linux-kernel - Re: [PATCH v2] usb: core: Unregister device on component

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] [day] [month] [year] [list]

Date:   Thu, 10 Feb 2022 16:29:22 +0200
From:   Heikki Krogerus <heikki.krogerus@...ux.intel.com>
To:     "Fabio M. De Francesco" <fmdefrancesco@...il.com>
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        "Rafael J. Wysocki" <rafael.j.wysocki@...el.com>,
        Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
        linux-usb@...r.kernel.org, linux-kernel@...r.kernel.org,
        syzbot+60df062e1c41940cae0f@...kaller.appspotmail.com
Subject: Re: [PATCH v2] usb: core: Unregister device on component_add()
 failure

On Wed, Feb 09, 2022 at 05:45:00PM +0100, Fabio M. De Francesco wrote:
> Commit 8c67d06f3fd9 ("usb: Link the ports to the connectors they are
> attached to") creates a link to the USB Type-C connector for every new
> port that is added when possible. If component_add() fails,
> usb_hub_create_port_device() prints a warning but does not unregister
> the device and does not return errors to the callers.
> 
> Syzbot reported a "WARNING in component_del()".
> 
> Fix this issue in usb_hub_create_port_device by calling device_unregister()
> and returning the errors from component_add().
> 
> Reported-and-tested-by: syzbot+60df062e1c41940cae0f@...kaller.appspotmail.com
> Fixes: 8c67d06f3fd9 ("usb: Link the ports to the connectors they are attached to")
> Signed-off-by: Fabio M. De Francesco <fmdefrancesco@...il.com>

FWIW:

Reviewed-by: Heikki Krogerus <heikki.krogerus@...ux.intel.com>

> ---
> 
> v1->v2: Move find_and_link_peer() soon after the 'if' test for "retval", 
> 	as suggested by Heikki Krogerus with his review of v1.
> 
>  drivers/usb/core/port.c | 9 ++++++---
>  1 file changed, 6 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/usb/core/port.c b/drivers/usb/core/port.c
> index c2bbf97a79be..d5bc36ca5b1f 100644
> --- a/drivers/usb/core/port.c
> +++ b/drivers/usb/core/port.c
> @@ -602,11 +602,14 @@ int usb_hub_create_port_device(struct usb_hub *hub, int port1)
>  		return retval;
>  	}
>  
> -	find_and_link_peer(hub, port1);
> -
>  	retval = component_add(&port_dev->dev, &connector_ops);
> -	if (retval)
> +	if (retval) {
>  		dev_warn(&port_dev->dev, "failed to add component\n");
> +		device_unregister(&port_dev->dev);
> +		return retval;
> +	}
> +
> +	find_and_link_peer(hub, port1);
>  
>  	/*
>  	 * Enable runtime pm and hold a refernce that hub_configure()
> -- 
> 2.34.1

-- 
heikki