SU command question

Steve Cronje · 07-31-2003, 12:49 PM

Quote:

Originally posted by itsjustme
Are you sure that won't just launch an additional login for barry?

I was talking about using the su command in an xterm:

Starting in an xterm as user knoppix:

knoppix@laptop:~$ su
Password:
root@laptop:/home/knoppix#

then

root@laptop:/home/knoppix# su knoppix
knoppix@laptop:~$

to get back to the prompt as user knoppix

HTH
Steve

lfur · 07-31-2003, 12:57 PM

Steve Cronje,

well X terminal and terminal in the console mode are two same things. So, when you:
su

you log in as root. There are now 2 users, you and root.
And then you said to:
su username

if you check the list of users, you will see, that there are now 3 users online:
you, root and (in your case) you again

You loged IN again and never closed the root account.

itsjustme · 07-31-2003, 01:04 PM

lfur is right.

Code:

bsl1@localhost bsl1]$ su -
Password:
[root@localhost root]# su bsl1
[bsl1@localhost root]$ exit
exit
[root@localhost root]# exit
exit
[bsl1@localhost bsl1]$
[bsl1@localhost bsl1]$ su
Password:
[root@localhost bsl1]# su bsl1
[bsl1@localhost bsl1]$ users
bsl1 bsl1
[bsl1@localhost bsl1]$

Notice, when I try to 'get back' after the first 'su bsl1' up there, I'm still in the root directory as bsl1.

regards...

Edit: well, I could be partially wrong also. Even if I type 'users' with the one and only initial gnome-terminal occurence, without any su or su -, it still says 'bsl1 bsl1'.

hmmmm.....

Steve Cronje · 07-31-2003, 03:30 PM

Quote:

Originally posted by lfur
Steve Cronje,

well X terminal and terminal in the console mode are two same things. So, when you:
su

you log in as root. There are now 2 users, you and root.
And then you said to:
su username

if you check the list of users, you will see, that there are now 3 users online:
you, root and (in your case) you again

You loged IN again and never closed the root account.

OK, look at this:

knoppix@laptop:~$ users
knoppix knoppix knoppix knoppix
knoppix@laptop:~$ su
Password:
root@laptop:/home/knoppix# users
knoppix knoppix knoppix knoppix
root@laptop:/home/knoppix# su knoppix
knoppix@laptop:~$ users
knoppix knoppix knoppix knoppix
knoppix@laptop:~$

This was taken directly from xterm, no editing.

HTH
Steve

lfur · 07-31-2003, 05:23 PM

Steve Cronje,

my bad! Yes, as you said, there are no new users when you su to root and then su to user. But when you do that, the root acount is still there. If you check with:
ps a

you will see, that there are 3 processes running shell, but it should be only one, since it should return you where you started from. And I have noticed a similar discussion, where unSpawn said, that this must be taken as a serious security risk.
So ... yes, there are no more users, but to exit from root account you MUST use exit and not just su to normal user.

Enjoy

m9dhatter · 07-31-2003, 07:41 PM

logging in again does NOT make you go back to the previous shell. it creates a new one.
for example:

myshell# su
-----rootshell# su my
----------myshell# exit
-----rootshell# exit
myshell# ( this is where you go "back" to you previous shell )

Steve Cronje · 07-31-2003, 07:53 PM

Wow, I learnt a lot from this thread! I'll be sure to use 'exit' from now on.

Thanks to all

Steve

synecdoche · 07-31-2003, 08:01 PM

To cease acting as root in a console, type exit and you'll be back to the original user.

Remember that us does not mean superuser but substitute user.

-dave

itsjustme · 07-31-2003, 08:12 PM

Well, I guess that about confirms it.

I said to use 'exit',
then lfur,
then m9dhatter,
then Steve Cronje,
then synecdoche

Anybody else?

Steve Cronje · 07-31-2003, 08:16 PM

Quote:

Originally posted by itsjustme
Well, I guess that about confirms it.

I said to use 'exit',
then lfur,
then m9dhatter,
then Steve Cronje,
then synecdoche

Anybody else?

Yes, but you used a funny accent, didn't you ;-)

Steve

itsjustme · 07-31-2003, 08:21 PM

wayul, ah am frum texsiz...