wimax/i2400m: Fix potential urb refcnt leak

i2400mu_bus_bm_wait_for_ack() invokes usb_get_urb(), which increases the
refcount of the "notif_urb".

When i2400mu_bus_bm_wait_for_ack() returns, local variable "notif_urb"
becomes invalid, so the refcount should be decreased to keep refcount
balanced.

The issue happens in all paths of i2400mu_bus_bm_wait_for_ack(), which
forget to decrease the refcnt increased by usb_get_urb(), causing a
refcnt leak.

Fix this issue by calling usb_put_urb() before the
i2400mu_bus_bm_wait_for_ack() returns.

Signed-off-by: Xiyu Yang <xiyuyang19@fudan.edu.cn>
Signed-off-by: Xin Tan <tanxin.ctf@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/wimax/i2400m/usb-fw.c b/drivers/net/wimax/i2400m/usb-fw.c
index 529ebca..1f7709d 100644 (file)
--- a/drivers/net/wimax/i2400m/usb-fw.c
+++ b/drivers/net/wimax/i2400m/usb-fw.c
@@ -354,6 +354,7 @@ out:
                usb_autopm_put_interface(i2400mu->usb_iface);
        d_fnend(8, dev, "(i2400m %p ack %p size %zu) = %ld\n",
                i2400m, ack, ack_size, (long) result);
+       usb_put_urb(&notif_urb);
        return result;
 
 error_exceeded: