*/, jlong ptr, jint
   const incfs::map_ptr<void> buffer = asset->getIncFsBuffer(true /* aligned */);
   const size_t length = asset->getLength();
   if (!buffer.convert<uint8_t>().verify(length)) {
-    jniThrowException(env, kResourcesNotFound, kIOErrorMessage);
-    return 0;
+      jniThrowException(env, "java/io/FileNotFoundException",
+                        "File not fully present due to incremental installation");
+      return 0;
   }
 
   auto xml_tree = util::make_unique<ResXMLTree>(assetmanager->GetDynamicRefTableForCookie(cookie));
@@ -611,8 +611,9 @@ static jlong NativeOpenXmlAssetFd(JNIEnv* env, jobject /*clazz*/, jlong ptr, int
   const incfs::map_ptr<void> buffer = asset->getIncFsBuffer(true /* aligned */);
   const size_t length = asset->getLength();
   if (!buffer.convert<uint8_t>().verify(length)) {
-    jniThrowException(env, kResourcesNotFound, kIOErrorMessage);
-    return 0;
+      jniThrowException(env, "java/io/FileNotFoundException",
+                        "File not fully present due to incremental installation");
+      return 0;
   }
 
   auto xml_tree = util::make_unique<ResXMLTree>(assetmanager->GetDynamicRefTableForCookie(cookie));
@@ -631,14 +632,12 @@ static jint NativeGetResourceValue(JNIEnv* env, jclass /*clazz*/, jlong ptr, jin
   auto value = assetmanager->GetResource(static_cast<uint32_t>(resid), false /*may_be_bag*/,
                                          static_cast<uint16_t>(density));
   if (!value.has_value()) {
-    ThrowIfIOError(env, value);
     return ApkAssetsCookieToJavaCookie(kInvalidCookie);
   }
 
   if (resolve_references) {
     auto result = assetmanager->ResolveReference(value.value());
     if (!result.has_value()) {
-      ThrowIfIOError(env, result);
       return ApkAssetsCookieToJavaCookie(kInvalidCookie);
     }
   }
@@ -650,7 +649,6 @@ static jint NativeGetResourceBagValue(JNIEnv* env, jclass /*clazz*/, jlong ptr,
   ScopedLock<AssetManager2> assetmanager(AssetManagerFromLong(ptr));
   auto bag = assetmanager->GetBag(static_cast<uint32_t>(resid));
   if (!bag.has_value()) {
-    ThrowIfIOError(env, bag);
     return ApkAssetsCookieToJavaCookie(kInvalidCookie);
   }
 
@@ -669,7 +667,6 @@ static jint NativeGetResourceBagValue(JNIEnv* env, jclass /*clazz*/, jlong ptr,
   AssetManager2::SelectedValue attr_value(*bag, *entry);
   auto result = assetmanager->ResolveReference(attr_value);
   if (!result.has_value()) {
-    ThrowIfIOError(env, result);
     return ApkAssetsCookieToJavaCookie(kInvalidCookie);
   }
   return CopyValue(env, attr_value, typed_value);
@@ -679,7 +676,6 @@ static jintArray NativeGetStyleAttributes(JNIEnv* env, jclass /*clazz*/, jlong p
   ScopedLock<AssetManager2> assetmanager(AssetManagerFromLong(ptr));
   auto bag_result = assetmanager->GetBag(static_cast<uint32_t>(resid));
   if (!bag_result.has_value()) {
-    ThrowIfIOError(env, bag_result);
     return nullptr;
   }
 
@@ -701,7 +697,6 @@ static jobjectArray NativeGetResourceStringArray(JNIEnv* env, jclass /*clazz*/,
   ScopedLock<AssetManager2> assetmanager(AssetManagerFromLong(ptr));
   auto bag_result = assetmanager->GetBag(static_cast<uint32_t>(resid));
   if (!bag_result.has_value()) {
-    ThrowIfIOError(env, bag_result);
     return nullptr;
   }
 
@@ -716,7 +711,6 @@ static jobjectArray NativeGetResourceStringArray(JNIEnv* env, jclass /*clazz*/,
     AssetManager2::SelectedValue attr_value(bag, bag->entries[i]);
     auto result = assetmanager->ResolveReference(attr_value);
     if (!result.has_value()) {
-      ThrowIfIOError(env, result);
       return nullptr;
     }
 
@@ -724,22 +718,16 @@ static jobjectArray NativeGetResourceStringArray(JNIEnv* env, jclass /*clazz*/,
       const ApkAssets* apk_assets = assetmanager->GetApkAssets()[attr_value.cookie];
       const ResStringPool* pool = apk_assets->GetLoadedArsc()->GetStringPool();
 
-      jstring java_string = nullptr;
-      auto str_utf8 = pool->string8At(attr_value.data);
-      if (UNLIKELY(ThrowIfIOError(env, str_utf8))) {
-        return nullptr;
-      }
-
-      if (str_utf8.has_value()) {
-        java_string = env->NewStringUTF(str_utf8->data());
+      jstring java_string;
+      if (auto str_utf8 = pool->string8At(attr_value.data); str_utf8.has_value()) {
+          java_string = env->NewStringUTF(str_utf8->data());
       } else {
-        auto str_utf16 = pool->stringAt(attr_value.data);
-        if (!str_utf16.has_value()) {
-          ThrowIfIOError(env, str_utf16);
-          return nullptr;
-        }
-        java_string = env->NewString(reinterpret_cast<const jchar*>(str_utf16->data()),
-                                     str_utf16->size());
+          auto str_utf16 = pool->stringAt(attr_value.data);
+          if (!str_utf16.has_value()) {
+              return nullptr;
+          }
+          java_string = env->NewString(reinterpret_cast<const jchar*>(str_utf16->data()),
+                                       str_utf16->size());
       }
 
       // Check for errors creating the strings (if malformed or no memory).
@@ -762,7 +750,6 @@ static jintArray NativeGetResourceStringArrayInfo(JNIEnv* env, jclass /*clazz*/,
   ScopedLock<AssetManager2> assetmanager(AssetManagerFromLong(ptr));
   auto bag_result = assetmanager->GetBag(static_cast<uint32_t>(resid));
   if (!bag_result.has_value()) {
-    ThrowIfIOError(env, bag_result);
     return nullptr;
   }
 
@@ -782,7 +769,6 @@ static jintArray NativeGetResourceStringArrayInfo(JNIEnv* env, jclass /*clazz*/,
     auto result = assetmanager->ResolveReference(attr_value);
     if (!result.has_value()) {
       env->ReleasePrimitiveArrayCritical(array, buffer, JNI_ABORT);
-      ThrowIfIOError(env, result);
       return nullptr;
     }
 
@@ -802,7 +788,6 @@ static jintArray NativeGetResourceIntArray(JNIEnv* env, jclass /*clazz*/, jlong
   ScopedLock<AssetManager2> assetmanager(AssetManagerFromLong(ptr));
   auto bag_result = assetmanager->GetBag(static_cast<uint32_t>(resid));
   if (!bag_result.has_value()) {
-    ThrowIfIOError(env, bag_result);
     return nullptr;
   }
 
@@ -822,7 +807,6 @@ static jintArray NativeGetResourceIntArray(JNIEnv* env, jclass /*clazz*/, jlong
     auto result = assetmanager->ResolveReference(attr_value);
     if (!result.has_value()) {
       env->ReleasePrimitiveArrayCritical(array, buffer, 0);
-      ThrowIfIOError(env, result);
       return nullptr;
     }
 
@@ -839,7 +823,6 @@ static jint NativeGetResourceArraySize(JNIEnv* env, jclass /*clazz*/, jlong ptr,
     ScopedLock<AssetManager2> assetmanager(AssetManagerFromLong(ptr));
     auto bag = assetmanager->GetBag(static_cast<uint32_t>(resid));
     if (!bag.has_value()) {
-      ThrowIfIOError(env, bag);
       return -1;
     }
     return static_cast<jint>((*bag)->entry_count);
@@ -850,7 +833,6 @@ static jint NativeGetResourceArray(JNIEnv* env, jclass /*clazz*/, jlong ptr, jin
   ScopedLock<AssetManager2> assetmanager(AssetManagerFromLong(ptr));
   auto bag_result = assetmanager->GetBag(static_cast<uint32_t>(resid));
   if (!bag_result.has_value()) {
-    ThrowIfIOError(env, bag_result);
     return -1;
   }
 
@@ -877,7 +859,6 @@ static jint NativeGetResourceArray(JNIEnv* env, jclass /*clazz*/, jlong ptr, jin
     auto result = assetmanager->ResolveReference(attr_value);
     if (!result.has_value()) {
       env->ReleasePrimitiveArrayCritical(out_data, buffer, JNI_ABORT);
-      ThrowIfIOError(env, bag_result);
       return -1;
     }
 
@@ -924,7 +905,6 @@ static jint NativeGetResourceIdentifier(JNIEnv* env, jclass /*clazz*/, jlong ptr
   ScopedLock<AssetManager2> assetmanager(AssetManagerFromLong(ptr));
   auto resid = assetmanager->GetResourceId(name_utf8.c_str(), type, package);
   if (!resid.has_value()) {
-    ThrowIfIOError(env, resid);
     return 0;
   }
 
@@ -935,7 +915,6 @@ static jstring NativeGetResourceName(JNIEnv* env, jclass /*clazz*/, jlong ptr, j
   ScopedLock<AssetManager2> assetmanager(AssetManagerFromLong(ptr));
   auto name = assetmanager->GetResourceName(static_cast<uint32_t>(resid));
   if (!name.has_value()) {
-    ThrowIfIOError(env, name);
     return nullptr;
   }
 
@@ -947,7 +926,6 @@ static jstring NativeGetResourcePackageName(JNIEnv* env, jclass /*clazz*/, jlong
   ScopedLock<AssetManager2> assetmanager(AssetManagerFromLong(ptr));
   auto name = assetmanager->GetResourceName(static_cast<uint32_t>(resid));
   if (!name.has_value()) {
-    ThrowIfIOError(env, name);
     return nullptr;
   }
 
@@ -961,7 +939,6 @@ static jstring NativeGetResourceTypeName(JNIEnv* env, jclass /*clazz*/, jlong pt
   ScopedLock<AssetManager2> assetmanager(AssetManagerFromLong(ptr));
   auto name = assetmanager->GetResourceName(static_cast<uint32_t>(resid));
   if (!name.has_value()) {
-    ThrowIfIOError(env, name);
     return nullptr;
   }
 
@@ -977,7 +954,6 @@ static jstring NativeGetResourceEntryName(JNIEnv* env, jclass /*clazz*/, jlong p
   ScopedLock<AssetManager2> assetmanager(AssetManagerFromLong(ptr));
   auto name = assetmanager->GetResourceName(static_cast<uint32_t>(resid));
   if (!name.has_value()) {
-    ThrowIfIOError(env, name);
     return nullptr;
   }
 
@@ -1051,7 +1027,6 @@ static jobjectArray NativeGetSizeConfigurations(JNIEnv* env, jclass /*clazz*/, j
   auto configurations = assetmanager->GetResourceConfigurations(true /*exclude_system*/,
                                                                 false /*exclude_mipmap*/);
   if (!configurations.has_value()) {
-    ThrowIfIOError(env, configurations);
     return nullptr;
   }
 
@@ -1129,11 +1104,10 @@ static void NativeApplyStyle(JNIEnv* env, jclass /*clazz*/, jlong ptr, jlong the
     return;
   }
 
-  auto result = ApplyStyle(theme, xml_parser, static_cast<uint32_t>(def_style_attr),
-                           static_cast<uint32_t>(def_style_resid),
-                           reinterpret_cast<uint32_t*>(attrs), attrs_len, out_values, out_indices);
+  ApplyStyle(theme, xml_parser, static_cast<uint32_t>(def_style_attr),
+             static_cast<uint32_t>(def_style_resid), reinterpret_cast<uint32_t*>(attrs), attrs_len,
+             out_values, out_indices);
   env->ReleasePrimitiveArrayCritical(java_attrs, attrs, JNI_ABORT);
-  ThrowIfIOError(env, result);
 }
 
 static jboolean NativeResolveAttrs(JNIEnv* env, jclass /*clazz*/, jlong ptr, jlong theme_ptr,
@@ -1210,11 +1184,7 @@ static jboolean NativeResolveAttrs(JNIEnv* env, jclass /*clazz*/, jlong ptr, jlo
   }
 
   env->ReleasePrimitiveArrayCritical(java_attrs, attrs, JNI_ABORT);
-  if (!result.has_value()) {
-    ThrowIfIOError(env, result);
-    return JNI_FALSE;
-  }
-  return JNI_TRUE;
+  return result.has_value() ? JNI_TRUE : JNI_FALSE;
 }
 
 static jboolean NativeRetrieveAttributes(JNIEnv* env, jclass /*clazz*/, jlong ptr,
@@ -1266,11 +1236,7 @@ static jboolean NativeRetrieveAttributes(JNIEnv* env, jclass /*clazz*/, jlong pt
 
   env->ReleasePrimitiveArrayCritical(out_java_values, out_values, 0);
   env->ReleasePrimitiveArrayCritical(java_attrs, attrs, JNI_ABORT);
-  if (!result.has_value()) {
-    ThrowIfIOError(env, result);
-    return JNI_FALSE;
-  }
-  return JNI_TRUE;
+  return result.has_value() ? JNI_TRUE : JNI_FALSE;
 }
 
 static jlong NativeThemeCreate(JNIEnv* /*env*/, jclass /*clazz*/, jlong ptr) {
@@ -1290,8 +1256,7 @@ static void NativeThemeApplyStyle(JNIEnv* env, jclass /*clazz*/, jlong ptr, jlon
   CHECK(theme->GetAssetManager() == &(*assetmanager));
   (void) assetmanager;
 
-  auto result = theme->ApplyStyle(static_cast<uint32_t>(resid), force);
-  ThrowIfIOError(env, result);
+  theme->ApplyStyle(static_cast<uint32_t>(resid), force);
 
   // TODO(adamlesinski): Consider surfacing exception when result is failure.
   // CTS currently expects no exceptions from this method.
@@ -1313,13 +1278,10 @@ static void NativeThemeCopy(JNIEnv* env, jclass /*clazz*/, jlong dst_asset_manag
     CHECK(dst_theme->GetAssetManager() == &(*dst_assetmanager));
     (void) dst_assetmanager;
 
-    auto result = dst_theme->SetTo(*src_theme);
-    ThrowIfIOError(env, result);
-    return;
+    dst_theme->SetTo(*src_theme);
+  } else {
+      dst_theme->SetTo(*src_theme);
   }
-
-  auto result = dst_theme->SetTo(*src_theme);
-  ThrowIfIOError(env, result);
 }
 
 static void NativeThemeClear(JNIEnv* /*env*/, jclass /*clazz*/, jlong theme_ptr) {
@@ -1345,7 +1307,6 @@ static jint NativeThemeGetAttributeValue(JNIEnv* env, jclass /*clazz*/, jlong pt
 
   auto result = theme->GetAssetManager()->ResolveReference(*value);
   if (!result.has_value()) {
-    ThrowIfIOError(env, result);
     return ApkAssetsCookieToJavaCookie(kInvalidCookie);
   }
   return CopyValue(env, *value, typed_value);

core/jni/android_util_AssetManager_private.h

@@ -1,54 +0,0 @@
-/*
- * Copyright (C) 2008 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.
- */
-
-#ifndef ANDROID_UTIL_ASSETMANAGER_PRIVATE_H
-#define ANDROID_UTIL_ASSETMANAGER_PRIVATE_H
-
-#include <optional>
-
-#include <androidfw/Errors.h>
-#include <android-base/expected.h>
-
-#include "core_jni_helpers.h"
-#include "jni.h"
-#include "nativehelper/JNIHelp.h"
-
-namespace android {
-
-constexpr const char* kResourcesNotFound = "android/content/res/Resources$NotFoundException";
-constexpr const static char* kIOErrorMessage = "failed to read resources.arsc data";
-
-template <typename T, typename E>
-static bool ThrowIfIOError(JNIEnv* env, const base::expected<T, E>& result) {
-  if constexpr (std::is_same<NullOrIOError, E>::value) {
-    if (IsIOError(result)) {
-      jniThrowException(env, kResourcesNotFound, kIOErrorMessage);
-      return true;
-    }
-     return false;
-  } else {
-    if (!result.has_value()) {
-      static_assert(std::is_same<IOError, E>::value, "Unknown result error type");
-      jniThrowException(env, kResourcesNotFound, kIOErrorMessage);
-      return true;
-    }
-    return false;
-  }
-}
-
-} // namespace android
-
-#endif //ANDROID_UTIL_ASSETMANAGER_PRIVATE_H

core/jni/android_util_StringBlock.cpp

@@ -17,7 +17,6 @@
 
 #define LOG_TAG "StringBlock"
 
-#include "android_util_AssetManager_private.h"
 #include "jni.h"
 #include <nativehelper/JNIHelp.h>
 #include <utils/misc.h>
@@ -76,17 +75,12 @@ static jstring android_content_StringBlock_nativeGetString(JNIEnv* env, jobject
         return 0;
     }
 
-    auto str8 = osb->string8At(idx);
-    if (UNLIKELY(ThrowIfIOError(env, str8))) {
-        return 0;
-    } else if (str8.has_value()) {
+    if (auto str8 = osb->string8At(idx); str8.has_value()) {
         return env->NewStringUTF(str8->data());
     }
 
     auto str = osb->stringAt(idx);
-    if (UNLIKELY(ThrowIfIOError(env, str))) {
-        return 0;
-    } else if (UNLIKELY(!str.has_value())) {
+    if (UNLIKELY(!str.has_value())) {
         jniThrowException(env, "java/lang/IndexOutOfBoundsException", NULL);
         return 0;
     }
@@ -104,7 +98,6 @@ static jintArray android_content_StringBlock_nativeGetStyle(JNIEnv* env, jobject
 
     auto spans = osb->styleAt(idx);
     if (!spans.has_value()) {
-        ThrowIfIOError(env, spans);
         return NULL;
     }
 
@@ -114,7 +107,6 @@ static jintArray android_content_StringBlock_nativeGetStyle(JNIEnv* env, jobject
         auto pos = *spans;
         while (true) {
             if (UNLIKELY(!pos)) {
-                jniThrowException(env, kResourcesNotFound, kIOErrorMessage);
                 return NULL;
             }
             if (pos->name.index == ResStringPool_span::END) {