On 25 January 2016 at 17:55, Laura Abbott <labbott@xxxxxxxxxxxxxxxxx> wrote: > Hi, > > This is an implementation of page poisoning/sanitization for all arches. It > takes advantage of the existing implementation for > !ARCH_SUPPORTS_DEBUG_PAGEALLOC arches. This is a different approach than what > the Grsecurity patches were taking but should provide equivalent functionality. > > For those who aren't familiar with this, the goal of sanitization is to reduce > the severity of use after free and uninitialized data bugs. Memory is cleared > on free so any sensitive data is no longer available. Discussion of > sanitization was brough up in a thread about CVEs > (lkml.kernel.org/g/<20160119112812.GA10818@mwanda>) > > I eventually expect Kconfig names will want to be changed and or moved if this > is going to be used for security but that can happen later. > > Credit to Mathias Krause for the version in grsecurity Thanks for the credits but I don't deserve them. I've contributed the slab based sanitization only. The page based one shipped in PaX and grsecurity is from the PaX Team. > > Laura Abbott (3): > mm/debug-pagealloc.c: Split out page poisoning from debug page_alloc > mm/page_poison.c: Enable PAGE_POISONING as a separate option > mm/page_poisoning.c: Allow for zero poisoning > > Documentation/kernel-parameters.txt | 5 ++ > include/linux/mm.h | 13 +++ > include/linux/poison.h | 4 + > mm/Kconfig.debug | 35 +++++++- > mm/Makefile | 5 +- > mm/debug-pagealloc.c | 127 +---------------------------- > mm/page_alloc.c | 10 ++- > mm/page_poison.c | 158 ++++++++++++++++++++++++++++++++++++ > 8 files changed, 228 insertions(+), 129 deletions(-) > create mode 100644 mm/page_poison.c > > -- > 2.5.0 > Regards, Mathias -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>