[PATCH -next] misc: xilinx_sdfec: Use memdup_user() as a cleanup

[PATCH -next] misc: xilinx_sdfec: Use memdup_user() as a cleanup

[Zou Wei]

Fix coccicheck warning which recommends to use memdup_user().

This patch fixes the following coccicheck warnings:

drivers/misc/xilinx_sdfec.c:652:8-15: WARNING opportunity for memdup_user

Fixes: 20ec628e8007 ("misc: xilinx_sdfec: Add ability to configure LDPC")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Zou Wei <zou_wei@huawei.com>
---
 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 71bbaa5..7a75894 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;
-- 
2.6.2

RE: [PATCH -next] misc: xilinx_sdfec: Use memdup_user() as a cleanup

[Dragan Cvetic]

Hi Zou,

Thanks for fixing the warning.

> -----Original Message-----
> From: Zou Wei <zou_wei@huawei.com>
> Sent: Wednesday 22 April 2020 03:59
> To: Derek Kiernan <dkiernan@xilinx.com>; Dragan Cvetic <draganc@xilinx.com>; arnd@arndb.de; gregkh@linuxfoundation.org;
> Michal Simek <michals@xilinx.com>
> Cc: linux-arm-kernel@lists.infradead.org; linux-kernel@vger.kernel.org; Zou Wei <zou_wei@huawei.com>
> Subject: [PATCH -next] misc: xilinx_sdfec: Use memdup_user() as a cleanup
> 
> Fix coccicheck warning which recommends to use memdup_user().
> 
> This patch fixes the following coccicheck warnings:
> 
> drivers/misc/xilinx_sdfec.c:652:8-15: WARNING opportunity for memdup_user
> 
> Fixes: 20ec628e8007 ("misc: xilinx_sdfec: Add ability to configure LDPC")
> Reported-by: Hulk Robot <hulkci@huawei.com>
> Signed-off-by: Zou Wei <zou_wei@huawei.com>
> ---
>  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 71bbaa5..7a75894 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;
> --
> 2.6.2

Acked-by: Dragan Cvetic <dragan.cvetic@xilinx.com>


Regards
Dragan