Fix ProtoId ordering check in DexFileVerifier.
The code previously checked for kNoDexIndex16 as the type
list terminator. This is incorrect as we should not actually
see the kNoDexIndex16 in type lists in supported dex files.
To make sure that we don't see kNoDexIndex16, check the size
of the arrays with documented limits, i.e. type-ids and
proto-ids, see dex_file.h. In the ProtoId ordering check,
DCHECK() that we don't encounter kNoDexIndex16 and verify
that the previous list is not longer if the current list's
elements match.
Bug: 28580925
Change-Id: I7b17ce54b0047d97e13be88377676b1b7c713ae1
diff --git a/runtime/dex_file_verifier.cc b/runtime/dex_file_verifier.cc
index 21ee4bd..bafa057 100644
--- a/runtime/dex_file_verifier.cc
+++ b/runtime/dex_file_verifier.cc
@@ -251,6 +251,14 @@
return true;
}
+bool DexFileVerifier::CheckSizeLimit(uint32_t size, uint32_t limit, const char* label) {
+ if (size > limit) {
+ ErrorStringPrintf("Size(%u) should not exceed limit(%u) for %s.", size, limit, label);
+ return false;
+ }
+ return true;
+}
+
bool DexFileVerifier::CheckHeader() {
// Check file size from the header.
uint32_t expected_size = header_->file_size_;
@@ -298,10 +306,12 @@
header_->type_ids_size_,
4,
"type-ids") &&
+ CheckSizeLimit(header_->type_ids_size_, DexFile::kDexNoIndex16, "type-ids") &&
CheckValidOffsetAndSize(header_->proto_ids_off_,
header_->proto_ids_size_,
4,
"proto-ids") &&
+ CheckSizeLimit(header_->proto_ids_size_, DexFile::kDexNoIndex16, "proto-ids") &&
CheckValidOffsetAndSize(header_->field_ids_off_,
header_->field_ids_size_,
4,
@@ -1786,13 +1796,8 @@
while (curr_it.HasNext() && prev_it.HasNext()) {
uint16_t prev_idx = prev_it.GetTypeIdx();
uint16_t curr_idx = curr_it.GetTypeIdx();
- if (prev_idx == DexFile::kDexNoIndex16) {
- break;
- }
- if (UNLIKELY(curr_idx == DexFile::kDexNoIndex16)) {
- ErrorStringPrintf("Out-of-order proto_id arguments");
- return false;
- }
+ DCHECK_NE(prev_idx, DexFile::kDexNoIndex16);
+ DCHECK_NE(curr_idx, DexFile::kDexNoIndex16);
if (prev_idx < curr_idx) {
break;
@@ -1804,6 +1809,12 @@
prev_it.Next();
curr_it.Next();
}
+ if (!curr_it.HasNext()) {
+ // Either a duplicate ProtoId or a ProtoId with a shorter argument list follows
+ // a ProtoId with a longer one. Both cases are forbidden by the specification.
+ ErrorStringPrintf("Out-of-order proto_id arguments");
+ return false;
+ }
}
}