[PATCH 2/2] perf parse-events: Avoid an uninitialized read.

From: Ian Rogers
Date: Wed Aug 26 2020 - 00:29:25 EST


With a fake_pmu the pmu_info isn't populated by perf_pmu__check_alias.
In this case, don't try to copy the uninitialized values to the evsel.

Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>
---
tools/perf/util/parse-events.c | 30 +++++++++++++++++-------------
1 file changed, 17 insertions(+), 13 deletions(-)

diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index 9f7260e69113..3d7a48b488ed 100644
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c
@@ -1533,19 +1533,23 @@ int parse_events_add_pmu(struct parse_events_state *parse_state,
evsel = __add_event(list, &parse_state->idx, &attr, true,
get_config_name(head_config), pmu,
&config_terms, auto_merge_stats, NULL);
- if (evsel) {
- evsel->unit = info.unit;
- evsel->scale = info.scale;
- evsel->per_pkg = info.per_pkg;
- evsel->snapshot = info.snapshot;
- evsel->metric_expr = info.metric_expr;
- evsel->metric_name = info.metric_name;
- evsel->pmu_name = name ? strdup(name) : NULL;
- evsel->use_uncore_alias = use_uncore_alias;
- evsel->percore = config_term_percore(&evsel->config_terms);
- }
-
- return evsel ? 0 : -ENOMEM;
+ if (!evsel)
+ return -ENOMEM;
+
+ evsel->pmu_name = name ? strdup(name) : NULL;
+ evsel->use_uncore_alias = use_uncore_alias;
+ evsel->percore = config_term_percore(&evsel->config_terms);
+
+ if (parse_state->fake_pmu)
+ return 0;
+
+ evsel->unit = info.unit;
+ evsel->scale = info.scale;
+ evsel->per_pkg = info.per_pkg;
+ evsel->snapshot = info.snapshot;
+ evsel->metric_expr = info.metric_expr;
+ evsel->metric_name = info.metric_name;
+ return 0;
}

int parse_events_multi_pmu_add(struct parse_events_state *parse_state,
--
2.28.0.297.g1956fa8f8d-goog