Which commands (in /bin & /usr/bin) must have set user ID (for root)

#Bill.Stewart wcs at ho95e.UUCP
Sat Oct 18 12:37:39 AEST 1986


In article <735 at hropus.UUCP> jrw at hropus.UUCP (Jim Webb) writes:
>>[Somebody else wrote..]
>> I currently have VAX 11/785s running AT&T UNIX V Release 2 Version 2.0.
>> I am wondering which commands in /bin /and /usr/bin (owned by root, group is
>> sys)  must have the set user ID, or set group ID on execution in order
>> to work correctly.

What surprised me about the list Jim replied with was that most of the commands
were -rws......!  Why should a setuid command *ever* be writeable? - it's just
*inviting* attempts to find a bug and convince the command to write over itself.
Are there any commands that actually depend on this?



>-rwsr-xr-x   1 root     sys        47197 Oct 20  1985 at
>-rwsr-xr-x   1 root     sys        25093 Nov  5  1983 crontab
>at needs to talk to cron in a very specific manner.
I would expect you could write a good cron without setuid, since /etc/cron runs
as root?  Likewise "at", since it's the other side of cron?

What irks me more, though, is that the "lp" commands all run setuid-lp
setgid-bin; this means that in a directory which lp can't access ( e.g. 700),
	lp foo
fails, though
	lp <foo
is ok.
-- 
# Bill Stewart, AT&T Bell Labs 2G-202, Holmdel NJ 1-201-949-0705 ihnp4!ho95c!wcs



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