Fix reading of headers when using a streamable memory object.

Fixes bug where we computed the length of fields buffer on the size of a pointer, rather then the actual length of the field.

BUG= https://code.google.com/p/nativeclient/issues/detail?id=3485
R=dschuff@chromium.org

Review URL: https://codereview.chromium.org/17003002

1 files changed, 6 insertions, 4 deletions

diff --git a/lib/Bitcode/NaCl/Reader/NaClBitcodeHeader.cpp b/lib/Bitcode/NaCl/Reader/NaClBitcodeHeader.cpp
index 5193417619..aa73b9cffa 100644
--- a/lib/Bitcode/NaCl/Reader/NaClBitcodeHeader.cpp
+++ b/lib/Bitcode/NaCl/Reader/NaClBitcodeHeader.cpp
@@ -187,7 +187,7 @@ bool NaClBitcodeHeader::Read(const unsigned char *&BufPtr,
   return false;
 }
 
-bool NaClBitcodeHeader::Read(StreamingMemoryObject *Bytes) {
+bool NaClBitcodeHeader::Read(StreamableMemoryObject *Bytes) {
   unsigned NumFields;
   unsigned NumBytes;
   {
@@ -197,12 +197,14 @@ bool NaClBitcodeHeader::Read(StreamingMemoryObject *Bytes) {
       return true;
   }
   uint8_t *Header = new uint8_t[NumBytes];
-  bool results =
+  bool failed =
       Bytes->readBytes(2 * WordSize, NumBytes, Header, NULL) ||
-      ReadFields(Header, Header + sizeof(Header), NumFields, NumBytes);
+      ReadFields(Header, Header + NumBytes, NumFields, NumBytes);
   delete[] Header;
+  if (failed)
+    return true;
   InstallFields();
-  return results;
+  return false;
 }
 
 NaClBitcodeHeaderField *