Re: [PATCH] perf parse-events: Avoid free on non malloc-ed memory

[Arnaldo Carvalho de Melo <arnaldo.melo@gmail.com>]

Em Tue, May 12, 2020 at 04:52:02PM -0700, Ian Rogers escreveu:
> Caught by libfuzzer, there is a segfault with:
> $ perf stat -e i/bs,tsc,L2/o sleep 1
> As a config_term is added that isn't a string.

Yeah, I've just applied a similar patch after looking at your private
report, added the same fixes, used your reproducer,

Thanks,

- Arnaldo
 
> Fixes: e8dfb81838b1 (perf parse-events: Fix memory leaks found on parse_events)
> Signed-off-by: Ian Rogers <irogers@google.com>
> ---
>  tools/perf/util/parse-events.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
> index e9464b04f149..e37a6a3e6217 100644
> --- a/tools/perf/util/parse-events.c
> +++ b/tools/perf/util/parse-events.c
> @@ -1480,7 +1480,8 @@ int parse_events_add_pmu(struct parse_events_state *parse_state,
>  
>  		list_for_each_entry_safe(pos, tmp, &config_terms, list) {
>  			list_del_init(&pos->list);
> -			zfree(&pos->val.str);
> +			if (pos->free_str)
> +				zfree(&pos->val.str);
>  			free(pos);
>  		}
>  		return -EINVAL;
> -- 
> 2.26.2.645.ge9eca65c58-goog
> 

-- 

- Arnaldo