perf tools: Pre-check sample size before parsing

Check that the total size of the sample fields having a fixed
size do not exceed the one of the whole event. This robustifies
the sample parsing.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Stephane Eranian <eranian@google.com>

1 files changed, 3 insertions, 2 deletions

diff --git a/tools/perf/util/python.c b/tools/perf/util/python.c
index 8b0eff8b8283..4174c0990320 100644
--- a/tools/perf/util/python.c
+++ b/tools/perf/util/python.c
@@ -690,8 +690,9 @@ static PyObject *pyrf_evlist__read_on_cpu(struct pyrf_evlist *pevlist,
                         return PyErr_NoMemory();
 
                 first = list_entry(evlist->entries.next, struct perf_evsel, node);
-                perf_event__parse_sample(event, first->attr.sample_type, sample_id_all,
-                                         &pevent->sample);
+                perf_event__parse_sample(event, first->attr.sample_type,
+                                         perf_sample_size(first->attr.sample_type),
+                                         sample_id_all, &pevent->sample);
                 return pyevent;
         }