[PATCH 04/11] perf parse-event: Fix cpu map leaks

Namhyung Kim
2020-09-15T03:19:07Z

Like evlist cpu map, evsel's cpu map should have proper refcount by
releasing the original count after creation.

This fixes the following ASAN report:

Direct leak of 840 byte(s) in 70 object(s) allocated from:
#0 0x7fe36703f628 in malloc (/lib/x86_64-linux-gnu/libasan.so.5+0x107628)
#1 0x559fbbf611ca in cpu_map__trim_new /home/namhyung/project/linux/tools/lib/perf/cpumap.c:79
#2 0x559fbbf6229c in perf_cpu_map__new /home/namhyung/project/linux/tools/lib/perf/cpumap.c:237
#3 0x559fbbcc6c6d in __add_event util/parse-events.c:357
#4 0x559fbbcc6c6d in add_event_tool util/parse-events.c:408
#5 0x559fbbcc6c6d in parse_events_add_tool util/parse-events.c:1414
#6 0x559fbbd8474d in parse_events_parse util/parse-events.y:439
#7 0x559fbbcc95da in parse_events__scanner util/parse-events.c:2096
#8 0x559fbbcc95da in __parse_events util/parse-events.c:2141
#9 0x559fbbc2788b in check_parse_id tests/pmu-events.c:406
#10 0x559fbbc2788b in check_parse_id tests/pmu-events.c:393
#11 0x559fbbc2788b in check_parse_fake tests/pmu-events.c:436
#12 0x559fbbc2788b in metric_parse_fake tests/pmu-events.c:553
#13 0x559fbbc27e2d in test_parsing_fake tests/pmu-events.c:599
#14 0x559fbbc27e2d in test_parsing_fake tests/pmu-events.c:574
#15 0x559fbbc0109b in run_test tests/builtin-test.c:410
#16 0x559fbbc0109b in test_and_print tests/builtin-test.c:440
#17 0x559fbbc03e69 in __cmd_test tests/builtin-test.c:695
#18 0x559fbbc03e69 in cmd_test tests/builtin-test.c:807
#19 0x559fbbc691f4 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:312
#20 0x559fbbb071a8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:364
#21 0x559fbbb071a8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:408
#22 0x559fbbb071a8 in main /home/namhyung/project/linux/tools/perf/perf.c:538
#23 0x7fe366b68cc9 in __libc_start_main ../csu/libc-start.c:308

And I've failed which commit introduced this bug as the code was
heavily changed since then. ;-/

Acked-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
---
tools/perf/util/parse-events.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index c4d2394e2b2d..b35e4bb1cecb 100644
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c
@@ -360,8 +360,11 @@ __add_event(struct list_head *list, int *idx,
event_attr_init(attr);

evsel = evsel__new_idx(attr, *idx);
- if (!evsel)
+ if (!evsel) {
+ if (!pmu)
+ perf_cpu_map__put(cpus);
return NULL;
+ }

(*idx)++;
evsel->core.cpus = perf_cpu_map__get(cpus);
@@ -369,6 +372,8 @@ __add_event(struct list_head *list, int *idx,
evsel->core.system_wide = pmu ? pmu->is_uncore : false;
evsel->auto_merge_stats = auto_merge_stats;

+ if (!pmu)
+ perf_cpu_map__put(cpus);
if (name)
evsel->name = strdup(name);

--
2.28.0.618.gf4bc123cb7-goog