comedi: s526: Add sanity checks for I/O base address

The "s526" driver uses an admin-supplied configuration option
(`it->options[0]`) to configure the I/O port base address of a Sensoray
526 board.  It currently allows any base address to be configured but
the hardware only supports base addresses (configured by on-board DIP
switches) in the range 0 to 0xFFC0 on 64-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/20260130170416.49994-47-abbotti@mev.co.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/comedi/drivers/s526.c b/drivers/comedi/drivers/s526.c
index 9245c679a3c4476673554d37c0cecc6dea1bbff6..dd27c754dea45f504bd7ba400fc6f6f729d24c96 100644 (file)
--- a/drivers/comedi/drivers/s526.c
+++ b/drivers/comedi/drivers/s526.c
@@ -553,7 +553,8 @@ static int s526_attach(struct comedi_device *dev, struct comedi_devconfig *it)
        struct comedi_subdevice *s;
        int ret;
 
-       ret = comedi_request_region(dev, it->options[0], 0x40);
+       ret = comedi_check_request_region(dev, it->options[0], 0x40,
+                                         0, 0xffc0, 64);
        if (ret)
                return ret;