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Date:   Mon, 14 Nov 2022 09:04:08 +0100
From:   Miquel Raynal <miquel.raynal@bootlin.com>
To:     Hui Tang <tanghui20@huawei.com>
Cc:     <richard@nod.at>, <vigneshr@ti.com>,
        <u.kleine-koenig@pengutronix.de>, <linux-mtd@lists.infradead.org>,
        <linux-kernel@vger.kernel.org>, <weiyongjun1@huawei.com>,
        <yusongping@huawei.com>
Subject: Re: [PATCH] mtd: lpddr2_nvm: i2c: mux: reg: Fix possible
 null-ptr-deref
Message-ID: <20221114090408.7ed0e7c1@xps-13>
In-Reply-To: <20221114020141.28138-1-tanghui20@huawei.com>
References: <20221114020141.28138-1-tanghui20@huawei.com>
Organization: Bootlin
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Hi Hui,

tanghui20@huawei.com wrote on Mon, 14 Nov 2022 10:01:41 +0800:

> It will cause null-ptr-deref when resource_size(add_range) invoked,
> if platform_get_resource() returns NULL.
>=20
> Fixes: 96ba9dd65788 ("mtd: lpddr: add driver for LPDDR2-NVM PCM memories")
> Signed-off-by: Hui Tang <tanghui20@huawei.com>
> ---
>  drivers/mtd/lpddr/lpddr2_nvm.c | 2 ++
>  1 file changed, 2 insertions(+)
>=20
> diff --git a/drivers/mtd/lpddr/lpddr2_nvm.c b/drivers/mtd/lpddr/lpddr2_nv=
m.c
> index 367e2d906de0..cf8e86eb4b2c 100644
> --- a/drivers/mtd/lpddr/lpddr2_nvm.c
> +++ b/drivers/mtd/lpddr/lpddr2_nvm.c
> @@ -433,6 +433,8 @@ static int lpddr2_nvm_probe(struct platform_device *p=
dev)
> =20
>  	/* lpddr2_nvm address range */
>  	add_range =3D platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	if (IS_ERR(add_range))

platform_get_resource() just returns NULL upon error.

> +		return -ENODEV;
> =20
>  	/* Populate map_info data structure */
>  	*map =3D (struct map_info) {


Thanks,
Miqu=C3=A8l