RE: [PATCH 1/2] misc: xilinx_sdfec: Use memdup_user() rather than duplicating its implementation

[Dragan Cvetic]

HI Markus,

Thanks for the nice solution,
we are going to test this change and let you know about the result.

Regards
Dragan


> -----Original Message-----
> From: Markus Elfring [mailto:Markus.Elfring@xxxxxx]
> Sent: Tuesday 5 November 2019 18:55
> To: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; Arnd Bergmann <arnd@xxxxxxxx>; Derek Kiernan <dkiernan@xxxxxxxxxx>; Dragan Cvetic
> <draganc@xxxxxxxxxx>; Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>; Michal Simek <michals@xxxxxxxxxx>
> Cc: LKML <linux-kernel@xxxxxxxxxxxxxxx>; kernel-janitors@xxxxxxxxxxxxxxx
> Subject: [PATCH 1/2] misc: xilinx_sdfec: Use memdup_user() rather than duplicating its implementation
> 
> From: Markus Elfring <elfring@xxxxxxxxxxxxxxxxxxxxx>
> Date: Tue, 5 Nov 2019 19:09:15 +0100
> 
> Reuse existing functionality from memdup_user() instead of keeping
> duplicate source code.
> 
> Generated by: scripts/coccinelle/api/memdup_user.cocci
> 
> Fixes: 20ec628e8007ec75c2f884e00004f39eab6289b5 ("misc: xilinx_sdfec: Add ability to configure LDPC")
> Signed-off-by: Markus Elfring <elfring@xxxxxxxxxxxxxxxxxxxxx>
> ---
>  drivers/misc/xilinx_sdfec.c | 11 +++--------
>  1 file changed, 3 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/misc/xilinx_sdfec.c b/drivers/misc/xilinx_sdfec.c
> index 11835969e982..a622fcf4954a 100644
> --- a/drivers/misc/xilinx_sdfec.c
> +++ b/drivers/misc/xilinx_sdfec.c
> @@ -649,14 +649,9 @@ static int xsdfec_add_ldpc(struct xsdfec_dev *xsdfec, void __user *arg)
>  	struct xsdfec_ldpc_params *ldpc;
>  	int ret, n;
> 
> -	ldpc = kzalloc(sizeof(*ldpc), GFP_KERNEL);
> -	if (!ldpc)
> -		return -ENOMEM;
> -
> -	if (copy_from_user(ldpc, arg, sizeof(*ldpc))) {
> -		ret = -EFAULT;
> -		goto err_out;
> -	}
> +	ldpc = memdup_user(arg, sizeof(*ldpc));
> +	if (IS_ERR(ldpc))
> +		return PTR_ERR(ldpc);
> 
>  	if (xsdfec->config.code == XSDFEC_TURBO_CODE) {
>  		ret = -EIO;
> --
> 2.24.0