comedi: dt2811: Add sanity checks for I/O base address

The "dt2811" driver uses an admin-supplied configuration option
(`it->options[0]`) to configure the I/O port base address of a supported
board in the DT2811 family.  It currently allows any base address to be
configured but the hardware only supports base addresses (configured by
on-board jumpers) in the range 0x200 to 0x3f8 on 8-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/20260130170416.49994-21-abbotti@mev.co.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/comedi/drivers/dt2811.c b/drivers/comedi/drivers/dt2811.c
index dbb9f38da2898c18057f514c4d312b35faeac39d..bcc4b5ef48e8db2fb8077cebdbecbb280eeb36bc 100644 (file)
--- a/drivers/comedi/drivers/dt2811.c
+++ b/drivers/comedi/drivers/dt2811.c
@@ -556,7 +556,8 @@ static int dt2811_attach(struct comedi_device *dev, struct comedi_devconfig *it)
        if (!devpriv)
                return -ENOMEM;
 
-       ret = comedi_request_region(dev, it->options[0], 0x8);
+       ret = comedi_check_request_region(dev, it->options[0], 0x8,
+                                         0x200, 0x3ff, 8);
        if (ret)
                return ret;