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From 4d6636498c41891d0482a914dd570343a838ad79 Mon Sep 17 00:00:00 2001
From: Johan Hovold <johan@kernel.org>
Date: Tue, 1 Oct 2019 12:29:13 +0200
Subject: [PATCH] can: mcba_usb: fix use-after-free on disconnect
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Git-commit: 4d6636498c41891d0482a914dd570343a838ad79
Patch-mainline: v5.4-rc7
References: CVE-2019-19529 bsc#1158381

The driver was accessing its driver data after having freed it.

Fixes: 51f3baad7de9 ("can: mcba_usb: Add support for Microchip CAN BUS Analyzer")
Cc: stable <stable@vger.kernel.org>     # 4.12
Cc: Remigiusz Kołłątaj <remigiusz.kollataj@mobica.com>
Reported-by: syzbot+e29b17e5042bbc56fae9@syzkaller.appspotmail.com
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/net/can/usb/mcba_usb.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/net/can/usb/mcba_usb.c b/drivers/net/can/usb/mcba_usb.c
index 19a702ac49e4..21faa2ec4632 100644
--- a/drivers/net/can/usb/mcba_usb.c
+++ b/drivers/net/can/usb/mcba_usb.c
@@ -876,9 +876,8 @@ static void mcba_usb_disconnect(struct usb_interface *intf)
 	netdev_info(priv->netdev, "device disconnected\n");
 
 	unregister_candev(priv->netdev);
-	free_candev(priv->netdev);
-
 	mcba_urb_unlink(priv);
+	free_candev(priv->netdev);
 }
 
 static struct usb_driver mcba_usb_driver = {
-- 
2.16.4