[PATCH v2 2/2] perf parse-event: Fix cpu map leaks

From: Namhyung Kim <namhyung@kernel.org>
To: Arnaldo Carvalho de Melo <acme@kernel.org>, Jiri Olsa <jolsa@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>,
	Peter Zijlstra <a.p.zijlstra@chello.nl>,
	Mark Rutland <mark.rutland@arm.com>,
	Alexander Shishkin <alexander.shishkin@linux.intel.com>,
	Stephane Eranian <eranian@google.com>,
	LKML <linux-kernel@vger.kernel.org>,
	Andi Kleen <ak@linux.intel.com>, Ian Rogers <irogers@google.com>
Subject: [PATCH v2 2/2] perf parse-event: Fix cpu map leaks
Date: Thu, 17 Sep 2020 15:02:19 +0900	[thread overview]
Message-ID: <20200917060219.1287863-2-namhyung@kernel.org> (raw)
In-Reply-To: <20200917060219.1287863-1-namhyung@kernel.org>

Like evlist cpu map, evsel's cpu map should have a proper refcount.
As it's created with a refcount, we don't need to get an extra count.
Thanks to Arnaldo for the simpler suggestion.

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 | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index 176a51698a64..fbe0d3143353 100644
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c
@@ -353,7 +353,7 @@ __add_event(struct list_head *list, int *idx,
 	    const char *cpu_list)
 {
 	struct evsel *evsel;
-	struct perf_cpu_map *cpus = pmu ? pmu->cpus :
+	struct perf_cpu_map *cpus = pmu ? perf_cpu_map__get(pmu->cpus) :
 			       cpu_list ? perf_cpu_map__new(cpu_list) : NULL;
 
 	if (init_attr)
@@ -366,7 +366,7 @@ __add_event(struct list_head *list, int *idx,
 	}
 
 	(*idx)++;
-	evsel->core.cpus   = perf_cpu_map__get(cpus);
+	evsel->core.cpus = cpus;
 	evsel->core.own_cpus = perf_cpu_map__get(cpus);
 	evsel->core.system_wide = pmu ? pmu->is_uncore : false;
 	evsel->auto_merge_stats = auto_merge_stats;
-- 
2.28.0.618.gf4bc123cb7-goog

