[PATCH 4.7 081/184] iio: ensure ret is initialized to zero before entering do loop

From: Greg Kroah-Hartman
Date: Thu Sep 22 2016 - 13:47:40 EST


4.7-stable review patch. If anyone has any objections, please let me know.

------------------

From: Colin Ian King <colin.king@xxxxxxxxxxxxx>

commit 5dba4b14bafe801083d01e1f400816df7e5a8f2e upstream.

A recent fix to iio_buffer_read_first_n_outer removed ret from being set by
a return from wait_event_interruptible and also added a continue in a loop
which causes the variable ret to not be set when it reaches the end of the
loop. Fix this by initializing ret to zero.

Also remove extraneous white space at the end of the loop.

Fixes: fcf68f3c0bb2a5 ("fix sched WARNING "do not call blocking ops when !TASK_RUNNING")
Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>
Signed-off-by: Jonathan Cameron <jic23@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/iio/industrialio-buffer.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/iio/industrialio-buffer.c
+++ b/drivers/iio/industrialio-buffer.c
@@ -110,7 +110,7 @@ ssize_t iio_buffer_read_first_n_outer(st
DEFINE_WAIT_FUNC(wait, woken_wake_function);
size_t datum_size;
size_t to_wait;
- int ret;
+ int ret = 0;

if (!indio_dev->info)
return -ENODEV;
@@ -153,7 +153,7 @@ ssize_t iio_buffer_read_first_n_outer(st
ret = rb->access->read_first_n(rb, n, buf);
if (ret == 0 && (filp->f_flags & O_NONBLOCK))
ret = -EAGAIN;
- } while (ret == 0);
+ } while (ret == 0);
remove_wait_queue(&rb->pollq, &wait);

return ret;