[PATCH 2/2] usbnet: don't clear urb->dev in tx_complete

URB unlinking is always racing with its completion and tx_complete
may be called before or during running usb_unlink_urb, so tx_complete
must not clear urb->dev since it will be used in unlink path,
otherwise invalid memory accesses or usb device leak may be caused
inside usb_unlink_urb.

Cc: stable@kernel.org
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Oliver Neukum <oliver@neukum.org>
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
---
 drivers/net/usb/usbnet.c |    1 -
 1 files changed, 0 insertions(+), 1 deletions(-)

diff --git a/drivers/net/usb/usbnet.c b/drivers/net/usb/usbnet.c
index febfdce..62f8b5c 100644
--- a/drivers/net/usb/usbnet.c
+++ b/drivers/net/usb/usbnet.c

@@ -1037,7 +1037,6 @@ static void tx_complete (struct urb *urb)
 	}
 
 	usb_autopm_put_interface_async(dev->intf);
-	urb->dev = NULL;
 	entry->state = tx_done;
 	defer_bh(dev, skb, &dev->txq);
 }

-- 
1.7.9.1

On Thu, Mar 22, 2012 at 09:22:38PM +0800, Ming Lei wrote:

URB unlinking is always racing with its completion and tx_complete
may be called before or during running usb_unlink_urb, so tx_complete
must not clear urb->dev since it will be used in unlink path,
otherwise invalid memory accesses or usb device leak may be caused
inside usb_unlink_urb.

Cc: stable@kernel.org
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Oliver Neukum <oliver@neukum.org>
Signed-off-by: Ming Lei <tom.leiming@gmail.com>

Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>