[PATCH] can: usb_8dev: unregister netdev before free()ing

[PATCH] can: usb_8dev: unregister netdev before free()ing

[Marc Kleine-Budde]

The usb_8dev hardware has problems on some xhci USB hosts. The driver fails to
read the firmware revision in the probe function. This leads to the following
Oops:

    [ 3356.635912] kernel BUG at net/core/dev.c:5701!

The driver tries to free the netdev, which has already been registered, without
unregistering it.

This patch fixes the problem by unregistering the netdev in the error path.

Reported-by: <m.olbrich@pengutronix.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
---
 drivers/net/can/usb/usb_8dev.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/net/can/usb/usb_8dev.c b/drivers/net/can/usb/usb_8dev.c
index 6e15ef0..cbd388e 100644
--- a/drivers/net/can/usb/usb_8dev.c
+++ b/drivers/net/can/usb/usb_8dev.c
@@ -977,7 +977,7 @@ static int usb_8dev_probe(struct usb_interface *intf,
 	err = usb_8dev_cmd_version(priv, &version);
 	if (err) {
 		netdev_err(netdev, "can't get firmware version\n");
-		goto cleanup_cmd_msg_buffer;
+		goto cleanup_unregister_candev;
 	} else {
 		netdev_info(netdev,
 			 "firmware: %d.%d, hardware: %d.%d\n",
@@ -989,6 +989,9 @@ static int usb_8dev_probe(struct usb_interface *intf,
 
 	return 0;
 
+cleanup_unregister_candev:
+	unregister_netdev(priv->netdev);
+
 cleanup_cmd_msg_buffer:
 	kfree(priv->cmd_msg_buffer);
 
-- 
1.8.3.1

Re: [PATCH] can: usb_8dev: unregister netdev before free()ing

[Bernd Krumboeck]

Am 2013-06-18 14:57, schrieb Marc Kleine-Budde:
> The usb_8dev hardware has problems on some xhci USB hosts. The driver fails to
> read the firmware revision in the probe function. This leads to the following
> Oops:
>
>      [ 3356.635912] kernel BUG at net/core/dev.c:5701!
>
> The driver tries to free the netdev, which has already been registered, without
> unregistering it.
>
> This patch fixes the problem by unregistering the netdev in the error path.
>

Thank you for the patch!

I've applied it to my source tree:
https://github.com/krumboeck/usb2can


regards,
Bernd

Re: [PATCH] can: usb_8dev: unregister netdev before free()ing

[Marc Kleine-Budde]

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On 06/18/2013 08:23 PM, Bernd Krumboeck wrote:
> Am 2013-06-18 14:57, schrieb Marc Kleine-Budde:
>> The usb_8dev hardware has problems on some xhci USB hosts. The driver
>> fails to
>> read the firmware revision in the probe function. This leads to the
>> following
>> Oops:
>>
>>      [ 3356.635912] kernel BUG at net/core/dev.c:5701!
>>
>> The driver tries to free the netdev, which has already been
>> registered, without
>> unregistering it.
>>
>> This patch fixes the problem by unregistering the netdev in the error
>> path.
>>
> 
> Thank you for the patch!
> 
> I've applied it to my source tree:
> https://github.com/krumboeck/usb2can

Can I have you Acked-by or Reviewed-by?

Marc
-- 
Pengutronix e.K.                  | Marc Kleine-Budde           |
Industrial Linux Solutions        | Phone: +49-231-2826-924     |
Vertretung West/Dortmund          | Fax:   +49-5121-206917-5555 |
Amtsgericht Hildesheim, HRA 2686  | http://www.pengutronix.de   |


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Re: [PATCH] can: usb_8dev: unregister netdev before free()ing

[Bernd Krumboeck]

Am 2013-06-18 20:34, schrieb Marc Kleine-Budde:
> On 06/18/2013 08:23 PM, Bernd Krumboeck wrote:
>> Am 2013-06-18 14:57, schrieb Marc Kleine-Budde:
>>> The usb_8dev hardware has problems on some xhci USB hosts. The driver
>>> fails to
>>> read the firmware revision in the probe function. This leads to the
>>> following
>>> Oops:
>>>
>>>       [ 3356.635912] kernel BUG at net/core/dev.c:5701!
>>>
>>> The driver tries to free the netdev, which has already been
>>> registered, without
>>> unregistering it.
>>>
>>> This patch fixes the problem by unregistering the netdev in the error
>>> path.
>>>
>>
>> Thank you for the patch!
>>
>> I've applied it to my source tree:
>> https://github.com/krumboeck/usb2can
>
> Can I have you Acked-by or Reviewed-by?
>
> Marc
>

Yes, of course.

Please add "Reviewed-by: Bernd Krumboeck <krumboeck@universalnet.at>".


regards,
Bernd

Re: [PATCH] can: usb_8dev: unregister netdev before free()ing

[Marc Kleine-Budde]

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On 06/18/2013 10:20 PM, Bernd Krumboeck wrote:
>>>> The driver tries to free the netdev, which has already been
>>>> registered, without
>>>> unregistering it.
>>>>
>>>> This patch fixes the problem by unregistering the netdev in the error
>>>> path.
>>>>
>>>
>>> Thank you for the patch!
>>>
>>> I've applied it to my source tree:
>>> https://github.com/krumboeck/usb2can
>>
>> Can I have you Acked-by or Reviewed-by?
>>
>> Marc
>>
> 
> Yes, of course.
> 
> Please add "Reviewed-by: Bernd Krumboeck <krumboeck@universalnet.at>".

Tnx,
Marc

-- 
Pengutronix e.K.                  | Marc Kleine-Budde           |
Industrial Linux Solutions        | Phone: +49-231-2826-924     |
Vertretung West/Dortmund          | Fax:   +49-5121-206917-5555 |
Amtsgericht Hildesheim, HRA 2686  | http://www.pengutronix.de   |


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[PATCH] can: usb_8dev: unregister netdev before free()ing

[Marc Kleine-Budde]

The usb_8dev hardware has problems on some xhci USB hosts. The driver fails to
read the firmware revision in the probe function. This leads to the following
Oops:

    [ 3356.635912] kernel BUG at net/core/dev.c:5701!

The driver tries to free the netdev, which has already been registered, without
unregistering it.

This patch fixes the problem by unregistering the netdev in the error path.

Reported-by: Michael Olbrich <m.olbrich@pengutronix.de>
Reviewed-by: Bernd Krumboeck <krumboeck@universalnet.at>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
---
 drivers/net/can/usb/usb_8dev.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/net/can/usb/usb_8dev.c b/drivers/net/can/usb/usb_8dev.c
index 6e15ef0..cbd388e 100644
--- a/drivers/net/can/usb/usb_8dev.c
+++ b/drivers/net/can/usb/usb_8dev.c
@@ -977,7 +977,7 @@ static int usb_8dev_probe(struct usb_interface *intf,
 	err = usb_8dev_cmd_version(priv, &version);
 	if (err) {
 		netdev_err(netdev, "can't get firmware version\n");
-		goto cleanup_cmd_msg_buffer;
+		goto cleanup_unregister_candev;
 	} else {
 		netdev_info(netdev,
 			 "firmware: %d.%d, hardware: %d.%d\n",
@@ -989,6 +989,9 @@ static int usb_8dev_probe(struct usb_interface *intf,
 
 	return 0;
 
+cleanup_unregister_candev:
+	unregister_netdev(priv->netdev);
+
 cleanup_cmd_msg_buffer:
 	kfree(priv->cmd_msg_buffer);
 
-- 
1.8.3.1

Re: [PATCH] can: usb_8dev: unregister netdev before free()ing

[Oliver Hartkopp]

Hello Marc,

the usb_8dev driver was introduced in Linux 3.9 and therefore this reasonable
patch should be queued up for linux-3.9.y stable too.

Regards,
Oliver


On 19.06.2013 09:02, Marc Kleine-Budde wrote:
> The usb_8dev hardware has problems on some xhci USB hosts. The driver fails to
> read the firmware revision in the probe function. This leads to the following
> Oops:
> 
>     [ 3356.635912] kernel BUG at net/core/dev.c:5701!
> 
> The driver tries to free the netdev, which has already been registered, without
> unregistering it.
> 
> This patch fixes the problem by unregistering the netdev in the error path.
> 
> Reported-by: Michael Olbrich <m.olbrich@pengutronix.de>
> Reviewed-by: Bernd Krumboeck <krumboeck@universalnet.at>
> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
> ---
>  drivers/net/can/usb/usb_8dev.c | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/net/can/usb/usb_8dev.c b/drivers/net/can/usb/usb_8dev.c
> index 6e15ef0..cbd388e 100644
> --- a/drivers/net/can/usb/usb_8dev.c
> +++ b/drivers/net/can/usb/usb_8dev.c
> @@ -977,7 +977,7 @@ static int usb_8dev_probe(struct usb_interface *intf,
>  	err = usb_8dev_cmd_version(priv, &version);
>  	if (err) {
>  		netdev_err(netdev, "can't get firmware version\n");
> -		goto cleanup_cmd_msg_buffer;
> +		goto cleanup_unregister_candev;
>  	} else {
>  		netdev_info(netdev,
>  			 "firmware: %d.%d, hardware: %d.%d\n",
> @@ -989,6 +989,9 @@ static int usb_8dev_probe(struct usb_interface *intf,
>  
>  	return 0;
>  
> +cleanup_unregister_candev:
> +	unregister_netdev(priv->netdev);
> +
>  cleanup_cmd_msg_buffer:
>  	kfree(priv->cmd_msg_buffer);
>  
>