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 variable. 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 variable holding the sample value to `unsigned short`.
[Note: the bug was introduced in commit 1700529b24cc ("staging: comedi: dmm32at: use comedi_buf_write_samples()") but the patch applies better to the later (but in the same kernel release) commit 0c0eadadcbe6e ("staging: comedi: dmm32at: introduce dmm32_ai_get_sample()").]
Fixes: 0c0eadadcbe6e ("staging: comedi: dmm32at: introduce dmm32_ai_get_sample()") Cc: stable@vger.kernel.org # 3.19+ Signed-off-by: Ian Abbott abbotti@mev.co.uk --- drivers/staging/comedi/drivers/dmm32at.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/staging/comedi/drivers/dmm32at.c b/drivers/staging/comedi/drivers/dmm32at.c index 17e6018918bb..56682f01242f 100644 --- a/drivers/staging/comedi/drivers/dmm32at.c +++ b/drivers/staging/comedi/drivers/dmm32at.c @@ -404,7 +404,7 @@ static irqreturn_t dmm32at_isr(int irq, void *d) { struct comedi_device *dev = d; unsigned char intstat; - unsigned int val; + unsigned short val; int i;
if (!dev->attached) {