Re: [PATCH mptcp-next v2 3/5] mptcp: add MPTCP_TCPINFO getsockopt support

[Mat Martineau <mathew.j.martineau@linux.intel.com>]

On Mon, 16 Aug 2021, Florian Westphal wrote:

> diff --git a/net/mptcp/sockopt.c b/net/mptcp/sockopt.c
> index f7683c22911f..77838933760c 100644
> --- a/net/mptcp/sockopt.c
> +++ b/net/mptcp/sockopt.c

...

> @@ -727,6 +729,117 @@ static int mptcp_getsockopt_info(struct mptcp_sock *msk, char __user *optval, in
> 	return 0;
> }
>
> +static int mptcp_put_subflow_data(struct mptcp_subflow_data *sfd,
> +				  char __user *optval,
> +				  u32 copied,
> +				  int __user *optlen)
> +{
> +	u32 copylen = min_t(u32, sfd->size_subflow_data, sizeof(*sfd));
> +
> +	if (copied)
> +		copied += sfd->size_subflow_data;
> +	else
> +		copied = copylen;
> +
> +	if (put_user(copied, optlen))
> +		return -EFAULT;
> +
> +	if (copy_to_user(optval, sfd, copylen))
> +		return -EFAULT;
> +
> +	return 0;
> +}
> +
> +static int mptcp_get_subflow_data(struct mptcp_subflow_data *sfd,
> +				  char __user *optval, int __user *optlen)
> +{
> +	int len, copylen;
> +
> +	if (get_user(len, optlen))
> +		return -EFAULT;
> +
> +	/* if mptcp_subflow_data size is changed, need to adjust
> +	 * this function to deal with programs using old version.
> +	 */
> +	BUILD_BUG_ON(MIN_INFO_OPTLEN_SIZE != sizeof(*sfd));

checkpatch complains that the constant should be on the right.


--
Mat Martineau
Intel