USB: serial: io_edgeport: fix possible sleep-in-atomic

commit c7b8f77872c73f69a16528a9eb87afefcccdc18b upstream.

According to drivers/usb/serial/io_edgeport.c, the driver may sleep
under a spinlock.
The function call path is:
edge_bulk_in_callback (acquire the spinlock)
   process_rcvd_data
     process_rcvd_status
       change_port_settings
         send_iosp_ext_cmd
           write_cmd_usb
             usb_kill_urb --> may sleep

To fix it, the redundant usb_kill_urb() is removed from the error path
after usb_submit_urb() fails.

This possible bug is found by my static analysis tool (DSAC) and checked
by my code review.

Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Jia-Ju Bai 2017-12-13 20:34:36 +08:00 committed by Greg Kroah-Hartman
parent aaea9d3f6c
commit 95bb041eef

View file

@ -2219,7 +2219,6 @@ static int write_cmd_usb(struct edgeport_port *edge_port,
/* something went wrong */
dev_err(dev, "%s - usb_submit_urb(write command) failed, status = %d\n",
__func__, status);
usb_kill_urb(urb);
usb_free_urb(urb);
atomic_dec(&CmdUrbs);
return status;