[ Upstream commit 08ef3af1579d0446db1c1bd08e2c42565addf10f ]
Numfor Mbiziwo-Tiapo reported segfault on stat of event group in repeat mode:
# perf stat -e '{cycles,instructions}' -r 10 ls
It's caused by memory corruption due to not cleaned evsel's id array and index, which needs to be rebuilt in every stat iteration. Currently the ids index grows, while the array (which is also not freed) has the same size.
Fixing this by releasing id array and zeroing ids index in perf_evsel__close function.
We also need to keep the evsel_list alive for stat record (which is disabled in repeat mode).
Reported-by: Numfor Mbiziwo-Tiapo nums@google.com Signed-off-by: Jiri Olsa jolsa@kernel.org Cc: Alexander Shishkin alexander.shishkin@linux.intel.com Cc: Ian Rogers irogers@google.com Cc: Mark Drayton mbd@fb.com Cc: Namhyung Kim namhyung@kernel.org Cc: Peter Zijlstra peterz@infradead.org Cc: Song Liu songliubraving@fb.com Cc: Stephane Eranian eranian@google.com Link: http://lkml.kernel.org/r/20190715142121.GC6032@krava Signed-off-by: Arnaldo Carvalho de Melo acme@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- tools/perf/builtin-stat.c | 9 ++++++++- tools/perf/util/evsel.c | 2 ++ 2 files changed, 10 insertions(+), 1 deletion(-)
diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c index e28002d905738..c6c550dbb9479 100644 --- a/tools/perf/builtin-stat.c +++ b/tools/perf/builtin-stat.c @@ -607,7 +607,13 @@ static int __run_perf_stat(int argc, const char **argv, int run_idx) * group leaders. */ read_counters(&(struct timespec) { .tv_nsec = t1-t0 }); - perf_evlist__close(evsel_list); + + /* + * We need to keep evsel_list alive, because it's processed + * later the evsel_list will be closed after. + */ + if (!STAT_RECORD) + perf_evlist__close(evsel_list);
return WEXITSTATUS(status); } @@ -1922,6 +1928,7 @@ int cmd_stat(int argc, const char **argv) perf_session__write_header(perf_stat.session, evsel_list, fd, true); }
+ perf_evlist__close(evsel_list); perf_session__delete(perf_stat.session); }
diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c index 2c46f9aa416c6..b854541604df5 100644 --- a/tools/perf/util/evsel.c +++ b/tools/perf/util/evsel.c @@ -1282,6 +1282,7 @@ static void perf_evsel__free_id(struct perf_evsel *evsel) xyarray__delete(evsel->sample_id); evsel->sample_id = NULL; zfree(&evsel->id); + evsel->ids = 0; }
static void perf_evsel__free_config_terms(struct perf_evsel *evsel) @@ -2074,6 +2075,7 @@ void perf_evsel__close(struct perf_evsel *evsel)
perf_evsel__close_fd(evsel); perf_evsel__free_fd(evsel); + perf_evsel__free_id(evsel); }
int perf_evsel__open_per_cpu(struct perf_evsel *evsel,