From: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
From: Ian Abbott <abbotti@xxxxxxxxx>
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@xxxxxxxxxxxxxxx> # 4.0+
Signed-off-by: Ian Abbott <abbotti@xxxxxxxxx>
Link: https://lore.kernel.org/r/20210223143055.257402-10-abbotti@xxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
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
@@ -422,7 +422,7 @@ 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;
