Re: [PATCH net-next v6 01/18] net: Declare MSG_SPLICE_PAGES internal sendmsg() flag

[Al Viro <viro@xxxxxxxxxxxxxxxxxx>]

On Tue, Apr 11, 2023 at 05:08:45PM +0100, David Howells wrote:

> @@ -2483,6 +2484,7 @@ static int ____sys_sendmsg(struct socket *sock, struct msghdr *msg_sys,
>  	}
>  	msg_sys->msg_flags = flags;
>  
> +	flags &= ~MSG_INTERNAL_SENDMSG_FLAGS;
>  	if (sock->file->f_flags & O_NONBLOCK)
>  		msg_sys->msg_flags |= MSG_DONTWAIT;

A bit too late, innit?  There's no users of 'flags' downstream of that
assignment to ->msg_flags, so your &= is a no-op; it should be done
*before* that assignment...