Re: [PATCH] perf report TUI: Fix segmentation fault in perf_evsel__hists_browse()

[Arnaldo Carvalho de Melo]

Em Fri, Jul 03, 2020 at 09:03:53AM +0800, liwei (GF) escreveu:
> Ping...

Thanks, applied and tested, added the Acked-by Jiri and Namhyung
provided,

- Arnaldo
 
> On 2020/6/12 23:19, Namhyung Kim wrote:
> > Hello,
> > 
> > On Fri, Jun 12, 2020 at 6:58 PM Wei Li <liwei391@xxxxxxxxxx> wrote:
> >>
> >> The segmentation fault can be reproduced as following steps:
> >> 1) Executing perf report in tui.
> >> 2) Typing '/xxxxx' to filter the symbol to get nothing matched.
> >> 3) Pressing enter with no entry selected.
> >> Then it will report a segmentation fault.
> >>
> >> It is caused by the lack of check of browser->he_selection when
> >> accessing it's member res_samples in perf_evsel__hists_browse().
> >>
> >> These processes are meaningful for specified samples, so we can
> >> skip these when nothing is selected.
> >>
> >> Fixes: 4968ac8fb7c3 ("perf report: Implement browsing of individual samples")
> >> Signed-off-by: Wei Li <liwei391@xxxxxxxxxx>
> > 
> > Acked-by: Namhyung Kim <namhyung@xxxxxxxxxx>
> > 
> > Thanks
> > Namhyung
> > 
> > 
> >> ---
> >>  tools/perf/ui/browsers/hists.c | 17 +++++++++++------
> >>  1 file changed, 11 insertions(+), 6 deletions(-)
> >>
> >> diff --git a/tools/perf/ui/browsers/hists.c b/tools/perf/ui/browsers/hists.c
> >> index 487e54ef56a9..2101b6b770d8 100644
> >> --- a/tools/perf/ui/browsers/hists.c
> >> +++ b/tools/perf/ui/browsers/hists.c
> >> @@ -2288,6 +2288,11 @@ static struct thread *hist_browser__selected_thread(struct hist_browser *browser
> >>         return browser->he_selection->thread;
> >>  }
> >>
> >> +static struct res_sample *hist_browser__selected_res_sample(struct hist_browser *browser)
> >> +{
> >> +       return browser->he_selection ? browser->he_selection->res_samples : NULL;
> >> +}
> >> +
> >>  /* Check whether the browser is for 'top' or 'report' */
> >>  static inline bool is_report_browser(void *timer)
> >>  {
> >> @@ -3357,16 +3362,16 @@ static int perf_evsel__hists_browse(struct evsel *evsel, int nr_events,
> >>                                              &options[nr_options], NULL, NULL, evsel);
> >>                 nr_options += add_res_sample_opt(browser, &actions[nr_options],
> >>                                                  &options[nr_options],
> >> -                                hist_browser__selected_entry(browser)->res_samples,
> >> -                                evsel, A_NORMAL);
> >> +                                                hist_browser__selected_res_sample(browser),
> >> +                                                evsel, A_NORMAL);
> >>                 nr_options += add_res_sample_opt(browser, &actions[nr_options],
> >>                                                  &options[nr_options],
> >> -                                hist_browser__selected_entry(browser)->res_samples,
> >> -                                evsel, A_ASM);
> >> +                                                hist_browser__selected_res_sample(browser),
> >> +                                                evsel, A_ASM);
> >>                 nr_options += add_res_sample_opt(browser, &actions[nr_options],
> >>                                                  &options[nr_options],
> >> -                                hist_browser__selected_entry(browser)->res_samples,
> >> -                                evsel, A_SOURCE);
> >> +                                                hist_browser__selected_res_sample(browser),
> >> +                                                evsel, A_SOURCE);
> >>                 nr_options += add_switch_opt(browser, &actions[nr_options],
> >>                                              &options[nr_options]);
> >>  skip_scripting:
> >> --
> >> 2.17.1
> >>

-- 

- Arnaldo