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Date: Fri, 9 Jan 2015 20:56:26 +0000
From: Al Viro <viro@ZenIV.linux.org.uk>
To: Rich Felker <dalias@aerifal.cx>
Cc: David Drysdale <drysdale@google.com>,
        "Michael Kerrisk (man-pages)" <mtk.manpages@gmail.com>,
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Subject: Re: [PATCHv10 man-pages 5/5] execveat.2: initial man page for
 execveat(2)
Message-ID: <20150109205626.GK22149@ZenIV.linux.org.uk>
References: <1416830039-21952-1-git-send-email-drysdale@google.com>
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 <20150109161302.GQ4574@brightrain.aerifal.cx>
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On Fri, Jan 09, 2015 at 03:48:15PM -0500, Rich Felker wrote:
> I think this is a case that needs to be fixed, though it's hard. The
> normal correct usage for fexecve is to always pass an O_CLOEXEC file
> descriptor, and the caller can't really be expected to know whether
> the file is a script or not. We discussed workarounds before and one
> idea I proposed was having fexecve provide a "one open only" magic
> symlink in /proc/self/ to pass to the interpreter. It would behave
> like an O_PATH file descriptor magic symlink in /proc/self/fd, but
> would automatically cease to exist on the first open (at which point
> the interpreter would have a real O_RDONLY file descriptor for the
> underlying file).

For fsck sake, folks, if you have bloody /proc, you don't need that shite
at all!  Just do execve on /proc/self/fd/n, and be done with that.

The sole excuse for merging that thing in the first place had been
"would anybody think of children^Wsclerotic^Whardened environments
where they have no /proc at all".

Sheesh...