Re: [PATCH] ui/sdl2: fix segment fault caused by null pointer dereference

[Changbin Du]

On Mon, Apr 27, 2020 at 02:11:59PM +0100, Peter Maydell wrote:
> On Mon, 27 Apr 2020 at 13:19, Changbin Du <address@hidden> wrote:
> >
> > I found SDL_GetWindowFromID() sometimes return NULL when I start qemu via
> > ssh forwarding even the window has been crated already. I am not sure
> > whether this is a bug of SDL, but we'd better check it carefully.
> >
> > Signed-off-by: Changbin Du <address@hidden>
> > ---
> >  ui/sdl2.c | 9 +++++++++
> >  1 file changed, 9 insertions(+)
> >
> > diff --git a/ui/sdl2.c b/ui/sdl2.c
> > index 3c9424eb42..7c9c93b951 100644
> > --- a/ui/sdl2.c
> > +++ b/ui/sdl2.c
> > @@ -332,6 +332,9 @@ static void handle_keydown(SDL_Event *ev)
> >      int gui_key_modifier_pressed = get_mod_state();
> >      int gui_keysym = 0;
> >
> > +    if (!scon)
> > +        return;
> > +
> >      if (!scon->ignore_hotkeys && gui_key_modifier_pressed && 
> > !ev->key.repeat) {
> >          switch (ev->key.keysym.scancode) {
> >          case SDL_SCANCODE_2:
> > @@ -412,6 +415,9 @@ static void handle_keyup(SDL_Event *ev)
> >  {
> >      struct sdl2_console *scon = get_scon_from_window(ev->key.windowID);
> >
> > +    if (!sconf)
> > +        return;
> 
> It's generally a good idea to make sure your patch at least compiles
> before sending it :-)
>
sorry for this. I don't know why my make didn't recompile it after
changing.

> QEMU coding style demands {} on all if statements.
> 
sure.

> thanks
> -- PMM

-- 
Cheers,
Changbin Du