From fd3ce6557da0e7557a451ee56fc8f5700d3bd08f Mon Sep 17 00:00:00 2001 From: Ian Abbott Date: Tue, 23 Feb 2021 14:30:55 +0000 Subject: [PATCH] staging: comedi: pcl726: Use 16-bit 0 for interrupt data The pcl726 driver has an "interrupt" subdevice that supports Comedi asynchronous commands, placing a value in the Comedi buffer for each interrupt. The subdevice uses Comedi's 16-bit sample format but the interrupt handler is calling `comedi_buf_write_samples()` with the address of a 32-bit integer `&s->state`. On bigendian machines, this will copy 2 bytes from the wrong end of the 32-bit integer. This isn't really a problem since `s->state` will always be 0 for this subdevice, but clean it up by using a 16-bit variable initialized to 0 to pass the value. Signed-off-by: Ian Abbott Link: https://lore.kernel.org/r/20210223143055.257402-15-abbotti@mev.co.uk Signed-off-by: Greg Kroah-Hartman --- drivers/staging/comedi/drivers/pcl726.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/staging/comedi/drivers/pcl726.c b/drivers/staging/comedi/drivers/pcl726.c index 64eb649..88f25d7 100644 --- a/drivers/staging/comedi/drivers/pcl726.c +++ b/drivers/staging/comedi/drivers/pcl726.c @@ -220,9 +220,11 @@ static irqreturn_t pcl726_interrupt(int irq, void *d) struct pcl726_private *devpriv = dev->private; if (devpriv->cmd_running) { + unsigned short val = 0; + pcl726_intr_cancel(dev, s); - comedi_buf_write_samples(s, &s->state, 1); + comedi_buf_write_samples(s, &val, 1); comedi_handle_events(dev, s); } -- 2.7.4