Re: [PATCH] perf parse-events: fix memory leaks found on parse_events

From: Jiri Olsa
Date: Wed Mar 18 2020 - 06:40:26 EST


On Sun, Mar 15, 2020 at 09:14:31PM -0700, Ian Rogers wrote:
> Memory leaks found by applying LLVM's libfuzzer on the parse_events
> function.
>
> Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>
> ---
> tools/lib/perf/evlist.c | 2 ++
> tools/perf/util/parse-events.c | 2 ++
> tools/perf/util/parse-events.y | 3 ++-
> 3 files changed, 6 insertions(+), 1 deletion(-)
>
> diff --git a/tools/lib/perf/evlist.c b/tools/lib/perf/evlist.c
> index 5b9f2ca50591..6485d1438f75 100644
> --- a/tools/lib/perf/evlist.c
> +++ b/tools/lib/perf/evlist.c
> @@ -125,8 +125,10 @@ static void perf_evlist__purge(struct perf_evlist *evlist)
> void perf_evlist__exit(struct perf_evlist *evlist)
> {
> perf_cpu_map__put(evlist->cpus);
> + perf_cpu_map__put(evlist->all_cpus);

ugh, yes, could you please put it to separate libperf patch?

> perf_thread_map__put(evlist->threads);
> evlist->cpus = NULL;
> + evlist->all_cpus = NULL;

there's already change adding this waiting on the list:
https://lore.kernel.org/lkml/1583665157-349023-1-git-send-email-zhe.he@xxxxxxxxxxxxx/

> evlist->threads = NULL;
> fdarray__exit(&evlist->pollfd);
> }
> diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
> index a14995835d85..997862224292 100644
> --- a/tools/perf/util/parse-events.c
> +++ b/tools/perf/util/parse-events.c
> @@ -1482,6 +1482,8 @@ int parse_events_add_pmu(struct parse_events_state *parse_state,
>
> list_for_each_entry_safe(pos, tmp, &config_terms, list) {
> list_del_init(&pos->list);
> + if (pos->free_str)
> + free(pos->val.str);

ack, would be nice to have perf_evsel__free_config_terms generalized
to work directly over config terms list, so we'd have only single
cleanup function

> free(pos);
> }
> return -EINVAL;
> diff --git a/tools/perf/util/parse-events.y b/tools/perf/util/parse-events.y
> index 94f8bcd83582..8212cc771667 100644
> --- a/tools/perf/util/parse-events.y
> +++ b/tools/perf/util/parse-events.y
> @@ -44,7 +44,7 @@ static void free_list_evsel(struct list_head* list_evsel)
>
> list_for_each_entry_safe(evsel, tmp, list_evsel, core.node) {
> list_del_init(&evsel->core.node);
> - perf_evsel__delete(evsel);
> + evsel__delete(evsel);

ack

> }
> free(list_evsel);
> }
> @@ -326,6 +326,7 @@ PE_NAME opt_pmu_config
> }
> parse_events_terms__delete($2);
> parse_events_terms__delete(orig_terms);
> + free(pattern);

ack

could you please send the separate change for libperf?
and synchronize with that other patch mentioned above

thanks,
jirka