Re: [PATCH v2] perf: fix double free at function perf_hpp__reset_output_field

[Arnaldo Carvalho de Melo]

Em Mon, Mar 27, 2017 at 02:22:55PM +0800, changbin.du@xxxxxxxxx escreveu:
> From: Changbin Du <changbin.du@xxxxxxxxx>
> 
> Some perf_hpp_fmt both registered at field and sort list. For such
> instance, we only can free it when removed from the both lists. This
> function currently only used by self-test code, but still should fix
> it.

Looks sane, applying,

Jiri, Namhyung, please holler (or ack) if needed,

- Arnaldo
 
> Signed-off-by: Changbin Du <changbin.du@xxxxxxxxx>
> ---
> v2: removed redundant Signed-off.
> 
> ---
>  tools/perf/ui/hist.c | 25 +++++++++++++++----------
>  1 file changed, 15 insertions(+), 10 deletions(-)
> 
> diff --git a/tools/perf/ui/hist.c b/tools/perf/ui/hist.c
> index 5d632dc..f94b301 100644
> --- a/tools/perf/ui/hist.c
> +++ b/tools/perf/ui/hist.c
> @@ -609,20 +609,25 @@ static void fmt_free(struct perf_hpp_fmt *fmt)
>  
>  void perf_hpp__reset_output_field(struct perf_hpp_list *list)
>  {
> -	struct perf_hpp_fmt *fmt, *tmp;
> +	struct perf_hpp_fmt *field_fmt, *sort_fmt, *tmp1, *tmp2;
>  
>  	/* reset output fields */
> -	perf_hpp_list__for_each_format_safe(list, fmt, tmp) {
> -		list_del_init(&fmt->list);
> -		list_del_init(&fmt->sort_list);
> -		fmt_free(fmt);
> +	perf_hpp_list__for_each_format_safe(list, field_fmt, tmp1) {
> +		list_del_init(&field_fmt->list);
> +		/* reset sort keys */
> +		perf_hpp_list__for_each_sort_list_safe(list, sort_fmt, tmp2) {
> +			if (field_fmt == sort_fmt) {
> +				list_del_init(&field_fmt->sort_list);
> +				break;
> +			}
> +		}
> +		fmt_free(field_fmt);
>  	}
>  
> -	/* reset sort keys */
> -	perf_hpp_list__for_each_sort_list_safe(list, fmt, tmp) {
> -		list_del_init(&fmt->list);
> -		list_del_init(&fmt->sort_list);
> -		fmt_free(fmt);
> +	/* reset remaining sort keys */
> +	perf_hpp_list__for_each_sort_list_safe(list, sort_fmt, tmp1) {
> +		list_del_init(&sort_fmt->sort_list);
> +		fmt_free(sort_fmt);
>  	}
>  }
>  
> -- 
> 2.7.4