syzbot report in rsi_91x_usb.c

[Julia Lawall <julia.lawall@lip6.fr>]

Hello,

I spent some time looking at:

https://syzkaller.appspot.com/bug?id=c1b6aa968706d9380dcdb98a9f2c338071cc938c

which does not yet report that it has been fixed.

The problem seems to be in rsi_probe in
drivers/net/wireless/rsi/rsi_91x_usb.c.  This ends with the following
code:

        status = rsi_rx_urb_submit(adapter, WLAN_EP);
        if (status)
                goto err1;

        if (adapter->priv->coex_mode > 1) {
                status = rsi_rx_urb_submit(adapter, BT_EP);
                if (status)
                        goto err1;
        }

        return 0;
err1:
        rsi_deinit_usb_interface(adapter);
err:
        rsi_91x_deinit(adapter);


The problem seems to be that the first call to rsi_rx_urb_submit succeeds,
submitting an urb, and then theh second one fails.  Both share adapter,
which is used in rsi_rx_done_handler, invoked later as the callback
provided with usb_submit_urb.  But adapter, and in particular its rsi_dev
field, are freed by the rsi_91x_deinit call due to the failure of the
second call to rsi_rx_urb_submit.

How should this be fixed?

thanks,
julia