2017-01-26 18:39:25

by Larry Finger

[permalink] [raw]
Subject: [PATCH] rtlwifi: rtl_usb: Fix for URB leaking when doing ifconfig up/down

From: Michael Schenk <[email protected]>

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 <[email protected]>
Signed-off-by: Larry Finger <[email protected]>
Cc: Stable <[email protected]>
---

Kalle,

This fix should be sent upstream whenever possible.

It is an old bug.

Thanks,

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

diff --git a/drivers/net/wireless/realtek/rtlwifi/usb.c b/drivers/net/wireless/realtek/rtlwifi/usb.c
index 0bca263..4d989b8 100644
--- a/drivers/net/wireless/realtek/rtlwifi/usb.c
+++ b/drivers/net/wireless/realtek/rtlwifi/usb.c
@@ -818,12 +818,30 @@ static void rtl_usb_stop(struct ieee80211_hw *hw)
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);
}

--
2.10.2


2017-01-28 07:11:53

by Kalle Valo

[permalink] [raw]
Subject: Re: rtlwifi: rtl_usb: Fix for URB leaking when doing ifconfig up/down

Larry Finger <[email protected]> wrote:
> From: Michael Schenk <[email protected]>
>
> 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 <[email protected]>
> Signed-off-by: Larry Finger <[email protected]>
> Cc: Stable <[email protected]>

Patch applied to wireless-drivers-next.git, thanks.

575ddce05077 rtlwifi: rtl_usb: Fix for URB leaking when doing ifconfig up/down

--
https://patchwork.kernel.org/patch/9539941/

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from patchwork:

https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches