diff options
| author | Arnaldo Carvalho de Melo <acme@redhat.com> | 2025-03-12 17:31:41 -0300 |
|---|---|---|
| committer | Namhyung Kim <namhyung@kernel.org> | 2025-03-18 16:08:45 -0700 |
| commit | 89aaeaf84231157288035b366cb6300c1c6cac64 (patch) | |
| tree | 5ef1ecaf363779db5e149332200e69a230e4618e /tools/perf/util/python.c | |
| parent | f3fed3ae34d606819d87a63d970cc3092a5be7ab (diff) | |
perf python: Check if there is space to copy all the event
The pyrf_event__new() method copies the event obtained from the perf
ring buffer to a structure that will then be turned into a python object
for further consumption, so it copies perf_event.header.size bytes to
its 'event' member:
$ pahole -C pyrf_event /tmp/build/perf-tools-next/python/perf.cpython-312-x86_64-linux-gnu.so
struct pyrf_event {
PyObject ob_base; /* 0 16 */
struct evsel * evsel; /* 16 8 */
struct perf_sample sample; /* 24 312 */
/* XXX last struct has 7 bytes of padding, 2 holes */
/* --- cacheline 5 boundary (320 bytes) was 16 bytes ago --- */
union perf_event event; /* 336 4168 */
/* size: 4504, cachelines: 71, members: 4 */
/* member types with holes: 1, total: 2 */
/* paddings: 1, sum paddings: 7 */
/* last cacheline: 24 bytes */
};
$
It was doing so without checking if the event just obtained has more
than that space, fix it.
This isn't a proper, final solution, as we need to support larger
events, but for the time being we at least bounds check and document it.
Fixes: 877108e42b1b9ba6 ("perf tools: Initial python binding")
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Reviewed-by: Ian Rogers <irogers@google.com>
Link: https://lore.kernel.org/r/20250312203141.285263-7-acme@kernel.org
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Diffstat (limited to 'tools/perf/util/python.c')
| -rw-r--r-- | tools/perf/util/python.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/tools/perf/util/python.c b/tools/perf/util/python.c index 6a03341e1788..f3c05da25b4a 100644 --- a/tools/perf/util/python.c +++ b/tools/perf/util/python.c @@ -476,6 +476,11 @@ static PyObject *pyrf_event__new(const union perf_event *event) event->header.type == PERF_RECORD_SWITCH_CPU_WIDE)) return NULL; + // FIXME this better be dynamic or we need to parse everything + // before calling perf_mmap__consume(), including tracepoint fields. + if (sizeof(pevent->event) < event->header.size) + return NULL; + ptype = pyrf_event__type[event->header.type]; pevent = PyObject_New(struct pyrf_event, ptype); if (pevent != NULL) |