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From: Alasdair G Kergon <agk@redhat.com>
To: LVM general discussion and development <linux-lvm@redhat.com>
Subject: Re: [linux-lvm] lvcreate from a setuid-root binary
Date: Mon, 19 Nov 2018 13:01:50 +0000	[thread overview]
Message-ID: <20181119130150.GA487@agk-dp.fab.redhat.com> (raw)
In-Reply-To: <25b87d17a683075e57f45422ee3ef7f6@cs.uni-dortmund.de>

On Mon, Nov 19, 2018 at 09:55:07AM +0100, Christoph Pleger wrote:
> My program calls getpwuid() with the real user id of the calling user  
> and then compares this user's name with the name of the one and only  
> user who is allowed to continue program execution. Do you think that  
> this can be circumvented?

I'll just repeat - don't write your own setuid programs if you care
about security.  Here's an old paper that lists some (and certainly not
all!) of the things people who do write them have to understand:

  http://man7.org/conf/lca2010/writing_secure_privileged_programs.pdf

It only takes one mistake or one thing you didn't know about or
understand properly to make your system insecure.

Alasdair

  reply	other threads:[~2018-11-19 13:01 UTC|newest]

Thread overview: 20+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-11-15 16:39 [linux-lvm] lvcreate from a setuid-root binary Christoph Pleger
2018-11-15 17:57 ` Alasdair G Kergon
2018-11-16 13:43   ` Christoph Pleger
2018-11-16 15:32     ` Zdenek Kabelac
2018-11-16 16:12       ` Christoph Pleger
2018-11-16 17:21         ` Roger Heflin
2018-11-16 15:41     ` Stuart D. Gathman
2018-11-21  9:56       ` Christoph Pleger
2018-11-21  9:58         ` Vladislav Bogdanov
2018-11-21 10:23           ` Christoph Pleger
2018-11-17  0:24     ` Alasdair G Kergon
2018-11-19  8:55       ` Christoph Pleger
2018-11-19 13:01         ` Alasdair G Kergon [this message]
2018-11-19 13:19     ` Bryn M. Reeves
2018-11-19 15:17       ` Christoph Pleger
2018-11-19 15:35 ` Christoph Pleger
     [not found] <1044845531.2858991.1542636286779.ref@mail.yahoo.com>
2018-11-19 14:04 ` matthew patton
2018-11-19 15:03   ` Christoph Pleger
     [not found] <1479542688.2901829.1542643514135.ref@mail.yahoo.com>
2018-11-19 16:05 ` matthew patton
     [not found] <1657965510.4711397.1542904883060.ref@mail.yahoo.com>
2018-11-22 16:41 ` matthew patton

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