4.4-stable review patch. If anyone has any objections, please let me know.
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From: Jia-Ju Bai baijiaju1990@gmail.com
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: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Johan Hovold johan@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/usb/serial/io_edgeport.c | 1 - 1 file changed, 1 deletion(-)
--- a/drivers/usb/serial/io_edgeport.c +++ b/drivers/usb/serial/io_edgeport.c @@ -2219,7 +2219,6 @@ static int write_cmd_usb(struct edgeport /* 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;