Re: documentation bug (uid resetting in posix mode)

[Chet Ramey]

On 10/30/12 1:53 PM, Stefano Lattarini wrote:
> On 10/30/2012 06:28 PM, Andreas Schwab wrote:
>> Stefano Lattarini <stefano.lattarini@gmail.com> writes:
>>
>>>   $ ./system-suid
>>>   [8204] ruid = 1000, euid = 0, suid = 0
>>
>> Looks like your /bin/sh is broken.
>>
> How "broken" exactly?  Honest question.

It's not unheard of for vendors to make their own changes and ship the
result.  This has happened a number of times in the past.

> 
> Anyway, my /bin/sh is bash ...
> 
>   $ ls -l /bin/sh
>   lrwxrwxrwx 1 root root 4 Jul  8  2010 /bin/sh -> bash
> 
>   $ /bin/sh --version
>   GNU bash, version 4.2.20(1)-release (i486-pc-linux-gnu)
>   Copyright (C) 2011 Free Software Foundation, Inc.
>   License GPLv3+: GNU GPL version 3 or later 
> <http://gnu.org/licenses/gpl.html>
> 
>   This is free software; you are free to change and redistribute it.
>   There is NO WARRANTY, to the extent permitted by law.
> 
> I'm on Debian Unstable BTW (sorry for not specifying that earlier).

You should open a bug report with Debian.  This behavior has been noted
previously; look at one of the footnotes to answer 2 in

http://stackoverflow.com/questions/556194/calling-a-script-from-a-setuid-root-c-program-script-does-not-run-as-root

for example.

Chet
-- 
``The lyf so short, the craft so long to lerne.'' - Chaucer
                 ``Ars longa, vita brevis'' - Hippocrates
Chet Ramey, ITS, CWRU    chet@case.edu    http://cnswww.cns.cwru.edu/~chet/