Date:   Tue, 14 Dec 2021 12:54:13 +0000
From:   Liviu Dudau <liviu.dudau@arm.com>
To:     Jiasheng Jiang <jiasheng@iscas.ac.cn>
Cc:     brian.starkey@arm.com, airlied@linux.ie, daniel@ffwll.ch,
        dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2] drm: mali-dp: potential dereference of null pointer
Message-ID: <YbiT9SZ2sqrl3sJT@e110455-lin.cambridge.arm.com>
References: <20211214125110.46979-1-jiasheng@iscas.ac.cn>
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In-Reply-To: <20211214125110.46979-1-jiasheng@iscas.ac.cn>
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Hi Jiasheng,

On Tue, Dec 14, 2021 at 08:51:10PM +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>
> Reported-by: Brian Starkey <brian.starkey@arm.com>

By R-b Brian meant "Reviewed-by" but I now can see how it can be confused with "Reported-by".

You don't have to send another version of the patch, I will add the correct tag to
your v1 when pushing it into drm-misc-next.

Best regards,
Liviu


> ---
> Changelog:
> 
> v1 -> v2
> 
> *Change 1. Add r-p.
> ---
>  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
> 

-- 
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