signals: Fix a bug when wrong keyword args are passed

When a wrong argument is passed, the signalTpInit function is
left early, leaving self.data uninitialized in the signal structure.
The function signalFree then crashes.

Task-number: PYSIDE-1603
Change-Id: I97549092198fab206d37643716af3db2d8201cde
Reviewed-by: Adrian Herrmann <adrian.herrmann@qt.io>
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@qt.io>
(cherry picked from commit 9a4dc0d17c7f8eef7ed3e34751d8d519fad3c69b)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>

1 files changed, 5 insertions, 3 deletions

diff --git a/sources/pyside6/libpyside/pysidesignal.cpp b/sources/pyside6/libpyside/pysidesignal.cpp
index d804987cd..a365d351f 100644
--- a/sources/pyside6/libpyside/pysidesignal.cpp
+++ b/sources/pyside6/libpyside/pysidesignal.cpp
@@ -271,9 +271,11 @@ static void signalFree(void *vself)
 {
     auto pySelf = reinterpret_cast<PyObject *>(vself);
     auto self = reinterpret_cast<PySideSignal *>(vself);
-    delete self->data->signalArguments;
-    delete self->data;
-    self->data = nullptr;
+    if (self->data) {
+        delete self->data->signalArguments;
+        delete self->data;
+        self->data = nullptr;
+    }
     Py_XDECREF(self->homonymousMethod);
     self->homonymousMethod = nullptr;