FAILED: patch "[PATCH] rsi: fix use-after-free on failed probe and unbind" failed to apply to 4.4-stable tree

[<gregkh@xxxxxxxxxxxxxxxxxxx>]

The patch below does not apply to the 4.4-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@xxxxxxxxxxxxxxx>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

>From e93cd35101b61e4c79149be2cfc927c4b28dc60c Mon Sep 17 00:00:00 2001
From: Johan Hovold <johan@xxxxxxxxxx>
Date: Thu, 28 Nov 2019 18:22:00 +0100
Subject: [PATCH] rsi: fix use-after-free on failed probe and unbind

Make sure to stop both URBs before returning after failed probe as well
as on disconnect to avoid use-after-free in the completion handler.

Reported-by: syzbot+b563b7f8dbe8223a51e8@xxxxxxxxxxxxxxxxxxxxxxxxx
Fixes: a4302bff28e2 ("rsi: add bluetooth rx endpoint")
Fixes: dad0d04fa7ba ("rsi: Add RS9113 wireless driver")
Cc: stable <stable@xxxxxxxxxxxxxxx>     # 3.15
Cc: Siva Rebbagondla <siva.rebbagondla@xxxxxxxxxxxxxxxxxx>
Cc: Prameela Rani Garnepudi <prameela.j04cs@xxxxxxxxx>
Cc: Amitkumar Karwar <amit.karwar@xxxxxxxxxxxxxxxxxx>
Cc: Fariya Fatima <fariyaf@xxxxxxxxx>
Signed-off-by: Johan Hovold <johan@xxxxxxxxxx>
Signed-off-by: Kalle Valo <kvalo@xxxxxxxxxxxxxx>

diff --git a/drivers/net/wireless/rsi/rsi_91x_usb.c b/drivers/net/wireless/rsi/rsi_91x_usb.c
index 53f41fc2cadf..30bed719486e 100644
--- a/drivers/net/wireless/rsi/rsi_91x_usb.c
+++ b/drivers/net/wireless/rsi/rsi_91x_usb.c
@@ -292,6 +292,15 @@ static void rsi_rx_done_handler(struct urb *urb)
 		dev_kfree_skb(rx_cb->rx_skb);
 }
 
+static void rsi_rx_urb_kill(struct rsi_hw *adapter, u8 ep_num)
+{
+	struct rsi_91x_usbdev *dev = (struct rsi_91x_usbdev *)adapter->rsi_dev;
+	struct rx_usb_ctrl_block *rx_cb = &dev->rx_cb[ep_num - 1];
+	struct urb *urb = rx_cb->rx_urb;
+
+	usb_kill_urb(urb);
+}
+
 /**
  * rsi_rx_urb_submit() - This function submits the given URB to the USB stack.
  * @adapter: Pointer to the adapter structure.
@@ -823,10 +832,13 @@ static int rsi_probe(struct usb_interface *pfunction,
 	if (adapter->priv->coex_mode > 1) {
 		status = rsi_rx_urb_submit(adapter, BT_EP);
 		if (status)
-			goto err1;
+			goto err_kill_wlan_urb;
 	}
 
 	return 0;
+
+err_kill_wlan_urb:
+	rsi_rx_urb_kill(adapter, WLAN_EP);
 err1:
 	rsi_deinit_usb_interface(adapter);
 err:
@@ -857,6 +869,10 @@ static void rsi_disconnect(struct usb_interface *pfunction)
 		adapter->priv->bt_adapter = NULL;
 	}
 
+	if (adapter->priv->coex_mode > 1)
+		rsi_rx_urb_kill(adapter, BT_EP);
+	rsi_rx_urb_kill(adapter, WLAN_EP);
+
 	rsi_reset_card(adapter);
 	rsi_deinit_usb_interface(adapter);
 	rsi_91x_deinit(adapter);