spi/xilinx: Fix access invalid memory on xilinx_spi_tx
On 1 and 2 bytes per word, the transfer of the 3 last bytes will access
memory outside tx_ptr.
Although this has not trigger any error on real hardware, we should
better fix this.
Fixes: 24ba5e593f391507 (Remove rx_fn and tx_fn pointer)
Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
diff --git a/drivers/spi/spi-xilinx.c b/drivers/spi/spi-xilinx.c
index d1901d5..133f53a 100644
--- a/drivers/spi/spi-xilinx.c
+++ b/drivers/spi/spi-xilinx.c
@@ -117,11 +117,26 @@
static void xilinx_spi_tx(struct xilinx_spi *xspi)
{
+ u32 data = 0;
+
if (!xspi->tx_ptr) {
xspi->write_fn(0, xspi->regs + XSPI_TXD_OFFSET);
return;
}
- xspi->write_fn(*(u32 *)(xspi->tx_ptr), xspi->regs + XSPI_TXD_OFFSET);
+
+ switch (xspi->bytes_per_word) {
+ case 1:
+ data = *(u8 *)(xspi->tx_ptr);
+ break;
+ case 2:
+ data = *(u16 *)(xspi->tx_ptr);
+ break;
+ case 4:
+ data = *(u32 *)(xspi->tx_ptr);
+ break;
+ }
+
+ xspi->write_fn(data, xspi->regs + XSPI_TXD_OFFSET);
xspi->tx_ptr += xspi->bytes_per_word;
}