[PATCH 5.8 062/118] perf parse-event: Fix memory leak in evsel->unit

From: Greg Kroah-Hartman
Date: Mon Sep 21 2020 - 12:54:25 EST

From: Namhyung Kim <namhyung@xxxxxxxxxx>

[ Upstream commit b12eea5ad8e77f8a380a141e3db67c07432dde16 ]

The evsel->unit borrows a pointer of pmu event or alias instead of
owns a string. But tool event (duration_time) passes a result of
strdup() caused a leak.

It was found by ASAN during metric test:

Direct leak of 210 byte(s) in 70 object(s) allocated from:
#0 0x7fe366fca0b5 in strdup (/lib/x86_64-linux-gnu/libasan.so.5+0x920b5)
#1 0x559fbbcc6ea3 in add_event_tool util/parse-events.c:414
#2 0x559fbbcc6ea3 in parse_events_add_tool util/parse-events.c:1414
#3 0x559fbbd8474d in parse_events_parse util/parse-events.y:439
#4 0x559fbbcc95da in parse_events__scanner util/parse-events.c:2096
#5 0x559fbbcc95da in __parse_events util/parse-events.c:2141
#6 0x559fbbc28555 in check_parse_id tests/pmu-events.c:406
#7 0x559fbbc28555 in check_parse_id tests/pmu-events.c:393
#8 0x559fbbc28555 in check_parse_cpu tests/pmu-events.c:415
#9 0x559fbbc28555 in test_parsing tests/pmu-events.c:498
#10 0x559fbbc0109b in run_test tests/builtin-test.c:410
#11 0x559fbbc0109b in test_and_print tests/builtin-test.c:440
#12 0x559fbbc03e69 in __cmd_test tests/builtin-test.c:695
#13 0x559fbbc03e69 in cmd_test tests/builtin-test.c:807
#14 0x559fbbc691f4 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:312
#15 0x559fbbb071a8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:364
#16 0x559fbbb071a8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:408
#17 0x559fbbb071a8 in main /home/namhyung/project/linux/tools/perf/perf.c:538
#18 0x7fe366b68cc9 in __libc_start_main ../csu/libc-start.c:308

Fixes: f0fbb114e3025 ("perf stat: Implement duration_time as a proper event")
Signed-off-by: Namhyung Kim <namhyung@xxxxxxxxxx>
Acked-by: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
Cc: Andi Kleen <ak@xxxxxxxxxxxxxxx>
Cc: Ian Rogers <irogers@xxxxxxxxxx>
Cc: Mark Rutland <mark.rutland@xxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Stephane Eranian <eranian@xxxxxxxxxx>
Link: http://lore.kernel.org/lkml/20200915031819.386559-6-namhyung@xxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
tools/perf/util/parse-events.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index 4476de0e678aa..c1120d8196fae 100644
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c
@@ -410,7 +410,7 @@ static int add_event_tool(struct list_head *list, int *idx,
return -ENOMEM;
evsel->tool_event = tool_event;
if (tool_event == PERF_TOOL_DURATION_TIME)
- evsel->unit = strdup("ns");
+ evsel->unit = "ns";
return 0;