Re: [RFC] situation with csum_and_copy_... API

On Fri, 2014-11-21 at 08:49 +0000, Al Viro wrote:

Another thing is tcp_sendmsg_fastopen() and tcp_send_rcvq().  The latter
should just use copy_from_iter() instead of memcpy_from_iovec(), the former
is dealt with by making tcp_send_syn_data() use the same copy_from_iter()
instead of memcpy_from_iovecend().

Well, another problem I already mentioned is that tcp_send_rcvq() does a
single alloc_skb() with @size directly coming from user space. This
certainly can try allocation of dozen of Megabytes.

Not good.