From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH] LSM: Add post recvmsg() hook.
Date: Fri, 23 Jul 2010 00:29:13 -0700 (PDT)
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From: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Date: Fri, 23 Jul 2010 16:21:38 +0900

> Users calling recvmsg() after select() said "read operation will return with
> available data without blocking as long as you pass correct parameters" will
> get error code even if they passed correct parameters.

This is nonsense, because not all "parameters" are not visible to poll().

These "parameters" I speak of are virtual, they are my way of saying
that the errors returned by the existing LSM hooks are more like -EFAULT
or -EACCESS than -EINTR/-EAGAIN or blocking, the latter of which are
what are illegal for blocking socket invoking recvmsg() after poll
indicates there is data to read.