Date: Sun, 8 Jul 2007 21:17:27 +0400
From: Andrey Chernov <ache@nagual.pp.ru>
To: "Sean C. Farley" <scf@FreeBSD.org>, Robert Watson <rwatson@FreeBSD.org>, freebsd-current <freebsd-current@FreeBSD.org>, Michal Mertl <mime@traveller.cz>
Subject: Re: Environment handling broken in /bin/sh with changes to {get,set,put}env()
Message-ID: <20070708171727.GA90490@nagual.pp.ru>
In-Reply-To: <20070708020940.GA80166@nagual.pp.ru>
References: <20070704235630.GA42227@nagual.pp.ru> <20070704215154.O77978@thor.farley.org> <20070705115816.GA50506@nagual.pp.ru> <20070705105922.F98700@thor.farley.org> <20070707130859.GA96605@nagual.pp.ru> <20070707131359.GB96605@nagual.pp.ru> <20070707133102.C14065@thor.farley.org> <20070707191835.GA4368@nagual.pp.ru> <20070707205410.B14065@thor.farley.org> <20070708020940.GA80166@nagual.pp.ru>
next in thread | previous in thread | raw e-mail | index | archive | help
On Sun, Jul 08, 2007 at 06:09:40AM +0400, Andrey Chernov wrote:
> On Sat, Jul 07, 2007 at 09:03:59PM -0500, Sean C. Farley wrote:
> >
> > Surprisingly, keeping the pointers saved time even if calling setenv().
>
> Ok. It feels like time to commit comes :)
Hmm. I just think a bit more and feel worry about that place in the merge
code:
*equals = '\0';
if (setenv(*env, equals + 1, 1) == -1)
return (-1);
*equals = '=';
because it modifies memory which may be treated like const one.
Consider following scenario: getenv() is not thread-safe, but may be
called by thread-safe app if it is sure no other *env() calls in progress.
In the same time another thread of this app use environ directly say for
exec(), assuming it is const. In the middle of that getenv() modifies
environ by *equals = '\0';
Could you please make setenv() wrapper like that to avoid modifying merged
environ in the middle?
__lsetenv(str, str_len, value)
--
http://ache.pp.ru/
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20070708171727.GA90490>