From: tom.leiming@gmail.com <tom.leiming@gmail.com>
Date: Thu, 22 Mar 2012 03:22:38 +0000 (+0000)
Subject: usbnet: don't clear urb->dev in tx_complete
X-Git-Tag: firefly_0821_release~7541^2~1479
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=d6dbbeccac70f85972e8b7773cede113914c9730;p=firefly-linux-kernel-4.4.55.git

usbnet: don't clear urb->dev in tx_complete

commit 5d5440a835710d09f0ef18da5000541ec98b537a upstream.

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: 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>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/net/usb/usbnet.c b/drivers/net/usb/usbnet.c
index 9f9e5876bdf2..46a6b67ab856 100644
--- a/drivers/net/usb/usbnet.c
+++ b/drivers/net/usb/usbnet.c
@@ -1033,7 +1033,6 @@ 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);
 }