RE: [PATCH 2/4] misc: xilinx_sdfec: Return -EFAULT if copy_from_user() fails

Dragan Cvetic
2019-08-22T17:47:57Z

Hi Dan,

> -----Original Message-----
> From: Dan Carpenter [mailto:dan.carpenter@oracle.com]
> Sent: Wednesday 21 August 2019 08:07
> To: Derek Kiernan <dkiernan@xilinx.com>; Dragan Cvetic <draganc@xilinx.com>
> Cc: Arnd Bergmann <arnd@arndb.de>; Greg Kroah-Hartman <gregkh@linuxfoundation.org>; Michal Simek <michals@xilinx.com>;
> linux-arm-kernel@lists.infradead.org; linux-kernel@vger.kernel.org; kernel-janitors@vger.kernel.org
> Subject: [PATCH 2/4] misc: xilinx_sdfec: Return -EFAULT if copy_from_user() fails
>
> The copy_from_user() funciton returns the number of bytes remaining to
> be copied but we want to return -EFAULT to the user.
>
> Fixes: 20ec628e8007 ("misc: xilinx_sdfec: Add ability to configure LDPC")
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
> ---
> drivers/misc/xilinx_sdfec.c | 5 +++--
> 1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/misc/xilinx_sdfec.c b/drivers/misc/xilinx_sdfec.c
> index dc1b8b412712..813b82c59360 100644
> --- a/drivers/misc/xilinx_sdfec.c
> +++ b/drivers/misc/xilinx_sdfec.c
> @@ -651,9 +651,10 @@ static int xsdfec_add_ldpc(struct xsdfec_dev *xsdfec, void __user *arg)
> if (!ldpc)
> return -ENOMEM;
>
> - ret = copy_from_user(ldpc, arg, sizeof(*ldpc));
> - if (ret)
> + if (copy_from_user(ldpc, arg, sizeof(*ldpc))) {
> + ret = -EFAULT;
> goto err_out;
> + }
>
> if (xsdfec->config.code == XSDFEC_TURBO_CODE) {
> ret = -EIO;
> --
> 2.20.1

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

Thanks,
Dragan