[RFC PATCH v16 0/6] mm: security: ro protection for dynamic data

From: Igor Stoppa
Date: Mon Feb 12 2018 - 11:53:39 EST


This patch-set introduces the possibility of protecting memory that has
been allocated dynamically.

The memory is managed in pools: when a memory pool is turned into R/O,
all the memory that is part of it, will become R/O.

A R/O pool can be destroyed, to recover its memory, but it cannot be
turned back into R/W mode.

This is intentional. This feature is meant for data that doesn't need
further modifications after initialization.

However the data might need to be released, for example as part of module
unloading.
To do this, the memory must first be freed, then the pool can be destroyed.

An example is provided, in the form of self-testing.

Changes since v15:
[http://www.openwall.com/lists/kernel-hardening/2018/02/11/4]

- Fixed remaining broken comments
- Fixed remaining broken "Returns" instead of "Return:" in kernel-doc
- Converted "Return:" values to lists
- Fixed SPDX license statements

Igor Stoppa (6):
genalloc: track beginning of allocations
genalloc: selftest
struct page: add field for vm_struct
Protectable Memory
Pmalloc: self-test
Documentation for Pmalloc

Documentation/core-api/index.rst | 1 +
Documentation/core-api/pmalloc.rst | 114 +++++++
include/linux/genalloc-selftest.h | 26 ++
include/linux/genalloc.h | 7 +-
include/linux/mm_types.h | 1 +
include/linux/pmalloc.h | 242 ++++++++++++++
include/linux/vmalloc.h | 1 +
init/main.c | 2 +
lib/Kconfig | 15 +
lib/Makefile | 1 +
lib/genalloc-selftest.c | 400 ++++++++++++++++++++++
lib/genalloc.c | 658 +++++++++++++++++++++++++++----------
mm/Kconfig | 15 +
mm/Makefile | 2 +
mm/pmalloc-selftest.c | 64 ++++
mm/pmalloc-selftest.h | 24 ++
mm/pmalloc.c | 501 ++++++++++++++++++++++++++++
mm/usercopy.c | 33 ++
mm/vmalloc.c | 18 +-
19 files changed, 1950 insertions(+), 175 deletions(-)
create mode 100644 Documentation/core-api/pmalloc.rst
create mode 100644 include/linux/genalloc-selftest.h
create mode 100644 include/linux/pmalloc.h
create mode 100644 lib/genalloc-selftest.c
create mode 100644 mm/pmalloc-selftest.c
create mode 100644 mm/pmalloc-selftest.h
create mode 100644 mm/pmalloc.c

--
2.14.1