From mboxrd@z Thu Jan  1 00:00:00 1970
From: Or Gerlitz <ogerlitz@mellanox.com>
Subject: Re: [patch -next] mlx5_core: return -EFAULT if copy_to_user() fails
Date: Wed, 10 Jul 2013 14:37:03 +0300
Message-ID: <51DD475F.4060402@mellanox.com>
References: <20130710105714.GC31232@longonot.mountain>
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In-Reply-To: <20130710105714.GC31232@longonot.mountain>
Sender: kernel-janitors-owner@vger.kernel.org
To: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Eli Cohen <eli@mellanox.com>, linux-rdma@vger.kernel.org, kernel-janitors@vger.kernel.org, Jack Morgenstein <jackm@dev.mellanox.co.il>, Moshe Lazer <moshel@mellanox.com>
List-Id: linux-rdma@vger.kernel.org

On 10/07/2013 13:57, Dan Carpenter wrote:
> This should return an error code instead of the number of bytes
> remaining to be copied.
>
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
>
> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/debugfs.c b/drivers/net/ethernet/mellanox/mlx5/core/debugfs.c
> index a550a8e..4273c06 100644
> --- a/drivers/net/ethernet/mellanox/mlx5/core/debugfs.c
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/debugfs.c
> @@ -148,7 +148,6 @@ static ssize_t average_read(struct file *filp, char __user *buf, size_t count,
>   	struct mlx5_cmd_stats *stats;
>   	u64 field = 0;
>   	int ret;
> -	int err;
>   	char tbuf[22];
>   
>   	if (*pos)
> @@ -161,9 +160,8 @@ static ssize_t average_read(struct file *filp, char __user *buf, size_t count,
>   	spin_unlock(&stats->lock);
>   	ret = snprintf(tbuf, sizeof(tbuf), "%llu\n", field);
>   	if (ret > 0) {
> -		err = copy_to_user(buf, tbuf, ret);
> -		if (err)
> -			return err;
> +		if (copy_to_user(buf, tbuf, ret))
> +			return -EFAULT;
>   	}
>   
>   	*pos += ret;
> @@ -418,7 +416,6 @@ static ssize_t dbg_read(struct file *filp, char __user *buf, size_t count,
>   	char tbuf[18];
>   	u64 field;
>   	int ret;
> -	int err;
>   
>   	if (*pos)
>   		return 0;
> @@ -445,9 +442,8 @@ static ssize_t dbg_read(struct file *filp, char __user *buf, size_t count,
>   
>   	ret = snprintf(tbuf, sizeof(tbuf), "0x%llx\n", field);
>   	if (ret > 0) {
> -		err = copy_to_user(buf, tbuf, ret);
> -		if (err)
> -			return err;
> +		if (copy_to_user(buf, tbuf, ret))
> +			return -EFAULT;
>   	}
>   
>   	*pos += ret;
>

ditto here

Acked-by: Or Gerlitz <ogerlitz@mellanox.com>