Date: Tue, 20 Nov 2012 14:22:26 +0200 From: Jaakko Heinonen <jh@FreeBSD.org> To: Baptiste Daroussin <bapt@FreeBSD.org> Cc: svn-src-head@freebsd.org, svn-src-all@freebsd.org, src-committers@freebsd.org Subject: Re: svn commit: r243328 - head/lib/libutil Message-ID: <20121120122226.GA1828@a91-153-116-96.elisa-laajakaista.fi> In-Reply-To: <201211200722.qAK7M7Im057617@svn.freebsd.org> References: <201211200722.qAK7M7Im057617@svn.freebsd.org>
next in thread | previous in thread | raw e-mail | index | archive | help
Hi!
On 2012-11-20, Baptiste Daroussin wrote:
> change mode the group file to 0644 after a successfull rename(2)
>
> int
> gr_mkdb(void)
> {
> - return (rename(tempname, group_file));
> + int ret;
> +
> + ret = rename(tempname, group_file);
> +
> + if (ret == 0)
> + chmod(group_file, 0644);
> +
> + return (ret);
> }
Rename+chmod is not an atomic operation. There is a window when the file
has wrong permissions. Also, you don't check the return value of
chmod(). Maybe chmod first and then rename?
--
Jaakko
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20121120122226.GA1828>