On Mon, Sep 25, 2023 at 11:40 AM CK Hu (胡俊光) <ck.hu@xxxxxxxxxxxx> wrote:
Hi, Hubert:
On Mon, 2023-09-25 at 09:22 +0000, Hubert Mazur wrote:
>
> External email : Please do not click links or open attachments until
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> The buffer size is derived from parameters supplied by the
> userspace.
> Having the size equal 0 causes allocation failure leading to kernel
> panic.
The size is calculated by width and height, and drm_mode_create_dumb()
has checked the width and height, so the size would not be 0. So this
patch is redundant.
Ah, you are right, I had an inner checkout which required this fix.
Let's abandon this patch.
Thanks for the review!
Regards,
Hubert
Regards,
CK
>
> Fix this by checking if size equals 0.
>
> Fixes: 119f5173628a ("drm/mediatek: Add DRM Driver for Mediatek SoC
> MT8173.")
>
> Signed-off-by: Hubert Mazur <hmazur@xxxxxxxxxxxx>
> ---
> drivers/gpu/drm/mediatek/mtk_drm_gem.c | 5 +++++
> 1 file changed, 5 insertions(+)
>
> diff --git a/drivers/gpu/drm/mediatek/mtk_drm_gem.c
> b/drivers/gpu/drm/mediatek/mtk_drm_gem.c
> index 9f364df52478..3b985b99d5c6 100644
> --- a/drivers/gpu/drm/mediatek/mtk_drm_gem.c
> +++ b/drivers/gpu/drm/mediatek/mtk_drm_gem.c
> @@ -62,6 +62,11 @@ struct mtk_drm_gem_obj *mtk_drm_gem_create(struct
> drm_device *dev,
> struct drm_gem_object *obj;
> int ret;
>
> + if (size == 0) {
> + DRM_ERROR("Invalid allocation size: %zu", size);
> + return ERR_PTR(-EINVAL);
> + }
> +
> mtk_gem = mtk_drm_gem_init(dev, size);
> if (IS_ERR(mtk_gem))
> return ERR_CAST(mtk_gem);
> --
> 2.42.0.515.g380fc7ccd1-goog
