[PATCH v3 09/15] perf python: Validate attribute setters in pyrf_evsel

If val is NULL when setting an attribute, PyErr_SetString should be
called as deleting the attribute isn't supported. In addition, ensure
PyErr_Occurred is checked before setting the attribute to avoid setting
a garbage value.

Fixes: 877108e42b1b ("perf tools: Initial python binding")
Signed-off-by: Ian Rogers <[email protected]>
---
 tools/perf/util/python.c | 89 ++++++++++++++++++++++++++++++++++------
 1 file changed, 77 insertions(+), 12 deletions(-)

diff --git a/tools/perf/util/python.c b/tools/perf/util/python.c
index a1334400874c..848912401c4f 100644
--- a/tools/perf/util/python.c
+++ b/tools/perf/util/python.c
@@ -2301,6 +2301,11 @@ static int pyrf_evsel__set_tracking(PyObject *self, PyObject *val, void *closure
 
 	CHECK_INITIALIZED_INT(pevsel->evsel, "evsel");
 
+	if (val == NULL) {
+		PyErr_SetString(PyExc_TypeError, "cannot delete attribute");
+		return -1;
+	}
+
 	is_true = PyObject_IsTrue(val);
 	if (is_true < 0)
 		return -1;
@@ -2312,11 +2317,21 @@ static int pyrf_evsel__set_tracking(PyObject *self, PyObject *val, void *closure
 static int pyrf_evsel__set_attr_config(PyObject *self, PyObject *val, void *closure __maybe_unused)
 {
 	struct pyrf_evsel *pevsel = (void *)self;
+	unsigned long long new_val;
 
 	CHECK_INITIALIZED_INT(pevsel->evsel, "evsel");
 
-	pevsel->evsel->core.attr.config = PyLong_AsUnsignedLongLong(val);
-	return PyErr_Occurred() ? -1 : 0;
+	if (val == NULL) {
+		PyErr_SetString(PyExc_TypeError, "cannot delete attribute");
+		return -1;
+	}
+
+	new_val = PyLong_AsUnsignedLongLong(val);
+	if (PyErr_Occurred())
+		return -1;
+
+	pevsel->evsel->core.attr.config = new_val;
+	return 0;
 }
 
 static PyObject *pyrf_evsel__get_attr_config(PyObject *self, void *closure __maybe_unused)
@@ -2331,11 +2346,21 @@ static PyObject *pyrf_evsel__get_attr_config(PyObject *self, void *closure __may
 static int pyrf_evsel__set_attr_read_format(PyObject *self, PyObject *val, void *closure __maybe_unused)
 {
 	struct pyrf_evsel *pevsel = (void *)self;
+	unsigned long long new_val;
 
 	CHECK_INITIALIZED_INT(pevsel->evsel, "evsel");
 
-	pevsel->evsel->core.attr.read_format = PyLong_AsUnsignedLongLong(val);
-	return PyErr_Occurred() ? -1 : 0;
+	if (val == NULL) {
+		PyErr_SetString(PyExc_TypeError, "cannot delete attribute");
+		return -1;
+	}
+
+	new_val = PyLong_AsUnsignedLongLong(val);
+	if (PyErr_Occurred())
+		return -1;
+
+	pevsel->evsel->core.attr.read_format = new_val;
+	return 0;
 }
 
 static PyObject *pyrf_evsel__get_attr_read_format(PyObject *self, void *closure __maybe_unused)
@@ -2350,11 +2375,21 @@ static PyObject *pyrf_evsel__get_attr_read_format(PyObject *self, void *closure
 static int pyrf_evsel__set_attr_sample_period(PyObject *self, PyObject *val, void *closure __maybe_unused)
 {
 	struct pyrf_evsel *pevsel = (void *)self;
+	unsigned long long new_val;
 
 	CHECK_INITIALIZED_INT(pevsel->evsel, "evsel");
 
-	pevsel->evsel->core.attr.sample_period = PyLong_AsUnsignedLongLong(val);
-	return PyErr_Occurred() ? -1 : 0;
+	if (val == NULL) {
+		PyErr_SetString(PyExc_TypeError, "cannot delete attribute");
+		return -1;
+	}
+
+	new_val = PyLong_AsUnsignedLongLong(val);
+	if (PyErr_Occurred())
+		return -1;
+
+	pevsel->evsel->core.attr.sample_period = new_val;
+	return 0;
 }
 
 static PyObject *pyrf_evsel__get_attr_sample_period(PyObject *self, void *closure __maybe_unused)
@@ -2369,11 +2404,21 @@ static PyObject *pyrf_evsel__get_attr_sample_period(PyObject *self, void *closur
 static int pyrf_evsel__set_attr_sample_type(PyObject *self, PyObject *val, void *closure __maybe_unused)
 {
 	struct pyrf_evsel *pevsel = (void *)self;
+	unsigned long long new_val;
 
 	CHECK_INITIALIZED_INT(pevsel->evsel, "evsel");
 
-	pevsel->evsel->core.attr.sample_type = PyLong_AsUnsignedLongLong(val);
-	return PyErr_Occurred() ? -1 : 0;
+	if (val == NULL) {
+		PyErr_SetString(PyExc_TypeError, "cannot delete attribute");
+		return -1;
+	}
+
+	new_val = PyLong_AsUnsignedLongLong(val);
+	if (PyErr_Occurred())
+		return -1;
+
+	pevsel->evsel->core.attr.sample_type = new_val;
+	return 0;
 }
 
 static PyObject *pyrf_evsel__get_attr_sample_type(PyObject *self, void *closure __maybe_unused)
@@ -2397,11 +2442,21 @@ static PyObject *pyrf_evsel__get_attr_size(PyObject *self, void *closure __maybe
 static int pyrf_evsel__set_attr_type(PyObject *self, PyObject *val, void *closure __maybe_unused)
 {
 	struct pyrf_evsel *pevsel = (void *)self;
+	unsigned long new_val;
 
 	CHECK_INITIALIZED_INT(pevsel->evsel, "evsel");
 
-	pevsel->evsel->core.attr.type = PyLong_AsUnsignedLong(val);
-	return PyErr_Occurred() ? -1 : 0;
+	if (val == NULL) {
+		PyErr_SetString(PyExc_TypeError, "cannot delete attribute");
+		return -1;
+	}
+
+	new_val = PyLong_AsUnsignedLong(val);
+	if (PyErr_Occurred())
+		return -1;
+
+	pevsel->evsel->core.attr.type = new_val;
+	return 0;
 }
 
 static PyObject *pyrf_evsel__get_attr_type(PyObject *self, void *closure __maybe_unused)
@@ -2416,11 +2471,21 @@ static PyObject *pyrf_evsel__get_attr_type(PyObject *self, void *closure __maybe
 static int pyrf_evsel__set_attr_wakeup_events(PyObject *self, PyObject *val, void *closure __maybe_unused)
 {
 	struct pyrf_evsel *pevsel = (void *)self;
+	unsigned long new_val;
 
 	CHECK_INITIALIZED_INT(pevsel->evsel, "evsel");
 
-	pevsel->evsel->core.attr.wakeup_events = PyLong_AsUnsignedLong(val);
-	return PyErr_Occurred() ? -1 : 0;
+	if (val == NULL) {
+		PyErr_SetString(PyExc_TypeError, "cannot delete attribute");
+		return -1;
+	}
+
+	new_val = PyLong_AsUnsignedLong(val);
+	if (PyErr_Occurred())
+		return -1;
+
+	pevsel->evsel->core.attr.wakeup_events = new_val;
+	return 0;
 }
 
 static PyObject *pyrf_evsel__get_attr_wakeup_events(PyObject *self, void *closure __maybe_unused)
-- 
2.55.0.679.g6767b8d81c-goog