From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: Add a SOCK_DESTROY operation to close sockets from userspace
Date: Thu, 19 Nov 2015 00:53:18 -0500 (EST)
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From: Lorenzo Colitti <lorenzo@google.com>
Date: Thu, 19 Nov 2015 14:13:48 +0900

> On Thu, Nov 19, 2015 at 12:49 PM, David Miller <davem@davemloft.net> wrote:
>> The more I think about it more the more I agree with him and dislike
>> having user space make sure "it's ok", that isn't where TCP protocol
>> semantic rules are implemented.  It belongs in the kernel.
> 
> Today any app can always, on one of its sockets, set SO_LINGER with a
> timeout of 0 and call tcp_close. That results in immediately sending a
> RST and forgetting about local state. (Those semantics are the ones of
> RFC 793 ABORT.) If SOCK_DESTROY did that instead of just calling
> tcp_done, would that be acceptable?

What I object to is userspace making reachability decisions, not
whether SOCK_DESTROY closes the socket in one way or the other.