comedi: amplc_pc236: Add sanity checks for I/O base address

The "amplc_pc236" driver uses an admin-supplied configuration option
(`it->options[0]`) to configure the I/O port base address of a supported
PC36AT board.  It currently allows any base address to be configured but
the hardware only supports base addresses (set by on-board DIP switches)
in the range 0 to 0xFFC on 4-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/20260130170416.49994-8-abbotti@mev.co.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/comedi/drivers/amplc_pc236.c b/drivers/comedi/drivers/amplc_pc236.c
index b21e0c906aab6d6a596317d079a9b85d2ee19a16..eadee10983bfb22f8d9c0b2dea5b5dc9a66f7140 100644 (file)
--- a/drivers/comedi/drivers/amplc_pc236.c
+++ b/drivers/comedi/drivers/amplc_pc236.c
@@ -45,7 +45,8 @@ static int pc236_attach(struct comedi_device *dev, struct comedi_devconfig *it)
        if (!devpriv)
                return -ENOMEM;
 
-       ret = comedi_request_region(dev, it->options[0], 0x4);
+       ret = comedi_check_request_region(dev, it->options[0], 0x4,
+                                         0, 0xfff, 4);
        if (ret)
                return ret;