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

The "ni_at_ao" driver uses an admin-supplied configuration option
(`it->options[0]`) to configure the I/O port base address of an AT-AO-6
or AT-AO-10 board.  It currently allows any base address to be
configured but the hardware only supports base addresses (configured by
on-board jumpers) in the range 0 to 0x3E0 on 32-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/20260130170416.49994-29-abbotti@mev.co.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/comedi/drivers/ni_at_ao.c b/drivers/comedi/drivers/ni_at_ao.c
index 9cf6b4ff6b653560e775428901db05174d73cc6d..31fd64bf82062b22894112357efc7b1503168934 100644 (file)
--- a/drivers/comedi/drivers/ni_at_ao.c
+++ b/drivers/comedi/drivers/ni_at_ao.c
@@ -295,7 +295,8 @@ static int atao_attach(struct comedi_device *dev, struct comedi_devconfig *it)
        struct comedi_subdevice *s;
        int ret;
 
-       ret = comedi_request_region(dev, it->options[0], 0x20);
+       ret = comedi_check_request_region(dev, it->options[0], 0x20,
+                                         0, 0x3ff, 32);
        if (ret)
                return ret;