commit 5ed5a4d0ed57299f7e7caf5a05c95c67e6719ed1
author Michael Wachenschwanz <mwachens@google.com> Tue Apr 17 16:52:40 2018 -0700
committer android-build-team Robot <android-build-team-robot@google.com> Fri Jul 20 00:18:29 2018 +0000
tree e7ca1da7bc4cdb7a7533f5b4a8273e07714c00db
parent 267f287c76953affe9a749677161d164ef53d79e

Increment when attempting to read protected Parcel Data

Make sure to increment the parcel data position even when trying to
improperly read from protected data

Bug: 29833520

Test (M): cts-tradefed run cts -c android.os.cts.ParcelTest -m testBinderDataProtection
Test (M): cts-tradefed run cts -c android.os.cts.ParcelTest -m testBinderDataProtectionIncrements
Test: cts-tradefed run cts -m CtsOsTestCases -t android.os.cts.ParcelTest#testBinderDataProtection
Test: cts-tradefed run cts -m CtsOsTestCases -t android.os.cts.ParcelTest#testBinderDataProtectionIncrements

Change-Id: Ie4aae6277fc5f5c924f603d9828c3a608998b986
Merged-In: Ie4aae6277fc5f5c924f603d9828c3a608998b986
(cherry picked from commit 6a825e8ad1a3928dd872bb7c3fbcd94784d77267)

libs/binder/Parcel.cpp

diff --git a/libs/binder/Parcel.cpp b/libs/binder/Parcel.cpp
index 44357c3..3fafbb8 100644
--- a/libs/binder/Parcel.cpp
+++ b/libs/binder/Parcel.cpp
@@ -1535,7 +1535,12 @@
             && len <= pad_size(len)) {
         if (mObjectsSize > 0) {
             status_t err = validateReadData(mDataPos + pad_size(len));
-            if(err != NO_ERROR) return err;
+            if(err != NO_ERROR) {
+                // Still increment the data position by the expected length
+                mDataPos += pad_size(len);
+                ALOGV("read Setting data pos of %p to %zu", this, mDataPos);
+                return err;
+            }
         }
         memcpy(outData, mData+mDataPos, len);
         mDataPos += pad_size(len);
@@ -1557,7 +1562,12 @@
             && len <= pad_size(len)) {
         if (mObjectsSize > 0) {
             status_t err = validateReadData(mDataPos + pad_size(len));
-            if(err != NO_ERROR) return NULL;
+            if(err != NO_ERROR) {
+                // Still increment the data position by the expected length
+                mDataPos += pad_size(len);
+                ALOGV("readInplace Setting data pos of %p to %zu", this, mDataPos);
+                return NULL;
+            }
         }
 
         const void* data = mData+mDataPos;
@@ -1575,7 +1585,11 @@
     if ((mDataPos+sizeof(T)) <= mDataSize) {
         if (mObjectsSize > 0) {
             status_t err = validateReadData(mDataPos + sizeof(T));
-            if(err != NO_ERROR) return err;
+            if(err != NO_ERROR) {
+                // Still increment the data position by the expected length
+                mDataPos += sizeof(T);
+                return err;
+            }
         }
 
         const void* data = mData+mDataPos;