netdev - Re: [PATCH net-next] drivers: net: davinci_mdio: fix potential NULL dereference in davinci_mdio

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Mon, 27 Apr 2020 10:16:47 -0500
From:   David Lechner <david@...hnology.com>
To:     Wei Yongjun <weiyongjun1@...wei.com>,
        Grygorii Strashko <grygorii.strashko@...com>,
        Andrew Lunn <andrew@...n.ch>
Cc:     linux-omap@...r.kernel.org, netdev@...r.kernel.org,
        kernel-janitors@...r.kernel.org
Subject: Re: [PATCH net-next] drivers: net: davinci_mdio: fix potential NULL
 dereference in davinci_mdio_probe()

On 4/27/20 4:40 AM, Wei Yongjun wrote:
> platform_get_resource() may fail and return NULL, so we should
> better check it's return value to avoid a NULL pointer dereference
> a bit later in the code.
> 
> This is detected by Coccinelle semantic patch.
> 
> @@
> expression pdev, res, n, t, e, e1, e2;
> @@
> 
> res = \(platform_get_resource\|platform_get_resource_byname\)(pdev, t, n);
> + if (!res)
> +   return -EINVAL;
> ... when != res == NULL
> e = devm_ioremap(e1, res->start, e2);
> 
> Signed-off-by: Wei Yongjun <weiyongjun1@...wei.com>
> ---
>   drivers/net/ethernet/ti/davinci_mdio.c | 2 ++
>   1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/net/ethernet/ti/davinci_mdio.c b/drivers/net/ethernet/ti/davinci_mdio.c
> index 38b7f6d35759..702fdc393da0 100644
> --- a/drivers/net/ethernet/ti/davinci_mdio.c
> +++ b/drivers/net/ethernet/ti/davinci_mdio.c
> @@ -397,6 +397,8 @@ static int davinci_mdio_probe(struct platform_device *pdev)
>   	data->dev = dev;
>   
>   	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	if (!res)
> +		return -EINVAL;
>   	data->regs = devm_ioremap(dev, res->start, resource_size(res));
>   	if (!data->regs)
>   		return -ENOMEM;
> 

Could we use devm_platform_ioremap_resource() instead?