commit d23f9500efa59d46c57db423a630b111e889a680
author Jooyung Han <jooyung@google.com> Thu Dec 23 14:39:57 2021 +0900
committer Jooyung Han <jooyung@google.com> Fri Dec 24 08:54:31 2021 +0900
tree ca24b8b72a0b211dbca226a18693ea93b26952e0
parent a98ef807a612f81cf75dd4c83ba09e00d2df6ebf

libbinder: added enforceNoDataAvail()

enforceNoDataAvail() verifies that there's no bytes left to be read on
the Parcel.

Bug: 208509444
Test: atest binderUnitTest
Test: binder_parcel_fuzzer
Change-Id: I469c8778fa54f3db27f00a9df8db668a0c4c76bc

libs/binder/tests/binderParcelUnitTest.cpp

diff --git a/libs/binder/tests/binderParcelUnitTest.cpp b/libs/binder/tests/binderParcelUnitTest.cpp
index 4950b23..aee15d8 100644
--- a/libs/binder/tests/binderParcelUnitTest.cpp
+++ b/libs/binder/tests/binderParcelUnitTest.cpp
@@ -16,15 +16,17 @@
 
 #include <binder/IPCThreadState.h>
 #include <binder/Parcel.h>
+#include <binder/Status.h>
 #include <cutils/ashmem.h>
 #include <gtest/gtest.h>
 
 using android::IPCThreadState;
 using android::OK;
 using android::Parcel;
+using android::status_t;
 using android::String16;
 using android::String8;
-using android::status_t;
+using android::binder::Status;
 
 TEST(Parcel, NonNullTerminatedString8) {
     String8 kTestString = String8("test-is-good");
@@ -60,6 +62,19 @@
     EXPECT_EQ(output.size(), 0);
 }
 
+TEST(Parcel, EnforceNoDataAvail) {
+    const int32_t kTestInt = 42;
+    const String8 kTestString = String8("test-is-good");
+    Parcel p;
+    p.writeInt32(kTestInt);
+    p.writeString8(kTestString);
+    p.setDataPosition(0);
+    EXPECT_EQ(kTestInt, p.readInt32());
+    EXPECT_EQ(p.enforceNoDataAvail().exceptionCode(), Status::Exception::EX_BAD_PARCELABLE);
+    EXPECT_EQ(kTestString, p.readString8());
+    EXPECT_EQ(p.enforceNoDataAvail().exceptionCode(), Status::Exception::EX_NONE);
+}
+
 // Tests a second operation results in a parcel at the same location as it
 // started.
 void parcelOpSameLength(const std::function<void(Parcel*)>& a, const std::function<void(Parcel*)>& b) {

libs/binder/tests/parcel_fuzzer/binder.cpp

diff --git a/libs/binder/tests/parcel_fuzzer/binder.cpp b/libs/binder/tests/parcel_fuzzer/binder.cpp
index 077d915..13f7195 100644
--- a/libs/binder/tests/parcel_fuzzer/binder.cpp
+++ b/libs/binder/tests/parcel_fuzzer/binder.cpp
@@ -22,6 +22,7 @@
 #include <android/os/IServiceManager.h>
 #include <binder/ParcelableHolder.h>
 #include <binder/PersistableBundle.h>
+#include <binder/Status.h>
 
 using ::android::status_t;
 using ::android::base::HexString;
@@ -100,6 +101,7 @@
     PARCEL_READ_NO_STATUS(size_t, dataAvail),
     PARCEL_READ_NO_STATUS(size_t, dataPosition),
     PARCEL_READ_NO_STATUS(size_t, dataCapacity),
+    PARCEL_READ_NO_STATUS(::android::binder::Status, enforceNoDataAvail),
     [] (const ::android::Parcel& p, uint8_t pos) {
         FUZZ_LOG() << "about to setDataPosition: " << pos;
         p.setDataPosition(pos);