heap corruption when using pin_ptr to copy from native code to managed code - c++-cli

Question

I am trying to copy unsigned short from native code to managed code, but I get a heap corruption when calling memcpy.
INPUT: unsigned short* input
OUTPUT: array<unsigned short> output
I have the following code and if I set testDataSize is 100 then I don't see corruption.
Could someone please shed some light ?
Thanks,
typedef unsigned short uns16;
// DLL Entry Point
void main()
{
int testDataSize = 600;
int frSize = testDataSize / 2;
for (int j = 0; j < 1; j++)
{
uns16* input;
array<uns16>^ output1;
array<uns16>^ output2;
input = new uns16(frSize);
output1 = gcnew array <uns16>(frSize);
output2 = gcnew array <uns16>(frSize);
// initialize
for (int i = 0; i < frSize; i++)
{
input[i] = i;
}
//test 1
Stopwatch^ sw1 = Stopwatch::StartNew();
//-------------------------------------------------------------------
array<short>^ frameDataSigned = gcnew array<short>(frSize);
Marshal::Copy(IntPtr((void*)(input)), frameDataSigned, 0, frameDataSigned->Length);
System::Buffer::BlockCopy(frameDataSigned, 0, output1, 0, (Int32)(frSize) * 2);
//-------------------------------------------------------------------
auto res1 = sw1->ElapsedTicks;
//test 2
Stopwatch^ sw2 = Stopwatch::StartNew();
//-------------------------------------------------------------------
cli::pin_ptr<uns16> pinnedManagedData = &output2[0];
memcpy(pinnedManagedData, (void*)(input), frSize * sizeof(uns16));
//-------------------------------------------------------------------
auto res2 = sw2->ElapsedTicks;
....

Answer 1

int frSize = 300;
input = new uns16(frSize);
This doesn't allocate an array. It allocates a single uint16_t, and sets its value to 300. You need to use square brackets to allocate an array.
input = new uns16[frSize];