diff options
| author | Ian Abbott <abbotti@mev.co.uk> | 2017-03-08 16:02:59 +0000 |
|---|---|---|
| committer | Johan Hovold <johan@kernel.org> | 2017-03-13 16:55:40 +0100 |
| commit | db9240662a44e1b7781c8dbf35631bcec7a369c6 (patch) | |
| tree | b1309bbd05ebb4bcc9288a109d24038243f107c2 /drivers/usb/serial/ftdi_sio.c | |
| parent | 7e1e6ceda3f07a40445ae1c4ac5549a899d5e252 (diff) | |
| download | linux-db9240662a44e1b7781c8dbf35631bcec7a369c6.tar.gz | |
USB: serial: ftdi_sio: only allow valid latency timer values
Valid latency timer values are between 1 ms and 255 ms in 1 ms steps.
The store function for the "latency_timer" device attribute currently
allows any value, although only the lower 16 bits will be sent to the
device, and the device only stores the lower 8 bits. The hardware
appears to accept the (invalid) value 0 and treats it the same as 1
(resulting in a latency of 1 ms).
Change the latency_timer_store() function to accept only the values 0 to
255, returning an error -EINVAL for out-of-range values. Call
kstrtou8() to parse the integer instead of the obsolete
simple_strtoul().
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Johan Hovold <johan@kernel.org>
Diffstat (limited to 'drivers/usb/serial/ftdi_sio.c')
| -rw-r--r-- | drivers/usb/serial/ftdi_sio.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/drivers/usb/serial/ftdi_sio.c b/drivers/usb/serial/ftdi_sio.c index 2b9b5119ff1302..b774f9d32d4f16 100644 --- a/drivers/usb/serial/ftdi_sio.c +++ b/drivers/usb/serial/ftdi_sio.c @@ -1716,9 +1716,12 @@ static ssize_t latency_timer_store(struct device *dev, { struct usb_serial_port *port = to_usb_serial_port(dev); struct ftdi_private *priv = usb_get_serial_port_data(port); - int v = simple_strtoul(valbuf, NULL, 10); + u8 v; int rv; + if (kstrtou8(valbuf, 10, &v)) + return -EINVAL; + priv->latency = v; rv = write_latency_timer(port); if (rv < 0) |