Chmod a link file

[John Ferrara]

How do I chmod a link file w/o changing the file it's linked to?

lrwxr-xr-x 1 root sys 27 Oct 24 2001 snmpd.conf -> /etc/SnmpAgent.d/snmpd.conf

I want to change the link to 0440.

John

[Pete Randall]

John,

Remove the link, set your umask and recreate the link.


Pete

[James R. Ferguson · Accepted solution]

Hi John:

First, the permissions and ownership of a link do not matter.

To change the permissions of the link, remove the link (the entity to which it points is untouched); set the 'umask' you want; and recreate the link.

In the case of a link's ownership, using the '-h' option of 'chown' causes the ownership or group change to apply to the link and not the target.

Regards!

...JRF...

[Donny Jekels]

john,

perms on a link is inherrited from the umask of the directory.

those does'nt matter anyway since the linked binary controls the execution rights.

everyone else has giving you the correct method to fix the link perms.

live free or die
donny

[Jeff Schussele]

Hi John,

The perms on the link are irrelevant. The destination perms are what count.

Rgds,
Jeff

[John Ferrara]

What should the umask setting be to acheive 0440 file?

John

[Donny Jekels]

umask 337

[Umapathy S]

337

-Umapathy

[John Ferrara]

Thanks for all the quick responses. I understand that the perms on the link are irrelevant. However, I run security scans that check for that sort of thing and if I don't correct it I have to explain why to Big Brother.

Thanks,
John

[Jeff Schussele]

Hi John,

I certainly feel your pain.
This is one of my pet peeves.
What good are scans if the personnel conducting them have NO clue to the relevance of the output?
You should hold firm on this one & make it VERY clear to mgmnt that in this case they are simply wasting resources. Remind them that EVERY time a link is created or recreated there will be an absolutely unnecessary waste of resources to set link perms. At the least mgmnt should simply ask the scanners WHY they think the link perms are important.

MORAL - Even the best SA can't fix stupid.

Rgds,
Jeff (OK, my rant's over)

[John Ferrara]

Jeff,

Thanks for sharing. I would like to share that info w/ mngt. However, I like my job and the low man on the toteum pole doesn't have much of a voice. Besides, if I didn't have all of these security issues to correct, I probably wouldn't have a job here for long ;-)

John