From: Andy Wingo <wingo@pobox.com>
To: Marius Bakke <marius@gnu.org>
Cc: guile-devel <guile-devel@gnu.org>
Subject: Re: Preventing file descriptor leak to execl'd processes
Date: Fri, 12 Mar 2021 22:22:59 +0100 [thread overview]
Message-ID: <87wnucxe18.fsf@pobox.com> (raw)
In-Reply-To: <87czwc5ijd.fsf@gnu.org> (Marius Bakke's message of "Sat, 06 Mar 2021 17:55:02 +0100")
On Sat 06 Mar 2021 17:55, Marius Bakke <marius@gnu.org> writes:
> $ ls -l /proc/self/fd
> lrwx------ 1 marius marius 64 Mar 6 17:41 0 -> /dev/pts/18
> lrwx------ 1 marius marius 64 Mar 6 17:41 1 -> /dev/pts/18
> lrwx------ 1 marius marius 64 Mar 6 17:41 2 -> /dev/pts/18
> lr-x------ 1 marius marius 64 Mar 6 17:41 3 -> /proc/9940/fd
>
> $ /tmp/test-shell -c 'ls -l /proc/self/fd'
> lrwx------ 1 marius marius 64 Mar 6 17:41 0 -> /dev/pts/18
> lrwx------ 1 marius marius 64 Mar 6 17:41 1 -> /dev/pts/18
> lrwx------ 1 marius marius 64 Mar 6 17:41 2 -> /dev/pts/18
> lr-x------ 1 marius marius 64 Mar 6 17:41 3 -> /proc/9951/fd
> lr-x------ 1 marius marius 64 Mar 6 17:41 7 -> /tmp/test-shell
>
> I've managed to work around it by setting FD_CLOEXEC on it:
>
> (port-for-each (lambda (port)
> (let ((name (port-filename port))
> (self (car (program-arguments))))
> (when (and name (string=? name self))
> (fcntl port F_SETFD (logior FD_CLOEXEC
> (fcntl port F_GETFD)))))))
>
> But it seems heavy-handed. Is there an easier way to access the "script
> port"? Perhaps Guile itself should make it FD_CLOEXEC by default?
I think Guile itself should make the load port FD_CLOEXEC / O_CLOEXEC.
More broadly there are a number of file descriptors in Guile that should
be cloexec but aren't yet. Want to make a patch for the load port ? :)
Andy
prev parent reply other threads:[~2021-03-12 21:22 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-03-06 16:55 Preventing file descriptor leak to execl'd processes Marius Bakke
2021-03-06 18:04 ` Maxime Devos
2021-03-12 21:22 ` Andy Wingo [this message]
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