diff --git a/Misc/NEWS b/Misc/NEWS index e0ec447487a..f5a36f0f412 100644 --- a/Misc/NEWS +++ b/Misc/NEWS @@ -10,6 +10,9 @@ What's New in Python 3.7.0 alpha 1 Core and Builtins ----------------- +- Issue #23782: Fixed possible memory leak in _PyTraceback_Add() and exception + loss in PyTraceBack_Here(). + - Issue #28183: Optimize and cleanup dict iteration. - Issue #26081: Added C implementation of asyncio.Future. diff --git a/Python/traceback.c b/Python/traceback.c index e8aac1bad8e..9f8c568b08a 100644 --- a/Python/traceback.c +++ b/Python/traceback.c @@ -132,47 +132,53 @@ newtracebackobject(PyTracebackObject *next, PyFrameObject *frame) int PyTraceBack_Here(PyFrameObject *frame) { - PyThreadState *tstate = PyThreadState_GET(); - PyTracebackObject *oldtb = (PyTracebackObject *) tstate->curexc_traceback; - PyTracebackObject *tb = newtracebackobject(oldtb, frame); - if (tb == NULL) + PyObject *exc, *val, *tb, *newtb; + PyErr_Fetch(&exc, &val, &tb); + newtb = (PyObject *)newtracebackobject((PyTracebackObject *)tb, frame); + if (newtb == NULL) { + _PyErr_ChainExceptions(exc, val, tb); return -1; - tstate->curexc_traceback = (PyObject *)tb; - Py_XDECREF(oldtb); + } + PyErr_Restore(exc, val, newtb); + Py_XDECREF(tb); return 0; } /* Insert a frame into the traceback for (funcname, filename, lineno). */ void _PyTraceback_Add(const char *funcname, const char *filename, int lineno) { - PyObject *globals = NULL; - PyCodeObject *code = NULL; - PyFrameObject *frame = NULL; - PyObject *exception, *value, *tb; + PyObject *globals; + PyCodeObject *code; + PyFrameObject *frame; + PyObject *exc, *val, *tb; /* Save and clear the current exception. Python functions must not be called with an exception set. Calling Python functions happens when the codec of the filesystem encoding is implemented in pure Python. */ - PyErr_Fetch(&exception, &value, &tb); + PyErr_Fetch(&exc, &val, &tb); globals = PyDict_New(); if (!globals) - goto done; + goto error; code = PyCode_NewEmpty(filename, funcname, lineno); - if (!code) - goto done; + if (!code) { + Py_DECREF(globals); + goto error; + } frame = PyFrame_New(PyThreadState_Get(), code, globals, NULL); + Py_DECREF(globals); + Py_DECREF(code); if (!frame) - goto done; + goto error; frame->f_lineno = lineno; - PyErr_Restore(exception, value, tb); + PyErr_Restore(exc, val, tb); PyTraceBack_Here(frame); + Py_DECREF(frame); + return; -done: - Py_XDECREF(globals); - Py_XDECREF(code); - Py_XDECREF(frame); +error: + _PyErr_ChainExceptions(exc, val, tb); } static PyObject *