From: Nathaniel J. Smith <njs@pobox.com>
Date: Thu, 8 Jun 2017 11:14:40 +0000 (-0700)
Subject: [3.6] bpo-30594: Fixed refcounting in newPySSLSocket (GH-1992) (#1994)
X-Git-Tag: v3.6.2rc1~86
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=854f7ba1d5cbb6a42511beae66c8dbe34f2cbcd3;p=python

[3.6] bpo-30594: Fixed refcounting in newPySSLSocket (GH-1992) (#1994)

If pass a server_hostname= that fails IDNA decoding to SSLContext.wrap_socket or SSLContext.wrap_bio, then the SSLContext object had a spurious Py_DECREF called on it, eventually leading to segfaults.
(cherry picked from commit 65ece7ca2366308fa91a39a8dfa255e6bdce3cca)
---

diff --git a/Modules/_ssl.c b/Modules/_ssl.c
index 2a2c18fe2f..dbfbd44399 100644
--- a/Modules/_ssl.c
+++ b/Modules/_ssl.c
@@ -599,6 +599,7 @@ newPySSLSocket(PySSLContext *sslctx, PySocketSockObject *sock,
     self->ssl = NULL;
     self->Socket = NULL;
     self->ctx = sslctx;
+    Py_INCREF(sslctx);
     self->shutdown_seen_zero = 0;
     self->handshake_done = 0;
     self->owner = NULL;
@@ -613,8 +614,6 @@ newPySSLSocket(PySSLContext *sslctx, PySocketSockObject *sock,
         self->server_hostname = hostname;
     }
 
-    Py_INCREF(sslctx);
-
     /* Make sure the SSL error state is initialized */
     (void) ERR_get_state();
     ERR_clear_error();