Fixed overflow opening a lobject with an oid not fitting in a signed int

Fixes 🎫`203`.

NEWS

@@ -10,6 +10,8 @@ What's new in psycopg 2.5.3
   Adam Petrovich for the bug report and diagnosis.
 - Fixed handling of dsn and closed attributes in connection subclasses
   failing to connect (from :ticket:`#192` discussion).
+- Fixed overflow opening a lobject with an oid not fitting in a signed int
+  (:ticket:`203`).
 - Don't segfault using poorly defined cursor subclasses which forgot to call
   the superclass init (:ticket:`#195`).
 - Fixed debug build on Windows, thanks to James Emerton.

psycopg/connection_type.c

@@ -748,7 +748,7 @@ psyco_conn_get_parameter_status(connectionObject *self, PyObject *args)
 static PyObject *
 psyco_conn_lobject(connectionObject *self, PyObject *args, PyObject *keywds)
 {
-    int oid = (int)InvalidOid, new_oid = (int)InvalidOid;
+    Oid oid = InvalidOid, new_oid = InvalidOid;
     const char *new_file = NULL;
     const char *smode = "";
     PyObject *factory = (PyObject *)&lobjectType;
@@ -757,7 +757,7 @@ psyco_conn_lobject(connectionObject *self, PyObject *args, PyObject *keywds)
     static char *kwlist[] = {"oid", "mode", "new_oid", "new_file",
                              "cursor_factory", NULL};
 
-    if (!PyArg_ParseTupleAndKeywords(args, keywds, "|izizO", kwlist,
+    if (!PyArg_ParseTupleAndKeywords(args, keywds, "|IzIzO", kwlist,
                                      &oid, &smode, &new_oid, &new_file,
                                      &factory)) {
         return NULL;
@@ -769,16 +769,16 @@ psyco_conn_lobject(connectionObject *self, PyObject *args, PyObject *keywds)
     EXC_IF_TPC_PREPARED(self, lobject);
 
     Dprintf("psyco_conn_lobject: new lobject for connection at %p", self);
-    Dprintf("psyco_conn_lobject:     parameters: oid = %d, mode = %s",
+    Dprintf("psyco_conn_lobject:     parameters: oid = %u, mode = %s",
             oid, smode);
     Dprintf("psyco_conn_lobject:     parameters: new_oid = %d, new_file = %s",
             new_oid, new_file);
 
     if (new_file)
-        obj = PyObject_CallFunction(factory, "Oisis",
+        obj = PyObject_CallFunction(factory, "OIsIs",
             self, oid, smode, new_oid, new_file);
     else
-        obj = PyObject_CallFunction(factory, "Oisi",
+        obj = PyObject_CallFunction(factory, "OIsI",
             self, oid, smode, new_oid);
 
     if (obj == NULL) return NULL;

psycopg/lobject_type.c

@@ -371,18 +371,18 @@ lobject_dealloc(PyObject* obj)
 static int
 lobject_init(PyObject *obj, PyObject *args, PyObject *kwds)
 {
-    int oid = (int)InvalidOid, new_oid = (int)InvalidOid;
+    Oid oid = InvalidOid, new_oid = InvalidOid;
     const char *smode = "";
     const char *new_file = NULL;
     PyObject *conn = NULL;
 
-    if (!PyArg_ParseTuple(args, "O!|iziz",
+    if (!PyArg_ParseTuple(args, "O!|IzIz",
          &connectionType, &conn,
          &oid, &smode, &new_oid, &new_file))
         return -1;
 
     return lobject_setup((lobjectObject *)obj,
-        (connectionObject *)conn, (Oid)oid, smode, (Oid)new_oid, new_file);
+        (connectionObject *)conn, oid, smode, new_oid, new_file);
 }
 
 static PyObject *

tests/test_lobject.py

@@ -373,6 +373,12 @@ class LargeObjectTests(LargeObjectTestCase):
         finally:
             self.conn.tpc_commit()
 
+    def test_large_oid(self):
+        # Test we don't overflow with an oid not fitting a signed int
+        try:
+            self.conn.lobject(0xFFFFFFFE)
+        except psycopg2.OperationalError:
+            pass
 
 decorate_all_tests(LargeObjectTests, skip_if_no_lo, skip_lo_if_green)