Re: [v1] gpu: drm: sti: sti_vtg:- Handle return NULL error from devm_ioremap_nocache

From: Vincent ABRIOU
Date: Wed Jan 04 2017 - 05:22:56 EST


Thanks for the patch.

Acked-by: Vincent Abriou <vincent.abriou@xxxxxx>

I will take it for pull request that should be issued by the end of the
week.

Vincent

On 12/21/2016 06:30 AM, Arvind Yadav wrote:
> Here, If devm_ioremap_nocache will fail. It will return NULL.
> Kernel can run into a NULL-pointer dereference. This error check
> will avoid NULL pointer dereference.
>
> Signed-off-by: Arvind Yadav <arvind.yadav.cs@xxxxxxxxx>
> ---
> drivers/gpu/drm/sti/sti_vtg.c | 4 ++++
> 1 file changed, 4 insertions(+)
>
> diff --git a/drivers/gpu/drm/sti/sti_vtg.c b/drivers/gpu/drm/sti/sti_vtg.c
> index a8882bd..c3d9c8a 100644
> --- a/drivers/gpu/drm/sti/sti_vtg.c
> +++ b/drivers/gpu/drm/sti/sti_vtg.c
> @@ -429,6 +429,10 @@ static int vtg_probe(struct platform_device *pdev)
> return -ENOMEM;
> }
> vtg->regs = devm_ioremap_nocache(dev, res->start, resource_size(res));
> + if (!vtg->regs) {
> + DRM_ERROR("failed to remap I/O memory\n");
> + return -ENOMEM;
> + }
>
> np = of_parse_phandle(pdev->dev.of_node, "st,slave", 0);
> if (np) {
>