Question about Unix

[Glitchny]

hey guys this isnt a very important question just a thing my prof asked the class to find out (Not hmwk).
The question is, Who owns a running process? In Unix

Thats all

thanx guys

 

[GhettoFob]

whoever started the process, I think...don't take my word for it though

 

[Glitchny]

Originally posted by: GhettoFob
whoever started the process, I think...don't take my word for it though

thanx, thats what i was thinking as well, but it seems that nobodsy is answering me

 

[pitupepito2000]

yeah however started the process. For example a process could be something like mozilla or konqueror which were probably initiated by you as a regular user after you logged in. Other processes are owned by other users such as root which is the admin in unix. If you type "ps aux" in a shell it will show you the processes and which user started them.

I hope this helps,
pitupepito

 

[Glitchny]

Originally posted by: pitupepito2000
yeah however started the process. For example a process could be something like mozilla or konqueror which were probably initiated by you as a regular user after you logged in. Other processes are owned by other users such as root which is the admin in unix. If you type "ps aux" in a shell it will show you the processes and which user started them.

I hope this helps,
pitupepito

thanks man, and yeah it helps

 

[cleverhandle]

Yes, generally the owner of the process is the user who created it, or who created the parent process that spawned it. Processes can run as an alternate user, however, as is often the case with daemons (e.g. www and postgresql users).

 

[drag]

Yes who started it owned it.. generally. You can set up different things like the command "sudo" or set the suid bits on programs to modify that sort of thing if you need to.

For instance if a program that runs in the counsole, but uses graphics may use the svga library. In order for that to work you need access to the hardware. By default only root can do that, so you set that program's suid bit to run as if root was the user who started it.

Needless to say that this should be avoided as much as possible. If for instance you made a bash shell script file run as suid root and it requires interaction from a user a malicious user could use that to break out of the script and get a command line. That way they get a command line that is run with the same permissions as root.

So that is definately to be avoided. Same thing with perl scripts and other types of scripts that are run on (for instance) a web server. If there is a bug in your programming a attacker could use the online script to send commands to you computer as if they were the user that runs that webserver or get to restricted parts of the website.

The main thing to keep in mind is that a proccess doesn't have any more rights then the person who started them, exept under special circumstances like I outlined above. So if I am a regular user and have no rights to anything outside my own home folder, then any program that I run cannot modify anything outside my home folder too. However if I ran the same program as root it would be able to access and modify any part of the system which could be very bad if it had a trojan or was simply broken and tried to modify some system files.