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Message-ID: <0f017516-58f4-f26e-d598-4be9311e2e27@quicinc.com>
Date:   Thu, 24 Mar 2022 10:56:22 -0700
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Subject: Re: [PATCH] drm/msm/disp: check the return value of kzalloc()
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To:     <xkernel.wang@foxmail.com>, <robdclark@gmail.com>,
        <sean@poorly.run>, <airlied@linux.ie>, <daniel@ffwll.ch>
CC:     <linux-arm-msm@vger.kernel.org>, <freedreno@lists.freedesktop.org>,
        <linux-kernel@vger.kernel.org>, <dri-devel@lists.freedesktop.org>
References: <tencent_B3E19486FF39415098B572B7397C2936C309@qq.com>
From:   Abhinav Kumar <quic_abhinavk@quicinc.com>
In-Reply-To: <tencent_B3E19486FF39415098B572B7397C2936C309@qq.com>
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On 3/24/2022 2:15 AM, xkernel.wang@foxmail.com wrote:
> From: Xiaoke Wang <xkernel.wang@foxmail.com>
> 
> kzalloc() is a memory allocation function which can return NULL when
> some internal memory errors happen. So it is better to check it to
> prevent potential wrong memory access.
> 
> Signed-off-by: Xiaoke Wang <xkernel.wang@foxmail.com>
Reviewed-by: Abhinav Kumar <quic_abhinavk@quicinc.com>
> ---
>   drivers/gpu/drm/msm/disp/msm_disp_snapshot_util.c | 2 ++
>   1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/gpu/drm/msm/disp/msm_disp_snapshot_util.c b/drivers/gpu/drm/msm/disp/msm_disp_snapshot_util.c
> index cabe151..369e57f 100644
> --- a/drivers/gpu/drm/msm/disp/msm_disp_snapshot_util.c
> +++ b/drivers/gpu/drm/msm/disp/msm_disp_snapshot_util.c
> @@ -169,6 +169,8 @@ void msm_disp_snapshot_add_block(struct msm_disp_state *disp_state, u32 len,
>   	va_list va;
>   
>   	new_blk = kzalloc(sizeof(struct msm_disp_state_block), GFP_KERNEL);
> +	if (!new_blk)
> +		return;
>   
>   	va_start(va, fmt);
>