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Message-ID: <517f3f820811140724l49dd0f31xffda837afd1986a8@mail.gmail.com>
Date: Fri, 14 Nov 2008 10:24:22 -0500
From: "Michael Kerrisk" <mtk.manpages@gmail.com>
To: "Andrew Morton" <akpm@linux-foundation.org>
Subject: Re: [PATCH] reintroduce accept4
Cc: "Paul Mackerras" <paulus@samba.org>, subrata@linux.vnet.ibm.com,
       linux-arch@vger.kernel.org, drepper@redhat.com,
       linux-kernel@vger.kernel.org, torvalds@linux-foundation.org,
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       oleg@tv-sign.ru, hch@lst.de, davem@davemloft.net, alan@redhat.com,
       jakub@redhat.com
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Andrew,

> From: Ulrich Drepper <drepper@redhat.com>
>
> Introduce a new accept4() system call.  The addition of this system call
> matches analogous changes in 2.6.27 (dup3(), evenfd2(), signalfd4(),
> inotify_init1(), epoll_create1(), pipe2()) which added new system calls
> that differed from analogous traditional system calls in adding a flags
> argument that can be used to access additional functionality.
>
> The accept4() system call is exactly the same as accept(), except that it
> adds a flags bit-mask argument.  Two flags are initially implemented.
> (Most of the new system calls in 2.6.27 also had both of these flags.)

Add a para break here.

> SOCK_CLOEXEC causes the close-on-exec (FD_CLOEXEC) flag to be enabled for
> the new file descriptor returned by accept4().  This is a useful security
> feature to avoid leaking information in a multithreaded program where one
> thread is doing an accept() at the same time as another thread is doing a
> fork() plus exec().
>

This para break is in the wrong place.

> More details here: http://udrepper.livejournal.com/20407.html "Secure File
> Descriptor Handling", Ulrich Drepper) The other flag is SOCK_NONBLOCK,

The para break should actually be at the sentence break in the previous line.

Cheers,

Michael
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