From: Greg Kroah-Hartman gregkh@linuxfoundation.org
From: Ian Abbott abbotti@mev.co.uk
commit 148e34fd33d53740642db523724226de14ee5281 upstream.
The analog input subdevice supports Comedi asynchronous commands that use Comedi's 16-bit sample format. However, the call to `comedi_buf_write_samples()` is passing the address of a 32-bit integer parameter. On bigendian machines, this will copy 2 bytes from the wrong end of the 32-bit value. Fix it by changing the type of the parameter holding the sample value to `unsigned short`.
[Note: the bug was introduced in commit edf4537bcbf5 ("staging: comedi: pcl818: use comedi_buf_write_samples()") but the patch applies better to commit d615416de615 ("staging: comedi: pcl818: introduce pcl818_ai_write_sample()").]
Fixes: d615416de615 ("staging: comedi: pcl818: introduce pcl818_ai_write_sample()") Cc: stable@vger.kernel.org # 4.0+ Signed-off-by: Ian Abbott abbotti@mev.co.uk Link: https://lore.kernel.org/r/20210223143055.257402-10-abbotti@mev.co.uk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/staging/comedi/drivers/pcl818.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/staging/comedi/drivers/pcl818.c +++ b/drivers/staging/comedi/drivers/pcl818.c @@ -423,7 +423,7 @@ static int pcl818_ai_eoc(struct comedi_d
static bool pcl818_ai_write_sample(struct comedi_device *dev, struct comedi_subdevice *s, - unsigned int chan, unsigned int val) + unsigned int chan, unsigned short val) { struct pcl818_private *devpriv = dev->private; struct comedi_cmd *cmd = &s->async->cmd;