spi: core: Validate length of the transfers in message
SPI transfer length should be multiple of SPI word size,
where SPI word size should be power-of-two multiple
Signed-off-by: Ivan T. Ivanov <iivanov@mm-sol.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index bb66014..1b53eee 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -1617,6 +1617,7 @@
{
struct spi_master *master = spi->master;
struct spi_transfer *xfer;
+ int w_size, n_words;
if (list_empty(&message->transfers))
return -EINVAL;
@@ -1668,6 +1669,22 @@
return -EINVAL;
}
+ /*
+ * SPI transfer length should be multiple of SPI word size
+ * where SPI word size should be power-of-two multiple
+ */
+ if (xfer->bits_per_word <= 8)
+ w_size = 1;
+ else if (xfer->bits_per_word <= 16)
+ w_size = 2;
+ else
+ w_size = 4;
+
+ n_words = xfer->len / w_size;
+ /* No partial transfers accepted */
+ if (!n_words || xfer->len % w_size)
+ return -EINVAL;
+
if (xfer->speed_hz && master->min_speed_hz &&
xfer->speed_hz < master->min_speed_hz)
return -EINVAL;