Re: [PATCH] scsi: ses: Handle enclosure with just a primary component gracefully

[James Bottomley]

On Tue, 2023-04-04 at 21:23 +0200, Jiri Kosina wrote:
> From: Jiri Kosina <jkosina@xxxxxxx>
> 
> This reverts 3fe97ff3d9493 ("scsi: ses: Don't attach if enclosure has
> no components") and introduces proper handling of case where there
> are no detected secondary components, but primary component
> (enumerated in num_enclosures) does exist. That fix was originally
> proposed by Ding Hui <dinghui@xxxxxxxxxxxxxx>.

I think everything in here looks fine except this:

> --- a/drivers/scsi/ses.c
> +++ b/drivers/scsi/ses.c
> @@ -509,9 +509,6 @@ static int ses_enclosure_find_by_addr(struct
> enclosure_device *edev,
>         int i;
>         struct ses_component *scomp;
>  
> -       if (!edev->component[0].scratch)
> -               return 0;
> -
>         for (i = 0; i < edev->components; i++) {
>                 scomp = edev->component[i].scratch;
>                 if (scomp->addr != efd->addr)

If you remove the check, then scomp could be NULL here and we'll oops
on scomp->addr.

Regards,

James