Re: [PATCH v5 1/2] perf tests: Add test for uncore event sorting

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] Memory leak of dynamically allocated strings on error and skip paths.
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commit df52a005ba8bea64e813a32dded17fb34900d4b6
Author: Ian Rogers <irogers@google.com>

perf tests: Add test for uncore event sorting

Add a test for uncore event sorting matching multiple PMUs to ensure evsels
are resorted properly when parsed with mixed PMUs.

> diff --git a/tools/perf/tests/uncore-event-sorting.c b/tools/perf/tests/uncore-event-sorting.c
> new file mode 100644
> --- /dev/null
> +++ b/tools/perf/tests/uncore-event-sorting.c

[ ... ]

> +	while ((pmu = perf_pmus__scan(pmu)) != NULL) {

[ ... ]

> +		m.event1 = m.event2 = NULL;
> +		perf_pmu__for_each_event(pmu, false, &m, event_cb);
> +
> +		if (m.event1 && m.event2) {
> +			pmu_prefix = strndup(pmu->name, len);
> +			break;
> +		}
> +		free(m.event1);
> +	}
> +
> +	if (!pmu_prefix) {
> +		pr_debug("No suitable uncore PMU found\n");
> +		return TEST_SKIP;
> +	}

Does this early return bypass cleanup and leak m.event1 and m.event2?

If strndup() fails to allocate memory during the loop, pmu_prefix remains
NULL. The loop breaks, and this check returns TEST_SKIP immediately without
freeing the strings allocated during the perf_pmu__for_each_event() callbacks.

> +
> +	evlist = evlist__new();
> +	if (!evlist)
> +		return TEST_FAIL;

Does returning directly here leak pmu_prefix, m.event1, and m.event2?

If this is updated to use the out_err cleanup path instead, will it
dereference uninitialized stack memory?

Calling goto out_err; here would jump to parse_events_error__exit(&err)
before parse_events_error__init(&err) has had a chance to initialize it.

> +
> +	snprintf(buf, sizeof(buf), "{%s/%s/,%s/%s/}", pmu_prefix, m.event1, pmu_prefix, m.event2);
> +	pr_debug("Parsing: %s\n", buf);
> +
> +	parse_events_error__init(&err);

[ ... ]

> +out_err:
> +	evlist__delete(evlist);
> +	parse_events_error__exit(&err);
> +	free(pmu_prefix);
> +	free(m.event1);
> +	free(m.event2);
> +	return ret;
> +}

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260518003704.2434308-1-irogers@google.com?part=1