From 375a8565e1a0f6e0327d50657ac0f08045012809 Mon Sep 17 00:00:00 2001 From: Alexandru Croitor Date: Mon, 5 Feb 2018 16:19:28 +0100 Subject: Fix usage of PyCFunction_GET_FLAGS in pysidesignal.cpp Using PyCFunction_GET_FLAGS is unsafe, because it does not check whether the argument given is actually a PyCFunction object. This macro needs to be replaced with the function equivalent PyCFunction_GetFlags for stable ABI patch, but this will cause a crash in PyCFunction_Call because we don't check the return value of PyCFunction_GetFlags to see if it fails. Rather than checking the return value, it is safe to preemptively add a PyCFunction_Check before calling the GetFlags function. This does not modify the logic behind signalCall function. The crashing test was homonymoussignalandmethod_test.py, so no new test is needed. Task-number: PYSIDE-593 Change-Id: Id9ac9c0dec454e8e1ce9516dc68af924372a34a9 Reviewed-by: Christian Tismer --- sources/pyside2/libpyside/pysidesignal.cpp | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) (limited to 'sources') diff --git a/sources/pyside2/libpyside/pysidesignal.cpp b/sources/pyside2/libpyside/pysidesignal.cpp index 9f60d2a41..04b1cf1f4 100644 --- a/sources/pyside2/libpyside/pysidesignal.cpp +++ b/sources/pyside2/libpyside/pysidesignal.cpp @@ -564,17 +564,26 @@ PyObject* signalCall(PyObject* self, PyObject* args, PyObject* kw) { PySideSignal* signal = reinterpret_cast(self); + // Native C++ signals can't be called like functions, thus we throw an exception. + // The only way calling a signal can succeed (the Python equivalent of C++'s operator() ) + // is when a method with the same name as the signal is attached to an object. + // An example is QProcess::error() (don't check the docs, but the source code of qprocess.h). if (!signal->homonymousMethod) { PyErr_SetString(PyExc_TypeError, "native Qt signal is not callable"); return 0; } descrgetfunc getDescriptor = signal->homonymousMethod->ob_type->tp_descr_get; - Shiboken::AutoDecRef homonymousMethod(getDescriptor(signal->homonymousMethod, 0, 0)); - if (PyCFunction_GET_FLAGS(homonymousMethod.object()) & METH_STATIC) + // Check if there exists a method with the same name as the signal, which is also a static + // method in C++ land. + Shiboken::AutoDecRef homonymousMethod(getDescriptor(signal->homonymousMethod, 0, 0)); + if (PyCFunction_Check(homonymousMethod) + && (PyCFunction_GET_FLAGS(homonymousMethod.object()) & METH_STATIC)) { return PyCFunction_Call(homonymousMethod, args, kw); + } + // Assumes homonymousMethod is not a static method. ternaryfunc callFunc = signal->homonymousMethod->ob_type->tp_call; return callFunc(homonymousMethod, args, kw); } -- cgit v1.2.3