Re: [PATCH v3 11/15] perf python: Add thread and PMU uninitialized checks

[Namhyung Kim <namhyung@kernel.org>]

Hello,

On Sun, Aug 09, 2026 at 07:28:09AM +0000, sashiko-bot@kernel.org wrote:
> Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
> - [Medium] The newly added `CHECK_INITIALIZED(ppmu->pmu, "pmu")` in `pyrf_pmu__events()` causes a Python object memory leak of `py_list` on the error path.
> --
> 
> --- Patch [11]: [PATCH v3 11/15] perf python: Add thread and PMU uninitialized checks ---
> commit a381b82bb0eb00b93be525bfa1c265b574c03a5a
> Author: Ian Rogers <irogers@google.com>
> 
> perf python: Add thread and PMU uninitialized checks
> 
> This commit adds CHECK_INITIALIZED guards to thread and PMU getters to
> prevent crashes when accessed before proper initialization.
> 
> > diff --git a/tools/perf/util/python.c b/tools/perf/util/python.c
> > index c70b151428f76..fe5afce173330 100644
> > --- a/tools/perf/util/python.c
> > +++ b/tools/perf/util/python.c
> 
> [ ... ]
> 
> > @@ -1730,6 +1731,8 @@ static PyObject *pyrf_pmu__events(PyObject *self)
> >  	PyObject *py_list = PyList_New(0);
> >  	int ret;
> >  
> > +	CHECK_INITIALIZED(ppmu->pmu, "pmu");
> > +
> >  	if (!py_list)
> >  		return NULL;
> 
> [Severity: Medium]
> Does this code leak py_list if CHECK_INITIALIZED fails and returns early?
> 
> Since py_list is allocated with PyList_New(0) just before the initialization
> check, it appears this Python object is left orphaned if the macro evaluates
> to true and forces an early return. 
> 
> Could the CHECK_INITIALIZED macro be moved to the beginning of
> pyrf_pmu__events() before the PyList_New(0) allocation to avoid this leak?

It seems this is the only issue introduced in this series.
As it's trivial, I'll apply the following change for Ian.

Thanks,
Namhyung


diff --git a/tools/perf/util/python.c b/tools/perf/util/python.c
index fe5afce1733306be..36c5f4b0d0bb15e7 100644
--- a/tools/perf/util/python.c
+++ b/tools/perf/util/python.c
@@ -1728,11 +1728,12 @@ static int pyrf_pmu__events_cb(void *state, struct pmu_event_info *info)
 static PyObject *pyrf_pmu__events(PyObject *self)
 {
        struct pyrf_pmu *ppmu = (void *)self;
-       PyObject *py_list = PyList_New(0);
+       PyObject *py_list;
        int ret;
 
        CHECK_INITIALIZED(ppmu->pmu, "pmu");
 
+       py_list = PyList_New(0);
        if (!py_list)
                return NULL;