commit a574b0e4772e57134538c3c098d7538d957edc90
author Jeff Hao <jeffhao@google.com> Thu Jun 04 18:12:26 2015 -0700
committer Jeff Hao <jeffhao@google.com> Tue Jun 09 11:37:41 2015 -0700
tree 03c1db0cdb463e28e3336cb14f517c3c547d8b30
parent 26b97f87dcd86934f8b75e018c80bb4e8d501b03

Make dex file verifier check for dups between direct and virtual methods.

The dex file verifier now rejects classes that have the same method index
in both direct and virtual methods.

Bug: 17878919
Change-Id: I431b4715e39ca2cce4df3ebef020b7ec0661a4c0

runtime/dex_file_verifier.cc

diff --git a/runtime/dex_file_verifier.cc b/runtime/dex_file_verifier.cc
index a66c38e..5fa58f7 100644
--- a/runtime/dex_file_verifier.cc
+++ b/runtime/dex_file_verifier.cc
@@ -465,7 +465,9 @@
 }
 
 bool DexFileVerifier::CheckClassDataItemMethod(uint32_t idx, uint32_t access_flags,
-                                               uint32_t code_offset, bool expect_direct) {
+                                               uint32_t code_offset,
+                                               std::unordered_set<uint32_t>& direct_method_indexes,
+                                               bool expect_direct) {
   if (!CheckIndex(idx, header_->method_ids_size_, "class_data_item method_idx")) {
     return false;
   }
@@ -480,6 +482,13 @@
     return false;
   }
 
+  if (expect_direct) {
+    direct_method_indexes.insert(idx);
+  } else if (direct_method_indexes.find(idx) != direct_method_indexes.end()) {
+    ErrorStringPrintf("Found virtual method with same index as direct method: %d", idx);
+    return false;
+  }
+
   constexpr uint32_t access_method_mask = kAccJavaFlagsMask | kAccConstructor |
       kAccDeclaredSynchronized;
   if (UNLIKELY(((access_flags & ~access_method_mask) != 0) ||
@@ -682,6 +691,7 @@
 
 bool DexFileVerifier::CheckIntraClassDataItem() {
   ClassDataItemIterator it(*dex_file_, ptr_);
+  std::unordered_set<uint32_t> direct_method_indexes;
 
   // These calls use the raw access flags to check whether the whole dex field is valid.
 
@@ -697,13 +707,13 @@
   }
   for (; it.HasNextDirectMethod(); it.Next()) {
     if (!CheckClassDataItemMethod(it.GetMemberIndex(), it.GetRawMemberAccessFlags(),
-        it.GetMethodCodeItemOffset(), true)) {
+        it.GetMethodCodeItemOffset(), direct_method_indexes, true)) {
       return false;
     }
   }
   for (; it.HasNextVirtualMethod(); it.Next()) {
     if (!CheckClassDataItemMethod(it.GetMemberIndex(), it.GetRawMemberAccessFlags(),
-        it.GetMethodCodeItemOffset(), false)) {
+        it.GetMethodCodeItemOffset(), direct_method_indexes, false)) {
       return false;
     }
   }

runtime/dex_file_verifier.h

diff --git a/runtime/dex_file_verifier.h b/runtime/dex_file_verifier.h
index 877dfc2..ccc40d4 100644
--- a/runtime/dex_file_verifier.h
+++ b/runtime/dex_file_verifier.h
@@ -59,6 +59,7 @@
                                  uint32_t* handler_offsets, uint32_t handlers_size);
   bool CheckClassDataItemField(uint32_t idx, uint32_t access_flags, bool expect_static);
   bool CheckClassDataItemMethod(uint32_t idx, uint32_t access_flags, uint32_t code_offset,
+                                std::unordered_set<uint32_t>& direct_method_indexes,
                                 bool expect_direct);
   bool CheckPadding(size_t offset, uint32_t aligned_offset);
   bool CheckEncodedValue();