GH-103092: isolate _ssl (#104725)

Author: kumaraditya303

Modules/_ssl.c

@@ -6150,6 +6150,18 @@ sslmodule_init_strings(PyObject *module)
     return 0;
 }
 
+static int
+sslmodule_init_lock(PyObject *module)
+{
+    _sslmodulestate *state = get_ssl_state(module);
+    state->keylog_lock = PyThread_allocate_lock();
+    if (state->keylog_lock == NULL) {
+        PyErr_NoMemory();
+        return -1;
+    }
+    return 0;
+}
+
 static PyModuleDef_Slot sslmodule_slots[] = {
     {Py_mod_exec, sslmodule_init_types},
     {Py_mod_exec, sslmodule_init_exceptions},
@@ -6158,9 +6170,8 @@ static PyModuleDef_Slot sslmodule_slots[] = {
     {Py_mod_exec, sslmodule_init_constants},
     {Py_mod_exec, sslmodule_init_versioninfo},
     {Py_mod_exec, sslmodule_init_strings},
-    // XXX gh-103092: fix isolation.
-    {Py_mod_multiple_interpreters, Py_MOD_MULTIPLE_INTERPRETERS_NOT_SUPPORTED},
-    //{Py_mod_multiple_interpreters, Py_MOD_PER_INTERPRETER_GIL_SUPPORTED},
+    {Py_mod_exec, sslmodule_init_lock},
+    {Py_mod_multiple_interpreters, Py_MOD_PER_INTERPRETER_GIL_SUPPORTED},
     {0, NULL}
 };
 
@@ -6219,6 +6230,8 @@ static void
 sslmodule_free(void *m)
 {
     sslmodule_clear((PyObject *)m);
+    _sslmodulestate *state = get_ssl_state(m);
+    PyThread_free_lock(state->keylog_lock);
 }
 
 static struct PyModuleDef _sslmodule_def = {

Modules/_ssl.h

@@ -33,6 +33,8 @@ typedef struct {
     PyObject *str_reason;
     PyObject *str_verify_code;
     PyObject *str_verify_message;
+    /* keylog lock */
+    PyThread_type_lock keylog_lock;
 } _sslmodulestate;
 
 static struct PyModuleDef _sslmodule_def;

Modules/_ssl/debughelpers.c

@@ -118,30 +118,22 @@ _PySSL_keylog_callback(const SSL *ssl, const char *line)
     PyGILState_STATE threadstate;
     PySSLSocket *ssl_obj = NULL;  /* ssl._SSLSocket, borrowed ref */
     int res, e;
-    static PyThread_type_lock *lock = NULL;
 
     threadstate = PyGILState_Ensure();
 
     ssl_obj = (PySSLSocket *)SSL_get_app_data(ssl);
     assert(Py_IS_TYPE(ssl_obj, get_state_sock(ssl_obj)->PySSLSocket_Type));
+    PyThread_type_lock lock = get_state_sock(ssl_obj)->keylog_lock;
+    assert(lock != NULL);
     if (ssl_obj->ctx->keylog_bio == NULL) {
         return;
     }
-
-    /* Allocate a static lock to synchronize writes to keylog file.
+    /*
      * The lock is neither released on exit nor on fork(). The lock is
      * also shared between all SSLContexts although contexts may write to
      * their own files. IMHO that's good enough for a non-performance
      * critical debug helper.
      */
-    if (lock == NULL) {
-        lock = PyThread_allocate_lock();
-        if (lock == NULL) {
-            PyErr_SetString(PyExc_MemoryError, "Unable to allocate lock");
-            ssl_obj->exc = PyErr_GetRaisedException();
-            return;
-        }
-    }
 
     PySSL_BEGIN_ALLOW_THREADS
     PyThread_acquire_lock(lock, 1);