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] [thread-next>] [day] [month] [year] [list]
Message-ID: <4702465C.7030207@rtr.ca>
Date:	Tue, 02 Oct 2007 09:23:40 -0400
From:	Mark Lord <lkml@....ca>
To:	gogi-k@...i.tv
Cc:	linux-kernel@...r.kernel.org
Subject: Re: One process with multiple user ids.

Giuliano Gagliardi wrote:
> On Tuesday 02 October 2007, Jan Engelhardt wrote:
>> On Oct 2 2007 12:56, Giuliano Gagliardi wrote:
>>> I have a server that has to switch to different user ids, but because it
>>> does other complex things, I would rather not have it run as root. I only
>>> need the server to be able to switch to certain pre-defined user ids.
>> All you need is CAP_SETUID. Also see man setresuid,
>> where you could, I think, use saved_uid=0 if you do not
>> like to use real_uid=0 effective_uid=non-0.
> 
> But CAP_SETUID would let me change to any uid, would it not? I would like my 
> process to have no possibility to change to any uid, except some predefined 
> set, so that in case of a security hole only those uids could be compromised.

It really sounds like the app should be restructured.
If security is that important to it, then it shouldn't
be changing uids back and forth on the fly (too risky).

There's probably a nice redesign possible where it just
forks off 3 sub-processes, one for each UID,
and then farms out the work to each as required.

Cheers
-
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/

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ