Re: [PATCH] perf data convert json: Fix trace_seq memory leak in process_sample_event()

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:

Pre-existing issues:
- [High] The `process_sample_event()` function leaks reference counts and memory associated with `struct addr_location` when a sample is skipped due to time filtering.
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commit de6e4710063f2942dd58ebe436d7d992872132b3
Author: Tanushree Shah <tshah@linux.ibm.com>

perf data convert json: Fix trace_seq memory leak in process_sample_event()

This commit fixes a memory leak by ensuring trace_seq_destroy() is called
to pair with trace_seq_init() when formatting tracepoint raw data.

> diff --git a/tools/perf/util/data-convert-json.c b/tools/perf/util/data-convert-json.c
> index d526c91312ed8..6dd9349ab10f1 100644
> --- a/tools/perf/util/data-convert-json.c
> +++ b/tools/perf/util/data-convert-json.c
> @@ -257,6 +257,7 @@ static int process_sample_event(const struct perf_tool *tool,
>  				trace_seq_init(&s);
>  				tep_print_field(&s, sample->raw_data, fields[i]);
>  				output_json_key_string(out, true, 3, fields[i]->name, s.buffer);
> +				trace_seq_destroy(&s);
>  
>  				i++;
>  			}

[Severity: High]
This is a pre-existing issue, but does the early return path for skipped
samples higher up in process_sample_event() leak the addr_location
reference handles?

tools/perf/util/data-convert-json.c:process_sample_event() {
        addr_location__init(&al);
        if (machine__resolve(machine, &al, sample) < 0) {
                pr_err("Sample resolution failed!\n");
                addr_location__exit(&al);
                return -1;
        }

        if (perf_time__ranges_skip_sample(c->ptime_range, c->range_num, sample->time)) {
                ++c->skipped;
                return 0;
        }
        ...
}

When machine__resolve() populates the addr_location structure, it acquires
reference handles for objects like thread and map. The early return for time
filtering bypasses the addr_location__exit() cleanup.

Could this cause reference counts and memory to leak when dropping skipped
samples?

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Sashiko AI review · https://sashiko.dev/#/patchset/20260604065519.112101-1-tshah@linux.ibm.com?part=1