[PATCH 1/3] spi: spi-rockchip: Fix out of bounds array access

[Luis de Arquer <ldearquer@gmail.com>]

From: Luis de Arquer <luis.dearquer@inertim.com>

Since spi-rockchip enables use_gpio_descriptors and the
SPI_CONTROLLER_GPIO_SS flag, the spi subsytem may call set_cs()
for spi devices with indexes above ROCKCHIP_SPI_MAX_CS_NUM

Remove array cs_asserted[] which held a shadow copy of the state
of the chip select lines with the only purpose of optimizing out
rewriting a chip select line to the current state (no-op)
This case is already handled by spi.c

Signed-off-by: Luis de Arquer <luis.dearquer@inertim.com>
---
 drivers/spi/spi-rockchip.c | 8 --------
 1 file changed, 8 deletions(-)

diff --git a/drivers/spi/spi-rockchip.c b/drivers/spi/spi-rockchip.c
index 4b9669da2cf3..2fb2d65bd5f4 100644
--- a/drivers/spi/spi-rockchip.c
+++ b/drivers/spi/spi-rockchip.c
@@ -192,8 +192,6 @@ struct rockchip_spi {
 	u8 n_bytes;
 	u8 rsd;
 
-	bool cs_asserted[ROCKCHIP_SPI_MAX_CS_NUM];
-
 	bool target_abort;
 	bool cs_inactive; /* spi target tansmition stop when cs inactive */
 	bool cs_high_supported; /* native CS supports active-high polarity */
@@ -245,10 +243,6 @@ static void rockchip_spi_set_cs(struct spi_device *spi, bool enable)
 	struct rockchip_spi *rs = spi_controller_get_devdata(ctlr);
 	bool cs_asserted = spi->mode & SPI_CS_HIGH ? enable : !enable;
 
-	/* Return immediately for no-op */
-	if (cs_asserted == rs->cs_asserted[spi_get_chipselect(spi, 0)])
-		return;
-
 	if (cs_asserted) {
 		/* Keep things powered as long as CS is asserted */
 		pm_runtime_get_sync(rs->dev);
@@ -268,8 +262,6 @@ static void rockchip_spi_set_cs(struct spi_device *spi, bool enable)
 		/* Drop reference from when we first asserted CS */
 		pm_runtime_put(rs->dev);
 	}
-
-	rs->cs_asserted[spi_get_chipselect(spi, 0)] = cs_asserted;
 }
 
 static void rockchip_spi_handle_err(struct spi_controller *ctlr,
-- 
2.34.1



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