On Thu, Nov 24, 2016 at 10:28:56PM +0900, Masanobu SAITOH wrote: > > Put a one-page redzone between userland and the PTE space on amd64 and > > i386. > > > > The PTE space is a critical region that maps the page tree, and bugs have > > been found in both amd64 and i386 where the kernel would wrongly overflow > > userland data on this area. This kind of bug is terrible, since it allows > > userland to overwrite some entries of the page tree, which makes it easy > > to patch the kernel text and get ring0 privileges. > > My emacs dumps core with change. > > What should we do?
Make maxv clean up his mess, or rebuild emacs. It seems that the stack location gets baked in somehow when emacs dumps, although I don't really see exactly how (see PR 51654) and this causes existing emacs binaries to stop working. -- David A. Holland dholl...@netbsd.org