[pypy-commit] cffi default: Test and fix: a negative size was implicitly converted to a huge size_t

[arigo]

Author: Armin Rigo <arigo at tunes.org>
Branch: 
Changeset: r2333:2a9a1726dae3
Date: 2015-10-09 09:58 +0200
http://bitbucket.org/cffi/cffi/changeset/2a9a1726dae3/

Log:	Test and fix: a negative size was implicitly converted to a huge
	size_t number

diff --git a/c/_cffi_backend.c b/c/_cffi_backend.c
--- a/c/_cffi_backend.c
+++ b/c/_cffi_backend.c
@@ -5822,6 +5822,10 @@
     if (!PyArg_ParseTupleAndKeywords(args, kwds, "OOn", keywords,
                                      &dest_obj, &src_obj, &n))
         return NULL;
+    if (n < 0) {
+        PyErr_SetString(PyExc_ValueError, "negative size");
+        return NULL;
+    }
 
     if (_fetch_as_buffer(src_obj, &src_view, 0) < 0) {
         return NULL;
diff --git a/c/test_c.py b/c/test_c.py
--- a/c/test_c.py
+++ b/c/test_c.py
@@ -3450,7 +3450,6 @@
     assert b.tolist() == [-997, -996, 995]
 
 def test_memmove_readonly_readwrite():
-    ffi = FFI()
     SignedChar = new_primitive_type("signed char")
     SignedCharA = new_array_type(new_pointer_type(SignedChar), None)
     p = newp(SignedCharA, 5)
@@ -3463,6 +3462,12 @@
     memmove(dest=ba, src=p, n=3)
     assert ba == bytearray(b"ABcxx")
 
+def test_memmove_sign_check():
+    SignedChar = new_primitive_type("signed char")
+    SignedCharA = new_array_type(new_pointer_type(SignedChar), None)
+    p = newp(SignedCharA, 5)
+    py.test.raises(ValueError, memmove, p, p + 1, -1)   # not segfault
+
 def test_dereference_null_ptr():
     BInt = new_primitive_type("int")
     BIntPtr = new_pointer_type(BInt)