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

The "pcmad" driver uses an admin-supplied configuration option
(`it->options[0]`) to configure the I/O port base address of a
PCM-A/D-12 or PCM-A/D-16 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 0x3FC 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/20260130170416.49994-41-abbotti@mev.co.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/comedi/drivers/pcmad.c b/drivers/comedi/drivers/pcmad.c
index 976eda43881bc57d024cf98a8619b0b5cde063e7..fd26b1eed1dbb5bbfc84966d379f2f68c2456e95 100644 (file)
--- a/drivers/comedi/drivers/pcmad.c
+++ b/drivers/comedi/drivers/pcmad.c
@@ -106,7 +106,8 @@ static int pcmad_attach(struct comedi_device *dev, struct comedi_devconfig *it)
        struct comedi_subdevice *s;
        int ret;
 
-       ret = comedi_request_region(dev, it->options[0], 0x04);
+       ret = comedi_check_request_region(dev, it->options[0], 0x04,
+                                         0, 0x3ff, 4);
        if (ret)
                return ret;