usbnet: cleanup after bind() in probe()

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.

Orabug: 23070825
CVE-2016-3951

Signed-off-by: Oliver Neukum <ONeukum@suse.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
(cherry picked from commit 1666984c8625b3db19a9abc298931d35ab7bc64b)
Signed-off-by: Kirtikar Kashyap <kirtikar.kashyap@oracle.com>
Reviewed-by: Jack Vogel <jack.vogel@oracle.com>

diff --git a/drivers/net/usb/usbnet.c b/drivers/net/usb/usbnet.c
index 3c86b107275a899f3748e4cfee82ab2bb43aff6b..ea5dbe492f658fbdddcfaf7680055627e700bb3f 100644 (file)
--- a/drivers/net/usb/usbnet.c
+++ b/drivers/net/usb/usbnet.c
@@ -1753,6 +1753,13 @@ 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:
        return status;