If this was to be extended with cached global syscall information like gettimeofday, would we want that to be in a separate page that is marked non-executable? Is there any way to trick the kernel into leaking arbitrary (and thus executable) code? Also, would it matter for jails? Per-process info like getpid would obviously have to be a separate per-process page. Scott On Jun 14, 2011, at 10:08 AM, K. Macy wrote: > http://svnweb.freebsd.org/base/head/sys/sys/imgact.h > > kib added rudimentary support for this in January > > On Tue, Jun 14, 2011 at 6:11 PM, Luigi Rizzo <rizzo_at_iet.unipi.it> wrote: >> there were discussions at some point on an imprecise but >> fast implementations of gettimeofday() that would not require >> a system call (perhaps mmapping some memory region which >> is opportunistically updated). >> >> Does anyone remember what happened about that ? >> >> Otherwise, is there any place in the kernel where i can fetch >> a struct timeval which is not off by more than, say 1 tick ? >> >> cheers >> luigi >> _______________________________________________ >> freebsd-current_at_freebsd.org mailing list >> http://lists.freebsd.org/mailman/listinfo/freebsd-current >> To unsubscribe, send any mail to "freebsd-current-unsubscribe_at_freebsd.org" >> > _______________________________________________ > freebsd-current_at_freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-current > To unsubscribe, send any mail to "freebsd-current-unsubscribe_at_freebsd.org"Received on Wed Jun 15 2011 - 18:49:47 UTC
This archive was generated by hypermail 2.4.0 : Wed May 19 2021 - 11:40:14 UTC