current version of FreeBSD, this isn't guarenteed by the API. Custom
security modules, or future implementations of the setuid and setgid
may fail.
PR: bin/172289
PR: bin/172290
PR: bin/172291
Submittud by: Erik Cederstrand <erik@cederstrand.dk>
Discussed by: freebsd-security
Approved by: cperciva
MFC after: 1 week
In addition to adding `static' where possible:
- bin/date: Move `retval' into extern.h to make it visible to date.c.
- bin/ed: Move globally used variables into ed.h.
- sbin/camcontrol: Move `verbose' into camcontrol.h and fix shadow warnings.
- usr.bin/calendar: Remove unneeded variables.
- usr.bin/chat: Make `line' local instead of global.
- usr.bin/elfdump: Comment out unneeded function.
- usr.bin/rlogin: Use _Noreturn instead of __dead2.
- usr.bin/tset: Pull `Ospeed' into extern.h.
- usr.sbin/mfiutil: Put global variables in mfiutil.h.
- usr.sbin/pkg: Remove unused `os_corres'.
- usr.sbin/quotaon, usr.sbin/repquota: Remove unused `qfname'.
The privs.h header is not only used by at(1), it's also used by
atrun(8). Just let the code the way it used to be (for now).
Reported by: kwm, tinderbox
Hat to: me
Fixed macros for temporarily relinquishing and restoring setuid/setgid
privileges so that they never change the real user and group IDs of
the calling process.
The setre[ug]id() calls are still used in the REDUCE_PERM macro (with
the r[ug]id arguments of -1) so that the call changes the saved user
and group IDs of the process to that specified.
Also, the panic() and perr() functions had insufficient privileges to
delete the problematic file under /var/at.
