hazards of linking directories

[tom at uwai.UUCP]

>      This is a strong argument against running utilities such as the
> line printer spooler as ``setuid to root''.  Such programs should
> open the file of interest while running as the requestor and then
> exec a second program which is set-uid to a service user id which owns
> the spooling directory, after which a copy can be performed.  This
> is a little more complex but much safer.

Why the added work of an extra exec?  Just make sure that the real uid
(not the effective one) can access the file.

Also: please make sure the subject line has *some* bearing on the content.
	  I don't see what setuid programs have to do with the hazards of
	  linking directories.

tom
-- 

Tom Christiansen
University of Wisconsin
Computer Science Systems Lab 
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tom at wisc-crys.arpa