Re: [PATCH] serial: 8250: Check for valid console index

[Ilpo Järvinen]

On Wed, 4 Oct 2023, Tony Lindgren wrote:

> * Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx> [231004 09:05]:
> > On Wed, 4 Oct 2023, Tony Lindgren wrote:
> > 
> > > Let's not allow negative numbers for console index.
> > > 
> > > Signed-off-by: Tony Lindgren <tony@xxxxxxxxxxx>
> > > ---
> > >  drivers/tty/serial/8250/8250_core.c | 2 +-
> > >  1 file changed, 1 insertion(+), 1 deletion(-)
> > > 
> > > diff --git a/drivers/tty/serial/8250/8250_core.c b/drivers/tty/serial/8250/8250_core.c
> > > --- a/drivers/tty/serial/8250/8250_core.c
> > > +++ b/drivers/tty/serial/8250/8250_core.c
> > > @@ -611,7 +611,7 @@ static int univ8250_console_setup(struct console *co, char *options)
> > >  	 * if so, search for the first available port that does have
> > >  	 * console support.
> > >  	 */
> > > -	if (co->index >= UART_NR)
> > > +	if (co->index < 0 || co->index >= UART_NR)
> > >  		co->index = 0;
> > 
> > The inconsistencies how different serial drivers handle this situation 
> > seem staggering. Perhaps there should be some effort to make the behavior
> > uniform across them?
> 
> Hmm yeah we should just have them all check for co->index < 0.

Right but it's only about that, some return -Exx codes (more than one -Exx 
variant) and some do assign just 0 like here.

-- 
 i.