topic Re: sgid question (really scratching my head!!!!) in Operating System - Linux

sgid question (really scratching my head!!!!)

joseph wholey — Mon, 25 Sep 2006 15:11:45 GMT

Why, can't user "manager" change the permissions on file /depts/hr/mgr.sh? Group has rwx.

[manager@jgwlinux /]$ id manager
uid=521(manager) gid=521(manager) groups=521(manager),10000(sales),10001(hr),10002(web)

[manager@jgwlinux /]$ ls -ld /depts
drwxr-xr-x 5 root root 4096 Sep 25 13:54 /depts

[manager@jgwlinux /]$ ls -la /depts
total 36
drwxr-xr-x 5 root root 4096 Sep 25 13:54 .
drwxr-xr-x 25 root root 4096 Sep 24 20:17 ..
drwxrws--- 2 root hr 4096 Sep 25 15:43 hr

[manager@jgwlinux hr]$ ls -la /depts/hr
total 20
drwxrws--- 2 root hr 4096 Sep 25 15:43 .
drwxr-xr-x 5 root root 4096 Sep 25 13:54 ..
-rw-rw-r-- 1 manager hr 35 Sep 25 15:10 mgr.sh

Re: sgid question (really scratching my head!!!!)

Ivan Ferreira — Mon, 25 Sep 2006 15:29:56 GMT

Only the user owner can change the permissions of a file. Group permissions indicates if the file can be read, writed or executed, but does not indicates that the permissions can be modified.

Re: sgid question (really scratching my head!!!!)

joseph wholey — Mon, 25 Sep 2006 17:06:10 GMT

Ivan, ok... that makes sense. Which leads me to my next question: how then (without intervention from root), can the user manager create a file in the /depts/hr directory that is executable? e.g. mgr.sh.

Re: sgid question (really scratching my head!!!!)

Ivan Ferreira — Mon, 25 Sep 2006 17:17:49 GMT

Wait a minute, I was seeing wrong your previous post, I was thinking that the owner of mgr.sh was root.hr. In this case, the owner of mgr.sh is manager, so it should be able to change the permissions of the file.

What happens if you try to change the permissions of the file? what is the command that you use? what is the error that you get?

Re: sgid question (really scratching my head!!!!)

joseph wholey — Mon, 25 Sep 2006 17:37:29 GMT

Ivan... thanks for your help. It was an oversight. sorry!!!