staging: comedi: comedi_fops: remove BUG_ON() in comedi_free_subdevice_minor()

Drivers should not crash the kernel.

This function is only called by comedi_device_detach_cleanup() and the
s->minor will always be valid or the device wouldn't have attached in
the first place.

Leave the checks for safety in accessing the comedi_subdevice_minor_table
array but remove the BUG_ON() calls.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/comedi/comedi_fops.c b/drivers/staging/comedi/comedi_fops.c
index 93b37e2..2e69f5a 100644 (file)
--- a/drivers/staging/comedi/comedi_fops.c
+++ b/drivers/staging/comedi/comedi_fops.c
@@ -2836,12 +2836,10 @@ void comedi_free_subdevice_minor(struct comedi_subdevice *s)
 
        if (!s)
                return;
-       if (s->minor < 0)
+       if (s->minor < COMEDI_NUM_BOARD_MINORS ||
+           s->minor >= COMEDI_NUM_MINORS)
                return;
 
-       BUG_ON(s->minor >= COMEDI_NUM_MINORS);
-       BUG_ON(s->minor < COMEDI_NUM_BOARD_MINORS);
-
        i = s->minor - COMEDI_NUM_BOARD_MINORS;
        mutex_lock(&comedi_subdevice_minor_table_lock);
        if (s == comedi_subdevice_minor_table[i])