Date: Mon, 5 Dec 2016 23:52:00 +0300
From: Dan Carpenter <dan.carpenter@oracle.com>
To: Quentin Lambert <lambert.quentin@gmail.com>
Cc: Oleg Drokin <oleg.drokin@intel.com>,
        Andreas Dilger <andreas.dilger@intel.com>,
        James Simmons <jsimmons@infradead.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        lustre-devel@lists.lustre.org, devel@driverdev.osuosl.org,
        linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org
Subject: Re: [PATCH] staging: lustre: Fix a spatch warning due to an
 assignment from kernel to user space
Message-ID: <20161205205200.GB31243@mwanda>
References: <20161202173332.5100-1-lambert.quentin@gmail.com>
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On Fri, Dec 02, 2016 at 06:33:32PM +0100, Quentin Lambert wrote:
> lnet_ipif_enumerate was assigning a pointer from kernel space to user
> space. This patch uses copy_to_user to properly do that assignment.

Put the exact warning message here.

> 
> Signed-off-by: Quentin Lambert <lambert.quentin@gmail.com>
> ---
>  shouldn't we be using ifc_req instead of ifc_buf?
> 
>  drivers/staging/lustre/lnet/lnet/lib-socket.c |    8 +++++++-
>  1 file changed, 7 insertions(+), 1 deletion(-)
> 
> --- a/drivers/staging/lustre/lnet/lnet/lib-socket.c
> +++ b/drivers/staging/lustre/lnet/lnet/lib-socket.c
> @@ -181,7 +181,13 @@ lnet_ipif_enumerate(char ***namesp)
>  			goto out0;
>  		}
>  
> -		ifc.ifc_buf = (char *)ifr;
> +		rc = copy_to_user(ifc.ifc_buf, (char *)ifr,
> +				  nalloc * sizeof(*ifr));
> +		if (rc) {
> +			rc = -ENOMEM;
> +			goto out1;
> +		}


No idea what's going on here.  The original code is correct.

regards,
dan carpenter