From: Solar Designer <solar@openwall.com>
To: kernel-hardening@lists.openwall.com
Subject: Re: [kernel-hardening] procfs: infoleaks and DAC permissions
Date: Sat, 11 Feb 2012 17:31:46 +0400 [thread overview]
Message-ID: <20120211133146.GA19489@openwall.com> (raw)
In-Reply-To: <20120211102105.GA18464@albatros>
On Sat, Feb 11, 2012 at 02:21:06PM +0400, Vasiliy Kulikov wrote:
> On Sat, Feb 11, 2012 at 13:20 +0400, Solar Designer wrote:
> > I did not look into this closely, but my current understanding is that
> > apparently glibc reads the process' own proc files only, and restricting
> > their perms to 0400 breaks this if the process changes euid/fsuid during
> > its runtime. Right?
>
> Yes, AFAICS, it looks whether a specific memory area is RW. But looking
> at "grep -r /proc/self/ glibc-sources/" output I can say /proc/self/maps
> is not the only file usage which might be broken by open() restricting.
Yes, and not all pathnames are constant - there's also
"/proc/self/task/%u/comm".
Alexander
next prev parent reply other threads:[~2012-02-11 13:31 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-02-10 2:06 [kernel-hardening] procfs: infoleaks and DAC permissions Djalal Harouni
2012-02-10 14:36 ` Vasiliy Kulikov
2012-02-11 9:20 ` Solar Designer
2012-02-11 10:21 ` Vasiliy Kulikov
2012-02-11 13:31 ` Solar Designer [this message]
2012-02-12 0:19 ` Djalal Harouni
2012-02-21 14:56 ` Solar Designer
2012-02-21 16:25 ` Djalal Harouni
2012-02-21 17:42 ` Solar Designer
2012-02-24 0:56 ` Solar Designer
2012-02-25 3:56 ` Solar Designer
2012-03-03 0:35 ` Djalal Harouni
2012-02-21 16:34 ` Djalal Harouni
2012-02-11 10:07 ` Solar Designer
2012-02-12 15:36 ` Djalal Harouni
2012-02-13 15:50 ` Djalal Harouni
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