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Message-ID: <fa174980e5c9bdafae3426fffe45b97b37f69c84.camel@linux.ibm.com>
Subject: Re: [PATCH] scsi: ses: Handle enclosure with just a primary
 component gracefully
From:   James Bottomley <jejb@linux.ibm.com>
Reply-To: jejb@linux.ibm.com
To:     Jiri Kosina <jikos@kernel.org>,
        "Martin K. Petersen" <martin.petersen@oracle.com>
Cc:     linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org,
        Ding Hui <dinghui@sangfor.com.cn>,
        Michal Kolar <mich.k@seznam.cz>
Date:   Tue, 04 Apr 2023 16:26:08 -0400
In-Reply-To: <nycvar.YFH.7.76.2304042122270.29760@cbobk.fhfr.pm>
References: <nycvar.YFH.7.76.2304042122270.29760@cbobk.fhfr.pm>
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On Tue, 2023-04-04 at 21:23 +0200, Jiri Kosina wrote:
> From: Jiri Kosina <jkosina@suse.cz>
> 
> 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@sangfor.com.cn>.

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