Re: [PATCHv3 1/6] SPI omap2_mcspi.c: Check params before dereference or use

[Scott Ellis <scott-oZqG5KApg2M/jFmSBShxMA@public.gmane.org>]

Check spi->chip_select for range before use.

The spi->controller_state check is already in 2.6.34-rc7

Signed-off-by: Scott Ellis <scott-oZqG5KApg2M/jFmSBShxMA@public.gmane.org>

 drivers/spi/omap2_mcspi.c |   19 +++++++++++--------
 1 files changed, 11 insertions(+), 8 deletions(-)

diff --git a/drivers/spi/omap2_mcspi.c b/drivers/spi/omap2_mcspi.c
index e0de0d0..0b35468 100644
--- a/drivers/spi/omap2_mcspi.c
+++ b/drivers/spi/omap2_mcspi.c
@@ -755,7 +755,6 @@ static void omap2_mcspi_cleanup(struct spi_device
*spi)
 	struct omap2_mcspi_cs	*cs;
 
 	mcspi = spi_master_get_devdata(spi->master);
-	mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 
 	if (spi->controller_state) {
 		/* Unlink controller state from context save list */
@@ -765,13 +764,17 @@ static void omap2_mcspi_cleanup(struct spi_device
*spi)
 		kfree(spi->controller_state);
 	}
 
-	if (mcspi_dma->dma_rx_channel != -1) {
-		omap_free_dma(mcspi_dma->dma_rx_channel);
-		mcspi_dma->dma_rx_channel = -1;
-	}
-	if (mcspi_dma->dma_tx_channel != -1) {
-		omap_free_dma(mcspi_dma->dma_tx_channel);
-		mcspi_dma->dma_tx_channel = -1;
+	if (spi->chip_select < spi->master->num_chipselect) {
+		mcspi_dma = &mcspi->dma_channels[spi->chip_select];
+
+		if (mcspi_dma->dma_rx_channel != -1) {
+			omap_free_dma(mcspi_dma->dma_rx_channel);
+			mcspi_dma->dma_rx_channel = -1;
+		}
+		if (mcspi_dma->dma_tx_channel != -1) {
+			omap_free_dma(mcspi_dma->dma_tx_channel);
+			mcspi_dma->dma_tx_channel = -1;
+		}
 	}
 }


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