supervision - discussion about system services, daemon supervision, init, runlevel management, and tools such as s6 and runit
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From: eam@frap.net
To: supervision@list.skarnet.org
Subject: Re: Default permissions on supervise/ok
Date: Tue, 21 May 2013 08:29:50 -0700	[thread overview]
Message-ID: <20130521152950.GA10740@frap.net> (raw)
In-Reply-To: <20130521095814.GA2290@skarnet.org>

On Tue, May 21, 2013 at 11:58:14AM +0200, Laurent Bercot wrote:
> > My understanding is that runsv will never read from the fifo, and will
> > only use opening it as a test to verify the process exists the other end.
> > This doesn't seem exploitable as it's a read-only channel. At least, as
> > far as I can tell.
> 
>  Here's an exploit:
> 
>  If runsv is down, "sv status" will normally return a "runsv not running"
> message. But if some user has supervise/ok open for reading, "sv status"
> will mistakenly think runsv is running, because it assumes runsv is the
> only process able to keep supervise/ok open for reading. So, a user can
> deny a service recovery routine from running.

Hm, interesting. Though 622 permissions would correct this, right?
Writable, but not readable?

Any concerns about making the directory readable and executable?


  reply	other threads:[~2013-05-21 15:29 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-05-20 23:52 eam
2013-05-21  0:47 ` Charlie Brady
2013-05-21  4:43   ` eam
2013-05-21  9:58     ` Laurent Bercot
2013-05-21 15:29       ` eam [this message]
2013-05-21 15:10         ` Laurent Bercot

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