[PATCH 4.9 31/32] rtlwifi: rtl_usb: Fix for URB leaking when doing ifconfig up/down

From: Greg Kroah-Hartman
Date: Fri Feb 24 2017 - 03:47:47 EST


4.9-stable review patch. If anyone has any objections, please let me know.

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

From: Michael Schenk <michael.schenk@xxxxxxxxxxxxxxx>

commit 575ddce0507789bf9830d089557d2199d2f91865 upstream.

In the function rtl_usb_start we pre-allocate a certain number of urbs
for RX path but they will not be freed when calling rtl_usb_stop. This
results in leaking urbs when doing ifconfig up and down. Eventually,
the system has no available urbs.

Signed-off-by: Michael Schenk <michael.schenk@xxxxxxxxxxxxxxx>
Signed-off-by: Larry Finger <Larry.Finger@xxxxxxxxxxxx>
Signed-off-by: Kalle Valo <kvalo@xxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/net/wireless/realtek/rtlwifi/usb.c | 18 ++++++++++++++++++
1 file changed, 18 insertions(+)

--- a/drivers/net/wireless/realtek/rtlwifi/usb.c
+++ b/drivers/net/wireless/realtek/rtlwifi/usb.c
@@ -831,12 +831,30 @@ static void rtl_usb_stop(struct ieee8021
struct rtl_priv *rtlpriv = rtl_priv(hw);
struct rtl_hal *rtlhal = rtl_hal(rtl_priv(hw));
struct rtl_usb *rtlusb = rtl_usbdev(rtl_usbpriv(hw));
+ struct urb *urb;

/* should after adapter start and interrupt enable. */
set_hal_stop(rtlhal);
cancel_work_sync(&rtlpriv->works.fill_h2c_cmd);
/* Enable software */
SET_USB_STOP(rtlusb);
+
+ /* free pre-allocated URBs from rtl_usb_start() */
+ usb_kill_anchored_urbs(&rtlusb->rx_submitted);
+
+ tasklet_kill(&rtlusb->rx_work_tasklet);
+ cancel_work_sync(&rtlpriv->works.lps_change_work);
+
+ flush_workqueue(rtlpriv->works.rtl_wq);
+
+ skb_queue_purge(&rtlusb->rx_queue);
+
+ while ((urb = usb_get_from_anchor(&rtlusb->rx_cleanup_urbs))) {
+ usb_free_coherent(urb->dev, urb->transfer_buffer_length,
+ urb->transfer_buffer, urb->transfer_dma);
+ usb_free_urb(urb);
+ }
+
rtlpriv->cfg->ops->hw_disable(hw);
}