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Date:   Tue, 14 Dec 2021 11:02:02 +0000
From:   Brian Starkey <brian.starkey@arm.com>
To:     Jiasheng Jiang <jiasheng@iscas.ac.cn>
Cc:     liviu.dudau@arm.com, airlied@linux.ie, daniel@ffwll.ch,
        dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org,
        nd@arm.com
Subject: Re: [PATCH] drm: mali-dp: potential dereference of null pointer
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Hi,

On Tue, Dec 14, 2021 at 06:08:37PM +0800, Jiasheng Jiang wrote:
> The return value of kzalloc() needs to be checked.
> To avoid use of null pointer '&state->base' in case of the
> failure of alloc.
> 
> Fixes: 99665d072183 ("drm: mali-dp: add malidp_crtc_state struct")
> Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn>
> ---

You can add my r-b to this one too. Thanks!

>  drivers/gpu/drm/arm/malidp_crtc.c | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/arm/malidp_crtc.c b/drivers/gpu/drm/arm/malidp_crtc.c
> index 494075ddbef6..b5928b52e279 100644
> --- a/drivers/gpu/drm/arm/malidp_crtc.c
> +++ b/drivers/gpu/drm/arm/malidp_crtc.c
> @@ -487,7 +487,10 @@ static void malidp_crtc_reset(struct drm_crtc *crtc)
>  	if (crtc->state)
>  		malidp_crtc_destroy_state(crtc, crtc->state);
>  
> -	__drm_atomic_helper_crtc_reset(crtc, &state->base);
> +	if (state)
> +		__drm_atomic_helper_crtc_reset(crtc, &state->base);
> +	else
> +		__drm_atomic_helper_crtc_reset(crtc, NULL);
>  }
>  
>  static int malidp_crtc_enable_vblank(struct drm_crtc *crtc)
> -- 
> 2.25.1
>