From 8536749d4952649ada4a88396079e6ec69c1fc9f Mon Sep 17 00:00:00 2001 From: Ian Abbott Date: Tue, 23 Feb 2021 14:30:51 +0000 Subject: staging: comedi: amplc_pc236_common: Use 16-bit 0 for interrupt data The Amplicon PC36AT/PCI236 common 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/20210223143055.257402-11-abbotti@mev.co.uk Signed-off-by: Greg Kroah-Hartman --- drivers/staging/comedi/drivers/amplc_pc236_common.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'drivers/staging') diff --git a/drivers/staging/comedi/drivers/amplc_pc236_common.c b/drivers/staging/comedi/drivers/amplc_pc236_common.c index 043752663188..981d281e87a1 100644 --- a/drivers/staging/comedi/drivers/amplc_pc236_common.c +++ b/drivers/staging/comedi/drivers/amplc_pc236_common.c @@ -126,7 +126,9 @@ static irqreturn_t pc236_interrupt(int irq, void *d) handled = pc236_intr_check(dev); if (dev->attached && handled) { - comedi_buf_write_samples(s, &s->state, 1); + unsigned short val = 0; + + comedi_buf_write_samples(s, &val, 1); comedi_handle_events(dev, s); } return IRQ_RETVAL(handled); -- cgit