[pve-devel] [RFC pve-common] Add user to run_command

[Wolfgang Link]

My be we can fork and set the id.

> Dietmar Maurer <dietmar at proxmox.com> hat am 18. Mai 2016 um 18:11 geschrieben:
> 
> 
> > I discuss with Wolfgang and we will change some things.
> > Set Home Dir.
> > Check if setuid and setguid worked.
> > Check User.
> > 
> > So I will send a patch V2.
> > 
> > We can set the ID back on the end of the function.
> > I think this make sense.
> 
> But it is not trivial. Please read:
> 
> # man setuid
> 
> If the user is root or the program is set-user-ID-root, special care must  be
>  taken.   The  setuid()  function
>        checks the effective user ID of the caller and if it is the superuser,
> all process-related user ID's are set to
>        uid.  After this has occurred, it is impossible for the program to regain
> root privileges.
> 
>        Thus, a set-user-ID-root program wishing to temporarily drop root
> privileges, assume the identity of an unpriv‐
>        ileged  user,  and  then  regain  root  privileges afterward cannot use
> setuid().  You can accomplish this with
>        seteuid(2).