linux-kernel - Re: [RFC] fs, proc: Introduce the /proc/<pid>/map

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <4E6F66C8.5020406@parallels.com>
Date:	Tue, 13 Sep 2011 18:20:56 +0400
From:	Pavel Emelyanov <xemul@...allels.com>
To:	Pavel Machek <pavel@....cz>
CC:	Cyrill Gorcunov <gorcunov@...il.com>, Nathan Lynch <ntl@...ox.com>,
	Oren Laadan <orenl@...columbia.edu>,
	Daniel Lezcano <dlezcano@...ibm.com>,
	Tejun Heo <tj@...nel.org>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Glauber Costa <glommer@...allels.com>,
	"containers@...ts.osdl.org" <containers@...ts.osdl.org>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	Serge Hallyn <serge.hallyn@...onical.com>,
	LINUXFS-ML <linux-fsdevel@...r.kernel.org>,
	James Bottomley <jbottomley@...allels.com>
Subject: Re: [RFC] fs, proc: Introduce the /proc/<pid>/map_files/ directory
 v2

On 09/13/2011 06:14 PM, Pavel Machek wrote:
> Hi!
> 
>> This one behaves similarly to the /proc/<pid>/fd/ one - it contains symlinks
>> one for each mapping with file, the name of a symlink is vma->vm_start, the
>> target is the file. Opening a symlink results in a file that point exactly
>> to the same inode as them vma's one.
> 
> Is it good idea security-wise? It looks like symlink but does not
> behave like one. (And yes, I know we already have similar problems in
> /proc..)

What exactly doesn't behave like symlink, can you elaborate, please?

> ptrace-may-trace is not good enough protection; I can do  this on my
> own thread to get around read-only protection on fd. (File can be
> protected from me by directory permissions.)

I think this issue worth separate discussion and if it turns out there is
a problem with that we can fix it together with /proc/pid/fd and other stuff.

Thanks,
Pavel
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/