2017-07-07 06:11:29

by Gustavo A. R. Silva

[permalink] [raw]
Subject: [PATCH] drm/tegra: sor: add NULL check on of_match_device() return value

Check return value from call to of_match_device()
in order to prevent a NULL pointer dereference.

In case of NULL print error message and return.

Signed-off-by: Gustavo A. R. Silva <[email protected]>
---
drivers/gpu/drm/tegra/sor.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/drivers/gpu/drm/tegra/sor.c b/drivers/gpu/drm/tegra/sor.c
index a8f5289..ca3d9b1 100644
--- a/drivers/gpu/drm/tegra/sor.c
+++ b/drivers/gpu/drm/tegra/sor.c
@@ -2538,6 +2538,10 @@ static int tegra_sor_probe(struct platform_device *pdev)
int err;

match = of_match_device(tegra_sor_of_match, &pdev->dev);
+ if (!match) {
+ dev_err(&pdev->dev, "failed to match device\n");
+ return -ENODEV;
+ }

sor = devm_kzalloc(&pdev->dev, sizeof(*sor), GFP_KERNEL);
if (!sor)
--
2.5.0


2017-07-07 07:42:17

by Jon Hunter

[permalink] [raw]
Subject: Re: [PATCH] drm/tegra: sor: add NULL check on of_match_device() return value


On 07/07/17 07:11, Gustavo A. R. Silva wrote:
> Check return value from call to of_match_device()
> in order to prevent a NULL pointer dereference.
>
> In case of NULL print error message and return.
>
> Signed-off-by: Gustavo A. R. Silva <[email protected]>
> ---
> drivers/gpu/drm/tegra/sor.c | 4 ++++
> 1 file changed, 4 insertions(+)
>
> diff --git a/drivers/gpu/drm/tegra/sor.c b/drivers/gpu/drm/tegra/sor.c
> index a8f5289..ca3d9b1 100644
> --- a/drivers/gpu/drm/tegra/sor.c
> +++ b/drivers/gpu/drm/tegra/sor.c
> @@ -2538,6 +2538,10 @@ static int tegra_sor_probe(struct platform_device *pdev)
> int err;
>
> match = of_match_device(tegra_sor_of_match, &pdev->dev);
> + if (!match) {
> + dev_err(&pdev->dev, "failed to match device\n");
> + return -ENODEV;
> + }

Given that Tegra always uses device-tree, I believe that this cannot
happen and so this additional check is not needed.

Jon

--
nvpublic