diff --git a/Lib/test/test_bytes.py b/Lib/test/test_bytes.py
index 5bda9354d25..230dbf46bed 100644
--- a/Lib/test/test_bytes.py
+++ b/Lib/test/test_bytes.py
@@ -453,6 +453,11 @@ class BaseBytesTest(unittest.TestCase):
 class BytesTest(BaseBytesTest):
     type2test = bytes
 
+    def test_buffer_is_readonly(self):
+        with open(sys.stdin.fileno(), "rb", buffering=0) as f:
+            self.assertRaises(TypeError, f.readinto, b"")
+
+
 class ByteArrayTest(BaseBytesTest):
     type2test = bytearray
 
diff --git a/Lib/test/test_socket.py b/Lib/test/test_socket.py
index 222c42ce7f4..9d753b7ea53 100644
--- a/Lib/test/test_socket.py
+++ b/Lib/test/test_socket.py
@@ -1112,7 +1112,7 @@ class BufferIOTest(SocketConnectedTest):
         SocketConnectedTest.__init__(self, methodName=methodName)
 
     def testRecvInto(self):
-        buf = b" "*1024
+        buf = bytearray(1024)
         nbytes = self.cli_conn.recv_into(buf)
         self.assertEqual(nbytes, len(MSG))
         msg = buf[:len(MSG)]
@@ -1123,7 +1123,7 @@ class BufferIOTest(SocketConnectedTest):
         self.serv_conn.send(buf)
 
     def testRecvFromInto(self):
-        buf = b" "*1024
+        buf = bytearray(1024)
         nbytes, addr = self.cli_conn.recvfrom_into(buf)
         self.assertEqual(nbytes, len(MSG))
         msg = buf[:len(MSG)]
diff --git a/Objects/bytesobject.c b/Objects/bytesobject.c
index 471d09c7ec5..eeae0ff5893 100644
--- a/Objects/bytesobject.c
+++ b/Objects/bytesobject.c
@@ -965,7 +965,7 @@ static int
 string_buffer_getbuffer(PyBytesObject *self, Py_buffer *view, int flags)
 {
 	return PyBuffer_FillInfo(view, (void *)self->ob_sval, Py_SIZE(self),
-				 0, flags);
+				 1, flags);
 }
 
 static PySequenceMethods string_as_sequence = {
diff --git a/Objects/memoryobject.c b/Objects/memoryobject.c
index 78ada17aa4b..79d7db1b022 100644
--- a/Objects/memoryobject.c
+++ b/Objects/memoryobject.c
@@ -56,7 +56,7 @@ PyMemoryView_FromObject(PyObject *base)
         if (mview == NULL) return NULL;
 
         mview->base = NULL;
-        if (PyObject_GetBuffer(base, &(mview->view), PyBUF_FULL) < 0) {
+        if (PyObject_GetBuffer(base, &(mview->view), PyBUF_FULL_RO) < 0) {
                 Py_DECREF(mview);
                 return NULL;
         }
@@ -204,9 +204,9 @@ _indirect_copy_nd(char *dest, Py_buffer *view, char fort)
                 a contiguous buffer if it is not. The view will point to
                 the shadow buffer which can be written to and then
                 will be copied back into the other buffer when the memory
-                view is de-allocated.  While the shadow buffer is 
-		being used, it will have an exclusive write lock on 
-		the original buffer. 
+                view is de-allocated.  While the shadow buffer is
+		being used, it will have an exclusive write lock on
+		the original buffer.
  */
 
 PyObject *
@@ -528,7 +528,7 @@ memory_subscript(PyMemoryViewObject *self, PyObject *key)
 			/* Return a new memory-view object */
 			Py_buffer newview;
 			memset(&newview, 0, sizeof(newview));
-			/* XXX:  This needs to be fixed so it 
+			/* XXX:  This needs to be fixed so it
 			         actually returns a sub-view
 			*/
 			return PyMemoryView_FromMemory(&newview);