pyldb: Prevent segfault when first module is NULL

Signed-off-by: Petr Viktorin <pviktori@redhat.com>
Reviewed-by: Andrew Bartlett <abartlet@samba.org>
Reviewed-by: Stefan Metzmacher <metze@samba.org>

2 files changed, 14 insertions, 1 deletions

diff --git a/lib/ldb/pyldb.c b/lib/ldb/pyldb.c
index ba7186036f7..efb95f50343 100644
--- a/lib/ldb/pyldb.c
+++ b/lib/ldb/pyldb.c
@@ -2045,7 +2045,11 @@ static PyObject *PyLdbModule_FromModule(struct ldb_module *mod)
 
 static PyObject *py_ldb_get_firstmodule(PyLdbObject *self, void *closure)
 {
-	return PyLdbModule_FromModule(pyldb_Ldb_AsLdbContext(self)->modules);
+	struct ldb_module *mod = pyldb_Ldb_AsLdbContext(self)->modules;
+	if (mod == NULL) {
+		Py_RETURN_NONE;
+	}
+	return PyLdbModule_FromModule(mod);
 }
 
 static PyGetSetDef py_ldb_getset[] = {
diff --git a/lib/ldb/tests/python/api.py b/lib/ldb/tests/python/api.py
index 2d9537fc2eb..a46c1ae1bff 100755
--- a/lib/ldb/tests/python/api.py
+++ b/lib/ldb/tests/python/api.py
@@ -70,6 +70,15 @@ class SimpleLdb(TestCase):
         x = ldb.Ldb(filename())
         self.assertEqual("[<ldb module 'tdb'>]", repr(x.modules()))
 
+    def test_firstmodule_none(self):
+        x = ldb.Ldb()
+        self.assertEqual(x.firstmodule, None)
+
+    def test_firstmodule_tdb(self):
+        x = ldb.Ldb(filename())
+        mod = x.firstmodule
+        self.assertEqual(repr(mod), "<ldb module 'tdb'>")
+
     def test_search(self):
         l = ldb.Ldb(filename())
         self.assertEqual(len(l.search()), 0)