[PATCH 08/11] perf metric: Free metric when it failed to resolve

Namhyung Kim
2020-09-15T03:20:07Z

The metricgroup__add_metric() can find multiple match for a metric
group and it's possible to fail. Also it can fail in the middle like
in resolve_metric() even for single metric.

In those cases, the intermediate list and ids will be leaked like:

Direct leak of 3 byte(s) in 1 object(s) allocated from:
#0 0x7f4c938f40b5 in strdup (/lib/x86_64-linux-gnu/libasan.so.5+0x920b5)
#1 0x55f7e71c1bef in __add_metric util/metricgroup.c:683
#2 0x55f7e71c31d0 in add_metric util/metricgroup.c:906
#3 0x55f7e71c3844 in metricgroup__add_metric util/metricgroup.c:940
#4 0x55f7e71c488d in metricgroup__add_metric_list util/metricgroup.c:993
#5 0x55f7e71c488d in parse_groups util/metricgroup.c:1045
#6 0x55f7e71c60a4 in metricgroup__parse_groups_test util/metricgroup.c:1087
#7 0x55f7e71235ae in __compute_metric tests/parse-metric.c:164
#8 0x55f7e7124650 in compute_metric tests/parse-metric.c:196
#9 0x55f7e7124650 in test_recursion_fail tests/parse-metric.c:318
#10 0x55f7e7124650 in test__parse_metric tests/parse-metric.c:356
#11 0x55f7e70be09b in run_test tests/builtin-test.c:410
#12 0x55f7e70be09b in test_and_print tests/builtin-test.c:440
#13 0x55f7e70c101a in __cmd_test tests/builtin-test.c:661
#14 0x55f7e70c101a in cmd_test tests/builtin-test.c:807
#15 0x55f7e7126214 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:312
#16 0x55f7e6fc41a8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:364
#17 0x55f7e6fc41a8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:408
#18 0x55f7e6fc41a8 in main /home/namhyung/project/linux/tools/perf/perf.c:538
#19 0x7f4c93492cc9 in __libc_start_main ../csu/libc-start.c:308

Acked-by: Jiri Olsa <jolsa@redhat.com>
Fixes: 83de0b7d535de ("perf metric: Collect referenced metrics in struct metric_ref_node")
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
---
tools/perf/util/metricgroup.c | 17 ++++++++++++-----
1 file changed, 12 insertions(+), 5 deletions(-)

diff --git a/tools/perf/util/metricgroup.c b/tools/perf/util/metricgroup.c
index 53747df601fa..35bcaa8d11e9 100644
--- a/tools/perf/util/metricgroup.c
+++ b/tools/perf/util/metricgroup.c
@@ -940,7 +940,7 @@ static int metricgroup__add_metric(const char *metric, bool metric_no_group,

ret = add_metric(&list, pe, metric_no_group, &m, NULL, &ids);
if (ret)
- return ret;
+ goto out;

/*
* Process any possible referenced metrics
@@ -949,12 +949,14 @@ static int metricgroup__add_metric(const char *metric, bool metric_no_group,
ret = resolve_metric(metric_no_group,
&list, map, &ids);
if (ret)
- return ret;
+ goto out;
}

/* End of pmu events. */
- if (!has_match)
- return -EINVAL;
+ if (!has_match) {
+ ret = -EINVAL;
+ goto out;
+ }

list_for_each_entry(m, &list, nd) {
if (events->len > 0)
@@ -969,9 +971,14 @@ static int metricgroup__add_metric(const char *metric, bool metric_no_group,
}
}

+out:
+ /*
+ * add to metric_list so that they can be released
+ * even if it's failed
+ */
list_splice(&list, metric_list);
expr_ids__exit(&ids);
- return 0;
+ return ret;
}

static int metricgroup__add_metric_list(const char *list, bool metric_no_group,
--
2.28.0.618.gf4bc123cb7-goog