s4-param: Check type when converting python object to lp_ctx, fix some

memory leaks.

2 files changed, 30 insertions, 3 deletions

diff --git a/source4/param/provision.c b/source4/param/provision.c
index b0387869b5..593f9ff168 100644
--- a/source4/param/provision.c
+++ b/source4/param/provision.c
@@ -85,7 +85,7 @@ NTSTATUS provision_bare(TALLOC_CTX *mem_ctx, struct loadparm_context *lp_ctx,
 			struct provision_result *result)
 {
 	const char *configfile;
-	PyObject *provision_mod, *provision_dict, *provision_fn, *py_result, *parameters;
+	PyObject *provision_mod, *provision_dict, *provision_fn, *py_result, *parameters, *py_lp_ctx;
 	
 	DEBUG(0,("Provision for Become-DC test using python\n"));
 
@@ -193,7 +193,12 @@ NTSTATUS provision_bare(TALLOC_CTX *mem_ctx, struct loadparm_context *lp_ctx,
 	result->domaindn = talloc_strdup(mem_ctx, PyString_AsString(PyObject_GetAttrString(py_result, "domaindn")));
 
 	/* FIXME paths */
-	result->lp_ctx = lpcfg_from_py_object(result, PyObject_GetAttrString(py_result, "lp"));
+	py_lp_ctx = PyObject_GetAttrString(py_result, "lp");
+	if (py_lp_ctx == NULL) {
+		DEBUG(0, ("Missing 'lp' attribute"));
+		return NT_STATUS_UNSUCCESSFUL;
+	}
+	result->lp_ctx = lpcfg_from_py_object(result, py_lp_ctx);
 	result->samdb = PyLdb_AsLdbContext(PyObject_GetAttrString(py_result, "samdb"));
 
 	return NT_STATUS_OK;
diff --git a/source4/param/pyparam_util.c b/source4/param/pyparam_util.c
index 8c98cbcbfe..474dd31504 100644
--- a/source4/param/pyparam_util.c
+++ b/source4/param/pyparam_util.c
@@ -28,6 +28,9 @@
 _PUBLIC_ struct loadparm_context *lpcfg_from_py_object(TALLOC_CTX *mem_ctx, PyObject *py_obj)
 {
     struct loadparm_context *lp_ctx;
+	PyObject *param_mod;
+	PyTypeObject *lp_type;
+	bool is_lpobj;
 
     if (PyString_Check(py_obj)) {
         lp_ctx = loadparm_init(mem_ctx);
@@ -47,7 +50,26 @@ _PUBLIC_ struct loadparm_context *lpcfg_from_py_object(TALLOC_CTX *mem_ctx, PyOb
         return lp_ctx;
     }
 
-    return PyLoadparmContext_AsLoadparmContext(py_obj);
+	param_mod = PyImport_ImportModule("samba.param");
+	if (param_mod == NULL) {
+		return NULL;
+	}
+
+	lp_type = (PyTypeObject *)PyObject_GetAttrString(param_mod, "LoadParm");
+	Py_DECREF(param_mod);
+	if (lp_type == NULL) {
+		PyErr_SetString(PyExc_RuntimeError, "Unable to import LoadParm");
+		return NULL;
+	}
+
+	is_lpobj = PyObject_TypeCheck(py_obj, lp_type);
+	Py_DECREF(lp_type);
+	if (is_lpobj) {
+		return talloc_reference(mem_ctx, PyLoadparmContext_AsLoadparmContext(py_obj));
+	}
+
+	PyErr_SetNone(PyExc_TypeError);
+	return NULL;
 }
 
 struct loadparm_context *py_default_loadparm_context(TALLOC_CTX *mem_ctx)