Re: [PATCH mptcp-next v3 1/7] mptcp: drop unused @max arg of __mptcp_setsockopt_set_val

On Mon, 2026-07-27 at 10:28 +0800, Gang Yan wrote:
> From: Gang Yan <[email protected]>
> 
> The @max argument is never read in the function body. Remove it and
> the
> MAX_TCP_KEEP* values passed by the TCP_KEEPIDLE/INTVL/KEEPCNT
> callers.

No, we shouldn't drop this "max" argument. Instead, we need to add some
code to check the "val" argument against the "max" argument in
__mptcp_setsockopt_set_val(), something like:

        if (val < 1 || val > max) 
                return -EINVAL;

> 
> Signed-off-by: Gang Yan <[email protected]>
> ---
>  net/mptcp/sockopt.c | 11 ++++-------
>  1 file changed, 4 insertions(+), 7 deletions(-)
> 
> diff --git a/net/mptcp/sockopt.c b/net/mptcp/sockopt.c
> index fcf6feb2a9eb..9c4faa0d82ef 100644
> --- a/net/mptcp/sockopt.c
> +++ b/net/mptcp/sockopt.c
> @@ -632,7 +632,7 @@ static int
> mptcp_setsockopt_sol_tcp_congestion(struct mptcp_sock *msk, sockptr_t
>  	return ret;
>  }
>  
> -static int __mptcp_setsockopt_set_val(struct mptcp_sock *msk, int
> max,
> +static int __mptcp_setsockopt_set_val(struct mptcp_sock *msk,
>  				      int (*set_val)(struct sock *,
> int),
>  				      int *msk_val, int val)
>  {
> @@ -876,18 +876,15 @@ static int mptcp_setsockopt_sol_tcp(struct
> mptcp_sock *msk, int optname,
>  		ret = __mptcp_setsockopt_sol_tcp_nodelay(msk, val);
>  		break;
>  	case TCP_KEEPIDLE:
> -		ret = __mptcp_setsockopt_set_val(msk,
> MAX_TCP_KEEPIDLE,
> -						
> &tcp_sock_set_keepidle_locked,
> +		ret = __mptcp_setsockopt_set_val(msk,
> &tcp_sock_set_keepidle_locked,
>  						 &msk-
> >keepalive_idle, val);
>  		break;
>  	case TCP_KEEPINTVL:
> -		ret = __mptcp_setsockopt_set_val(msk,
> MAX_TCP_KEEPINTVL,
> -						
> &tcp_sock_set_keepintvl,
> +		ret = __mptcp_setsockopt_set_val(msk,
> &tcp_sock_set_keepintvl,
>  						 &msk-
> >keepalive_intvl, val);
>  		break;
>  	case TCP_KEEPCNT:
> -		ret = __mptcp_setsockopt_set_val(msk,
> MAX_TCP_KEEPCNT,
> -						
> &tcp_sock_set_keepcnt,
> +		ret = __mptcp_setsockopt_set_val(msk,
> &tcp_sock_set_keepcnt,
>  						 &msk-
> >keepalive_cnt,
>  						 val);
>  		break;