[PATCH] dmaengine: img-mdc: fix a possible NULL dereference

[PATCH] dmaengine: img-mdc: fix a possible NULL dereference

[LABBE Corentin]

of_match_device could return NULL, and so cause a NULL pointer
dereference later at line 850:
mdma->soc = match->data;

For fixing this problem, we use of_device_get_match_data(), this will
simplify the code a little by using a standard function for
getting the match data.

Reported-by: coverity (CID 1324134)
Signed-off-by: LABBE Corentin <clabbe.montjoie@gmail.com>
---
 drivers/dma/img-mdc-dma.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/drivers/dma/img-mdc-dma.c b/drivers/dma/img-mdc-dma.c
index a4c53be..624f1e1 100644
--- a/drivers/dma/img-mdc-dma.c
+++ b/drivers/dma/img-mdc-dma.c
@@ -861,7 +861,6 @@ static int mdc_dma_probe(struct platform_device *pdev)
 {
 	struct mdc_dma *mdma;
 	struct resource *res;
-	const struct of_device_id *match;
 	unsigned int i;
 	u32 val;
 	int ret;
@@ -871,8 +870,7 @@ static int mdc_dma_probe(struct platform_device *pdev)
 		return -ENOMEM;
 	platform_set_drvdata(pdev, mdma);
 
-	match = of_match_device(mdc_dma_of_match, &pdev->dev);
-	mdma->soc = match->data;
+	mdma->soc = of_device_get_match_data(&pdev->dev);
 
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	mdma->regs = devm_ioremap_resource(&pdev->dev, res);
-- 
2.7.3

Re: [PATCH] dmaengine: img-mdc: fix a possible NULL dereference

[Vinod Koul]

On Tue, Aug 16, 2016 at 10:44:18AM +0200, LABBE Corentin wrote:
> of_match_device could return NULL, and so cause a NULL pointer
> dereference later at line 850:
> mdma->soc = match->data;
> 
> For fixing this problem, we use of_device_get_match_data(), this will
> simplify the code a little by using a standard function for
> getting the match data.
> 
> Reported-by: coverity (CID 1324134)

The reported-by tags expects an email ID. I have modfied this to freetext
and applied
-- 
~Vinod