Re: [PATCH] console: avoid passing con=NULL to graphic_hw_update_done() In graphic_hw_update(), first select an existing console, a specific-console or active_console(if not specified), then updating the console.

[Gerd Hoffmann]

  Hi,

If you have an long commit message put it into the body not the subject
please.

On Sat, Nov 07, 2020 at 01:03:39AM +0800, lichun wrote:
> Signed-off-by: lichun <lichun@ruijie.com.cn>
> ---
>  ui/console.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/ui/console.c b/ui/console.c
> index e8e5970..e07d2c3 100644
> --- a/ui/console.c
> +++ b/ui/console.c
> @@ -270,10 +270,11 @@ void graphic_hw_update_done(QemuConsole *con)
>  void graphic_hw_update(QemuConsole *con)
>  {
>      bool async = false;
> +    con = con ? con : active_console;

con should not be NULL at this point.

Can you trigger a NULL pointer dereference here somehow?

thanks,
  Gerd