On Tue, Nov 02, 2010 at 04:04:13PM +0100, maximilian attems wrote: > hello Kees, > > On Fri, 29 Oct 2010, Kees Cook wrote: > > > Thanks for adding this to the agenda! I've added details about both > > AppArmor and the nx-emulation bits to the wiki page. Let me know if > > you've got any questions. > > Do you know if newly split out 32bit-mmap-exec-randomization > has a chance in going upstream or has already been submitted?
I would fight it going upstream as it has terrible entropy. I feel it only has value when combined with the nx-emu patch, which would have 0 entropy for the relocated executable regions if left as-is. The goal discussed on the Fedora kernel list was to somehow get rewrites of the existing upstream ASLR so that it could be used with the nx-emu patch and then the 32bit-mmap-exec-randomization could be eliminated. The feature 32bit-mmap-exec-randomization is trying to implement is "ASCII armor" (leading 0 byte on addresses), but it's greedy-fit method creates a nearly deterministic layout for each given ELF. So if a way to do ASCII armor with the upstream ASLR can be created, it can be dropped. There has been no progress on this, though. -Kees -- Kees Cook @debian.org -- To UNSUBSCRIBE, email to [email protected] with a subject of "unsubscribe". Trouble? Contact [email protected] Archive: http://lists.debian.org/[email protected]
