From a35481823dc73a1e8ef2af87f60f541a8e46c4c4 Mon Sep 17 00:00:00 2001 From: Zackery Spytz Date: Thu, 9 Jul 2020 04:00:21 -0600 Subject: [PATCH] bpo-41252: Fix incorrect refcounting in _ssl.c's _servername_callback() (GH-21407) (cherry picked from commit ee96f32ca24779656d3c8736d26671fc3689f0a3) Co-authored-by: Zackery Spytz --- .../Core and Builtins/2020-07-08-21-55-23.bpo-41252.nBWL-Y.rst | 1 + Modules/_ssl.c | 3 ++- 2 files changed, 3 insertions(+), 1 deletion(-) create mode 100644 Misc/NEWS.d/next/Core and Builtins/2020-07-08-21-55-23.bpo-41252.nBWL-Y.rst diff --git a/Misc/NEWS.d/next/Core and Builtins/2020-07-08-21-55-23.bpo-41252.nBWL-Y.rst b/Misc/NEWS.d/next/Core and Builtins/2020-07-08-21-55-23.bpo-41252.nBWL-Y.rst new file mode 100644 index 00000000000000..65f3189c83ec64 --- /dev/null +++ b/Misc/NEWS.d/next/Core and Builtins/2020-07-08-21-55-23.bpo-41252.nBWL-Y.rst @@ -0,0 +1 @@ +Fix incorrect refcounting in _ssl.c's ``_servername_callback()``. diff --git a/Modules/_ssl.c b/Modules/_ssl.c index 58064178a1a343..a8c339d9f33344 100644 --- a/Modules/_ssl.c +++ b/Modules/_ssl.c @@ -4545,11 +4545,12 @@ _servername_callback(SSL *s, int *al, void *args) * back into a str object, but still as an A-label (bpo-28414) */ servername_str = PyUnicode_FromEncodedObject(servername_bytes, "ascii", NULL); - Py_DECREF(servername_bytes); if (servername_str == NULL) { PyErr_WriteUnraisable(servername_bytes); + Py_DECREF(servername_bytes); goto error; } + Py_DECREF(servername_bytes); result = PyObject_CallFunctionObjArgs( ssl_ctx->set_sni_cb, ssl_socket, servername_str, ssl_ctx, NULL);