On Wed, Nov 04, 2009 at 03:45:33PM +0100, Justin Smith wrote: > Theo wrote: > > > For the record, this particular problem was resolved in OpenBSD a > while back, in 2008. > > Nice, but: > > "Since 2.6.23, it has been possible to prevent applications from > mapping low pages (to prevent null pointer dereferencing in the > kernel) via the /proc/sys/vm/mmap_min_addr sysctl, which sets the > minimum address allowed for such mappings." > > 2.6.23 released: Tue, 9 Oct 2007 > > Ref: > http://lkml.org/lkml/2007/10/9/241 > http://james-morris.livejournal.com/26303.html > > -- > JS
Optional prevention is not worth a lot. -Otto