From 435dd557b0e93e7fb9383adcb72f7423d26af45d Mon Sep 17 00:00:00 2001 From: Ian Abbott Date: Tue, 23 Feb 2021 14:30:50 +0000 Subject: [PATCH] staging: comedi: pcl818: Fix endian problem for AI command data BugLink: https://bugs.launchpad.net/bugs/1919492 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: # 4.0+ Signed-off-by: Ian Abbott Link: https://lore.kernel.org/r/20210223143055.257402-10-abbotti@mev.co.uk Signed-off-by: Greg Kroah-Hartman Signed-off-by: Seth Forshee --- drivers/staging/comedi/drivers/pcl818.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/staging/comedi/drivers/pcl818.c b/drivers/staging/comedi/drivers/pcl818.c index 63e3011158f2..f4b4a686c710 100644 --- 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_device *dev, 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; -- 2.39.2