Subject: Re: chroot(2)
To: None <>
From: Greg A. Woods <>
List: tech-kern
Date: 10/02/1998 21:03:29
[ On Fri, October 2, 1998 at 09:11:32 (-0700), Eduardo E. Horvath wrote: ]
> Subject: Re: chroot(2) 
> OTOH, these changes will prevent the OS from virtualizing itself since
> the root -> user -> root transition would be disallowed.  Is reaquiring
> root privilege safe under the present scheme?

Allowing a setuid-root process to reacquire its effective ID after
becoming somone else is *never* "safe".  Period.  End of discussion.  It
breaks the basic tennant of Unix super-user and setuid design:  the only
way a process can (re)gain privilege is to exec a setuid binary.

							Greg A. Woods

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