On Wed, 22 May 2019, Gen Zhang <blackgod016...@gmail.com> wrote:
> In drm_load_edid_firmware(), fwstr is allocated by kstrdup(). And fwstr
> is dereferenced in the following codes. However, memory allocation 
> functions such as kstrdup() may fail and returns NULL. Dereferencing 
> this null pointer may cause the kernel go wrong. Thus we should check 
> this kstrdup() operation.
> Further, if kstrdup() returns NULL, we should return ERR_PTR(-ENOMEM) to
> the caller site.

strsep() handles the NULL pointer just fine, so there won't be a NULL
dereference. However this patch seems like the right thing to do anyway.

Reviewed-by: Jani Nikula <jani.nik...@intel.com>

>
> Signed-off-by: Gen Zhang <blackgod016...@gmail.com>
>
> ---
> diff --git a/drivers/gpu/drm/drm_edid_load.c b/drivers/gpu/drm/drm_edid_load.c
> index a491509..a0e107a 100644
> --- a/drivers/gpu/drm/drm_edid_load.c
> +++ b/drivers/gpu/drm/drm_edid_load.c
> @@ -290,6 +290,8 @@ struct edid *drm_load_edid_firmware(struct drm_connector 
> *connector)
>        * the last one found one as a fallback.
>        */
>       fwstr = kstrdup(edid_firmware, GFP_KERNEL);
> +     if (!fwstr)
> +             return ERR_PTR(-ENOMEM);
>       edidstr = fwstr;
>  
>       while ((edidname = strsep(&edidstr, ","))) {
> ---
> _______________________________________________
> dri-devel mailing list
> dri-devel@lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/dri-devel

-- 
Jani Nikula, Intel Open Source Graphics Center
_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

Reply via email to