2 files changed, 6 insertions, 0 deletions
diff --git a/dexlayout/compact_dex_writer.h b/dexlayout/compact_dex_writer.h
index 4834bfc3af..24d0fbf61d 100644
--- a/dexlayout/compact_dex_writer.h
+++ b/dexlayout/compact_dex_writer.h
@@ -60,11 +60,14 @@ class CompactDexWriter : public DexWriter {
             return false;
           }
           const uint8_t* data = Data();
+          DCHECK_LE(a.offset_ + a.length_, section_->Size());
+          DCHECK_LE(b.offset_ + b.length_, section_->Size());
           return std::equal(data + a.offset_, data + a.offset_ + a.length_, data + b.offset_);
         }
 
         // Hash function.
         size_t operator()(const HashedMemoryRange& range) const {
+          DCHECK_LE(range.offset_ + range.length_, section_->Size());
           return HashBytes(Data() + range.offset_, range.length_);
         }
 
diff --git a/dexlayout/dex_writer.h b/dexlayout/dex_writer.h
index e6e05334e4..dd613ed688 100644
--- a/dexlayout/dex_writer.h
+++ b/dexlayout/dex_writer.h
@@ -85,6 +85,7 @@ class DexWriter {
 
     void Seek(size_t position) {
       position_ = position;
+      EnsureStorage(0u);
     }
 
     // Does not allow overwriting for bug prevention purposes.
@@ -129,10 +130,12 @@ class DexWriter {
 
     ALWAYS_INLINE void AlignTo(const size_t alignment) {
       position_ = RoundUp(position_, alignment);
+      EnsureStorage(0u);
     }
 
     ALWAYS_INLINE void Skip(const size_t count) {
       position_ += count;
+      EnsureStorage(0u);
     }
 
     class ScopedSeek {