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Message-ID: <354d17d2e1e55b12428fcb50f7cfce9bea81ea29.camel@pengutronix.de>
Subject: Re: [PATCH] media: coda: Add check for dcoda_iram_alloc
From:   Philipp Zabel <p.zabel@pengutronix.de>
To:     Jiasheng Jiang <jiasheng@iscas.ac.cn>, mchehab@kernel.org
Cc:     linux-media@vger.kernel.org, linux-kernel@vger.kernel.org
Date:   Fri, 16 Dec 2022 18:32:09 +0100
In-Reply-To: <20221117065652.44426-1-jiasheng@iscas.ac.cn>
References: <20221117065652.44426-1-jiasheng@iscas.ac.cn>
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On Do, 2022-11-17 at 14:56 +0800, Jiasheng Jiang wrote:
> As the coda_iram_alloc may return NULL pointer,

coda_iram_alloc() may return (phys_addr_t)0, not a NULL pointer.

> it should be better to check the return value
> in order to avoid NULL poineter dereference,
> same as the others.
> 
> Fixes: b313bcc9a467 ("[media] coda: simplify IRAM setup")
> Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn>
> ---
>  drivers/media/platform/chips-media/coda-bit.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/media/platform/chips-media/coda-bit.c b/drivers/media/platform/chips-media/coda-bit.c
> index 2736a902e3df..6d816fd69a17 100644
> --- a/drivers/media/platform/chips-media/coda-bit.c
> +++ b/drivers/media/platform/chips-media/coda-bit.c
> @@ -854,7 +854,7 @@ static void coda_setup_iram(struct coda_ctx *ctx)
>  		/* Only H.264BP and H.263P3 are considered */
>  		iram_info->buf_dbk_y_use = coda_iram_alloc(iram_info, w64);

While this can return 0, if this allocation fails, ...

>  		iram_info->buf_dbk_c_use = coda_iram_alloc(iram_info, w64);

... this one must fail as well.

> -		if (!iram_info->buf_dbk_c_use)

So the buf_dbk_c_use check is enough.

regards
Philipp