From: Arnaldo Carvalho de Melo acme@redhat.com
[ Upstream commit 36d3e4138e1b6cc9ab179f3f397b5548f8b1eaae ]
When printing output we may want to generate per event files, where the --per-event-dump option should be used, creating perf.data.EVENT.dump files instead of printing to stdout.
The callback thar processes event thus expects that evsel->priv->fp should point to either the per-event FILE descriptor or to stdout.
The a3af66f51bd0bca7 ("perf script: Fix crash because of missing evsel->priv") changeset fixed a case where evsel->priv wasn't setup, thus set to NULL, causing a segfault when trying to access evsel->priv->fp.
But it did it for the non --per-event-dump case by allocating a 'struct perf_evsel_script' just to set its ->fp to stdout.
Since evsel->priv is only freed when --per-event-dump is used, we ended up with a memory leak, detected using ASAN.
Fix it by using the same method as perf_script__setup_per_event_dump(), and reuse that static 'struct perf_evsel_script'.
Also check if evsel_script__new() failed.
Fixes: a3af66f51bd0bca7 ("perf script: Fix crash because of missing evsel->priv") Reported-by: Ian Rogers irogers@google.com Tested-by: Ian Rogers irogers@google.com Cc: Adrian Hunter adrian.hunter@intel.com Cc: Jiri Olsa jolsa@kernel.org Cc: Namhyung Kim namhyung@kernel.org Cc: Ravi Bangoria ravi.bangoria@linux.ibm.com Link: https://lore.kernel.org/lkml/ZH+F0wGAWV14zvMP@kernel.org Signed-off-by: Arnaldo Carvalho de Melo acme@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- tools/perf/builtin-script.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-)
diff --git a/tools/perf/builtin-script.c b/tools/perf/builtin-script.c index d8c174a719383..72a3faa28c394 100644 --- a/tools/perf/builtin-script.c +++ b/tools/perf/builtin-script.c @@ -2425,6 +2425,9 @@ static int process_sample_event(struct perf_tool *tool, return ret; }
+// Used when scr->per_event_dump is not set +static struct evsel_script es_stdout; + static int process_attr(struct perf_tool *tool, union perf_event *event, struct evlist **pevlist) { @@ -2433,7 +2436,6 @@ static int process_attr(struct perf_tool *tool, union perf_event *event, struct evsel *evsel, *pos; u64 sample_type; int err; - static struct evsel_script *es;
err = perf_event__process_attr(tool, event, pevlist); if (err) @@ -2443,14 +2445,13 @@ static int process_attr(struct perf_tool *tool, union perf_event *event, evsel = evlist__last(*pevlist);
if (!evsel->priv) { - if (scr->per_event_dump) { + if (scr->per_event_dump) { evsel->priv = evsel_script__new(evsel, scr->session->data); - } else { - es = zalloc(sizeof(*es)); - if (!es) + if (!evsel->priv) return -ENOMEM; - es->fp = stdout; - evsel->priv = es; + } else { // Replicate what is done in perf_script__setup_per_event_dump() + es_stdout.fp = stdout; + evsel->priv = &es_stdout; } }
@@ -2756,7 +2757,6 @@ static int perf_script__fopen_per_event_dump(struct perf_script *script) static int perf_script__setup_per_event_dump(struct perf_script *script) { struct evsel *evsel; - static struct evsel_script es_stdout;
if (script->per_event_dump) return perf_script__fopen_per_event_dump(script);