ability of unprivileged processes to modify the scheduling properties
of daemons temporarily taking on unprivileged effective credentials.
These cases (p1->p_cred->p_ruid == p2->p_ucred->cr_uid) and
(p1->p_ucred->cr_uid == p2->p_ucred->cr_uid), respectively permitting
a subject process to influence the scheduling of a daemon if the subject
process has the same real uid or effective uid as the daemon's effective
uid. This removes a number of the warning cases identified by the
proc_to_proc iner-process authorization regression test.
o As these are new restrictions, we'll have to watch out carefully for
possible side effects on running code: they seem reasonable to me,
but it's possible this change might have to be backed out if problems
are experienced.
Reported by: src/tools/regression/security/proc_to_proc/testuid
Obtained from: TrustedBSD Project
0489082737