[PATCH] rtl8xxxu: prevent potential memory leak

From: Chris Chiu
Date: Sun Sep 06 2020 - 00:04:49 EST


Free the skb if usb_submit_urb fails on rx_urb. And free the urb
no matter usb_submit_urb succeeds or not in rtl8xxxu_submit_int_urb.

Signed-off-by: Chris Chiu <chiu@xxxxxxxxxxxx>
---
drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c | 10 +++++++++-
1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c b/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c
index 19efae462a24..5cd7ef3625c5 100644
--- a/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c
+++ b/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c
@@ -5795,7 +5795,6 @@ static int rtl8xxxu_submit_int_urb(struct ieee80211_hw *hw)
ret = usb_submit_urb(urb, GFP_KERNEL);
if (ret) {
usb_unanchor_urb(urb);
- usb_free_urb(urb);
goto error;
}

@@ -5804,6 +5803,7 @@ static int rtl8xxxu_submit_int_urb(struct ieee80211_hw *hw)
rtl8xxxu_write32(priv, REG_USB_HIMR, val32);

error:
+ usb_free_urb(urb);
return ret;
}

@@ -6318,6 +6318,7 @@ static int rtl8xxxu_start(struct ieee80211_hw *hw)
struct rtl8xxxu_priv *priv = hw->priv;
struct rtl8xxxu_rx_urb *rx_urb;
struct rtl8xxxu_tx_urb *tx_urb;
+ struct sk_buff *skb;
unsigned long flags;
int ret, i;

@@ -6368,6 +6369,13 @@ static int rtl8xxxu_start(struct ieee80211_hw *hw)
rx_urb->hw = hw;

ret = rtl8xxxu_submit_rx_urb(priv, rx_urb);
+ if (ret) {
+ if (ret != -ENOMEM) {
+ skb = (struct sk_buff *)rx_urb->urb.context;
+ dev_kfree_skb(skb);
+ }
+ rtl8xxxu_queue_rx_urb(priv, rx_urb);
+ }
}

schedule_delayed_work(&priv->ra_watchdog, 2 * HZ);
--
2.20.1