[PATCH v3 05/20] iio: introduced iio_push_to_buffers_with_ts() that takes a data_total_len argument.

[Jonathan Cameron <jic23@kernel.org>]

From: Jonathan Cameron <Jonathan.Cameron@huawei.com>

Check that data_total_len argument against iio_dev->scan_bytes.

The size needs to be at least as big as the scan. It can be larger,
which is typical if only part of fixed sized storage is used due to
a subset of channels being enabled.

Reviewed-by: Nuno Sá <nuno.sa@analog.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
---
v3:
- Use an s64 instead of int64_t for the new function (Andy)

v2:
- Rename size to data_total_len to make it clear that it is about
  data but also that it isn't simply the length to be used.
- Added an unlikely marking.
---
 include/linux/iio/buffer.h | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/include/linux/iio/buffer.h b/include/linux/iio/buffer.h
index 3b8d618bb3df..5c84ec4a9810 100644
--- a/include/linux/iio/buffer.h
+++ b/include/linux/iio/buffer.h
@@ -45,6 +45,18 @@ static inline int iio_push_to_buffers_with_timestamp(struct iio_dev *indio_dev,
 	return iio_push_to_buffers(indio_dev, data);
 }
 
+static inline int iio_push_to_buffers_with_ts(struct iio_dev *indio_dev,
+					      void *data, size_t data_total_len,
+					      s64 timestamp)
+{
+	if (unlikely(data_total_len < indio_dev->scan_bytes)) {
+		dev_err(&indio_dev->dev, "Undersized storage pushed to buffer\n");
+		return -ENOSPC;
+	}
+
+	return iio_push_to_buffers_with_timestamp(indio_dev, data, timestamp);
+}
+
 int iio_push_to_buffers_with_ts_unaligned(struct iio_dev *indio_dev,
 					  const void *data, size_t data_sz,
 					  int64_t timestamp);
-- 
2.49.0