Merge pull request #11155 from eric-wieser/datetime-stack-overflow

BUG: Prevent stackoverflow in conversion to datetime types

4 files changed, 41 insertions, 21 deletions

diff --git a/numpy/core/include/numpy/npy_3kcompat.h b/numpy/core/include/numpy/npy_3kcompat.h
index 56fbd99af..2d0ccd3b9 100644
--- a/numpy/core/include/numpy/npy_3kcompat.h
+++ b/numpy/core/include/numpy/npy_3kcompat.h
@@ -61,6 +61,14 @@ static NPY_INLINE int PyInt_Check(PyObject *op) {
     PySlice_GetIndicesEx((PySliceObject *)op, nop, start, end, step, slicelength)
 #endif
 
+/* <2.7.11 and <3.4.4 have the wrong argument type for Py_EnterRecursiveCall */
+#if (PY_VERSION_HEX < 0x02070B00) || \
+    ((0x03000000 <= PY_VERSION_HEX) && (PY_VERSION_HEX < 0x03040400))
+    #define Npy_EnterRecursiveCall(x) Py_EnterRecursiveCall((char *)(x))
+#else
+    #define Npy_EnterRecursiveCall(x) Py_EnterRecursiveCall(x)
+#endif
+
 /*
  * PyString -> PyBytes
  */
diff --git a/numpy/core/src/multiarray/datetime.c b/numpy/core/src/multiarray/datetime.c
index af542aecc..df9b9cec4 100644
--- a/numpy/core/src/multiarray/datetime.c
+++ b/numpy/core/src/multiarray/datetime.c
@@ -3721,19 +3721,21 @@ recursive_find_object_datetime64_type(PyObject *obj,
         }
 
         for (i = 0; i < len; ++i) {
+            int ret;
             PyObject *f = PySequence_GetItem(obj, i);
             if (f == NULL) {
                 return -1;
             }
-            if (f == obj) {
-                Py_DECREF(f);
-                return 0;
-            }
-            if (recursive_find_object_datetime64_type(f, meta) < 0) {
+            if (Npy_EnterRecursiveCall(" in recursive_find_object_datetime64_type") != 0) {
                 Py_DECREF(f);
                 return -1;
             }
+            ret = recursive_find_object_datetime64_type(f, meta);
+            Py_LeaveRecursiveCall();
             Py_DECREF(f);
+            if (ret < 0) {
+                return ret;
+            }
         }
 
         return 0;
@@ -3823,19 +3825,21 @@ recursive_find_object_timedelta64_type(PyObject *obj,
         }
 
         for (i = 0; i < len; ++i) {
+            int ret;
             PyObject *f = PySequence_GetItem(obj, i);
             if (f == NULL) {
                 return -1;
             }
-            if (f == obj) {
-                Py_DECREF(f);
-                return 0;
-            }
-            if (recursive_find_object_timedelta64_type(f, meta) < 0) {
+            if (Npy_EnterRecursiveCall(" in recursive_find_object_timedelta64_type") != 0) {
                 Py_DECREF(f);
                 return -1;
             }
+            ret = recursive_find_object_timedelta64_type(f, meta);
+            Py_LeaveRecursiveCall();
             Py_DECREF(f);
+            if (ret < 0) {
+                return ret;
+            }
         }
 
         return 0;
diff --git a/numpy/core/src/multiarray/number.c b/numpy/core/src/multiarray/number.c
index 14389a925..448d2d9c2 100644
--- a/numpy/core/src/multiarray/number.c
+++ b/numpy/core/src/multiarray/number.c
@@ -16,15 +16,6 @@
 
 #include "binop_override.h"
 
-/* <2.7.11 and <3.4.4 have the wrong argument type for Py_EnterRecursiveCall */
-#if (PY_VERSION_HEX < 0x02070B00) || \
-    ((0x03000000 <= PY_VERSION_HEX) && (PY_VERSION_HEX < 0x03040400))
-    #define _Py_EnterRecursiveCall(x) Py_EnterRecursiveCall((char *)(x))
-#else
-    #define _Py_EnterRecursiveCall(x) Py_EnterRecursiveCall(x)
-#endif
-
-
 /*************************************************************************
  ****************   Implement Number Protocol ****************************
  *************************************************************************/
@@ -796,7 +787,7 @@ _array_nonzero(PyArrayObject *mp)
     n = PyArray_SIZE(mp);
     if (n == 1) {
         int res;
-        if (_Py_EnterRecursiveCall(" while converting array to bool")) {
+        if (Npy_EnterRecursiveCall(" while converting array to bool")) {
             return -1;
         }
         res = PyArray_DESCR(mp)->f->nonzero(PyArray_DATA(mp), mp);
@@ -850,7 +841,7 @@ array_scalar_forward(PyArrayObject *v,
     /* Need to guard against recursion if our array holds references */
     if (PyDataType_REFCHK(PyArray_DESCR(v))) {
         PyObject *res;
-        if (_Py_EnterRecursiveCall(where) != 0) {
+        if (Npy_EnterRecursiveCall(where) != 0) {
             Py_DECREF(scalar);
             return NULL;
         }
diff --git a/numpy/core/tests/test_datetime.py b/numpy/core/tests/test_datetime.py
index e433877e8..942554cae 100644
--- a/numpy/core/tests/test_datetime.py
+++ b/numpy/core/tests/test_datetime.py
@@ -17,6 +17,11 @@ try:
 except ImportError:
     _has_pytz = False
 
+try:
+    RecursionError
+except NameError:
+    RecursionError = RuntimeError  # python < 3.5
+
 
 class TestDateTime(object):
     def test_datetime_dtype_creation(self):
@@ -1997,6 +2002,18 @@ class TestDateTime(object):
                 continue
             assert_raises(TypeError, np.isnat, np.zeros(10, t))
 
+    def test_corecursive_input(self):
+        # construct a co-recursive list
+        a, b = [], []
+        a.append(b)
+        b.append(a)
+        obj_arr = np.array([None])
+        obj_arr[0] = a
+
+        # gh-11154: This shouldn't cause a C stack overflow
+        assert_raises(RecursionError, obj_arr.astype, 'M8')
+        assert_raises(RecursionError, obj_arr.astype, 'm8')
+
 
 class TestDateTimeData(object):