[PATCH 1/4] mtd: mxc_nand: avoid NULL pointer dereference

From: Alexander Beregalov
Date: Wed Jan 06 2010 - 20:48:59 EST


Assign nand_chip and host only if host is not NULL.

Cc: David Woodhouse <dwmw2@xxxxxxxxxxxxx>
Signed-off-by: Alexander Beregalov <a.beregalov@xxxxxxxxx>
---
drivers/mtd/nand/mxc_nand.c | 12 ++++++++----
1 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/drivers/mtd/nand/mxc_nand.c b/drivers/mtd/nand/mxc_nand.c
index 45dec57..4ace54c 100644
--- a/drivers/mtd/nand/mxc_nand.c
+++ b/drivers/mtd/nand/mxc_nand.c
@@ -881,12 +881,14 @@ static int __devexit mxcnd_remove(struct platform_device *pdev)
static int mxcnd_suspend(struct platform_device *pdev, pm_message_t state)
{
struct mtd_info *mtd = platform_get_drvdata(pdev);
- struct nand_chip *nand_chip = mtd->priv;
- struct mxc_nand_host *host = nand_chip->priv;
+ struct nand_chip *nand_chip;
+ struct mxc_nand_host *host;
int ret = 0;

DEBUG(MTD_DEBUG_LEVEL0, "MXC_ND : NAND suspend\n");
if (mtd) {
+ nand_chip = mtd->priv;
+ host = nand_chip->priv;
ret = mtd->suspend(mtd);
/* Disable the NFC clock */
clk_disable(host->clk);
@@ -898,13 +900,15 @@ static int mxcnd_suspend(struct platform_device *pdev, pm_message_t state)
static int mxcnd_resume(struct platform_device *pdev)
{
struct mtd_info *mtd = platform_get_drvdata(pdev);
- struct nand_chip *nand_chip = mtd->priv;
- struct mxc_nand_host *host = nand_chip->priv;
+ struct nand_chip *nand_chip;
+ struct mxc_nand_host *host;
int ret = 0;

DEBUG(MTD_DEBUG_LEVEL0, "MXC_ND : NAND resume\n");

if (mtd) {
+ nand_chip = mtd->priv;
+ host = nand_chip->priv;
/* Enable the NFC clock */
clk_enable(host->clk);
mtd->resume(mtd);
--
1.6.6

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/