From: Scott Ellis <scott@jumpnowtek.com>
Date: Mon, 24 May 2010 14:20:27 +0000 (+0000)
Subject: spi/omap2_mcspi: Check params before dereference or use
X-Git-Tag: v2.6.35-rc1~266^2~8
X-Git-Url: http://ftp.safe.ca/?p=safe%2Fjmp%2Flinux-2.6;a=commitdiff_plain;h=99f1a43f436a6a92d15bddfeb65f3a920c8b88d3

spi/omap2_mcspi: Check params before dereference or use

Check spi->chip_select for range before use.

Signed-off-by: Scott Ellis <scott@jumpnowtek.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
---

diff --git a/drivers/spi/omap2_mcspi.c b/drivers/spi/omap2_mcspi.c
index 6df8553..b3a94ca 100644
--- a/drivers/spi/omap2_mcspi.c
+++ b/drivers/spi/omap2_mcspi.c
@@ -834,7 +834,6 @@ 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 */
@@ -844,13 +843,17 @@ 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;
+		}
 	}
 }