setuid and root

[Lauren@ucla-security]

Has anybody ever decided whether the following is a bug? ...

In at least some versions of V7 Unix, the setuid bit on a program is
ignored if the running user is already uid 0. So, for example, a person
who writes a game program that is setuid to himself will have things
considerably fouled up if root ever tries to run it, since root will
not be changed to that user's id. Apparently setgid DOES take effect
for root, however. Is this a bug or a feature?

--Lauren--
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