1 files changed, 11 insertions, 0 deletions
diff --git a/Lib/test/test_memoryview.py b/Lib/test/test_memoryview.py
index 61e60fb..525ddea 100644
--- a/Lib/test/test_memoryview.py
+++ b/Lib/test/test_memoryview.py
@@ -9,6 +9,7 @@ import gc
 import weakref
 import array
 from test import test_support
+import io
 
 
 class AbstractMemoryTests:
@@ -230,6 +231,16 @@ class AbstractMemoryTests:
             gc.collect()
             self.assertTrue(wr() is None, wr())
 
+    def test_writable_readonly(self):
+        # Issue #10451: memoryview incorrectly exposes a readonly
+        # buffer as writable causing a segfault if using mmap
+        tp = self.ro_type
+        if tp is None:
+            return
+        b = tp(self._source)
+        m = self._view(b)
+        i = io.BytesIO(b'ZZZZ')
+        self.assertRaises(TypeError, i.readinto, m)
 
 # Variations on source objects for the buffer: bytes-like objects, then arrays
 # with itemsize > 1.