From mboxrd@z Thu Jan 1 00:00:00 1970 From: Oliver Hartkopp Subject: Re: [PATCH] can: usb_8dev: unregister netdev before free()ing Date: Wed, 19 Jun 2013 18:29:12 +0200 Message-ID: <51C1DC58.2040705@hartkopp.net> References: <1371625369-26368-1-git-send-email-mkl@pengutronix.de> <1371625369-26368-2-git-send-email-mkl@pengutronix.de> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from mo-p00-ob.rzone.de ([81.169.146.161]:44091 "EHLO mo-p00-ob.rzone.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757195Ab3FSQ3Z (ORCPT ); Wed, 19 Jun 2013 12:29:25 -0400 In-Reply-To: <1371625369-26368-2-git-send-email-mkl@pengutronix.de> Sender: linux-can-owner@vger.kernel.org List-ID: To: Marc Kleine-Budde Cc: netdev@vger.kernel.org, linux-can@vger.kernel.org, davem@davemloft.net, stable@kernel.org, =?ISO-8859-1?Q?Bernd_Krumb=F6c?= =?ISO-8859-1?Q?k?= 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 > Reviewed-by: Bernd Krumboeck > Signed-off-by: Marc Kleine-Budde > --- > 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); > >