8216426: Usage of array placement new may lead to memory corruption
Reviewed-by: rehn, kbarrett, rkennke, eosterlund
diff --git a/src/hotspot/share/utilities/concurrentHashTable.hpp b/src/hotspot/share/utilities/concurrentHashTable.hpp
index f4e47ca..b5a9c9e 100644
--- a/src/hotspot/share/utilities/concurrentHashTable.hpp
+++ b/src/hotspot/share/utilities/concurrentHashTable.hpp
@@ -68,7 +68,7 @@
void print_value_on(outputStream* st) const {};
};
- // Only constructed with placement new[] from an array allocated with MEMFLAGS
+ // Only constructed with placement new from an array allocated with MEMFLAGS
// of InternalTable.
class Bucket {
private:
diff --git a/src/hotspot/share/utilities/concurrentHashTable.inline.hpp b/src/hotspot/share/utilities/concurrentHashTable.inline.hpp
index 720097a..72d16a3 100644
--- a/src/hotspot/share/utilities/concurrentHashTable.inline.hpp
+++ b/src/hotspot/share/utilities/concurrentHashTable.inline.hpp
@@ -193,8 +193,12 @@
{
assert(_log2_size >= SIZE_SMALL_LOG2 && _log2_size <= SIZE_BIG_LOG2,
"Bad size");
- void* memory = NEW_C_HEAP_ARRAY(Bucket, _size, F);
- _buckets = new (memory) Bucket[_size];
+ _buckets = NEW_C_HEAP_ARRAY(Bucket, _size, F);
+ // Use placement new for each element instead of new[] which could use more
+ // memory than allocated.
+ for (size_t i = 0; i < _size; ++i) {
+ new (_buckets + i) Bucket();
+ }
}
template <typename VALUE, typename CONFIG, MEMFLAGS F>
