Monday, October 24th 2016, 3:59pm UTC+2

You are not logged in.

  • Login
  • Register

Dear visitor, welcome to NAS Forum. If this is your first visit here, please read the Help. It explains how this page works. You must be registered before you can use all the page's features. Please use the registration form, to register here or read more information about the registration process. If you are already registered, please login here.


Thursday, July 14th 2011, 5:31am

su: must be suid to work properly

Hello everybody

I 've a SohoNas for about 3 years, flashed with Tinky firmware (from Treepleks), working well in nfs until the supply burnt about 1 year ago. At that time I replaced it by a cheap NAS1000, which i also flashed with the Tinky, then just reformatting the first partition of the SohoNas disk, thus keeping all my data. :thumbsup:

Recently however, I found a used supply for 6 €, so, just for fun,( well not only, I'd like to mirror my data), I plugged an old 80 GO DD in the SohoNas and restart it. Of course, like the first time, I had to exchange the dropbearmulti that is corrupted in the Treepleks flash, then install the missing, all done by direct connexion to the PC through USB. See link to for reference.
Everything works fine again (nfs, ssh, web) but I cannot become root using su -. X( I always receive the message :

Source code

su: must be suid to work properly

whichever the normal account I start from. I first checked that they are both correctly registered in the wheel group. I finally discovered that /bin/busybox which provides su (and in fact almost all commands) has not its set UID :hmm: , i.e. the unix rights are

Source code

rwxr-xr-x instead of rwsr-xr-x

which I also verified from the NAS1000. After connecting directly as root through ssh (with the by default password from the treepleks firmware, don't forget to change it later), i could finally change the rights with

Source code

chmod 4755 /bin/busybox

and su works fine again. I just publish that story, as awareness of rights administration under Linux is not so widely spread.

So in the hope it will help someone else. :weizen:



Posts: 1,001

Location: Wien


Thursday, July 14th 2011, 7:47am

Hi jackrio,
thank you very much for the story. :happy:


P.S. I removed a double url command in your post which prevented the link from being displayed
Leute ohne Laster haben oft wenige Tugenden...
NAS2000 2.3.2.IB.2.RS.1+Lüfterabschaltung+SSH+do_it+zusätzliche commandline tools+changed root password
1. suchen - lesen - Google - lesen - 1. Fragen gehören ins Forum, dann profitieren alle davon!