[PATCH v1] perf hwmon_pmu: Ensure hwmon key union is zeroed before use

From: Ian Rogers
Date: Tue Nov 19 2024 - 18:00:48 EST


Non-zero values led to mismatches in testing. This was reproducible
with -fsanitize=undefined.

Reported-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Closes: https://lore.kernel.org/lkml/Zzdtj0PEWEX3ATwL@x1/
Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>
---
tools/perf/util/hwmon_pmu.c | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/tools/perf/util/hwmon_pmu.c b/tools/perf/util/hwmon_pmu.c
index ac2245acdc6d..4d9d6f405434 100644
--- a/tools/perf/util/hwmon_pmu.c
+++ b/tools/perf/util/hwmon_pmu.c
@@ -274,7 +274,7 @@ static int hwmon_pmu__read_events(struct hwmon_pmu *pmu)
int number;
enum hwmon_item item;
bool alarm;
- union hwmon_pmu_event_key key = {};
+ union hwmon_pmu_event_key key = { .type_and_num = 0 };
struct hwmon_pmu_event_value *value;

if (ent->d_type != DT_REG)
@@ -560,7 +560,7 @@ bool hwmon_pmu__have_event(struct perf_pmu *pmu, const char *name)
struct hwmon_pmu *hwm = container_of(pmu, struct hwmon_pmu, pmu);
enum hwmon_type type;
int number;
- union hwmon_pmu_event_key key = {};
+ union hwmon_pmu_event_key key = { .type_and_num = 0 };
struct hashmap_entry *cur;
size_t bkt;

@@ -623,10 +623,11 @@ static int hwmon_pmu__config_term(const struct hwmon_pmu *hwm,
return -EINVAL;
} else {
union hwmon_pmu_event_key key = {
- .type = type,
- .num = number,
+ .type_and_num = 0,
};

+ key.type = type;
+ key.num = number;
attr->config = key.type_and_num;
}
return 0;
--
2.47.0.371.ga323438b13-goog