linux-kernel - Re: [PATCH v3 04/16] virtio/console: verify device has config space

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]

Message-ID: <20150120104040.GJ31174@grmbl.mre>
Date:	Tue, 20 Jan 2015 16:10:40 +0530
From:	Amit Shah <amit.shah@...hat.com>
To:	"Michael S. Tsirkin" <mst@...hat.com>
Cc:	linux-kernel@...r.kernel.org,
	virtualization@...ts.linux-foundation.org,
	Rusty Russell <rusty@...tcorp.com.au>,
	cornelia.huck@...ibm.com, Arnd Bergmann <arnd@...db.de>,
	Greg Kroah-Hartman <gregkh@...uxfoundation.org>
Subject: Re: [PATCH v3 04/16] virtio/console: verify device has config space

On (Wed) 14 Jan 2015 [19:27:35], Michael S. Tsirkin wrote:
> Some devices might not implement config space access
> (e.g. remoteproc used not to - before 3.9).
> virtio/console needs config space access so make it
> fail gracefully if not there.

Do we know any such devices?  Wondering what prompted this patch.  If
it's just theoretical, I'd rather let it be like this, and pull this
in when there's a device that doesn't have config space.

Also, just the console functionality (i.e. F_MULTIPORT is unset) is
available w/o config space access.  In fact, getting this patch in
would mean remoteproc wouldn't even run in its pre-config days...

> diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c
> index de03df9..26afb56 100644
> --- a/drivers/char/virtio_console.c
> +++ b/drivers/char/virtio_console.c
> @@ -1986,6 +1986,12 @@ static int virtcons_probe(struct virtio_device *vdev)
>  	bool multiport;
>  	bool early = early_put_chars != NULL;
>  
> +	if (!vdev->config->get) {
> +		dev_err(&vdev->dev, "%s failure: config access disabled\n",
> +			__func__);
> +		return -EINVAL;
> +	}
> +


		Amit
--
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/