linux-kernel - Re: [PATCH v6 1/4] sg: use rwsem to solve race during exclusive open

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Wed, 28 Aug 2013 14:26:18 +0400
From:	James Bottomley <James.Bottomley@...senPartnership.com>
To:	Vaughan Cao <vaughan.cao@...cle.com>
Cc:	joern@...fs.org, dgilbert@...erlog.com, linux-scsi@...r.kernel.org,
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH v6 1/4] sg: use rwsem to solve race during exclusive open

On Wed, 2013-08-28 at 18:07 +0800, Vaughan Cao wrote:
> @@ -331,17 +330,20 @@ sg_open(struct inode *inode, struct file *filp)
>         }
>         if ((sfp = sg_add_sfp(sdp, dev)))
>                 filp->private_data = sfp;
> -       else {
> +               /* retval is already provably zero at this point
> because of the
> +                * check after retval =
> scsi_autopm_get_device(sdp->device))
> +                */
> +       else
> +               retval = -ENOMEM;
> +
> +       if (retval) {
> +sem_out:

There's still no need for the double if.  You know the value of retval
in each of the legs of the first if; its only non zero for the else leg,
so you can combine them thus:

        if ((sfp = sg_add_sfp(sdp, dev)))
                filp->private_data = sfp;
               /* retval is already provably zero at this point because of the
                * check after retval scsi_autopm_get_device(sdp->device))
                */
       else {
               retval = -ENOMEM;
 sem_out:
...

James



--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/