[PATCH 3.2 081/115] usbnet: cleanup after bind() in probe()

From: Ben Hutchings
Date: Tue Apr 26 2016 - 19:27:54 EST


3.2.80-rc1 review patch. If anyone has any objections, please let me know.

------------------

From: Oliver Neukum <oneukum@xxxxxxxx>

commit 1666984c8625b3db19a9abc298931d35ab7bc64b upstream.

In case bind() works, but a later error forces bailing
in probe() in error cases work and a timer may be scheduled.
They must be killed. This fixes an error case related to
the double free reported in
http://www.spinics.net/lists/netdev/msg367669.html
and needs to go on top of Linus' fix to cdc-ncm.

Signed-off-by: Oliver Neukum <ONeukum@xxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
drivers/net/usb/usbnet.c | 7 +++++++
1 file changed, 7 insertions(+)

--- a/drivers/net/usb/usbnet.c
+++ b/drivers/net/usb/usbnet.c
@@ -1486,6 +1486,13 @@ out3:
if (info->unbind)
info->unbind (dev, udev);
out1:
+ /* subdrivers must undo all they did in bind() if they
+ * fail it, but we may fail later and a deferred kevent
+ * may trigger an error resubmitting itself and, worse,
+ * schedule a timer. So we kill it all just in case.
+ */
+ cancel_work_sync(&dev->kevent);
+ del_timer_sync(&dev->delay);
free_netdev(net);
out:
usb_put_dev(xdev);