gh-84808: Handle errors returned by internal_connect()

korli · encukou · korli · commit 2621a3262858 · 2024-09-06T12:06:15.000+02:00
internal_connect() errors when returning -1 with exception set.

reported and proposed by Ryan C. Gordon
error handling scheme (raise, no raise) as suggested by encukou

Co-authored-by: Petr Viktorin &lt;encukou@gmail.com&gt;
diff --git a/Modules/socketmodule.c b/Modules/socketmodule.c
@@ -3405,6 +3405,18 @@ sock_connect_impl(PySocketSockObject *s, void* Py_UNUSED(data))
     return 1;
 }
 
+/* Common functionality for socket.connect and socket.connect_ex.
+ *
+ * If *raise* is set:
+ * - On success, return 0.
+ * - On any failure, return -1 with an exception set.
+ * If *raise* is zero:
+ * - On success, return 0.
+ * - On connect() failure, return errno (without an exception set)
+ * - On other error, return -1 with an exception set.
+ *
+ *   Note that -1 is a valid errno value on some systems.
+ */
 static int
 internal_connect(PySocketSockObject *s, struct sockaddr *addr, int addrlen,
                  int raise)
@@ -3489,8 +3501,10 @@ sock_connect(PySocketSockObject *s, PyObject *addro)
     }
 
     res = internal_connect(s, SAS2SA(&addrbuf), addrlen, 1);
-    if (res < 0)
+    if (res < 0) {
+        assert(PyErr_Occurred());
         return NULL;
+    }
 
     Py_RETURN_NONE;
 }
@@ -3520,8 +3534,9 @@ sock_connect_ex(PySocketSockObject *s, PyObject *addro)
     }
 
     res = internal_connect(s, SAS2SA(&addrbuf), addrlen, 0);
-    if (res < 0)
+    if (res == -1 && PyErr_Occurred()) {
         return NULL;
+    }
 
     return PyLong_FromLong((long) res);
 }
