comedi: pcl816: Add sanity checks for I/O base address

The "pcl816" driver uses an admin-supplied configuration option
(`it->options[0]`) to configure the I/O port base address of a PCL-816
or PCL-814B ISA board.  It currently allows any base address to be
configured but the hardware devices only support base addresses
(configured by on-board DIP switches) from 0 to 0x3F0 on 16-byte
boundaries.

Add a sanity check to ensure the device is not configured at an
unsupported base address.

Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Link: https://patch.msgid.link/20260130170416.49994-38-abbotti@mev.co.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/comedi/drivers/pcl816.c b/drivers/comedi/drivers/pcl816.c
index 28d1a88c50f6531bebc16189ddffdf60e8b4a2d2..1fcb2f798c7a58a2174c825a860bd015007695c1 100644 (file)
--- a/drivers/comedi/drivers/pcl816.c
+++ b/drivers/comedi/drivers/pcl816.c
@@ -608,7 +608,8 @@ static int pcl816_attach(struct comedi_device *dev, struct comedi_devconfig *it)
        if (!devpriv)
                return -ENOMEM;
 
-       ret = comedi_request_region(dev, it->options[0], 0x10);
+       ret = comedi_check_request_region(dev, it->options[0], 0x10,
+                                         0, 0x3ff, 16);
        if (ret)
                return ret;