[cip-dev] [PATCH 4.4-cip 0/6] Extend user-space ASLR range

[agustin.benito@codethink.co.uk (Agustin Benito Bethencourt)]

Hi,

On 08/12/16 23:56, Ben Hutchings wrote:
> This is a backport of changes in 4.5 to extend the range of Address
> Space Layout Randomisation for user-space processes.  When enabled, this
> should make some user-space vulnerabilities harder to exploit, but it
> can also cause some applications to fail if they currently use a large
> proportion of the virtual address space.
>
> The default ASLR range remains the same, but it can be changed through
> kernel config (CONFIG_ARCH_MMAP_RND_BITS) or at run-time through sysctl
> (vm.mmap_rnd_bits).  (For 32-bit compat tasks, the range is controlled
> through CONFIG_ARCH_MMAP_RND_COMPAT_BITS and vm.mmap_rnd_compat_bits.)
>
> This includes support for arm, arm64 and x86 (32- and 64-bit).  (arm64
> is not currently supported by CIP, but it was easier to include it in
> the backport than to leave it out.)
>
> For this and other backports, I'm looking for feedback like:
> - Did I miss a follow-up fix or an earlier dependency?
> - Does this cause a regression (other than as explained above)?
> - Are you likely to use it?
> - Are there related features you want in 4.4?

since there is no further feedback, I assume you me merge the patches, 
isn't is?

Hopefully in a couple or three more weeks we can start testing it with 
kernelci tooling.

>
> Ben.
>
> Daniel Cashman (6):
>    mm: mmap: add new /proc tunable for mmap_base ASLR
>    arm: mm: support ARCH_MMAP_RND_BITS
>    arm64: mm: support ARCH_MMAP_RND_BITS
>    x86: mm: support ARCH_MMAP_RND_BITS
>    drivers: char: random: add get_random_long()
>    mm: ASLR: use get_random_long()
>
>   Documentation/sysctl/vm.txt      | 29 +++++++++++++++++
>   arch/Kconfig                     | 68 ++++++++++++++++++++++++++++++++++++++++
>   arch/arm/Kconfig                 |  9 ++++++
>   arch/arm/mm/mmap.c               |  3 +-
>   arch/arm64/Kconfig               | 29 +++++++++++++++++
>   arch/arm64/mm/mmap.c             |  8 +++--
>   arch/mips/mm/mmap.c              |  4 +--
>   arch/powerpc/kernel/process.c    |  4 +--
>   arch/powerpc/mm/mmap.c           |  4 +--
>   arch/sparc/kernel/sys_sparc_64.c |  2 +-
>   arch/x86/Kconfig                 | 16 ++++++++++
>   arch/x86/mm/mmap.c               | 12 +++----
>   drivers/char/random.c            | 22 +++++++++++++
>   fs/binfmt_elf.c                  |  2 +-
>   include/linux/mm.h               | 11 +++++++
>   include/linux/random.h           |  1 +
>   kernel/sysctl.c                  | 22 +++++++++++++
>   mm/mmap.c                        | 12 +++++++
>   18 files changed, 240 insertions(+), 18 deletions(-)
>

-- 
Agustin Benito Bethencourt
Principal Consultant - FOSS at Codethink
agustin.benito at codethink.co.uk