perf parse-events: Fix 3 use after frees found with clang ASAN

[ Upstream commit d4953f7e ]

Reproducible with a clang asan build and then running perf test in
particular 'Parse event definition strings'.
Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: clang-built-linux@googlegroups.com
Link: http://lore.kernel.org/lkml/20200314170356.62914-1-irogers@google.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

tools/perf/util/evsel.c

@@ -1290,6 +1290,7 @@ void perf_evsel__exit(struct perf_evsel *evsel)
 	thread_map__put(evsel->threads);
 	zfree(&evsel->group_name);
 	zfree(&evsel->name);
+	zfree(&evsel->pmu_name);
 	perf_evsel__object.fini(evsel);
 }
 

tools/perf/util/parse-events.c

@@ -1261,7 +1261,7 @@ int parse_events_add_pmu(struct parse_events_state *parse_state,
 		attr.type = pmu->type;
 		evsel = __add_event(list, &parse_state->idx, &attr, NULL, pmu, NULL, auto_merge_stats);
 		if (evsel) {
-			evsel->pmu_name = name;
+			evsel->pmu_name = name ? strdup(name) : NULL;
 			evsel->use_uncore_alias = use_uncore_alias;
 			return 0;
 		} else {
@@ -1302,7 +1302,7 @@ int parse_events_add_pmu(struct parse_events_state *parse_state,
 		evsel->snapshot = info.snapshot;
 		evsel->metric_expr = info.metric_expr;
 		evsel->metric_name = info.metric_name;
-		evsel->pmu_name = name;
+		evsel->pmu_name = name ? strdup(name) : NULL;
 		evsel->use_uncore_alias = use_uncore_alias;
 	}