From: Leo Yan <[email protected]>
[ Upstream commit f3c8d90757724982e5f07cd77d315eb64ca145ac ]
Based on the following report from Smatch, fix the potential
NULL pointer dereference check.
tools/perf/util/session.c:1252
dump_read() error: we previously assumed 'evsel' could be null
(see line 1249)
tools/perf/util/session.c
1240 static void dump_read(struct perf_evsel *evsel, union perf_event *event)
1241 {
1242 struct read_event *read_event = &event->read;
1243 u64 read_format;
1244
1245 if (!dump_trace)
1246 return;
1247
1248 printf(": %d %d %s %" PRIu64 "\n", event->read.pid,
event->read.tid,
1249 evsel ? perf_evsel__name(evsel) : "FAIL",
1250 event->read.value);
1251
1252 read_format = evsel->attr.read_format;
^^^^^^^
'evsel' could be NULL pointer, for this case this patch directly bails
out without dumping read_event.
Signed-off-by: Leo Yan <[email protected]>
Acked-by: Jiri Olsa <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Alexey Budankov <[email protected]>
Cc: Alexios Zavras <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Changbin Du <[email protected]>
Cc: David S. Miller <[email protected]>
Cc: Davidlohr Bueso <[email protected]>
Cc: Eric Saint-Etienne <[email protected]>
Cc: Jin Yao <[email protected]>
Cc: Konstantin Khlebnikov <[email protected]>
Cc: Mathieu Poirier <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Rasmus Villemoes <[email protected]>
Cc: Song Liu <[email protected]>
Cc: Suzuki Poulouse <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Thomas Richter <[email protected]>
Cc: [email protected]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
---
tools/perf/util/session.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
index 54cf163347f7..2e61dd6a3574 100644
--- a/tools/perf/util/session.c
+++ b/tools/perf/util/session.c
@@ -1249,6 +1249,9 @@ static void dump_read(struct perf_evsel *evsel, union
perf_event *event)
evsel ? perf_evsel__name(evsel) : "FAIL",
event->read.value);
+ if (!evsel)
+ return;
+
read_format = evsel->attr.read_format;
if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
--
2.20.1
