If the title is NULL then it can lead to a segv.

Fixes: 769e6a1e15bd ("perf ui browser: Don't save pointer to stack memory")
Signed-off-by: Ian Rogers <irogers@google.com>
---
 tools/perf/ui/browser.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/perf/ui/browser.c b/tools/perf/ui/browser.c
index c4cdf2ea69b7..19503e838738 100644
--- a/tools/perf/ui/browser.c
+++ b/tools/perf/ui/browser.c
@@ -203,7 +203,7 @@ void ui_browser__refresh_dimensions(struct ui_browser *browser)
 void ui_browser__handle_resize(struct ui_browser *browser)
 {
 	ui__refresh_dimensions(false);
-	ui_browser__show(browser, browser->title, ui_helpline__current);
+	ui_browser__show(browser, browser->title ?: "", ui_helpline__current);
 	ui_browser__refresh(browser);
 }
 
-- 
2.45.0.rc1.225.g2a3ae87e7f-goog

On Tue, May 7, 2024 at 8:53 PM Ian Rogers <irogers@google.com> wrote:
>
> If the title is NULL then it can lead to a segv.

Just out of curiosity, do you know where it sets to NULL?

Thanks,
Namhyung

>
> Fixes: 769e6a1e15bd ("perf ui browser: Don't save pointer to stack memory")
> Signed-off-by: Ian Rogers <irogers@google.com>
> ---
>  tools/perf/ui/browser.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/tools/perf/ui/browser.c b/tools/perf/ui/browser.c
> index c4cdf2ea69b7..19503e838738 100644
> --- a/tools/perf/ui/browser.c
> +++ b/tools/perf/ui/browser.c
> @@ -203,7 +203,7 @@ void ui_browser__refresh_dimensions(struct ui_browser *browser)
>  void ui_browser__handle_resize(struct ui_browser *browser)
>  {
>         ui__refresh_dimensions(false);
> -       ui_browser__show(browser, browser->title, ui_helpline__current);
> +       ui_browser__show(browser, browser->title ?: "", ui_helpline__current);
>         ui_browser__refresh(browser);
>  }
>
> --
> 2.45.0.rc1.225.g2a3ae87e7f-goog
>

On Wed, May 8, 2024 at 10:26 PM Namhyung Kim <namhyung@kernel.org> wrote:
>
> On Tue, May 7, 2024 at 8:53 PM Ian Rogers <irogers@google.com> wrote:
> >
> > If the title is NULL then it can lead to a segv.
>
> Just out of curiosity, do you know where it sets to NULL?

Yes, the fixes patch added strdup and zfree, the NULL is coming from the zfree.

Thanks,
Ian

> Thanks,
> Namhyung
>
> >
> > Fixes: 769e6a1e15bd ("perf ui browser: Don't save pointer to stack memory")
> > Signed-off-by: Ian Rogers <irogers@google.com>
> > ---
> >  tools/perf/ui/browser.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/tools/perf/ui/browser.c b/tools/perf/ui/browser.c
> > index c4cdf2ea69b7..19503e838738 100644
> > --- a/tools/perf/ui/browser.c
> > +++ b/tools/perf/ui/browser.c
> > @@ -203,7 +203,7 @@ void ui_browser__refresh_dimensions(struct ui_browser *browser)
> >  void ui_browser__handle_resize(struct ui_browser *browser)
> >  {
> >         ui__refresh_dimensions(false);
> > -       ui_browser__show(browser, browser->title, ui_helpline__current);
> > +       ui_browser__show(browser, browser->title ?: "", ui_helpline__current);
> >         ui_browser__refresh(browser);
> >  }
> >
> > --
> > 2.45.0.rc1.225.g2a3ae87e7f-goog
> >