From 2a01f356861e3ffcd8eb9aac248caec4ea7204d0 Mon Sep 17 00:00:00 2001
From: Victor Stinner <vstinner@python.org>
Date: Thu, 9 Oct 2025 01:00:12 +0200
Subject: [PATCH] gh-139748: Fix socket.if_nametoindex() Argument Clinic

Fix a reference leak.
---
 Modules/clinic/socketmodule.c.h | 7 +++++--
 Modules/socketmodule.c          | 4 ++--
 2 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/Modules/clinic/socketmodule.c.h b/Modules/clinic/socketmodule.c.h
index 3f4056efff2fec..4db27a441f85a6 100644
--- a/Modules/clinic/socketmodule.c.h
+++ b/Modules/clinic/socketmodule.c.h
@@ -239,7 +239,7 @@ static PyObject *
 _socket_socket_if_nametoindex(PySocketSockObject *self, PyObject *arg)
 {
     PyObject *return_value = NULL;
-    PyObject *oname;
+    PyObject *oname = NULL;
 
     if (!PyUnicode_FSConverter(arg, &oname)) {
         goto exit;
@@ -247,6 +247,9 @@ _socket_socket_if_nametoindex(PySocketSockObject *self, PyObject *arg)
     return_value = _socket_socket_if_nametoindex_impl(self, oname);
 
 exit:
+    /* Cleanup for oname */
+    Py_XDECREF(oname);
+
     return return_value;
 }
 
@@ -259,4 +262,4 @@ _socket_socket_if_nametoindex(PySocketSockObject *self, PyObject *arg)
 #ifndef _SOCKET_SOCKET_IF_NAMETOINDEX_METHODDEF
     #define _SOCKET_SOCKET_IF_NAMETOINDEX_METHODDEF
 #endif /* !defined(_SOCKET_SOCKET_IF_NAMETOINDEX_METHODDEF) */
-/*[clinic end generated code: output=eb37b5d88a1e4661 input=a9049054013a1b77]*/
+/*[clinic end generated code: output=2a58294cf2c87e33 input=a9049054013a1b77]*/
diff --git a/Modules/socketmodule.c b/Modules/socketmodule.c
index a6910df6fba64e..af7f81701b01aa 100644
--- a/Modules/socketmodule.c
+++ b/Modules/socketmodule.c
@@ -7098,7 +7098,7 @@ Returns a list of network interface information (index, name) tuples.");
 
 /*[clinic input]
 _socket.socket.if_nametoindex
-    oname: object(converter="PyUnicode_FSConverter")
+    oname: unicode_fs_encoded
     /
 
 Returns the interface index corresponding to the interface name if_name.
@@ -7106,7 +7106,7 @@ Returns the interface index corresponding to the interface name if_name.
 
 static PyObject *
 _socket_socket_if_nametoindex_impl(PySocketSockObject *self, PyObject *oname)
-/*[clinic end generated code: output=f7fc00511a309a8e input=662688054482cd46]*/
+/*[clinic end generated code: output=f7fc00511a309a8e input=242c01253c533053]*/
 {
 #ifdef MS_WINDOWS
     NET_IFINDEX index;