(arrow) branch main updated: GH-38626: [Python] Fix segfault when PyArrow is imported at shutdown (#38637)

[jorisvandenbossche]

This is an automated email from the ASF dual-hosted git repository.

jorisvandenbossche pushed a commit to branch main
in repository https://gitbox.apache.org/repos/asf/arrow.git


The following commit(s) were added to refs/heads/main by this push:
     new f3ec224ab6 GH-38626: [Python] Fix segfault when PyArrow is imported at 
shutdown (#38637)
f3ec224ab6 is described below

commit f3ec224ab6ace14f630509c79dfbba2ec32d881a
Author: Antoine Pitrou <anto...@python.org>
AuthorDate: Tue Nov 14 14:25:29 2023 +0100

    GH-38626: [Python] Fix segfault when PyArrow is imported at shutdown 
(#38637)
    
    
    ### Rationale for this change
    
    Some C++ destructors may be called after the Python interpreter has ceased 
to exist.
    If such a destructor tries to call back in the Python interpreter, for 
example by calling `Py_DECREF`, we get a crash.
    
    ### What changes are included in this PR?
    
    Protect `OwnedRef` and `OwneRefNoGIL` destructors against decref'ing a 
Python object after Python finalization.
    
    ### Are these changes tested?
    
    Yes.
    
    ### Are there any user-facing changes?
    
    No.
    * Closes: #38626
    
    Authored-by: Antoine Pitrou <anto...@python.org>
    Signed-off-by: Joris Van den Bossche <jorisvandenboss...@gmail.com>
---
 python/pyarrow/src/arrow/python/common.h | 17 ++++++++++-------
 python/pyarrow/tests/test_misc.py        | 13 +++++++++++++
 2 files changed, 23 insertions(+), 7 deletions(-)

diff --git a/python/pyarrow/src/arrow/python/common.h 
b/python/pyarrow/src/arrow/python/common.h
index e36c0834fd..bc567ef78e 100644
--- a/python/pyarrow/src/arrow/python/common.h
+++ b/python/pyarrow/src/arrow/python/common.h
@@ -188,7 +188,12 @@ class ARROW_PYTHON_EXPORT OwnedRef {
     return *this;
   }
 
-  ~OwnedRef() { reset(); }
+  ~OwnedRef() {
+    // GH-38626: destructor may be called after the Python interpreter is 
finalized.
+    if (Py_IsInitialized()) {
+      reset();
+    }
+  }
 
   void reset(PyObject* obj) {
     Py_XDECREF(obj_);
@@ -225,13 +230,11 @@ class ARROW_PYTHON_EXPORT OwnedRefNoGIL : public OwnedRef 
{
   explicit OwnedRefNoGIL(PyObject* obj) : OwnedRef(obj) {}
 
   ~OwnedRefNoGIL() {
-    // This destructor may be called after the Python interpreter is finalized.
-    // At least avoid spurious attempts to take the GIL when not necessary.
-    if (obj() == NULLPTR) {
-      return;
+    // GH-38626: destructor may be called after the Python interpreter is 
finalized.
+    if (Py_IsInitialized() && obj() != NULLPTR) {
+      PyAcquireGIL lock;
+      reset();
     }
-    PyAcquireGIL lock;
-    reset();
   }
 };
 
diff --git a/python/pyarrow/tests/test_misc.py 
b/python/pyarrow/tests/test_misc.py
index 9b9dfdd554..a48ac0c3cd 100644
--- a/python/pyarrow/tests/test_misc.py
+++ b/python/pyarrow/tests/test_misc.py
@@ -117,6 +117,19 @@ def test_runtime_info():
         subprocess.check_call([sys.executable, "-c", code], env=env)
 
 
+def test_import_at_shutdown():
+    # GH-38626: importing PyArrow at interpreter shutdown would crash
+    code = """if 1:
+        import atexit
+
+        def import_arrow():
+            import pyarrow
+
+        atexit.register(import_arrow)
+        """
+    subprocess.check_call([sys.executable, "-c", code])
+
+
 @pytest.mark.skipif(sys.platform == "win32",
                     reason="Path to timezone database is not configurable "
                            "on non-Windows platforms")